Enhancement of NH+ Uptake by NO3 - in Relation to Expression of Nitrate-Induced Genes in Rice
如何提升声音强度英语作文
如何提升声音强度英语作文Title: Enhancing Vocal Strength: Techniques to Amplify Your Voice。
In our journey to become effective communicators, one crucial aspect is often overlooked the strength and powerof our voice. Whether it's delivering a speech, presenting ideas, or engaging in conversations, a strong and commanding voice can significantly enhance our impact. Here, we delve into various techniques to amplify your voice:1. Breathing Techniques:Effective breathing forms the foundation of a powerful voice. Practice deep breathing exercises to expand your lung capacity and support your voice with an ample air supply. Diaphragmatic breathing, where you breathe deeply from the diaphragm rather than shallowly from the chest,can greatly enhance vocal strength.2. Posture and Alignment:Proper posture is essential for optimal vocal projection. Stand tall with your shoulders relaxed and your spine straight. Aligning your body correctly allows for better airflow and resonance, enabling your voice to carry farther and sound stronger.3. Resonance and Placement:Experiment with different resonance points to find where your voice sounds the fullest and richest. Resonance can be felt in various parts of the body, such as the chest, throat, and mask (the area around the nose and cheekbones). By consciously placing your voice in these resonating areas, you can amplify its strength and richness.4. Articulation and Pronunciation:Clear articulation and precise pronunciation are fundamental for a powerful voice. Practice enunciating each word distinctly and avoid mumbling or slurring. Payattention to consonant sounds, as they provide clarity and definition to your speech.5. Volume Control:While projecting your voice is essential, it's equally important to have control over your volume. Practice modulating your voice to suit different situations and environments. Knowing when to speak softly for emphasis and when to raise your voice for impact is key to maintaining listener engagement.6. Pitch Variation:Monotonous speech can quickly lose the audience's interest. Experiment with varying your pitch to add dynamism and energy to your voice. Incorporate highs and lows, and utilize inflection to convey emotion and emphasis effectively.7. Vocal Warm-Up Exercises:Just as athletes warm up before a game, vocal warm-up exercises prepare your voice for optimum performance. Humming, sirening, lip trills, and tongue twisters can help relax and loosen vocal muscles, ensuring a powerful and flexible voice.8. Practice and Feedback:Like any skill, vocal strength improves withpractice and feedback. Record yourself speaking and listen for areas of improvement. Seek constructive criticism from peers, mentors, or vocal coaches to refine your technique and enhance your vocal prowess.9. Confidence and Mindset:Confidence plays a significant role in vocal strength. Believe in the power of your voice and the message you convey. Adopting a positive mindset and embracing nerves as natural can help you channel your energy into a commanding vocal presence.In conclusion, mastering the art of vocal strength requires dedication, practice, and a willingness to explore and refine your technique continuously. By incorporating these techniques into your routine and embracing your unique vocal qualities, you can amplify your voice and captivate your audience with compelling communication.。
提高创新的措施英文作文
提高创新的措施英文作文Title: Sparking Innovation: Unleashing Creativity in the Modern Age。
1. Embrace Diverse Perspectives:In the realm of innovation, it's not about adhering to a single formula; it's about embracing diversity. Encourage cross-functional teams, where individuals with contrasting backgrounds bring unique insights. Let's foster an environment where "thinking out of the box" is not just a buzzword, but a daily practice.2. Encourage Risk-taking:Innovation thrives on taking calculated risks. Don't fear failure; instead, see it as a stepping stone to learning. Reward those who dare to experiment, and let the fear of failure be the catalyst for breakthroughs.3. Empower Continuous Learning:Invest in your workforce's growth by fostering aculture of continuous learning. Provide opportunities for training, workshops, and access to the latest technologies. Remember, "knowledge is the new currency."4. Foster Collaboration:Collaboration is the oxygen for innovation. Encourage open dialogue, brainstorming sessions, and constructive criticism. Let ideas bounce off walls and germinate into innovative solutions.5. Embrace Failure as Feedback:Instead of shying away from setbacks, view them as feedback loops. Learn from your failures and adapt, because "every stumble is a chance to dance."6. Embrace Disruptive Technologies:Stay ahead of the curve by embracing disruptive technologies. Don't resist change; instead, lead the change. Be the first to adopt and iterate on new ideas.7. Foster a Culture of Adaptability:In a rapidly changing world, adaptability is key. Be agile and ready to pivot when needed. "The future belongsto those who can adapt."8. Celebrate Success and Failure:Celebrate both successes and failures as milestones on the journey to innovation. Recognize the value in each, as they both contribute to the collective growth.In conclusion, fostering innovation isn't a one-time event; it's an ongoing process. By nurturing these principles, you'll unlock the full potential of your team and create a dynamic, innovative organization. So, let's embrace the spirit of chatgpt always ready to learn, adapt, and create!。
预氧化技术
3 Introduction
• ClO2 oxidation prior to chlorination can reduce the levels of THM and total organic halogen (TOX) formation (Lykins and Griese,1986; Linder et al., 2006 ).
(1) the changes of NOM properties with ClO2 pretreatment.
(2) the formation of regulated and emerging DBPs from ClO2 preoxidation and in combination with chlorination or chloramination.
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• 与浊度不同,滤后水高锰酸盐指数自运行开始后一直保持稳定,说 明生物过滤对水中易氧化有机物的去除相关性不大;滤后水UV254 变化很小,说明难生物降解(shēnɡ wù jiànɡ jiě)有机物很难在生物 过滤中被去除; O3 —生物过滤对DOC 的去除率稍高。O3 和PPC 预氧化后SUVA 相对于空白试验分别降低和升高(见表1) ,而 O3 —生物过滤出水SUVA 升高较明显(见表2) ,说明O3 预氧化更 有助于生物过滤对可生物降解(shēnɡ wù jiànɡ jiě)有机物的去除。
transformed large aromatic and long aliphatic chain organic structures to small
and hydrophilic organics.
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Conclusion
溶解氧控制对枯草芽孢杆菌发酵生产腺苷的影响
溶解氧控制对枯草芽孢杆菌发酵生产腺苷的影响刘剑;徐达【摘要】在50L的生物反应器中，通过控制溶解氧水平为5％、10％、20％、30％四个水平考察枯草芽孢杆菌发酵生产腺苷的影响，发现该菌株生长的溶解氧浓度在10％-20％。
并通过发酵过程中菌株的生长情况、菌体摄氧率和发酵产苷进行相关分析。
结果表明，在发酵过程中DO水平控制在10％～20％时腺苷积累量高，发酵液中DO水平为5％和30％均不利于发酵液中的腺苷积累。
通过对发酵终点丙酮酸的检测，发现枯草芽孢杆菌在低溶氧状态下比高溶氧状态下积累更多的丙酮酸。
在此基础上，提出两阶段DO控制策略，最终腺苷积累量达到20．1g／L。
%The effect of oxygen supply on adenosine production of Bacillus subtilis was studied using 50L fermen- tor with the air saturation at 5% , 10% , 20% and 30%. We found that the concentration of the critical dissolved oxy- gen in the industrial strains was 10% - 20%. The relationship among strain growths, oxygen uptake rate in the process and dissolved oxygen （DO）tension on adenosine accumulation was analyzed. The results showed that during the adenosine fermentation of Bacillus subtilis, it was better to control DO at 10% -20% than at 5% and 30%. We found that the concentration of pyruvate at the final time of fermentation was higher under low oxygen condition than that under high oxygen condition. Based on the results, a strategy of two stages for DO manipulation was proposed. With this strategy, the adenosine accumulated in 50L fermentor ultimately reached 20. l g/L.【期刊名称】《食品与发酵工业》【年(卷),期】2012(038)007【总页数】4页(P86-89)【关键词】枯草芽孢杆菌;发酵;腺苷;溶解氧【作者】刘剑;徐达【作者单位】广东肇庆星湖生物科技股份有限公司,广东肇庆526060;广东肇庆星湖生物科技股份有限公司,广东肇庆526060【正文语种】中文【中图分类】TQ929腺苷(Adenosine)又称腺嘌呤核苷，具有促进冠状动脉扩张及心肌代谢的机能，扩张血管，增加冠血量的药理作用，可用于治疗冠状血管障碍、狭心症、动脉硬化症及高血压症等疾病，具有广泛的药用价值。
低强度超声波对高负荷厌氧氨氧化EGSB反应器运行性能的影响
化工进展Chemical Industry and Engineering Progress2024 年第 43 卷第 2 期低强度超声波对高负荷厌氧氨氧化EGSB 反应器运行性能的影响杨杰源1，朱易春1，赖雅芬1，张超1，田帅2，谢颖1（1 江西理工大学赣州市流域污染模拟与控制重点实验室，江西 赣州 341000；2 江西理工大学资源与环境工程学院，江西 赣州 341000）摘要：研究了低强度超声波对厌氧氨氧化EGSB 反应器处理无机高氨氮废水的影响，考察了超声波处理对反应器脱氮性能、厌氧氨氧化颗粒污泥特征、胞外聚合物以及微生物菌群的变化情况。
结果表明，低强度超声波可提高厌氧氨氧化反应器脱氮效能，在进水氮负荷为6.03kg N/(m³·d)时，总氮去除率提高了11.40%，抵抗氮负荷冲击能力也得到了增强。
周期性超声波辐照后，颗粒污泥粒径维持在1.0~1.5mm ，有利于改善传质效率，提升厌氧氨氧化颗粒污泥活性和减少颗粒漂浮。
污泥EPS 总量有显著增加，其中紧密结合型胞外聚合物（TB-EPS ）增加较为明显，有助于维持颗粒污泥的结构稳定性。
污泥表面官能团种类不变，但羟基、羧基、氨基等基团有所增多。
颗粒污泥的比厌氧氨氧化活性提高了33.2%，通过简化的Gompertz 方程模型发现超声组的厌氧氨氧化菌生长速率（0.0127d -1）高于对照组（0.0107d -1）。
高通量测序显示，超声波促进了厌氧氨氧化菌及其共生菌，其中Candidatus Brocadia 提升了22.03%。
同时严重抑制了部分反硝化细菌，使厌氧氨氧化菌的底物和生存空间更加充足。
关键词：低强度超声波；厌氧氨氧化；颗粒污泥；微生物群落；氮负荷中图分类号：X703.1 文献标志码：A 文章编号：1000-6613（2024）02-1098-11Effect of low intensity ultrasound on operation performance of high loadAnammox-EGSB reactorYANG Jieyuan 1，ZHU Yichun 1，LAI Yafen 1，ZHANG Chao 1，TIAN Shuai 2，XIE Ying 1(1 Ganzhou Key Laboratory of Basin Pollution Simulation and Control, Jiangxi University of Science and Technology,Ganzhou 341000, Jiangxi, China; 2 School of Resources and Environmental Engineering, Jiangxi University of Science andTechnology, Ganzhou 341000, Jiangxi, China)Abstract: The effect of low intensity ultrasound on the treatment of high-ammonia-nitrogen wastewater by Anammox-EGSB reactor was studied. The effects of ultrasound treatment on the nitrogen removal performance of the reactor, characteristics of Anammox granular sludge, extracellular polymer and microbial flora were investigated. The results showed that low intensity ultrasound could improve the nitrogen removal efficiency of Anammox reactor, and the nitrogen load of influent was 6.03kg N/(m³·d), the total nitrogen removal rate of ultrasonic group was increased by 11.40%, and the impact resistance of nitrogen load was also enhanced. After periodic ultrasonic irradiation, the particle size of granular sludge研究开发DOI ：10.16085/j.issn.1000-6613.2023-0315收稿日期：2023-03-02；修改稿日期：2023-04-02。
Health and Safety Executive潜水信息表说明书
Health and SafetyIntroductionThis diving information sheet (DVIS) is part of a series of information sheets providing guidance on diving at work. It identifies the correct standard to be used for assessing the quality of divers’ breathing gas taking into account the 2014 version of BS EN 12021. It details the requirements for breathing gas composition and also provides guidance on the frequency of tests. Unit symbols and measurement Throughout this DVIS extracts from EH40/2005 Workplace Exposure Limits1 and BS EN 12021:2014 Respiratory equipment – Compressed gases for breathing apparatus2 are shown as ml m-3,mg m-3 and ppm (parts per million by volume). LegislationThe Control of Substances Hazardous toHealth Regulations 2002 (as amended) (COSHH)3 and the associated Approved Codeof Practice (ACOP) and guidance4 apply. Standard for divers’ breathing gasesBS EN 12021:20142 supersedes the previous1998 version of the standard and is the appropriate standard for compressed breathing gases usedby divers. The 2014 version of the standard provides details of the composition of breathingair, as well as the following breathing gases:n oxygen compatible air;n nitrogen depleted air;n oxygen enriched air;n breathing oxygen;n oxygen and nitrogen gas mixtures;n oxygen and helium gas mixtures;n oxygen, helium and nitrogen gas mixtures. Standards for divers’ breathing airThe standards for breathing air in BS EN 12021:20142 are detailed in Table A:Table A Composition of breathing air Component Concentration atatmospheric pressure Oxygen In the range of (21 +/- 1) % Carbon dioxide Less than or equal to500 ml m-3 (500 ppmby volume)Carbon monoxide Less than or equal to5 ml m-3 (5 ppm by volume) Oil Less than or equal to0.5 mg m-3 (Droplets or mist) Odour/taste No significant odour or taste Liquid water None presentWater contentThere should not be any free liquid water content in the breathing gas. The breathing gas must havea dew point sufficiently low to prevent condensation and freezing. The dew point is the temperature where water vapour condenses into liquid water 3. The allowable water content of diver’s breathingair is shown below in Tables B and C:Diver’s breathing gas standard and the frequency of examination and testsHSE information sheet1 of 5 pagesTable B Water vapour content of high pressure breathing airNominal maximum supply pressure Maximum water content of air at atmospheric pressure40 to 200 bar Less than or equalto 50 mg m-3 Greater than 200 bar Less than or equalto 35 mg m-3Compressors used for charging high pressure cylinders greater than 200 bar Less than or equal to 25 mg m-3Water vapour content for breathingair supplied at pressure up to 40 barThe maximum water content of air supplied at 40 bar and below, ie low pressure air compressor supplies for surface supplied diving equipment and compression chambers is provided in Table C below:Table C Water vapour content for breathing air up to 40 barNominal maximum supply pressure (bar)Maximum water content of air at atmospheric pressure and 20 °C mg m-3529010160151102080256530554050Other methods of establishing the maximum permitted water content have been developed. The details are outside the scope of this DVIS, but can be obtained from HSE Research Report 427 Moisture levels in compressed breathing air6. Standards for divers’ breathinggas – oxygen and nitrogengas mixtures (nitrox)The standards for breathing mixtures of oxygen and nitrogen in BS EN 12021:20142 are detailed inTable D:Table D Composition of oxygen and nitrogen mixesComponent Concentration at1013mb and 20 °COxygen mixes containing<20% by volume≥20% by volume(Stated a +/- 0.5b)%(Stated a +/- 1.0b)%) Nitrogen RemainderWater ≤ 15 mg m -3Carbon Dioxide≤ 5 ml m -3 (ppm) Carbon Monoxide≤ 3ml m -3 (ppm)Oil≤ 0.1 mg – m-3Total volatile non-substituted hydrocarbons(vapour or gas) asmethane equivalent≤ 30 ml m -3Other non-toxic gases c< 1%a Percentage as stated by the supplierb Tolerance value is a percentage of the total gas mixturec These gases include argon and all other noble gasesTable D is applicable to oxygen and nitrogen mixtures provided by industrial gas suppliers.Nitrox mixtures may also be generated by diving contractors themselves using membrane systems, decanting/gas booster systems, or other methods to produce nitrogen depleted air and oxygen enriched air.Health and SafetyExecutive2 of 5 pagesStandards for divers’ breathing gas – oxygen and helium gas mixtures (heliox)The standards for breathing mixtures of oxygen and helium in BS EN 12021:20142 are detailed in Table E:Table E Composition of oxygen and helium mixesComponent Concentration at1013mb and 20 °C Oxygen mixes containing≤ 10% by volume10% to ≤ 20% by volume ≥20% by volume (Stated a +/- 0.25 b)% (Stated a +/- 0.5 b)% (Stated a +/- 1.0 b)%Helium RemainderWater ≤ 15 mg m-3Carbon Dioxide≤ 5 ml m-3 (ppm) Carbon Monoxide≤ 0.2 ml m-3 (ppm)Oil≤ 0.1 mg m-3Total volatile non-substituted hydrocarbons(vapour or gas) asmethane equivalent≤ 30 ml m-3 (ppm)Hydrogen≤ 10 ml m-3 (ppm) Other non-toxic gases c< 0.5%a Percentage as stated by the supplierb Tolerance value is a percentageof the total gas mixturec These gases include argon andall other noble gasesNitrogen, water and carbon dioxide content applicable to diver gas recovery (reclaim) system compressor samplesThe standards for breathing mixtures of oxygenand helium in Table E above are fully applicable to the heliox mixtures provided for saturation diving operations by industrial diving gas suppliers. It is recognised that heliox mixtures found within diver gas recovery (reclaim) systems may have higher levels of moisture, nitrogen and carbon dioxide content than the maximum levels specified inTable E. NitrogenIn common with most gases, the physiological effects of nitrogen are related to its partial pressure at the depth it is being inhaled. A maximum of 5% nitrogen content in reclaim gases for depths up to 350 m would be acceptable.Water contentThere is a risk that increased moisture levels may lead to increased corrosion rates inside pressure vessels and pressurised pipework. Where pressure vessels and pressurised pipework are likely to contain higher levels of moisture than the maximum levels specified in Table E (eg inside reclaim systems), it is important for diving contractors to have arrangements in place to ensure that suitable examination, testing and certification of all such plant and equipment is periodically undertaken at an appropriate frequency. The increased moisture content within reclaim system gas is unlikely to cause internal freezing of regulators and valves etc when gas expands through the system. This is because reclaim systems are not high pressure systems and, in addition, the Joule-Thompson effect means that heliox does not cool on expansion. Nevertheless, the provision of heated gas supplies should also be considered when diving is carriedout in cold waters. Divers breathing gas will require active heating for dives deeper than 150 meters. When operating using breathing gas suppliedfrom a gas recovery (reclaim) system themaximum water vapour content of diver’sbreathing gas is shown in Table F.Table F Water vapour content for reclaimsystem breathing gas up to 40 barNominalmaximum supplypressure (bar)Maximum water contentof reclaim system gasat atmospheric pressureand 20 °C mg m-3104101528020200251753014540110Note: Reclaim gas based on dewpoint of 0 °C3 of 5 pagesCarbon dioxideThe source for diver reclaim make-up gas should comply with the requirements of BS EN 12021:2014 for carbon dioxide levels. The circulating gas supply within the reclaim system should be operated to minimise the carbon dioxide levels. Carbon dioxide levels within the circulating gas of diver reclaim systems should normally be limited to a maximum partial pressure of 5 mbar at the depth of the diver (ie 5000 ml m-3 (ppm) when the diver is on the surface, corresponding to 0.5% SEV (surface equivalent value)). With the exceptions of nitrogen, water vapour and carbon dioxide the standards for breathing mixtures of oxygen and helium in Table E should be applied to saturation diving diver reclaim systems. Other contaminantsA risk assessment should be carried out to establish if any other contaminants should be tested for in addition to those specified in BS EN 12021:20142. Compressor lubricant safety data sheet and/or the compressor manufacturer’s operation and maintenance manuals should be checked to seeif there are any specific substances that shouldbe tested for. In addition, the location of the compressor inlet should be checked in order to ensure that contaminated gas is not drawn in. Ifyou do identify potential sources of contamination (such as ventilation exhausts) and cannot re-locate the compressor inlet, then you should determinethe likely contaminants. If there is any doubt, additional tests for the likely contamination andmore frequent tests may be necessary.For UK application, where the gas is to be used for breathing at ambient pressures greater than 10 bar and/or periods in excess of 8 hours, the calculations given in EH 75/2 Occupational exposure limits for hyperbaric conditions should be applied to take account of the increased pressure and/or duration. Frequency of testsA competent person (see Note 2) should carry out the breathing gas tests. The purpose of periodic testingis to make sure that the control measures you have put in place are delivering the gas quality required by BS EN 12021:20142 (as required by the appropriate tables above). The frequency of tests should be based on a risk assessment, but tests shouldtake place at least every three months where the source of the divers’ breathing gas is a compressor system (including a reclaim compressor system unless deemed ‘oil free’ by the original equipment manufacturer), and more often when the quality ofthe breathing gas cannot be assured to these levels.Additional methods of assuring gas quality Monitor filter life by measuring running hoursor the volume of cylinders filled. Both of these methods rely on the contamination not exceedingthe levels assumed by the manufacturer in settingthe recommended hours or throughput.A more reliable method of assurance is for continuous in-line gas quality monitoring.One technique is to continuously monitor the moisture content of the filter cartridge. Filter cartridges are usually designed so that the drying element becomes saturated before there is any deterioration of the other elements. Monitoring the moisture content of the gas at the filter outlet can indicate when the filter has reached the end of its life.Carbon monoxide (CO) can be produced within a compressor as a result of breakdown of the lubricating oil caused by pyrolysis (chemical decomposition by heat). Pyrolysis can occur when the system is hot,but not necessarily overheating and the resulting short term high levels of CO would not necessarily be identified during periodic sampling. To minimise this hazard a CO catalyst in the filter system and/or online monitoring for CO content should be considered.Do not modify any filtration systems or compressors without seeking advice from the compressor and/or filter manufacturer.Checking contents of breathing mixtures Experience shows that it is possible for a gas mixture to be supplied which does not correspondto thecylinder markings. All diving breathing mixtures should be checked on receipt and re-checked immediately prior to connecting them to a diving gas supply or breathing apparatus charging system. Notes1 Workplace Exposure Limits (WELs) are Occupational Exposure Limits (OELs) set under COSHH,3 in order to help protect the healthof workers.2 A ‘competent person’ is a person having a combination of training, knowledge and experience that will mean they can do the job required in asafe and efficient manner, using the test apparatus provided for the task. The duty holder will haveto decide who the ‘competent person’ will be.3 Where the apparatus is used and stored at a known temperature the pressure dew point shallbe at least 5°C below the likely lowest temperature.4 of5 pagesWhere the conditions of usage and storage ofany compressed air supply is not known the pressure dew point shall not exceed -11°C References1 EH40/2005 Workplace Exposure Limits: Containing the list of workplace exposurelimits for use with the Control of Substances Hazardous to Health Regulations 20022 BS EN 12021:2014 Respiratory equipment – Compressed gases for breathing apparatus3 The Control of Substances Hazardousto Health Regulations 20024 Control of substances hazardous to health (Sixth edition). The Control of Substances Hazardous to Health Regulations 2002 (as amended). Approved Code of Practice and guidance L5 (Sixth edition) HSE Books 2013 ISBN 978 0 7176 658225 EH 75/2 Occupational exposure limits for hyperbaric conditions : Hazard assessment document HSE Books 2000 ISBN 978 0 7176 1899 66 HSE Research Report 427 Moisturelevels in compressed breathing air7 Respiratory protective equipment at work – a practical guide HSG 53: (Fourth edition) HSEBooks 2013 ISBN 978 0 7176 6454 2Further readingCommercial diving projects inland/inshore. Divingat Work Regulations 1997. Approved Code of Practice and guidance L104 (Second edition)HSE Books 2014 ISBN 978 0 7176 6593 8/pubns/books/l104.htmCommercial diving projects offshore. Divingat Work Regulations 1997. Approved Code of Practice and guidance L103 (Second edition)HSE Books 2014 ISBN 978 0 7176 6592 1/pubns/books/l103.htm Recreational diving projects. Diving at Work Regulations 1997. Approved Code of Practiceand guidance L105 (Second edition)HSE Books 2014ISBN 978 0 7176 6594 5/pubns/books/l105.htmMedia diving projects. Diving at Work Regulations 1997. Approved Code of Practice and guidance L106 (Second edition) HSE Books 2014 ISBN 978 0 7176 6595 2 /pubns/books/l106.htm Scientific and archaeological diving projects. Diving at Work Regulations 1997. Approved Code of Practice and guidance L107 (Second edition) HSE Books 2014 ISBN 978 0 7176 6596 9/pubns/books/l107.htmThe Diving at Work Regulations 1997 SI 1997/2776 The Stationery Office 1997 ISBN 0 11 065170 7Are you involved in a diving project at work? A brief guide to complying with health and safety law. Leaflet INDG266(rev 2) /pubns/indg266.htm Further informationFor information about health and safety, or to report inconsistencies or inaccuracies in this guidance, visit /. You can view HSE guidance online and order priced publications from the website. HSE priced publications are also available from bookshops. This guidance is issued by the Health and Safety Executive. Following the guidance is not compulsory, unless specifically stated, and you are free to take other action. But if you do follow the guidance you will normally be doing enough to comply with the law. Health and safety inspectors seek to secure compliance with the law and may refer to this guidance.This leaflet is available at:/pubns/dvis9.pdf.© Crown copyright If you wish to reuse this information visit /copyright.htm for details. First published 01/18.5 of 5 pagesPublished by the Health and Safety Executive DVIS9(rev2) 01/18。
富羧酸基团的共轭微孔聚合物:结构单元对孔隙和气体吸附性能的影响
富羧酸基团的共轭微孔聚合物：结构单元对孔隙和气体吸附性能的影响姚婵;李国艳;许彦红【摘要】共轭微孔聚合物(CMPs)骨架中的孔和极性基团对聚合物的气体吸附性能起着重要作用.阐明聚合物中极性基团的效果对该领域的进一步发展是必不可少的.为了解决这个根本问题,我们使用最简单的芳香系统-苯作为建筑单体,构筑了两个新颖的富羧酸基团的CMPs (CMP-COOH@1,CMP-COOH@2),并探讨了CMPs中游离羧酸基团的量对其孔隙、吸附焓、气体吸附和选择性的深远影响.CMP-COOH@1和CMP-COOH@2显示的BET比表面积分别为835和765 m2·g-1.这两种聚合物在二氧化碳存储方面显示了高潜力.在273 K和1.05 x 105 Pa条件下,CMP-COOH@1和CMP-COOH@2的CO2吸附值分别为2.17和2.63 mmol·g-1.我们的研究结果表明,在相同的条件下增加聚合物中羧基基团的含量可以提高材料对气体的吸附容量和选择性.%Polar groups in the skeletons of conjugated microporous polymers (CMPs) play an important role in determining their porosity and gas sorption performance.Understanding the effect of the polar group on the properties of CMPs is essential for further advances in this field.To address this fundamental issue,we used benzene,the simplest aromatic system,as a monomer for the construction of two novel CMPs with multi-carboxylic acid groups in their skeletons (CMP-COOH@1 and CMP-COOH@2).We then explored the profound effect the amount of free carboxylic acid in each polymer had on their porosity,isosteric heat,gas adsorption,and gas selectivity.CMP-COOH@1 and CMP-COOH@2 showed Brunauer-Emmett-Teller (BET) surface areas of835 and 765 m2·g-1,respectively,displaying high potential for carbon dioxide storage applications.CMP-COOH@1 and CMP-COOH@2 exhibited CO2 capture capabilities of 2.17 and 2.63 mmol·g-1 (at 273 K and 1.05 x 105 Pa),respectively,which were higher than those of their counterpart polymers,CMP-1 and CMP-2,which showed CO2 capture capabilities of 1.66 and 2.28 mmol·g-1,respectively.Our results revealed that increasing the number of carboxylic acid groups in polymers could improve their adsorption capacity and selectivity.【期刊名称】《物理化学学报》【年(卷),期】2017(033)009【总页数】7页(P1898-1904)【关键词】共轭微孔聚合物;羧酸;孔;气体吸附;选择性【作者】姚婵;李国艳;许彦红【作者单位】吉林师范大学,环境友好材料制备和应用教育部重点实验室,长春130103;吉林师范大学,环境友好材料制备和应用教育部重点实验室,长春130103;吉林师范大学,环境友好材料制备和应用教育部重点实验室,长春130103;吉林师范大学,功能材料物理与化学教育部重点实验室,吉林四平136000【正文语种】中文【中图分类】O647Carbon dioxide is one of the main greenhouse gases that cause global issues, such as climate warming and increases in sea level and oceanacidity. Modern climate science predicts that the accumulation of greenhouse gases in the atmosphere will contribute to an increase ins urface air temperature of 5.2 °C between the years 1861 and 2100. Carbon capture and sequestration (CCS), a process of CO2 separation and concentration can contribute to solve. For this aim, the use of porous materials tailored for selective CO2 absorption is energetically efficient and technically feasible. Among the numerous and diversified examples of novel porous materials, such as metal-organic frameworks1,2, zeolites3,4, and purely organic materials5,6 are a class of porous organic materials that allow an elaborate design of molecular skeletons and a fine control of nanopores.Conjugated microporous polymers (CMPs) are a unique class of porous organic materials that combine π-conjugated skeletons with permanent nanopores7–10, which is rarely observed in other porous polymers. CMPs have emerged as a powerful platform for synthesizing functional materials that exhibit excellent functional applications, such as heterogeneous catalysts11,12, guest encapsulation13–15, super-capacitive energy storage devices16,17, light-emitting materials18,19, and fluorescent sensors20,21 and so on. Recently, CMPs have emerged as a designable material for the adsorption of gases, such as hydrogen, carbon dioxide, and methane22–24. Although great achievements in synthesizing CMPs have been realized, extremely high Brunauer-Emmet-Teller specific surface areas as high as 6461 m2·g−125, the other pore parameters, such as pore volume, pore size, and pore size distribution, are important in determining the gas sorptionperformance26,27. Moreover, previous work has shown the surface modification of porous polymers with polar group can significantly enhance their CO2 binding energy, resulting in enhancement in CO2 uptake and/or CO2 selectivity28–30. Carboxylic-rich framework interaction is expected due to hydrogen bonding and/or dipole-quadrupole interactions between CO2 and the functional groups of porous polymers31,32. Cooper et al.33,34 reported increasing the heat of adsorption through the introduction of tailored binding functionalities could have more potential to increase the amount of gas adsorbed. Their results demonstrated that carboxylic groups functionalised polymer showed the higher isosteric heat of sorption for CO2. Torrisi et al.35 predicted that the incorporation of carboxylic groups would lead to the higher isosteric heat, challenging the current research emphasis in the literature regarding amine groups for CO2 capture.Herein, we report the synthesis and characterization two high carboxylic groups of porous polymers and investigate their performances in CO2 storage application under high pressure and cryogenic conditions (Scheme 1, CMP-COOH@1 and CMP-COOH@2). The CMPs are highly efficient in the uptake of CO2 by virtue of a synergistic structural effect, and that the carboxylic units improve the uptake, the high porosity provides a large interface, and the swellable skeleton boosts the capacity.1,3,5-Triethynylbenzene (98%) was purchased from TCI, 2,5-dibromobenzoic-3-carboxylic acid (97%) and 2,5-dibromoterephthalicacid(97%) were purchased from Alfa. Tetrakis(4-ethynylphenyl)methane was synthesized according to the literature36. Tetrakis(triphenylphosphine)palladium(0), copper(I) iodide (CuI) andtetra(4-bromophenyl)methane (97%) were purchased from Aladdin. N,N-Dimethylformamide (DMF) (99.9%), triethylamine (99%), methanol (95%) and acetone (95%) were purchased from Aladdin.1H NMR spectra were recorded on Bruker Avance III models HD400 NMR spectrometers, where chemical shifts (δ) were determined with a residual proton of the solventas standard.Fourier transform Infrared (FT-IR) spectra were recorded on a Perkin-Elmer spectrum one model FT-IR-frontier infrared spectrometer.The UV-visible analyzer was used for shimadzu UV-3600. Field-emission scanning electron microscopy (FE-SEM) images were performed on a JEOL model JSM-6700 operating at an accelerating voltage of 5.0 kV. The samples were prepared by drop-casting a tetrahydrofunan (THF) suspension onto mica substrate and then coated with gold.High-resolution transmission electron microscopy (HR-TEM) images were obtained on a JEOL model JEM-3200 microscopy.Powder X-ray diffraction (PXRD) data were recorded on a Rigaku model RINT Ultima III diffractometer by depositing powder on glass substrate, from 2θ = 1.5° up to 2θ = 60° with 0.02° increment. The elemental analysis was carried out on a EuroEA-3000. TGA analysis was carried out using a Q5000IR analyzer with an automated vertical overhead thermobalance. Before measurement, the samples were heated at a rate of 5 °C min−1 under a nitrogen atmosphere. Nitrogen sorption isotherms were measured at 77 K with ASIQ (iQ-2) volumetric adsorption analyzer.Before measurement, thesamples were degassed in vacuum at 150 °C for 12 h. The Brunauer-Emmett-Teller (BET) method was utilized to calculate the specific surface areas and pore volume. BET surface areas were calculated over the relative pressure (p/p0) range of 0.015–0.1. Nitrogen NLDFT pore size distributions were calculated from the nitrogen adsorption branch using a cylindrical pore size model. Carbon dioxide, methane and nitrogen sorption isothermswere measured at 298 or 273 K with a Bel Japan Inc. model BELSORP-max analyzer, respectively. In addition, carbon dioxide sorption isotherms were measured at 318 K and 5 × 106 Pa with a iSorb HP2 analyzer. Before measurement, the samples were also degassed in vacuum at 120 °C for more than 10 h.2.2.1 Synthesis of CMP containing carboxylic groupsAll of the polymer networks containing multi-carboxylic groups were synthesized by palladium(0)-catalyzed cross-coupling polycondensation. All the reactions were carried out at a fixed reaction temperature and reaction time (120 °C/48 h).2.2.2 Synthesis of CMP-COOH@1 and CMP-COOH@22,5-Dibromoterephthalic acid (107 mg, 0.33 mmol) and 1,3,5-triethynylbenzene (50 mg, 0.33 mmol) (CMP-COOH@1)/tetrakis(4-ethynylphenyl)methane (104 mg, 0.25 mmol) (CMP-COOH@2) were put into a 50 mL round-bottom flask, the flask exchanged three cycles under vacuum/N2. Then added to 2 mL N,N-dimethylformamide (DMF) and 2 mL triethylamine (Et3N), the flask was degassed by threefreeze-pump-thaw cycles, purged with N2. When the solution had reached reactiontemperature, a slurry of tetrakis(triphenylphosphine)palladium(0) (23.11 mg, 0.02 mmol) in the 1 mL DMF and copper(I) iodide (4.8 mg, 0.025 mmol) in the 1 mL Et3N (CMP-COOH@1)/(CMP-COOH@2) was added respectively, and the reaction was stirred at 120 °C under nitrogen for 48 h. The solid product was collected by filtration and washed well with hot reaction solvent for 4 times with THF, methanol, acetone, and water, respectively. Further purification of the polymer was carried out by Soxhlet extraction with methanol, and THF for 24 h, respectively, to give CMP-COOH@1(claybank solid, 98 mg, 94% yield), CMP-COOH@2(olivine solid, 142 mg, 90% yield). Elemental Analysis (%) Calcd. (Actual value for an infinite 2D polymer), (CMP-COOH@1) C 67.61, H 2.35. Found: C 64.84, H 2.05. (CMP-COOH@2) C 73.03, H 3.02. Found: C 70.02, H 2.19. Carboxylic-CMP was synthesized by the Sonogashira- Higihara reaction of 1,3,5-triethynylbenzene, tetrakis(4- ethynylphenyl)methane and 2,5-dibromoterephthalic acid in the presence of Pd(0) as catalyst. These two samples were unambiguously characterized by elemental analysis confirmed that the weight percentages of C and H contents are close to the calculated values expected for an infinite 2D polymer. The CMPs were further characterized by infrared spectroscopy (Fig.1). Band soft he primary bromo and borate groups of 2,5-dibromoterephthalic acid at about 598 and 1368 cm−1are absent, respectively. From 2900 to 3200 cm−1aromatic C―H stretching bands appear. A C＝C stretching mode at 1600 cm−1is also observed. All networks show the typical C≡C and COOH stretching mode at about 2200and 1700 cm−1, respectivel y, indicating the successfulincorporation of the carboxylic and alkynyl groups into the polymer materials.Field-emission scanning electron microscopy (FE-SEM) displayed that the CMPs adopt a spherical shape with sizes of 100–500 nm (Fig.2). High-resolution transmission electron microscopy (HR-TEM) revealed the homogeneous distribution of nanometer-scale pores in the textures (Fig.S1 (Supporting Information)). Powder X-ray diffraction (PXRD) revealed no diffraction, implying that all the polymers are amorphous (Fig.S2 (Supporting Information)). The TGA results show that the polymers have a good thermal stability, and the thermal degradation temperature is up to ca. 300 °C (Fig.S3 (Supporting Information)). The weight loss below 100 °C is generally attributed to the evaporation of adsorbed water and gas molecules trapped in the micropores.The conjugated polymer networks were dispersed in THF to obtain UV/Vis spectra (Fig.S4 (Supporting Information)). The polymer CMP-COOH@1 shows mainly one wide absorption peak at about 396 nm. Compared to monomer 1,3,5-triethynylbenzene, with narrow absorption maxima at 305 nm, the polymer networks exhibit a large bathochromic shift of around 111 nm. CMP-COOH@2 show similar phenomenon, compared totetrakis(4-ethynylphenyl)methane monomer, with absorption maxima at 325 and 345 nm, the polymer frameworks display a large bathochromic shift of around 68 and 48 nm, respectively. This indicates the effective enlargement of the π-conjugated system through the polycondensation reaction.The porosity of the polymer networks was probed by nitrogen sorption at 77 K. According to the IUPAC classification37, adsorption/desorption isotherms of two polymers showed mainly a type I isotherms. As seen in Fig.3(a), remarkably, the two polymer samples exhibit a steep uptake at a relative pressure of p/p0 < 0.1, suggesting that these samples have micropores. There is a sharp rise in the isotherm for the CMP-COOH@1 at higher relative pressures (p/p0 > 0.8), which indicates the presence of meso/macropores in the samples. These textural meso/macropores can be also found in the corresponding FE-SEM images (Fig.2(a)). However, the shape of the isotherm for the CMP-COOH@2 is significantly different from that of CMP-COOH@1, which displays a significant H2 type hysteresis loop in the desorption branch, characteristic of nanostructured materials with a mesoporous structure (Fig.3(a)). These meso/macropores can be ascribed mostly to interparticulate porosity that exists between the highly aggregated nanoparticles38.The pore size distribution calculated from nonlinear density functional theory (NLDFT) shows that the two polymer networks have relatively broad pore size distribution (Fig.3(b)). CMP-COOH@1 and CMP-COOH@2 showed apparent peaks in the size range 0–2 nm, whereas small fluctuations can be observed at 2–12 nm regions. The pore size distribution curves agree with the shape of the N2 isotherms (Fig.3(a)) and imply the presence of both micropores and mesopores in the two polymers. The contribution of microporosity to the networks can be calculated as the ratio of the micropore volume (Vmicro), over the totalpore volume (Vtotal). The microporosities of CMP-COOH@1 and CMP-*******************%and52.3%,respectively.Thisresultindicates that the two carboxylic networks are predominantly microporous. In addition, the BET surface area of CMP-COOH@1 and CMP-COOH@2 were calculated to be 835 and 765 m2·g−1 in the relative pressure range 0.015–0.1, respectively. The decreased surface area of CMP-COOH@2 compared to CMP-COOH@1 could be due to the CMPs constructed with longer connecting struts have lower BET surface areas39,40.In view of the fact that the CMPs possess two key properties generally associated with high CO2 uptake capacity, e.g., good porosity and abundant COOH sites, the CO2 adsorption of the polymers were investigated up to 1.05 × 105 Pa at both 298 K and 273 K (Fig.4(a, b)), respectively. Remarkably, CMP-COOH@1 and CMP-COOH@2 showed the CO2 adsorption capacities of 1.61 and 1.92 mmol·g−1 at 298 K and 1.05 × 105 Pa, respectively (Fig.4(a)). When the temperature was elevated to 273 K, the polymers CMP-COOH@1 and CMP-COOH@2 displayed the higher CO2 capture of 2.17 and 2.63 mmol·g−1(Fig.4(b)), respectively, which were comparable to that of other microporous hydrocarbon networks41. Despite CMP-COOH@2 with a lower surface area, but which adsorbed more CO2 probably due to it has a higher pore volume. In addition, the isosteric heat of adsorption (Qst) of the polymers was calculated from the CO2 uptake data at 273 K and 298 K by using Clausius-Clapeyron equation (Fig.4(c)). The two polymer networks show the isosteric heats of CO2 adsorption around 35.5 and 30.9 kJ·mol−1. Because there is less carboxylicacid in the structural unit, the CO2Qst of CMP-COOH@2 is lower than that of CMP-COOH@1, which is consistent with that of the previous reported polymers33,34. Moreover, the high pressure CO2 sorption properties of the two polymers were also investigated at 5 × 106 Pa and 318 K. As seen in Fig.4(d), CMP-COOH@1 and CMP-COOH@2 show a nearly linear increase with the increasing pressure no obviously turning point. CMP-COOH@1 and CMP-COOH@2 show the higher CO2 capture capacity of 498 and 434 mg·g−1 at 318 K and 5 × 106 Pa, respectively (Fig.4(d)). These results indicated that the CO2 uptake in these networks at high pressures is not dependent solely on the surface area, pore volume or polar groups in the skeletons, but also the measuring pressure have a large effect on the uptake of gas.In order to investigate the amount of carboxylic group in the network whether affects CO2 adsorption capacity of polymers. We synthesized another two carboxylic conjugated polymer with relatively low amount of carboxylic groups (scheme S1, CMP@1 and CMP@2 (Supporting Information)) based on 2,5-dibromobenzoic acid, 1,3,5-triethynylbenzene and tetrakis(4-ethynylphenyl)methane. They show the BET surface area of 979 and 876 m2·g−1 (Fig.S5 (Supporting Information)), respectively, which is higher to that of counterpart CMP-COOH@1 and CMP-COOH@2. CMP@***********************************–2.0 nm (Fig.S6 (Supporting Information)). The decreased surface area of CMP-COOH@1 compared to CMP@1 could be due to the volume of 2,5-dibromoterephthalic acid in CMP-COOH@1 is obviously larger than 2,5-dibromobenzoic acid in CMP@1, which made the bulky benzen–carboxylic **************************************************** phenomenon can be also observed in CMP-COOH@2 and CMP@2 system. As shown in Fig.4(b), at 273 K and 1.05 × 105 Pa, polymers C MP@1 and****************************************.28mmol·g−1, respectively. The CO2 uptake value of CMP-COOH@1 and CMP-COOH@2 is 1.31 and 1.15-times that of the counterpart CMP@1 and CMP@2, respectively, indicating that increasing amount of carboxylic groups in the CMP networks can improve CO2 uptake. In addition, we calculated the isosteric heats of these polymers, they showed the following order (Fig.4(c)):CMP-COOH@1>CMP-COOH@2>CMP@1>************* there is less carboxylic groups in the structural units of CMP@1 andCMP@2, the CO2Qst of CMP@1 and CMP@2 is lower than that of CMP-COOH@1 and CMP-COOH@2, respectively33,42. In addition, CMP-COOH@1 and CMP-COOH@2 show the higher CO2 capture capacity than that of CMP@1 (447 mg·g−1) and CMP@2 (402 mg·g−1) at 318 K and 5 × 106 Pa, respectively (Fig.4(d)). These results imply the amount of carboxylic groups effects BET surface area, pore volume and isosteric heats lead to different the uptake of gas.As for carbon dioxide capture, high separation properties towards CH4 and N2 are also necessary and important in gas separation applications. In order to investigate the gas adsorption selectivity of the microporous polymer networks, CO2, N2, and CH4 sorption properties were measured by volumetric metho ds at 273 K and 1.05 × 105 Pa. It was found that thetwo porous polymer networks show significantly higher CO2 uptake ability than N2 and CH4 in the whole measurement pressure range (Fig.S7 (Supporting Information)). CO2/CH4 and CO2/N2 selectivity was first evaluated by using the initial slope ratios estimated from Henry′s law constants for single-component adsorption isotherms. The CO2/CH4 selectivityofCMP-COOH@********************************** and 6.2, respectively (Table S1 and Fig.S8 (Supporting Information)). In addition, two polymers exhibited the CO2/N2 adsorption selectivity is 48.2 and 39.5, respectively (Table S1 and Fig.S9 (Supporting Information)). Meanwhile, the gas selective capture was also supported by the results from the ideal adsorbed solution theory (IAST), which has been widely used to predict gas mixture adsorption behavior in the porous materials43,44. Under simulated natural gas conditions (CO2/CH4, 50/50), the experimental CO2 and CH4 isotherms collected at 273 K for carboxylic CMP were fitted to the dual-site Langmuir model and the single-site Langmuir model, respectively (Fig.S10 (Supporting Information)). The calculated IAST data for carboxylic CMP are shown in Table S1. At 273 K and 1.05 × 105 Pa, CMP-COOH@1 and CMP-COOH@2 exhibit an appreciably high selectivity of CO2 over CH4 under natural gas conditions (5.5 and 5.2) (Fig.S10 (Supporting Information)), which is comparable to some reported MOPs, such as A6CMP (5.1) 45, SCMP (4.4–5.2) 30, and P-G1-T (5) 46. Furthermore, the CO2/N2 adsorption selectivities for CMP-COOH@****************************************.8at273K and 1.05 × 105 Pa (Table S1 and Fig.S11 (Supporting Information)),respectively, which is comparable to some reported MOPs, such as ALP-1(35) 38, PCN-TA (33) 47, and PCN-DC (48) 47. These excellent CO2 selective capture performance of carboxylic CMPs evaluated by IAST are consistent with the results calculated from the initial slopes method. In addition, in light of the amount of carboxylic group effect for the uptake of gas, we reasoned that it might be effective for CO2/CH4 and CO2/N2 separations. At 273 K and 1.05 × 105 Pa, CMP@1 and CMP@2 exhibit the selectivities of CO2/CH4 (4.7 and 4.1) and CO2/N2 (32.1 and 30.5) under natural gas conditions via the IAST method (Figs.S10 and S11 (Supporting Information)), respectively, which are lower that of counterpart CMP- COOH@************************************************* carboxylic groups effects selectivity of polymers. These data implys that increasing the amount of carboxylic unit of polymers can improve the adsorption capacity and selectivity of the materials, which suggested the possibility for the surface properties of microporous polymers to be controlled to interact with a specific gas by post-modification.In summary, two carboxylic CMPs with relatively high surface area have been synthesized. The clean energy applications of the polymers have also been investigated and it was found that CMP-COOH@1 and CMP-***********************.63mg·g−1 of carbon dioxide at 1.05 × 105 Pa and 273 K, respectively, which can be competitive with the reported results for porous organic polymers under the same conditions. The free carboxylicacid functionalized polymers show that increasing the amount of carboxylic group of polymers can improve the adsorption capacity andselectivity of the materials under the same conditions, which is a promising candidate for the separation and purification of CO2 from variousCO2/CH4 mixtures such as natural gas and land-fill gas by adsorptive processes.Supporting Information: available free of charge via the internet at.【相关文献】(1) Sumida, K.; Rogow, D. L.; Mason, J. A.; McDonald, T. M.; Bloch, E. D.; Herm, Z. R.; Baeand, T. H.; Long, J. R. Chem. Rev.2012,112, 724. doi: 10.1021/cr2003272(2) Suh, M. P.; Park, H. J.; Prasad, T. K.; Lim, D. W. Chem. Rev. 2012,112, 782. doi:10.1021/cr200274s(3) Coudert, F. X.; Kohen, D. Chem. Mater.2017,29, 2724. doi:10.1021/acs.chemmater.6b03837(4) Jensen, N. K.; Rufford, T. E.; Watson, G.; Zhang, D. K.; Chan, K. I.; May, E. F. J. Chem. Eng. Data2012, 57, 106. doi: 10.1021/je200817w(5) Tan, L.; Tan, B. Chem. Soc. 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地上部氮累积量英文
地上部氮累积量英文英文回答：Aboveground nitrogen accumulation (ANA) comprises the total amount of nitrogen stored in aboveground plant biomass, which includes leaves, stems, flowers, and branches. ANA plays a vital role in ecosystem functioning, influencing nutrient cycling, carbon sequestration, and plant productivity. The accumulation of nitrogen in aboveground biomass is primarily driven by nitrogen uptake from the soil and atmospheric deposition.ANA can be measured through various methods, such as destructive harvesting and biomass sampling. Destructive harvesting involves collecting and measuring the weight of aboveground biomass, while biomass sampling involves estimating the biomass using allometric equations or other techniques. These methods provide valuable data for monitoring changes in ANA over time and assessing the impact of environmental factors on nitrogen accumulation.Quantifying ANA is crucial for understanding ecosystem dynamics. High ANA indicates a healthy and productive ecosystem with efficient nitrogen cycling. Conversely, low ANA may reflect nutrient deficiencies, environmental stresses, or disturbance events. By studying ANA, researchers can gain insights into the nitrogen status of ecosystems and make informed decisions about land management practices.In natural ecosystems, ANA varies across different plant communities and biomes. For example, foreststypically have higher ANA compared to grasslands due to their larger biomass and longer lifespans. Wetlands and riparian zones also exhibit substantial ANA due to the presence of nitrogen-fixing plants and high soil moisture. Understanding the factors that influence ANA is essential for predicting ecosystem responses to environmental changes and ensuring the sustainable management of natural resources.中文回答：地上部氮累积量。
肝脏少见恶性肿瘤影像
影像特点
Positron emission tomography (PET) using deoxyglucose (FDG) scan has been performed for further evaluation FDG–PET/CT showed diffuse intense FDG uptake in the enlarged liver and spleen, with systemic FDG-avid lymphadenopathy including the hepatic hilar nodes
There are three morphologic patterns in hepatic lymphoma:
large solitary masses (>4 cm), multiple focal nodules diffuse infiltrative type.
Hepatic lymphoma appears as low-density lesions on unenhanced and contrast-enhanced CT scans, or has a thin enhancing rim . The CT characteristics of hepatic secondary lymphoma include blood vessel floating sign and enhancement
However, none of the imaging findings is specific for hepatic lymphoma.
影像特点
资料整理
• 仅供参考,用药方面谨遵医嘱
影像特点
根据ＰＨＡ的生长方式将其分为４种 多发结节型、单发巨块型、巨块及结节混合 型、弥漫浸润性微结节型。
维库溴胺和顺苯磺酸阿曲库胺的比较
COMPARATIVE STUDY OF NEUROMUSCULARBLOCKING AND HEMODYNAMIC EFFECTSOF ROCURONIUM AND CISATRACURIUMUNDER SEVOFLURANE OR TOTALINTRAVENOUS ANESTHESIAa Shraf M oUnir a Min*, M ohaMMad y oSry M ohaMMad*and M ona f a Thi i brahiM*AbstractNeuromuscular blockers (NMB) are important adjuvant to general anesthesia. Rocuronium bromide and cisatracurium besylate are considered relatively recently introduced non-depolarizing muscle relaxants.Objectives: This study evaluates the enhancement of cisatracurium and rocuronium-induced neuromuscular block during anesthesia with 1.5 MAC sevoflurane or total i.v. anesthesia (TIV A), hemodynamic effects and side effects.Methodology: 80 patients were randomly allocated into one of four equal Groups to receive either rocuronium (under sevoflurane or propofol TIV A) or cisatracurium (under sevoflurane or propofol TIV A). The NMB effects of rocuronium and cisatracurium were studied by constructing dose-effect curves. Acceleromyography (TOF-Guard) and train-of-four (TOF) stimulation of the ulnar nerve were used (2 Hz every 15 sec). Cisatracurium and rocuronium were administered inincrements until depression of T1/T> 95% was reached. Hemodynamic effects of both musclerelaxants together with sevoflurane or propofol were assessed using thoracic bioimpendance.Results: Depression of T1/Twas enhanced under sevoflurane compared to TIV A. ED50andED95 values of both drugs were significantly lower under sevoflurane more than TIV A. Recoveryindex 25-75% and time to a TOF ration of 0.70 were prolonged significantly by sevoflurane compared to TIV A. Hemodynamically, rocuronium and cisatracurium did not exert significant changes, but the interaction of the relaxants and the anesthetic agents resulted in statistically significant decline in some hemodynamic parameters at certain periods which are not clinically significant and required no medications.Conclusion: We conclude that the effects of rocuronium and cisatracurium are significantly enhanced during sevoflurane compared with propofol anesthesia and the recovery is lower.From Anesthesia Department, Faculty of Medicine, Cairo University.* Correspondence with Dr. Mohammad Yosry Mohammad 31 Meawen Street. East Omrania - Haram - Giza. 1st floor, flat no.3. Post code 12551 Cairo, Egypt. Phone: 002-010-168-93-92 Fax: 002-02-3761348 E-mail: m_yosry_m@39M.E.J. ANESTH 20 (1), 200940A. M. AMIN ET. ALduring anesthesia, and a centrally mediated relaxation. Not all types of anesthetics enhance neuromuscular block to the same extent 6.Inhaled anesthetics augment the neuromuscular blockade from nondepolarizing muscle relaxants in a dose-dependent fashion, which may also depend on the duration of anesthesia.Joo and Perks have shown that the use of volatile anesthetics results in lower ED50 and ED95 of neuromuscular blockade significantly in comparison to propofol 4. Underestimation of the enhancement of neuromuscular block by volatile anesthetics during short procedures could result in inadvertent prolonged duration of relaxation.A new method for monitoring neuromuscular function consists of measuring acceleration of the thumb after stimulation of a peripheral motor nerve 7. This technique is based on Newton’s second law:Force = mass x accelerationThus if mass is constant, acceleration is directly proportional to force. Accordingly, after nerve stimulation, one can measure not only the evoked force but also the acceleration of the thumb 8.Acceleromyography is a simple method of analyzing neuromuscular function. One requirement is that the muscle be able to move freely. During a nondepolarizing neuromuscular blockade, good correlation exists between the TOF ratio measured by this method and the TOF ratio measured with a force displacement transducer 9. Also the precision of acceleromyography seems to be comparable to that of mechanical measurement 10.The aim of this study is to compare rocuronium to cisatracurium regarding intensity, duration of neuromuscular blockade and also the hemodynamic profile under sevoflurane or total intravenous anesthesia with propofol, as well as associated side effects.Materials and MethodsThis clinical study was conducted in Kasr et Aini University Hospital after obtaining local Ethics Committee approval and informed patient consent. Eighty adult patients of both sexes (ASA I and II) scheduled to undergo extra-thoracic moderateIntroductionNeuromuscular blockers (NMB) have become essential parts of the anesthetist armamentarium. They aid endotracheal intubation, mechanical ventilation, reduce anesthetic requirements, prevent patient movement without voluntary or reflex muscle movement, facilitate surgery, and decrease oxygen consumption.In the development of new neuromuscular blocking drugs, the anesthesiologist is now provided with drugs that are almost free of unwanted effects, have a time course of action that allows great control of their activity and, in most cases, allows the anesthesiologist to substitute them for succinylcholine 1.In selecting a neuromuscular blocking agent, an anesthetist strives to achieve three competing goals: rapid adequate muscle relaxation, hemodynamic stability, and predictable complete return of skeletal muscle function.Rocuronium bromide is a non-depolarizing muscle relaxant, with a short onset time, an intermediate duration of action and rapid recovery characteristics coupled with cardiovascular stability, with no histamine release or other side effects 2.Cisatracurium has an intermediate duration of action, potent and safe with excellent cardiovascular stability and without apparent histamine release 3.Sevoflurane is a fluorinated methyl ethyl ether that has less respiratory irritation, more hemodynamic stability and more rapid emergence in comparison to isoflurane 4. It has a low blood-gas solubility resulting in rapid uptake and elimination. These physicochemical properties allow a fast recovery, thus making it suitable for day case surgery.Propofol (di-isopropylphenol) is a phenol which is insoluble in water. The short elimination half life and non cumulative properties of propofol should make this drug ideal for use in TIV A. Indeed propofol can be considered the best intravenous anesthetic available for TIV A 5.The neuromuscular blocking effects of muscle relaxants are enhanced by volatile anesthetics, a phenomenon called “potentiation”. Several reasons have been postulated as the causes of this potentiation: pre-junctional effects, increased blood flow to musclesM.E.J. ANESTH 20 (1), 200941NMB AGENTS & HEMODINAMIC EFFECTSkg) till the end of the operation.Neuromuscular MonitoringBy the use of TOF-guard (biometer, Denmark) the following variables of neuromuscular block were obtained for all groups:1 - Depression of T 1 of the train-of-four: Cumulative increments of 100 µg.kg -1 rocuronium were given in Groups I and III, while increments of 15 µg.kg -1 cisatracurium were given in Groups II and IV . The subsequent dose was administered after at least 3 min and only if three consecutive twitches of identical amplitude were demonstrated (steady state of onset). Increments were given until depression of the first twitch of at least 95% was achieved during sevoflurane or total i.v. anesthesia (equi-effective dose: identical end-point instead of identical doses ).2 - Cumulative dose-response curves : They were obtained by non-linear regression in the four Groups, showing values of ED 50, Ed 95, Ed 95/ED 50 ratio and the slope of the regression curve in the four Groups of the study.3 – Clinical duration : Time after injection of the last cumulative dose of muscle relaxant until 25% recovery of T 1.4 – Recovery index : Time interval during witch T 1 recovered from 25% to 75% of control. Time to TOF 0.7: Time required for return of TOF ratio to 0.7.Fig. 1The TOF-Guard connected to the patientbefore starting stimulationTOF-Guard: It is a relatively new microprocessor controlled neuromuscular transmission monitorelective general surgery were studied in a prospective, randomized study. Routine laboratory investigations included liver function tests, kidney function tests, complete blood picture, and coagulation profile.Patients were randomly divided into 4 equal groups, (20 patients each). Group I (Rocuronium & Sevoflurane), Group II (Cisatracurium & Sevoflurane), Group III (Rocurnium & Propofol) and finally, Group IV (Cisatracurium and propofol). Exclusion criteria included cardiovascular diseases or drugs affecting hemodynamics, r enal i mpairment, h epatic i nsufficiency, endocrine disease, neuromuscular disease or receiving drugs that interact with neuromuscular blockers and finally, difficult intubation patients grade III & IV .All patients received midazolam 0.05 mg.kg -1 I.M. one hour before surgery. An intravenous line was secured in the arm opposite to that connected to the neuromuscular monitoring equipment. Anesthesia was induced with propofol 2-2.5 mg.kg -1 and fentanyl 1 µg.kg -1. Oxygen and nitrous oxide mixture (50:50%) were used in all Groups. Groups I and II patients were allowed to sustain spontaneous ventilation with a face mask with 2 MAC sevoflurane for 10-15 minutes, then rocuronium and cisatracurium were given in gradual incremental doses till reaching ED 95 as judged by accelerograph. Groups III and IV patients received a standard propofol infusion at 6-12 mg.kg -1.h -1. Rocuronium and cisatracurium were given in gradual incremental doses till reaching ED 95 as judged by accelerograph. The patients were anesthetized before operating the stimulator, as the stimulator could be painful to an awake patient.Lungs were mechanically ventilated, followed by laryngoscopy and orotracheal intubation when ED 95 was reached. Anesthesia was maintained in Group I and II with 2 MAC sevoflurane and with propofol, 100 µg.kg -1.min -1 in Groups III and IV . End-tidal PCO 2 was adjusted to 32-36 mmHg, skin temperature above the monitored muscle were measured and maintained between 32°C and 35°C by passive warning (wrapping of the patient arm in a cotton blanket). The arterial pressure cuff was placed on the opposite arm.When adductor response was reached to T 25% (time to recovery of T 1 to 25% of baseline), clinical relaxation was maintained by a second bolus ofrocuronium (0.1 mg/kg) or cisatracurium (0.015 mg/42Statistical AnalysisData were presented as mean (SD), or mean (95% CI), as appropriate. Statistical analysis was performed using the software package statistica ® 5.0 for Windows ®. Values were compared among the groups using analysis of variance (ANOV A) with post hoc Newman-Keul’s test. Repeated measures ANOV A were used for comparison of hemodynamic parameters. Chi-square test was used for analysis of categorical data. Statistical significance was set when P < 0.05. Dose-response curves were constructed by non-linear regression using the known pharmacological model:Response = Max - MaxMax + (Dose /ED 50)SlopeWhere Max is the maximum possible response (100% in the present case), ED 50 is the median effective dose and Slope is the slope of the regression curve. Both ED 50 and Slope were estimated as regression parameters. ED 95, the dose which produces the desired response in 95% of patients, was calculated from the equation of the regression curve.The 95% confidence interval (CI) was calculated for ED 50, ED 95, the ratio ED 95/ED 50, and the slope of the curve. If the experiment is to be repeated a hundred times under the same conditions, the calculated values of the previously mentioned parameters will fall within the 95% CI in 95 of these hundred times; i.e. it can be said with 95% confidence that the calculated values of the parameter will fall within the 95% CI.ResultsDemographic data: there was no significant difference among the four Groups of the study as regards age, weight, gender distribution, or duration or surgery (Table 1).Hemodynamic parametersHeart rate: Changes in heart rate are shown in Table 2. Significant changes at certain times of the study are marked with *. There was no significant difference among the four Groups at baseline as well as all through the study period. General anesthetic administration resulted in a non significant decrease of heart rate in the four Groups of the study.based on accelerometry. Four supramaximal stimuli of 60 mA were given every 0.5 seconds (2HZ), and each set (train) is repeated by the monitor every 15 seconds to the unlnar nerve at the wrist. Electrodes are placed over the ulnar nerve on the medial side of the wrist. The transducer is positioned so that its flat side is placed on the finger in such a way that the movement is perpendicular. The temperature probe is placed over the skin of adductor pollicis muscle; it can read between 16.0 to 41.5 C°. The data are stored on a memory card and transferred to a computer (Fig. 1).Hemodynamics: Hemodynamic parameters were monitored at; before administration of general anesthesia, after administration of general anesthesia and just before administration of muscle relaxant, then at 1, 3, 5, 10, 15, 20 minutes after muscle relaxant and then every 10 minutes up to 90 minutes. The following parameters were monitored: heart rate, mean arterial blood pressure (by Agilent M 1166A monitor), cardiac index and stroke index were monitored non-invasively by thoracic bioimpendance (BOMED/NCCO M3-R7) cardiodynamic monitor. Electrodes are applied to the patients’ neck and chest as shown in Fig. 2. After recovery data were measured, conventional doses of neostigmine 0.045 mg/kg with atropine 0.01 mg/kg were given, followed by continued hemodynamic and oxygenation monitoring and management of postoperative complications: e.g. pain, nausea and vomiting.Fig. 2The drawing indicating proper placement of ThoracicBioimpendance electrodesA. M. AMIN ET. ALM.E.J. ANESTH 20 (1), 200943Table 1Demographic and operative data of patientsin the four Groups of the study[mean (SD) or ratio].Group I (n = 20)Group II (n = 20)Group III (n = 20)Group Iv (n = 20)Age (year)35 (8.9)34 (8.8)35 (7.8)37 (6.5)Gender (M/F)12/89/1113/711/9Weight (kg)73 (3.9)70 (5.2)73 (5.09)74 (3.9)ASA status (I/II)15/514/616/413/7Duration ofoperation (min)72 (8.8)71 (7.1)69 (5.8)74 (9.2)Mean arterial pressure: As shown in Table 3, there was no significant difference among the four Groups at baseline as well as all through the study period as regards MAP. Mean arterial pressure showed non significant decrease as a result of administration of general anesthetics. Significant changes at certain times of the study are marked with *.Table 2Heart rate (beats/min) in the four Groups of the study [mean (SD)]Group I (n = 20)Group II (n = 20)Group III (n = 20)Group Iv (n = 20)Baseline 75 (4.9)76 (5.6)76 (6.4)77 (2.8)Before MR72 (5.2)73 (6.3)71 (5.8)72 (5.5)173 (7.5)73 (6.8)72 (9.0)73 (5.5)T i m e a f t e r a d m i n i s t r a t i o n o f M R (m i n )371 (6.6)73 (6.7)71 (6.5)*71 (4.9)*572 (6.3)72 (5.3)71 (7.3)71 (3.6)*1071 (6.3)72 (5.9)71 (7.9)72 (5.3)*1572 (6.3)73 (5.9)70 (8.4)*73 (5.1)2071 (6.3)72 (8.1)73 (7.1)73 (4.8)3071 (6.3)72 (6.8)71 (9.1)*72 (4.4)*4070 (7.2)71 (6.6)71 (5.9)73 (5.0)5072 (7.5)73 (6.5)72 (7.8)72 (5.5)6070 (6.4)73 (7.0)71 (7.5)*73 (5.4)7072 (7.2)71 (6.0)71 (8.0)72 (5.0)*8070 (6.4)72 (6.4)72 (6.2)71 (3.4)*9071 (5.1)74 (6.7)71 (8.4)*71 (5.5)** P < 0.05 compared to baseline values before induction of anesthesia.Table 3Mean arterial pressure (mmHg) in the four Groups of the study[mean (SD)](n = 20)(n = 20)(n = 20)Iv (n = 20)Baseline 89 (5.3)87 (4.2)86 (4.7)89 (6.0)Before MR84 (8.4)82 (8.5)80 (6.2)83 (7.9)184 (6.5)81 (5.9)79 (6.4)*81 (7.3)*T i m e a f t e r a d m i n i s t r a t i o n o f M R (m i n )382 (7.5)*81 (7.6)*79 (5.4)*81 (7.4)*584 (8.4)82 (8.1)80 (6.2)82 (7.3)*1083 (9.5)*80 (4.1)*81 (6.3)84 (7.3)1584 (6.3)78 (6.9)*83 (5.5)84 (6.9)2085 (8.2)80 (6.8)*81 (7.4)84 (8.9)3082 (7.7)*79 (6.2)*81 (6.9)85 (7.6)4083 (8.0)*82 (7.7)81 (7.7)85 (8.6)5083 (7.1)*81 (6.8)79 (7.4)*85 (8.9)6080 (7.0)*81 (7.8)*80 (7.8)83 (7.6)7084 (7.6)80 (6.4)*79 (7.2)*83 (8.7)*8082 (8.0)*81 (8.1)80 (8.1)85 (6.4)9082 (8.2)*77 (7.4)*79 (7.6)*84 (8.6)* P < 0.05 compared to baseline values before induction of anesthesia.NMB AGENTS & HEMODINAMIC EFFECTS44degree of depression of the T 1 twitch of the train-of-four stimulation in the four Groups of the study. To reach the end-point of at least 95% depression of the T 1 twitch, all patients required at least two increments of muscle relaxants. Most patients required a third increment, while a few patients required a fourth increment. The mean depression (as percent of baseline) resulting from administration of increments of muscle relaxants are shown in Table 6. No patient in group II required a fourth increment of muscle relaxant.Table 5Stroke index (ml/m 2) in the four Groupsof the study [mean (SD)]Group I (n = 20)Group II (n = 20)Group III (n = 20)Group Iv(n = 20)Baseline 52 (6.8)53 (5.7)52 (5.1)53 (3.8)Before MR47 (8.9)49 (7.2)51 (7.0)52 (5.7)147 (7.0)50 (7.8)52 (7.2)53 (6.9)T i m e a f t e r a d m i n i s t r a t i o n o f M R (m i n )349 (7.1)49 (7.4)52 (7.0)54 (5.7)549 (7.8)49 (6.1)51 (6.9)53 (4.9)1049 (8.7)49 (7.7)53 (7.1)54 (5.8)1548 (7.8)48 (7.6)52 (8.0)52 (4.9)2047 (5.5)*47 (7.4)*50 (8.2)51 (6.7)3048 (8.5)48 (6.1)50 (6.9)52 (5.8)4047 (7.9)48 (8.2)*50 (7.2)51 (6.4)5047 (7.4)*48 (5.7)51 (6.3)52 (4.9)6047 (7.0)48 (4.7)50 (7.1)50 (4.8)7046 (6.5)*48 (6.0)51 (6.5)51 (6.6)8048 (8.3)49 (6.8)50 (5.8)53 (4.2)9047 (7.1)*48 (5.4)*51 (6.9)52 (4.5)* P < 0.05 compared to baseline values before induction of anesthesia.Cumulative dose-response curves: Figures 3 through 6 represent the cumulative dose-response curves in the four Groups of the study. The thin lines represent the 95% confidence intervals of the regression line. The narrow confidence intervals imply low inter-individual variability in the response to muscle relaxants. It can be shown from the cumulative dose-response curves that a plateau is reached as the dose approaches the ED 95. From the cumulative dose-Cardiac index (CI): As shown in Table 4, there was no significant difference among the four Groups at baseline as well as all through the study period as regards CI. CI showed non significant decrease as a result of administration of general anesthetics in all Groups. Significant changes at certain times of the study are marked with *.Table 4Cardiac index (L/min/m 2) in the four Groups of the study[mean (SD)]Group I (n = 20)Group II (n = 20)Group III (n = 20)Group Iv (n = 20)Baseline 3.4 (0.34) 3.5 (0.38) 3.4 (0.29) 3.5 (0.25)Before MR3.1 (0.45) 3.3 (0.40) 3.2 (0.35) 3.3 (0.37)1 3.1 (0.38) 3.3 (0.37) 3.2 (0.33) 3.4 (0.37)T i m e a f t e r a d m i n i s t r a t i o n o f M R (m i n )3 3.2 (0.32) 3.3 (0.45) 3.2 (0.37) 3.4 (0.37)5 3.2 (0.38) 3.2 (0.35)3.2 (0.37)3.3 (0.28)10 3.2 (0.48) 3.2 (0.49)* 3.3 (0.36) 3.5 (0.29)15 3.1 (0.37) 3.2 (0.39)* 3.2 (0.34) 3.3 (0.42)203.0 (0.32)* 3.1 (0.45)* 3.2 (0.46) 3.3 (0.40)*30 3.1 (0.35) 3.2 (0.37)* 3.1 (0.32)* 3.3 (0.31)40 3.0 (0.40)*3.1 (0.49)*3.1 (0.37)*3.3 (0.38)50 3.1 (0.39) 3.2 (0.40) 3.2 (0.34) 3.3 (0.22)60 3.0 (0.33)* 3.1 (0.37)*3.1 (0.38)*3.2 (0.30)*70 3.0 (0.30)* 3.3 (0.40) 3.2 (0.37) 3.3 (0.41)*80 3.0 (0.37) 3.2 (0.36)3.1 (0.37)3.3 (0.30)903.0 (0.38)*3.2 (0.28)* 3.2 (0.40) 3.3 (0.26)** P < 0.05 compared to baseline values before induction ofanesthesia.Stroke index (SI): As shown in Table 5, there was no significant difference among the four Groups at baseline as well as all through the study period. Stroke index showed non significant decrease after administration of general anesthetics in all Groups. Significant changes at certain times of the study are marked with*.Neuromuscular MonitoringDepression of T 1 of the train-of-four: Administration of muscle relaxants resulted in a variableA. M. AMIN ET. ALM.E.J. ANESTH 20 (1), 200945response curves, the ED 50 and the ED 95 were calculated in each of the four Groups. The values of ED 50, ED 95, the ED 95/ED 50 ratio and the slope of the regression curve in the four Groups are shown in Table 3-9, together with their 95% confidence intervals. Values of ED 50 and ED 95 in the sevoflurane Groups were significantly lower than those in the propofol Groups for each muscle relaxant.Fig. 3Cumulative dose-response curve for rocuronium in patients anesthetized with sevoflurane. Horizontal bars represent the individual observations. The thick solid line represents the best-fit regression line. The upper and the lower thinsolid lines represent the 95% confidence limits of the regression line.Cumulative Rocuronium Dose (μg/kg)Table 6Depression (%) of T 1 of the train-of-four relative to baseline values after increments of muscle relaxant in the four Groups of the study [mean (SD)].Group IGroup II Group III Group Iv Firstincrement 27 (9.2)[n = 20]36 (4.4)[n = 20]14 (4.8)[n = 20]13 (4.3)[n = 20]Second increment 90 (7.2)[n = 20]93 (2.0)[n = 20]78 (6.8)[n = 20]78 (3.9)[n = 20]Third increment 97 (1.8) [n = 15]98 (1.8)[n = 20]95 (3.1)[n = 20]90 (3.2)[n = 20]Fourth increment100 (0.0)[n = 2][n = 0]100 (1.2)[n = 6]97 (1.8)[n = 16]Fig. 4Cumulative dose-response curve for cisatracurium in patients anesthetized with sevoflurane. Horizontal bars represent the individual observations. The thick solid line represents the best-fit regression line. The upper and the lower thinsolid lines represent the 95% confidence limits of the regression line.Cumulative cisatracurium Dose (μg/kg)NMB AGENTS & HEMODINAMIC EFFECTS46However, the slope of the curve and the ED 95/ED 50 ratio were comparable among the Groups (Table 7). The cumulative dose-response curve was shifted to the left with sevoflurane anesthesia as compared toFig. 5Cumulative dose-response curve for rocuronium in patients a nesthetized with propofol. Horizontal bars represent the individual observations. The thick solid line represents the best-fit regression line. The upper and the lower thinsolid lines represent the 95% confidence limits of the regression line.Cumulative Rocuronium Dose (μg/kg)Fig. 6Cumulative dose-response curve for cisatracurium in patients anesthetized with propofol. Horizontal bars represent the individual observations. The thick solid line represents the best-fit regression line. The upper and the lower thinsolid lines represent the 95% confidence limits of the regression line.Cumulative cisatracurium Dose (μg/kg)propofol anesthesia for each of the muscle relaxants (Fig. 7 & 8). The slope of the curve was not much affected by changing the anesthetic.Table 7:Values of ED 50, ED 95, eED95/ED50 ratio and the slope of the regression curve in the four Group of the study.Group IGroup IIGroup IIIGroup Iv ED 50 (µg/kg)Mean 12417150*23†95% CI 119.9 to 128.016.8 to 17.2146.8 to 153.922.3 to 23.3ED 95 (µg/kg)Mean 23832295*46†95% CI 215.1 to 267.130.5 to 34.2276.1 to 316.243.2 to 49.0ED 95/ED 50Mean 1.92 1.90 1.96 2.0195% CI 1.68 to 2.23 1.77 to 2.04 1.79 to 2.15 1.86 to 2.20SlopeMean 4.519 4.600 4.376 4.20595% CI4.002 to5.0354.293 to 4.9074.088 to 4.6653.956 to4.453* P < 0.01 compared with group I.† P < 0.01 compared with group II.A. M. AMIN ET. ALM.E.J. ANESTH 20 (1), 200947Recovery from muscle relaxation: Time to recovery of T 1 to 25% of baseline (T 25%) was not significantly different with the different anesthetics or muscle relaxants; while time to recovery of T 1 to 75% of baseline (T 75%), the recovery index (the difference between T 75% and T 25%) and time required for return of TOF ratio to 0.7 (TOF 0.7) were significantly prolonged by the use of sevoflurane compared with propofol, and were significantly longer with cisatracurium than rocuronium (Table 8).Recorded Side EffectsThree patients in the propofol with rocuronium Group elicited pain on drugs injection and postoperative phlebitis. Also we report two cases of postoperative nausea and vomiting in the sevoflurane Groups, one in each Group.Fig. 7Comparison between the cumulative dose-response curves of rocuroniumunder sevoflurane versus propofol anesthesia.Cumulative cisatracurium Dose (μg/kg)Fig. 8Comparison between the cumulative dose-response curves of cisatracuriumunder sevoflurane versus propofol anesthesia.Cumulative cisatracurium Dose (μg/kg)Table 8Recovery criteria in the four Groups of the study [mean (SD)]Group I (n = 20)Group II(n = 20)Group III (n = 20)Group Iv (n = 20)T 25% (min)18 (4.8)19 (4.5)15 (3.3)16 (6.3)T 75% (min)31 (8.0)*37 (8.9)*†23 (5.8)30 (10.1)†Recovery index (min)13 (3.3)*18 (4.5)*†9 (2.5)14 (3.8)†TOF 0.7 (min)36 (7.8)*44 (6.4)*†29 (6.2)34 (6.7)†T 25% = time to recovery of T 1 to 25% of baseline; T 75% = time to recovery of T 1 to 75% of baseline; Recovery index = the difference between T 75% and T 25%; TOF 0.7 = time necessary for the TOF ratio to return to 0.7. * P < 0.05, same muscle relaxant, different anesthetic, † P < 0.05, same anesthetic, different muscle relaxant.NMB AGENTS & HEMODINAMIC EFFECTS48propofol anesthesia for each of the muscle relaxants. It was found that degree of potentiation (ratio of ED 50 during TIV A/ED 50 during volatile anesthesia) was 1.2 for sevoflurane in both types of relaxants.Using a single-dose technique for rocuronium, Oris et al.13 reported a lower ED 50 during halothane, isoflurane and enflurane anesthesia compared to TIV A using a cumulative dosing technique. Similarly, Lowry et al.14 demonstrated a significant increase in the apparent potency of rocuronium during anesthesia with 1.5 MAC of sevoflurane compared with propofol anesthesia. The study of Xue et al.15 estimated the potency of rocuronium during sevoflurane and thiopental-nitrous oxide anesthesia and found values in broad agreement with our results. Thomas et al.16 investigated the interaction between the cumulative dose requirements of cisatracurium and anesthesia with isoflurane, sevoflurane, desflurane or propofol using closed-loop feedback control. They found that in comparison to propofol, isoflurane, sevoflurane and desflurane reduce the cumulative dose requirements of cisatracurium by 42%, 41% and 60%, respectively to maintain a 90% depression of T 1 of TOF. Kopman et al.17 suggested that drug potency may be more intense under N 2O anesthesia compared with total IV anesthesia (TIV A).Regarding the clinical duration, we found that it was not significantly different with the different anesthetics or muscle relaxants. Lowry et al.14 demonstrated that the time course of action after a bolus dose of rocuronium 0.6 mg/kg that was studied in patients anesthetized with 66% nitrous oxide in oxygen and 1.5 minimum alveolar anesthetic concentration of sevoflurane or isoflurane, or a propofol infusion did not differ significantly among groups. Similarly Wulf et al.11 concluded that following equi-effective dosing of rocuronium (T 1 > 95%), the clinical duration to 25% T 1 recovery during desflurane, isoflurane, sevoflurane and total intravenous anesthesia did not result in significant difference among these groups.Regarding recovery in the present study, T 75%, the recovery index and TOF 0.7 were significantly prolonged by the use of sevoflurane compared with propofol, and were significantly longer with cisatracurium than rocuronium. Reid et al.18 demonstrated that recovery from rocuronium induced neuromuscular block was slowed in the presence of potent volatileDiscussionThis comparative study determined the influence of sevoflurane on the dose response relationship of either rocuronium or cisatracurium compared to a TIV A with propofol as well as hemodynamic effects of both relaxants under the two anesthetics. The neuromuscular blocking effect of rocuronium and cisatracurium were enhanced by sevoflurane. The interaction between sevoflurane and both neuromuscular blocking drugs (NMBD) led to increased intensity of block and prolongation of recovery in comparison to TIV A with propofol.Usually, potentiation of NMBD by volatile anesthetics results predominantly in prolongation of the duration and recovery of neuromuscular block 11. Recovery was prolonged significantly by the volatile anesthetic sevoflurane under the conditions of the present study. The prolongation of the effect of rocuronium or cisatracurium during sevoflurane anesthesia is probably caused by a faster and more complete equilibrium among the end-tidal, blood, and muscle concentrations of sevoflurane because of its smaller muscle-gas partition coefficient, resulting in slower recovery, as seen in all groups under sevoflurane anesthesia 12. As regarding the potency (augmentation of depression of T 1), we determined the anesthesia-related effects of cisatracurium or rocuronium but not the absolute potency data.The cumulative dose technique may underestimate the p otency o f n euromuscular b locking a gents. H owever, administration of both, cisatracurium and rocuronium was standardized and the use sevoflurane or TIV A with propofol was randomized; thus the cumulative pattern of cisatracurium and rocuronium administration would have similar effects in all groups.In the present study values of ED 50 and ED 95 in the sevoflurane Groups were significantly lower than those in the propofol Groups for each muscle relaxant. The values of mean ED 50 and ED 95 of rocuronium were lower during sevoflurane anesthesia than with TIV A. Similarly the values of mean ED 50 and ED 95 of cisatracurium were lower during sevoflurane anesthesia than with TIV A. However, the slope of the curve and the ED 95/ED 50 ratio were comparable among the Groups. The cumulative dose-response curve was shifted to the left with sevoflurane anesthesia as compared toA. M. AMIN ET. AL。
1_例复发性胸腺瘤患者信迪利单抗治疗过程中出现心肌损伤的原因及处理
1例复发性胸腺瘤患者信迪利单抗治疗过程中出现心肌损伤的原因及处理李泞甫1，2，李智可1，2，陈旭澜1，2，皈燕21 川北医学院临床医学系，四川南充637000；2 川北医学院附属医院肿瘤科摘要：目的 总结复发性胸腺瘤患者信迪利单抗治疗过程中出现心肌损伤的原因，探讨有效处理方法。
方法 对1例复发性胸腺瘤信迪利单抗治疗过程中出现心肌损伤的患者临床资料作回顾性分析。
结果 患者2年前因胸腺瘤接受手术切除（R2切除） + 术后放射治疗，2年后出现复发伴肺转移，4周期CAP方案（环磷酰胺890 mg + 盐酸表柔比星130 mg + 顺铂80 mg）化疗后疾病进展。
与患者家属沟通后，予以信迪利单抗200 mg静脉注射（每三周一次）联合CAP化疗。
联合治疗1周期后，出现心肌酶谱升高、完全性右束支传导阻滞、眼睑下垂等心肌损伤症状，考虑为免疫性心肌炎。
使用甲强龙500 mg冲击治疗及其他对症支持治疗后，症状无明显好转，加用抗心律失常药物（胺碘酮、艾司洛尔）、吗替麦考酚酯及免疫球蛋白，但患者病情恶化于次日凌晨2时突发呼吸心脏骤停，抢救无效死亡。
结论 复发性胸腺瘤患者应用信迪利单抗治疗过程中可能发生心肌损伤，发生原因可能与胸腺为免疫器官及免疫治疗联合化疗的不良反应有关。
对于使用免疫治疗联合化疗的胸腺瘤患者应高度警惕，需动态监测心肌损伤指标，早期识别，分级治疗。
关键词：心肌损伤；心肌炎；免疫性心肌炎；药物不良反应；免疫检查点抑制剂doi：10.3969/j.issn.1002-266X.2023.33.018中图分类号：R730.51 文献标志码：A 文章编号：1002-266X（2023）33-0076-04恶性肿瘤和心血管疾病是全球范围内导致死亡的两大主要原因［1］。
免疫治疗、蒽环类药物及靶向药的应用明显改善患者预后，但其心血管不良反应已经成为影响肿瘤患者生存和预后的重要因素。
蒽环类药物引起心肌损伤的机制主要为加重氧化应激、干扰铁代谢，而免疫治疗主要是是通过激活全身免疫反应，抑制肿瘤细胞免疫逃逸［2-3］。
矿物质缺乏引发的疾病
Pedosphere24(1):13–38,2014ISSN1002-0160/CN32-1315/Pc 2014Soil Science Society of China Published by Elsevier B.V.and SciencePressSources and Deficiency Diseases of Mineral Nutrients inHuman Health and Nutrition:A ReviewU.C.GUPTA1,∗1and S.C.GUPTA21Agriculture and Agri-Canada Canada,Crops and Livestock Research Centre,Charlottetown,PE C1A4N6(Canada)2The Department of Plastic Surgery,Loma Linda University,Loma Linda,CA92354(USA)(Received August30,2013;revised December8,2013)ABSTRACTMineral nutrients are fundamentally metals and other inorganic compounds.The life cycle of these mineral nutrients begins in soil,their primary source.Soil provides minerals to plants and through the plants the minerals go to animals and humans;animal products are also the source of mineral nutrients for humans.Plant foods contain almost all of the mineral nutrients established as essential for human nutrition.They provide much of our skeletal structure,e.g.,bones and teeth.They are critical to countless body processes by serving as essential co-factors for a number of enzymes.Humans can not utilize most foods without critical minerals and enzymes responsible for digestion and absorption.Though mineral nutrients are essential nutrients,the body requires them in small,precise amounts.We require them in the form found in crops and they can be classified into three different categories:major, secondary,and micro or trace minerals.This classification is based upon their requirement rather than on their relative importance. Major minerals such as potassium(K)and phosphorus(P)are required in amounts of up to10g d−1.The daily requirement of secondary and micro minerals ranges from400to1500mg d−1and45μg d−1to11mg d−1,respectively.To protect humans from mineral nutrient deficiencies,the key is to consume a variety of foods in modest quantities,such as different whole grains,low fat dairy,and different meats,vegetables and fruits.For insurance purposes,a supplement containing various mineral nutrients can be taken daily.Key Words:deficiency diseases,deficiency symptoms,origin,recommended daily dose,toxicityCitation:Gupta,U.C.and Gupta,S.C.2014.Sources and deficiency diseases of mineral nutrients in human health and nutrition: A review.Pedosphere.24(1):13–38.INTRODUCTIONLike water,carbohydrates,proteins,fats,vitamins and the enzymes required to digest them,mineral nu-trients are also essential to life.Minerals are inorganic substances,present in all body tissues andfluids and their presence is necessary for the maintenance of cer-tain physicochemical processes which are essential to life(Soetan et al.,2010).Over99%of the adult body’s 1000–1200g calcium(Ca)is in the bones and teeth, yet the remainder,less than1%,plays an essential part in the functioning of many diverse vital activities,such as maintenance and functioning of cell membranes and activation of enzymes and hormone secretion(Wise-man,2002).Humans require a number of mineral nu-trients known to play key role in maintaining human health.This investigation will include mineral nutri-ents which have been shown to be essential and of ut-most importance to human health.Silica(Si),tin(Sn) and cobalt(Co)are excluded from discussion as these are in plentiful supply in nature and their deficiency is seldom encountered.Furthermore,the understanding of their roles is less exact.Carbon(C),oxygen(O)and hydrogen(H)are primarily derived from air and water and are not discussed;nitrogen(N),a major mineral, has also been excluded as it is a component of proteins and that is not a part of the objective of this study.Mineral nutrients are the key to the engines we know of as vitamins.No vitamin can be absorbed or can carry out its intended function without the spe-cific minerals in very particular amounts.Minerals are fundamentally metals and other inorganic compounds that provide much of our skeletal structure,e.g.,bones and teeth.In addition,they are critical to countless body processes(Wikipedia Foundation Inc.,2002).Mineral nutrients can be separated into major,se-condary and micro or trace minerals.This classifica-tion is based on their requirement by humans rather than their relative importance.The mineral nutrients included in this study are categorized as follows.Ma-jor:P and K;secondary:calcium(Ca),magnesium (Mg)and sulfur(S);and micro,trace or rare:boron∗1Corresponding author.E-mail:umesh.gupta@agr.gc.ca.14U.C.GUPTA AND S.C.GUPTA(B),chlorine(Cl),chromium(Cr),fluoride(Fl),iodine (I),iron(Fe),manganese(Mn),molybdenum(Mo), nickel(Ni),selenium(Se),sodium(Na),vanadium(V) and zinc(Zn).With ongoing and future research,this list is expected to grow longer.The objective of this review was to report up-to-date information on mineral nutrients,their origin and natural occurrence,sources,daily requirement,func-tions,symptoms associated with their deficiency dis-eases,and their role in human nutrition.NATURAL OCCURRENCE OF MINERALSPlant foods contain almost the entire nutrient mi-nerals and organic nutrients established as essential for human nutrition.Every form of living matter re-quires these inorganic elements or mineral nutrients for their normal life processes(Soetan,2010).Mine-rals are inorganic(non-carbon)containing nutrients and are either positively charged(cation)or nega-tively charged(anion).Mineral nutrients are elements remaining after foods are burned completely to ash (Greene,2000).The primary and the only source of mi-neral nutrients found in plants,animals and humans is soil.The kinds of nutrients found vary depending upon the origin of the soil.For example,B occurs in high concentrations in sedimentary rocks and in clay-rich marine sediment due to the relatively high concentra-tion of B in seawater(Samir et al.,2011).Deposits of B are found in association with volcanic activity and where marshes or lakes have evaporated under arid conditions(Samir et al.,2011).The abundance and diversity of nutrient minerals are controlled directly by their chemistry,in turn de-pendent upon elemental abundance in the earth.The majority of minerals are derived from the earth’s crust (Stipanuk and Caudill,2012).Eight elements in order of decreasing abundance are:O,Si,aluminum(Al),Fe, Mg,Ca,Na and K,which comprise98%of the earth’s crust by weight(Stipanuk and Caudill,2012).Inor-ganic minerals include matter other than plant or ani-mal and do not include C,H and O as in living things.RELATIONSHIP OF MINERAL NUTRIENTS TO HUMAN NUTRITIONMineral nutrients are absolutely essential for good health.Scientists have established that at least28mi-neral elements are indispensable for normal nutrition (Health Lifestyles Inc.,1993).Furthermore,they are even more important than cking vitamins, the body can make some use of minerals,but lacking minerals,vitamins are useless(Health Lifestyles Inc., 1993).The shocking fact is that even if one prides themselves on eating a well-balanced diet,they are probably among the95%of Americans who are lac-king in at least one major mineral nutrient.The root of this problem lies in a mineral-poor earth.As far back as1936,Senate Document No.264warned Ame-ricans that the soils used to grow fruits and vegetables were seriously deficient in needed minerals.Continu-ous cropping and the ravages of pollution were even then robbing the soil of the minerals needed to sustain life(Health Lifestyles Inc.,1993).Unlike the body’s complex organic compounds (carbohydrates,lipids,proteins,vitamins)that are used metabolically in the generation of energy,mine-rals are often found in the form of salts in the body that are inorganic and not metabolized(Carpenter et al.,2013).Minerals constitute about4to6percent of body weight—about one-half as Ca,one-quarter P as phosphates,and the remainder being made up of the other essential minerals that must be derived from the diet(Carpenter et al.,2013).Minerals not only impart hardness to bones and teeth but also function broadly in metabolism,e.g.,as electrolytes in controlling the movement of water in and out of cells,as components of enzyme systems,and as the constituents of many organic molecules(Carpenter et al.,2013).Mineral nutrition in humans is defined as the pro-cess by which substances in foods are transformed into body tissues and provide energy for the full range of physical and mental activities that make up human life(Carpenter et al.,2013).The ultimate goal of nu-tritional science is to promote optimal health and re-duce the risk of chronic diseases,such as cardiovascular disease and cancer,as well as to prevent classic nu-tritional deficiency diseases,such as kwashiorkor and pellagra(Carpenter et al.,2013)MAJOR CROP AND ANIMAL SOURCES AND THEIR RECOMMENDED DAILY DOSESRecommended daily doses of all mineral nutrients stu-diedAll foods contain several mineral nutrients;ho-wever,some are higher in certain minerals than other minerals.The recommended doses vary considerably as established by various agencies related to regulation of mineral nutrients in various foods.A dietary requirement is defined as the lowest con-tinuing intake of a nutrient that,for a specified indica-tor of adequacy,will maintain a defined level of nutri-ture in an individual(Sutherland et al.,1998).An es-sential dietary component is one that the body can not synthesize in sufficient quantities to maintain health.SOURCES AND DEFICIENCY DISEASES OF MINEARL NUTRIENTS15Recommended dietary allowances are based on esti-mates of the dietary requirements,and are designed to prevent deficiency diseases and promote health through an adequate diet(Lenntech,1998).In1996, the Food and Nutrition Board(FNB)began a revi-sion process of the recommended dietary allowances using as criteria specific indicators of adequacy and functional end points for reducing the risk of chronic diseases.Boron is a dietary component,and evidence from animal studies indicates that it is a dietary essential; it can not be synthesized in tissues,and organisms ex-posed to very low levels of B show developmental de-fects(Lenntech,1998).Recommended daily dosages of various mineral nutrients are reported in Table I.It is evident that their amounts vary considerably.BoronThe average B concentration in the earth’s crust is17mg kg−1and most soils fall within the range of 3–100mg kg−1(Samir et al.,2011).In general,these amounts in soils are lower than most essential micronu-trients with the exception of Mo and Se.Deficiency of B has been found to affect the physi-ology of human beings(Shaaban,2010).Boron may be beneficial for bone growth and maintenance,cen-tral nervous system function,and the inflammatory response(Nielsen,2009).The best documented benefi-cial effect of B is on Ca metabolism and utilization,and thus affects bone calcification and maintenance (Nielsen,1998a).The highest B concentration is found in bones,indicating one of the potential benefits in its ability to protect humans from osteoporosis(Nielsen, 1998).It has been reported that B appears to lessen effects of a low Mg-diet on body growth,serum choles-terol and ash concentration in bone,but exacerbate deficiency symptoms,without affecting the Mg or Ca concentration in the serum(Kenny and McCoy,2000).The elevation of endogenous steroid hormones as a result of B supplementation suggests that B may be used as an ergogenic,safe substance for athletes,but needs further investigation(Naghii,1999).Boron sup-plementation also has been found to result in high B absorption efficiency and the elevation of endogenous estrogen suggests a protective role of B in atheroscle-rosis(Naghii and Samman,1997).In humans,there is evidence of homeostatic regulation of B;e.g.,human milk B concentrations are under apparent homeostatic control(Hunt,2007).Boron satisfies the criterion of essentiality and tissue B concentrations during short term variations in intake are maintained by homeo-static mechanisms(Hunt,2007).In most studies it has been found that B affects human steroid hormone levels.Circulating testoste-rones and estradiol levels have been proposed to mo-dify prostate and cancer risk(Wiseman,2002).After controlling for age,race,smoking,body mass index, dietary caloric intake,and alcohol consumption,incre-TABLE IRecommended daily dosages a)of mineral nutrientsMineral nutrient Lenntech(1998)Wikipedia—The Free Balch and Balch(2000)Encyclopedia(2012)Boron(mg)20-3–6Calcium(mg)10001000–13001500–2000(as citrate or ascorbate) Chlorine(mg)3400(in chloride form)2300–3400-Chromium(μg)12035–120150–400(as glucose tolerance factor orpicolinate or polynicotinate)Copper(mg)20.9–22–3Fluoride(mg) 3.54-Iodine(mg)0.150.15100–225Iron(mg)151818–30Magnesium(mg)350400–420750–1000Manganese(mg)52–2.33–10Molybdenum(μg)7545–7530–100(as ascorbate or aspartate) Nickel(mg)<1--Phosphorus(mg)10001000-Potassium(mg)3500350099–500(as citrate)Selenium(μg)3570100–200Sodium(mg)24002400-Sulfur(mg)---Vanadium(mg)<1.8 1.80.2–1(as vanadyl sulfate)Zinc(mg)1511–1530–50a)A range of values from recommended daily intake to maximum recommended daily allowance of daily reference intakes.16U.C.GUPTA AND S.C.GUPTAased dietary B intake was generally associated with a decreased risk of prostate cancer with a dose-response pattern(Cui et al.,2004).When with the high B in-take,low dietary B resulted in significantly poorer performance on tasks emphasizing manual dexterity, eye-hand coordination,attention,perception,encoding and short-term memory,and long-term memory.Col-lectively,the data from these studies indicate that B may play a role in human brain function and cognitive performance,and provide additional evidence that B is an essential nutrient for humans(Penland,1994).One of the reasons why many researchers think B helps treat arthritis is that it is essential for the strengthening of bones.Boron helps metabolize many bone strengthening minerals like Ca,Cu and Mg(Sti-panuk and Caudill,2012).There is also evidence that B provides several health benefits to the brain.It is widely believed that B can positively influence a di-verse set of brain functions including memory,concen-tration,and even hand-eye coordination(Stipanuk and Caudill,2012).Data on dietary B intake by human beings are fairly sparse.Boron is not included in the United States Department of Agriculture nutrient databases,and no comprehensive analytical database exists on the B con-tent of specific foods.In an American study,the B levels were slightly higher in vegetarian adults than in the general population(Rainey et al.,1999).It was stated that the top two B contributors,coffee and milk, are low in B,yet they make up12%of the total B in-take by virtue of the volume consumed.Peanut butter, wine,raisins,apples,pears,grapes,avocados,legumes, peanuts and other nuts are good sources of B(Rainey et al.,1999;Stipanuk and Caudill,2012).Diets low in fruits,vegetables,legumes and nuts may not provide an adequate amount of B.CalciumCalcium is thefifth most abundant element by mass in the earth’s crust.It is everywhere on the planet,and this common mineral provides a number of health benefits to the human body(Stipanuk and Caudill,2012).Most well-known health benefit of Ca is the important part it plays in developing strong bones. Almost all the body’s Ca can be found in the bones and teeth,and there are countless studies which show that proper Ca intake helps young people develop strong bones while keeping the bones of older people strong and healthy.It also helps to prevent and treat a vari-ety of bone-related illnesses,such as osteoporosis(Sti-panuk and Caudill,2012).In addition to fulfilling the needs for Ca ions re-quired in numerous intracellular functions as well as for the regulation of blood clotting(hemostasis),prac-tically all of the body’s remaining Ca exists in skele-tal salts that support the body,enable ambulation, and protect internal organs.Afixed amount of Ca forms the teeth which,after formation,remains static in the oral cavity and which,unlike the bones,do not participate in Ca metabolism(Anderson and Garner, 2011).Following the achievement of peak bone mass in the second or third decade of life,dietary Ca is needed to replace Ca lost from bone tissue as part of the normal dynamic turnover of the skeleton.Adult bone mineral content and bone mineral density are better maintained by an adequate amount of Ca in the diet(Anderson and Garner,2011).Dietary supplement use is associated with a higher prevalence of groups meeting the adequate intake for Ca and vitamin D.Monitoring usual total nutrient in-take is necessary to adequately characterize and evalu-ate the population’s nutritional status and adherence to recommendations for nutrient intake(Bailey et al., 2010).Knowledge of osteoporosis and the importance of dietary intake of Ca and vitamin D did improve after the intervention(Bohaty et al.,2008).Osteoporosis is a painful,disabling illness and its prevention is a lifelong process.Older women may suffer its devastating effects because of these nutrient deficiencies in their diet as young adult women(Bohaty et al.,2008).Epidemio-logical and prospective studies have related vitamin D deficiency not only to osteoporosis but also to cardio-vascular disease,diabetes,cancer,infection and neu-rodegenerative disease(P´e rez-L´o pez et al.,2012).In a study in Japan,an excessive intake of400mg Ca-fortifiedfish sausage,a special health food in Japan, appeared to be a safe means to obtain the daily Ca requirement(Murota et al.,2010).Inadequate sunlight exposure and Ca intake during rapid growth at puberty lead to hypocalcemia,hypovi-taminosis D and eventually to overt rickets(Dahifar et al.,2007).It was concluded that low daily Ca intake and vitamin D acquirement are two important prob-lems in Iranian girls during rapid growth at puberty; therefore,for prevention of overt rickets,Ca and vita-min D supplementation appears to be necessary(Dahi-far et al.,2007).In a study involving the mean daily Ca intake at553mg d−1,along with other minerals in pregnant women,it was found that only Ca intakes were significantly correlated to birth weight(Denguezli et al.,2007).In a US study,milk and milk products were by far the lowest-cost sources of dietary Ca and also were among the lowest-cost sources of riboflavin and vita-SOURCES AND DEFICIENCY DISEASES OF MINEARL NUTRIENTS17min B12(Drewnowski,2011).An intake of approxi-mately1500mg Ca d−1could aid in the management of body and truncal fat.It has been recommended that young adults be encouraged to increase their total Ca intakes to at least the recommended daily allowance of 1000mg d−1for reasons extending beyond bone health (Skinner et al.,2011).The tolerable upper Ca intake level ranges from1000to3000mg d−1,based on Ca excretion or kidney stone formation,and vitamin D from1000to4000international units daily,based on hypercalcemia adjusted for uncertainty resulting from emerging risk relationships(Ross et al.,2011).Due to the nutrient synergy of foods,dietary Ca sources should continue to be promoted in nutritional counselling efforts as the optimal method of obtaining adequate Ca(French et al.,2008).Nutrition education should emphasize strategies to decrease the side effects associated with Ca-rich foods and alleviate concerns re-garding the cholesterol and fat content of some Ca-rich foods.In addition to strategies to increase consump-tion of dietary Ca sources,supplementation should be considered as an acceptable method of increasing Ca intake among women with low bone mineral den-sity(French et al.,2008).In a study in USA,African Americans in all age groups did not meet dairy re-commendations from the2005US Dietary Guidelines and the2004National Medical Association(Fulgoni III et al.,2007).Calcium and Zn intakes in Australian children from core foods were below70%of the recommended dietary intakes for adolescent girls(Rangan et al.,2008).It was concluded that the extra foods are over-consumed at two to four times the recommended limits and con-tribute excessively to the energy,fat and sugar intakes of Australian children,while providing relatively few micronutrients,including Ca(Rangan et al.,2008).Milk,cheese and most other dairy products,beans (Phaseolus vulgaris),broccoli(Brassica olereracea var. italica)kale(Brassica oleracea var.acephala),collards (Brassica oleracea hardiness)and raisins are some of the best sources of Ca(Stipanuk and Caudill,2012).ChlorideDrinking water disinfection has been shown to be an important public health measure since the turn of the century.In USA,it was perhaps the single most important factor in controlling typhoid fever,a water-borne disease that was rampant throughout the world during the last century(Akin et al.,1982).Disinfec-tion was important in limiting diseases,such as cholera, amoebiasis,salmonellosis,and hepatitis A(Akin et al., 1982).Still,despite its beneficial effects and lifesaving reputation,other chlorine effects on health and envi-ronment are dangerous to humans(Conjecture Corpo-ration,2003).Chlorine is essential for bodyfluid regulations in humans(Evans and Solberg,1998)and exists in the safe,inorganic form as the negative chloride ion as NaCl(Belkraft,2005).But when Cl reacts with organic compounds in the water,it produces poisonous che-mical compounds,which cause cancer and other health problems(Belkraft,2005).Following inhalation and skin or eye contact,exposure to HCl acid is toxic by ingestion and skin or eye exposure(Bul,2011).It has been hypothesized that organochlorine pesticides may be associated with the increased incidence of breast cancer in women and decreased sperm concentrations and reproductive problems in men(Safe,1995).Ho-wever,elevation of some organochlorine compounds in breast cancer patients is not consistently observed (Safe,1995).Methyl chloride is very toxic;mice ex-posed to high levels of methyl chloride by inhalation for two years had an elevated incidence of liver and lung tumors(Green,1997).The mouse seems to be unique in its response to methyl chloride and thus it is an inappropriate model to assess human health(Green, 1997).The data from Bangladesh showed that the ma-rine salt deposition is significant up to a distance of about200m from the seashore and from this point onward,the amount of chlorides drops sharply(Hos-sain and Said,2011).Chloride exists in aqueous solu-tions as a monovalent anion and its salts are readily soluble.Consequently,it is not absorbed by organic matter or clay in most soils,and does not readily pre-cipitate out of solution(Hossain and Said,2011).For these reasons,Cl is mobile in the soil and is readily leached where rainfall and/or irrigation exceeds evapo-transpiration.Chloride is one of thefirst elements re-moved from minerals by soil weathering processes.This is why most of the world’s Cl is found in oceans or in salt deposits left by evaporation from old inland seas (International Plant Nutrition Institute,2012).Many soils and crops receive more than an adequate supply of Cl from sea spray carried by rain and snow.This diminishes rapidly with the distance from the ocean (International Plant Nutrition Institute,2012).Results from disinfecting student health centres (SHCs)in Taiwan suggested that the air quality guide-lines prescribed by the Taiwan Environmental Protec-tion Agency for SHCs and other healthcare facilities can best be achieved by applying chlorine dioxide at regular(daily)intervals(Hsu et al.,2012).The results from southern Italy on ground water provided valuable18U.C.GUPTA AND S.C.GUPTAinactivation constants of cultural indicators,e.g.,co-liforms,enterococci,Clostridium spores and viruses in the wastewater that have been injected into the fra-ctured aquifer since1991(Masciopinto et al.,2007). Hypochlorination reduces somatic coliphages and Clo-stridium spores in groundwater but did not achieve complete inactivation in all tests.It was concluded that complete disinfection of groundwater samples was pos-sible only when there was an initial count of Clostrid-ium spores of≤10colony-forming units100mL−1 (Masciopinto et al.,2007).It has been reported that naturally occurring indicator bacteria and bacterio-phages respond differently to chlorination in drin-king water distribution networks in northeastern Spain (Mendez et al.,2004).Though several chlorinated organic compounds are produced by humans,some are also produced by the biotic and abiotic processes in the environment(My-neni,2002).These carcinogenic and toxic compounds are formed at rapid rates from the transformation of in-organic Cl during humification of plant material,thus playing a critical role in Cl cycling,and from the trans-formation of several major and trace elements in the environment and may influence human health(My-neni,2002).Chlorinated drinking water is one of the chief source of Cl.Disinfection with chlorine is one of the safest way of limiting the number of diseases known to be capable of waterborne transmission,e.g.,cholera, amoebiasis,salmonellosis and hepatitis A(Akin et al., 1982).ChromiumChromium is an essential trace mineral that hu-mans require in trace amounts.In1959,Cr wasfirst identified as an element that enables the hormone in-sulin to function properly(Wong,2012).Since then, Cr has been studied for diabetes and has become a po-pular dietary supplement(Wong,2012).Chromium is essential for maintaining health and has many uses and applications in the human body.For instance,there is a great deal of research that suggests that Cr is beneficial to those with impaired glucose tolerance(Stipanuk and Caudill,2012).Impaired glucose tolerance,which is a precursor to type2diabetes for about25%of those who acquire it,is a state in between the glucose levels of dia-betes and normal glucose levels.A meta-analysis on the relationship between Cr and impaired glucose tolerance found that12of the15studies showed a positive effect (Stipanuk and Caudill,2012).The pooled data from the studies using chromium picolinate(CrPic)supple-mentation for type2diabetes mellitus subjects showed substantial reductions in hyperglycemia and hyperin-sulinemia,which equate to a reduced risk for disease complications(Broadhurst and Domenico,2006).Col-lectively,the data support the safety and therapeutic value of CrPic for the management of cholesterolemia and hyperglycemia in subjects with diabetes(Broad-hurst and Domenico,2006).Tissue Cr levels of subjects with diabetes are lower than those of normal control subjects,and a correla-tion exists between low circulating Cr levels and the incidence of type2diabetes(Hummel and Schnell, 2009).However,supplementation with Cr has been shown to reduce insulin resistance and to help reduce the risk of cardiovascular disease and type2diabetes (Hummel and Schnell,2009).The effect of Cr treat-ment on glycemic control in a Western population of insulin-dependent patients with type2diabetes using high-dose Cr treatment showed no evidence that it was effective in obese patients with type2diabetes (Kleefstra et al.,2006).There is evidence of hormonal effects of supplemental Cr besides the effect on in-sulin.Chromium supplementation does result in tis-sue retention,especially in the kidneys,although no pathogenic effect has been demonstrated despite con-siderable study(Lamson and Plaza,2002).In two cases,one involving a diabetic patient and the other a non-diabetic patient,Cr administration appeared to decrease insulin requirements.Infusion of chromic chloride appeared to reduce insulin requirements in one diabetic patient and one non-diabetic patient(Phung et al.,2010).Chromium deficiencies result in decreased insulin sensitivity,glucose intolerance and increased risk of diabetes.In a French study,the Cr status decreased with age,suggesting that the elderly may be at a high risk of Cr deficiency(Roussel et al.,2007).Although these subjects had well-balanced diets,their daily Cr intakes did not reach the French recommendations.It is likely that the low Cr intakes were due to the low Cr density of the foods.A negative correlation was found between Cr intakes and insulin,body mass index and leptin(Roussel et al.,2007).Of all the“essential”elements,the role of Cr is un-doubtedly the most controversial.Recently,its status as an essential element,first proposed nearly60year ago,has been challenged;this challenge will probably result in the general consensus on the status changing (Stallings and Vincent,2006).These new researchers were attracted to thefield by the rapidly expanding po-pular attention received by Cr nutritional supplements, which was not being mirrored by scientific advances in understanding how these supplements could work at a。
秸秆与生物炭对棉田碱性土壤NH3挥发与N2O排放的影响
郭儆瑜，金文，刘志涛，等.秸秆与生物炭对棉田碱性土壤NH 3挥发与N 2O 排放的影响[J].农业环境科学学报,2024,43（2）：442-451.GUO J Y,JIN W,LIU Z T,et al.Effects of straw and biochar on NH 3volatilization and N 2O emission from alkaline soils planted with cotton [J].Journal of Agro-Environment Science ,2024,43（2）：442-451.秸秆与生物炭对棉田碱性土壤NH 3挥发与N 2O 排放的影响郭儆瑜，金文，刘志涛，程照瑞，赵文青，孟亚利*（南京农业大学农学院/农业农村部作物生理生态与生产管理重点实验室/江苏省现代作物生产协同创新中心，南京210095）Effects of straw and biochar on NH 3volatilization and N 2O emission from alkaline soils planted with cottonGUO Jingyu,JIN Wen,LIU Zhitao,CHENG Zhaorui,ZHAO Wenqing,MENG Yali *（College of Agriculture,Nanjing Agricultural University/Key Laboratory of Crop Ecophysiology and Management,Ministry of Agriculture and Rural Affairs/Jiangsu Collaborative Innovation Center for Modern Crop Production （JCIC-MCP ）,Nanjing 210095,China ）Abstract ：The main objectives of this study were to investigate how straw and straw biochar influence soil ammonia （NH 3）volatilization and nitrous oxide （N 2O ）emission after continuous addition for 5years,and to ascertain a practical straw return practice for reducing N loss in alkaline cotton fields.On the basis of the equivalent carbon input,we established four treatments （straw incorporation,straw decomposition plus mulching,straw biochar incorporation,and a control treatment without straw or biochar ）,all of which involved application of the same amount of NPK fertilizers.The results revealed that compared with the control,straw biochar incorporation promoted a significant reduction in NH 3volatilization by 27.3%and N 2O emission by 56.7%.These effects were mainly attributed to the significant inhibition of soil hydroxylamine reductase and nitrate reductase activities,and an increase in N uptake by cotton,as well as thestrong adsorption capacity of biochar per se.Furthermore,compared with the control treatment,straw incorporation and straw decomposition plus mulching increased NH 3volatilization by 37.2%and 21.2%,respectively,but reduced N 2O emissions by 17.1%and38.3%,respectively.These contrasting effects can be ascribed to the fact that that these two straw returning practices promote a significant enhancement of soil organic N mineralization and hydroxylamine reductase activity,while inhibiting nitrate reductase activity.Redundancy收稿日期：2023-03-20录用日期：2023-06-07作者简介：郭儆瑜（1998—），女，河南郑州人，硕士研究生，从事有机物料对农田氮循环影响研究。
ENHANCEMENT OF CELLULAR GALLIUM UPTAKE
专利名称：ENHANCEMENT OF ELLULAR GALLIUM UPT AKE
发明人：MORTON, KATHRYN, A.,ROULLET, JEANBAP T IST E
申请号：EP99917399 申请日：199904 08 公开号：EP1069918A4 公开日：20020220
申请人：OREGON HEALTH SCIENCES UNIVERSITY
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摘要：A method for improving cellular gallium uptake (particularly of tumor cells) by exposing cells to a nifedipine photodegradation product, or an analog thereof. In particular embodiments, the gallium uptake enhancer is selected from the group of A-B and formula (I), wherein A is a pyridine and B is a nitrosophenyl, and n = 1-10. In yet other embodiments, the uptake enhancer is formula (II), wherein R1-9 are independently selected from the group consisting of H, halogen, haloalkyl, NO2, NO, SO2, a C1-6 alkyl, a COOR10 wherein R10 is H or C1-6 alkyl, and an -OR11 wherein R11 is H or C1-6 alkyl; wherein at least one of R5 and R7 is NO. The uptake enhancers are particularly useful in imaging tumors, using such techniques as gallium scanning, in which the dose of the gallium isotope can be decreased or its imaging efficiency improved. Alternatively, the method can be used to improve efficacy of gallium containing chemotherapeutic regimens in the treatment of tumors and hypercalcemia, or to improve the uptake of other chemotherapeutics that use a similar transferrin independent uptake mechanism.
施肥的方法 英语作文
施肥的方法英语作文Title: Methods of Fertilizing。
Fertilizing plays a crucial role in agricultural practices, aiding in the enhancement of soil fertility and ensuring optimal plant growth. There are various methods of fertilizing employed by farmers worldwide, each tailored to specific crops, soil types, and environmental conditions.In this essay, we will explore several common methods of fertilizing and their respective advantages and disadvantages.1. Broadcasting: Broadcasting involves spreading fertilizers uniformly over the soil surface using equipment such as spreaders. This method is commonly used in large-scale agriculture and is relatively cost-effective. However, it may result in uneven distribution, leading to wastageand potential nutrient runoff.2. Band Application: In band application, fertilizersare placed in bands or rows near the plant roots. This method allows for more targeted nutrient delivery, reducing waste and minimizing environmental impact. It isparticularly suitable for row crops such as corn and soybeans.3. Foliar Feeding: Foliar feeding involves spraying nutrient solutions directly onto the leaves of plants. This method enables rapid nutrient uptake through the stomata, bypassing the soil altogether. Foliar feeding is advantageous in situations where soil conditions are unfavorable for nutrient absorption or when immediate correction of nutrient deficiencies is required. However,it is less effective for providing long-term soil fertility.4. Drip Irrigation: Drip irrigation systems deliver water and nutrients directly to the plant root zone through a network of tubes and emitters. Fertilizers are often injected into the irrigation water, ensuring precisenutrient application and minimal wastage. Drip irrigationis particularly beneficial in arid regions with limited water availability, as it promotes water and nutrientefficiency.5. Incorporation: Incorporation involves mixing fertilizers into the soil either before planting or during cultivation. This method ensures better nutrient contact with the root zone and reduces nutrient loss through volatilization or leaching. However, it requires specialized equipment and may increase soil disturbance.6. Organic Fertilizers: Organic fertilizers, such as compost, manure, and plant residues, are derived from natural sources and contain a variety of nutrients essential for plant growth. These fertilizers improve soil structure, enhance microbial activity, and promote long-term soil health. However, organic fertilizers release nutrients slowly and may not provide immediate nutrient availability compared to synthetic fertilizers.7. Slow-Release Fertilizers: Slow-release fertilizers deliver nutrients to plants gradually over an extended period, reducing the frequency of application and minimizing nutrient leaching. These fertilizers are oftenencapsulated or coated to control nutrient release rates. While more expensive than conventional fertilizers, slow-release formulations offer long-lasting nutrient supply and can improve nutrient use efficiency.In conclusion, the choice of fertilizing method depends on various factors, including crop type, soil conditions, and resource availability. By selecting the appropriate fertilization technique and integrating sustainable practices, farmers can optimize nutrient management, improve crop yields, and minimize environmental impact in agricultural systems.。
enhancement造句
以下是30 个关于enhancement 的例句及其中文翻译：1. The company is investing in new technology to enhance its products.（该公司正在投资新技术以增强其产品。
）2. The training program aims to enhance employees' skills and knowledge.（培训计划旨在提高员工的技能和知识。
）3. The new software has enhanced the performance of the computer.（新软件提高了计算机的性能。
）4. The renovations were designed to enhance the building's aesthetic appeal.（装修旨在提高建筑物的美学吸引力。
）5. The addition of new features has enhanced the value of the product.（添加新功能提高了产品的价值。
）6. The use of natural materials enhances the beauty of the space.（使用天然材料增强了空间的美感。
）7. The new lighting system enhances safety and visibility in the workplace.（新的照明系统提高了工作场所的安全性和可见性。
）8. The partnership between the two companies will enhance their market position.（两家公司的合作将增强其市场地位。
）9. The implementation of quality control measures enhances customer satisfaction.（实施质量控制措施提高了客户满意度。
增稳强度 英语
增稳强度英语In engineering and construction, ensuring the stability and strength of structures is paramount. Whether it's a towering skyscraper, a sprawling bridge, or a humble residential home, the integrity of these constructions is vital for safety and longevity. In this article, we will delve into the various methods and techniques employed to enhance the stability and strength of structures.Firstly, one of the fundamental aspects of increasing stability and strength is through the selection of suitable materials. Engineers meticulously analyze the properties of different materials such as steel, concrete, wood, and composite materials to determine their appropriateness for specific applications. Factors such as tensile strength, compressive strength, and durability are carefully evaluated to ensure optimal performance under various conditions.Furthermore, the design phase plays a crucial role in enhancing stability and strength. Advanced computer-aided design (CAD) software allows engineers to create highly detailed and precise blueprints of structures. By employing principles of physics and mathematics, engineers can optimize the structural layout to distribute loads evenly and minimize stress concentrations. This meticulous planning ensures that the structure can withstand external forces such as wind, seismic activity, and live loads.In addition to material selection and design optimization, the construction process itself is critical for ensuring stability and strength. Skilled laborers and construction crews follow strict protocols and quality control measures to ensure that each component is assembled correctly. Advanced construction techniques such as precast concrete elements, post-tensioning, and reinforced masonry further enhance the structural integrity of buildings and infrastructure.Moreover, ongoing maintenance and inspection are essential for preserving the stability and strength of structures over time. Regular inspections help identify potential weaknesses or defects that may compromise structural integrity. Prompt repairs andreinforcement measures can then be implemented to address these issues before they escalate into larger problems.Furthermore, advancements in technology have led to the development of innovative solutions for increasing stability and strength. For example, the use of carbon fiber reinforced polymers (CFRP) and other high-performance materials offer enhanced strength-to-weight ratios and corrosion resistance. Additionally, sensor technology and data analytics enable real-time monitoring of structural health, allowing engineers to detect anomalies and mitigate risks proactively.In conclusion, ensuring the stability and strength of structures is a multifaceted process that involves careful consideration of materials, design, construction, maintenance, and technological advancements. By employing a holistic approach and leveraging the latest innovations in engineering and construction, we can create structures that are not only safe and resilient but also sustainable for future generations.。
微生物生长促进剂 英语
微生物生长促进剂英语Microbial Growth PromotersIntroductionMicrobial growth promoters, also known as probiotics, are substances that enhance the growth and development of beneficial microorganisms in various environments. These additives have gained significant attention in recent years due to their potential to improve human and animal health, as well as their environmental benefits. In this article, we will explore the concept of microbial growth promoters and discuss their importance in different fields.Definition and FunctionMicrobial growth promoters can be defined as substances that stimulate the growth and activity of beneficial microorganisms. They are commonly used in agriculture, aquaculture, and animal husbandry to enhance the growth and health of plants and animals by promoting the growth of beneficial bacteria and fungi. Furthermore, they can also be used to mitigate the negative impacts of harmful bacteria and pathogens.In agriculture, microbial growth promoters are utilized to improve soil fertility, plant growth, and crop yield. These additives contain specific strains of bacteria or fungi that have the ability to enhance nutrient availability, solubilize minerals, and promote root development. By colonizing the roots and forming a symbiotic relationship with plants, probiotics can enhance water and nutrient uptake, protect plants from diseases, and improve their overall health and vigor.In animal husbandry, microbial growth promoters are used to enhance the gut microbiota of livestock and poultry. The digestive system of animals is home to a complex microbial community, which plays a crucial role in nutrient digestion and absorption, as well as in immune system development. By adding probiotics to animal feed, it is possible to modulate the gut microflora, improve nutrient utilization, reduce the incidence of diseases, and enhance growth performance.Environmental BenefitsApart from their applications in agriculture and animal husbandry, microbial growth promoters also offer significant environmental benefits. The use of these additives can reduce the reliance on chemical fertilizers and antibiotics, which can have detrimental effects on ecosystems and human health when overused. By promoting the growth of beneficial microorganisms, microbial growth promoters contribute to the restoration of natural microbial communities and the enhancement of ecological balance.Safety and RegulationThe safety and regulation of microbial growth promoters are of paramount importance to ensure their efficacy and minimize potential risks. Regulatory agencies, such as the Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA), have established guidelines and regulations to evaluate and approve the use of these additives. Strict quality control and monitoring systems are in place to ensure the safety and effectiveness of microbial growth promoters.ConclusionMicrobial growth promoters, or probiotics, are substances that stimulate the growth and activity of beneficial microorganisms. These additives have shown promising results in improving soil fertility, plant growth, animal health, and environmental sustainability. By harnessing the power of beneficial bacteria and fungi, microbial growth promoters offer a more sustainable and eco-friendly approach to agriculture and animal husbandry. However, it is essential to adhere to strict regulations and guidelines to ensure their safety and efficacy. As research in this field continues to advance, microbial growth promoters will likely play an increasingly important role in various industries.。
水蒸气强化纤维素模板改性钙基吸附剂固碳性能及强度
2023年6月王久衡等：水蒸气强化纤维素模板改性钙基吸附剂固碳性能及强度表3列出了C5M10吸附剂在不同蒸汽体积分数下20次循环煅烧后的比表面积和比孔容。
结果表明，蒸汽活化后C5M10颗粒比表面积和比孔容均低于无蒸汽工况，10%蒸汽活化的吸附剂比孔容最低，但其比表面积相对30%和60%蒸汽体积分数下所得吸附剂高约18%。
有研究[25, 29]表明，低蒸汽体积分数下煅烧得到的吸附剂的比表面积变化较小，而高蒸汽体积分数条件下颗粒团聚及孔结构塌陷会形成更大的孔。
颗粒中大孔份额增加有利于CO 2在其内部的扩散，但严重烧结同样会导致吸附剂比表面积大幅降低，二者综合效果则表现为煅烧蒸汽活化后吸附剂固碳性能的耐久性难以进一步提升。
表3结果可与图5中CO 2捕获量互相印证：具备较高比表面积的10%蒸汽活化吸附剂的CO 2捕集能力要优于30%和60%体积分数下的蒸汽活化。
此外，需要注意的是，无活化工况所得吸附剂的比表面积最高，但其20次循环后的碳捕获量最低，推测原因可能为其整体孔隙分布尺度略小于蒸汽活图5 蒸汽含量对C5M10循环捕集CO 2影响表2 蒸汽活化C5M10第20次循环CO 2捕获量蒸汽体积分数/%103060C 20/g·g -10.200.320.2450.22提升幅度（与C0M0对比）/%4513277.559.0提升幅度（与未活化C5M10对比）/%6022.510图4 煅烧后C0M0和C5M10吸附剂XRD谱图图6 不同蒸汽含量煅烧下C5M10循环20次后SEM 图··3221化工进展， 2023， 42（6）化后吸附剂（如图7所示），从而在碳酸化过程中更易于被CaCO 3产物层堵塞，阻碍碳酸化反应的持续进行。
2.4 长循环下蒸汽及活化方式影响为考察循环过程中蒸汽注入对吸附剂CO 2捕集能力的长期影响，在10%（体积分数）蒸汽下开展了C5M10吸附剂的50次循环碳捕获试验，结果如图8所示。
克拉维酸发酵工艺的优化罗斌
克拉维酸发酵工艺的优化罗斌*发布时间：2021-08-03T09:01:18.517Z 来源：《中国科技人才》2021年第12期作者：罗斌* 高春霞花远志杨莉邱崇顺[导读] 本文以棒状链霉菌CV7G-1705-008为出发菌对克拉维酸发酵工艺的优化进行研究。
结果证实，玉米淀粉乳替代玉米淀粉既提高了产量又节约了成本。
培养基中添加天冬氨酸、谷氨酸、苏氨酸、赖氨酸的最佳添加浓度分别为0.02%、0.1%、0.05%、0.1%均有利于克拉维酸的合成。
甲硫氨酸对克拉维酸的合成具有强烈抑制作用，磷酸二氢钾、硫酸亚铁的添加对克拉维酸生物合成有显著影响。
在控制培养基初始pH 7.0，培养温度25 ℃，搅拌转速250 r/min，接种量2.0%、摇瓶装液量45 mL/500 mL的情况下，发酵效价可显著提高。
罗斌* 高春霞花远志杨莉邱崇顺内蒙古联邦制药有限公司内蒙古巴彦淖尔市 015000摘要：本文以棒状链霉菌CV7G-1705-008为出发菌对克拉维酸发酵工艺的优化进行研究。
结果证实，玉米淀粉乳替代玉米淀粉既提高了产量又节约了成本。
培养基中添加天冬氨酸、谷氨酸、苏氨酸、赖氨酸的最佳添加浓度分别为0.02%、0.1%、0.05%、0.1%均有利于克拉维酸的合成。
甲硫氨酸对克拉维酸的合成具有强烈抑制作用，磷酸二氢钾、硫酸亚铁的添加对克拉维酸生物合成有显著影响。
在控制培养基初始pH 7.0，培养温度25 ℃，搅拌转速250 r/min，接种量2.0%、摇瓶装液量45 mL/500 mL的情况下，发酵效价可显著提高。
关键词：克拉维酸；培养基；发酵工艺；优化Optimization of Clavulanic acid fermentation processBing Luo，Chunxia Gao，Yuanzhi Hua，Li Yang，Chongshun Qiu（Inner Mongolia United Laboratories Co.，Ltd，Inner Mongolia Bayanur City 015000）Abstract：This article use Streptomyces coryneformis CV7G-1705-008 as the starting bacterica，the optimization of the fermentation process of clavulanic acid was carried out. The result shows that replacing corn starch with corn starch milk can increase production and save cost. The addition of aspartate，glutamic acid，threonine and lysine in the medium is beneficial to the synthesis of CA，the optimum concentration is 0.02%，0.1%，0.05% and 0.1% respectively.Methionine. The addition of potassium dihydrogen phosphate and ferrous sulfate has a significant effect on CA biosynthesis，the best added concentration is 0.5% and 0.1%，respectively.Key words：Clavulanic acid；Medium；Fermentation process；Optimization克拉维酸（Clavulanic acid，CA）是一种高效的β-内酰胺酶抑制剂，由棒状链霉菌（Streptomyces clavuligerus）产生。