医学英语课后翻译

UNIT1

1.Although the DNA in the nucleus of each cell contains all of the genetic information for all human traits, only a small number of genes are actually active in a particular cell. These active genes are the codes for the proteins necessary for the

specific cell type.

尽管每一个细胞核中的DNA都包含有人类特性的所有遗传信息，但实际上只有少数基因在特定细胞中有活性，这些活性基因是特有的细胞类型所必需的蛋白密码。

2.In facilitated diffusion, molecules move through a membrane from an area of greater concentration to an area of lesser concentration, but they need some help to do this.

在易化扩散中，分子经一层膜从高浓度区域向低浓度区域移动，但分子要完成这一工作需要某些帮助。

3.The cell membrane is selectively permeable, that is, certain substances are permitted to pass through and others are not.

细胞膜的渗透性是有选择性的，即某些物质允许通过，而其他物质则不行。

4.Filtration means that water and dissolved materials are forced through a membrane from an area of higher pressure to an area of lower pressure. 过滤是指水和已溶解物质经一层膜从高压区到低压区。

5.Active transport requires the energy of ATP to move molecules from an area of lesser concentration to an area of greater concentration. 主动转运需要ATP这种能量，使分子从低浓度区域向高浓度区域移动。

Unit2

1.At either end of the age spectrum, however, temperature regulation may not be as precise as it is in older children or younger adults.

然而，在年龄段两端的人群，其体温调节精确程度都不如少年或青年人。

2.The pathways of heat loss from the body are the skin, respiratory tract, and to a lesser extent, the urinary and digestive tracts.

人体散热途径是经皮肤、呼吸道，少量经尿道和消化道散热。

3.Changes in body temperature also have an effect on metabolic rate and heat production. This becomes clinically important when a person has a fever, an abnormally high body temperature.

人体体温的变化也会影响代谢率和产热。当一个人发热、体温异常升高时，从临床上讲，体温变化就显得重要了。

4.Anabolism means synthesis or “formation” reactions, the bonding together of smaller molecules to form larger ones.

合成代谢是指综合或“形成”性反应，即把小的分子结合在一起形成更大的分子。

5.Catabolism means decomposition, the breaking of bonds of larger molecules to form smaller molecules. Cell respiration is a series of catabolic reactions that break down food molecules to carbon dioxide and water.

分解代谢是指分解，即将较大分子的键打断使其分解成小分子。细胞呼吸过程就是一连串的分解代谢反应——将食物分子分解成二氧化碳和水。

UNIT3

1.Ventricular contraction forces blood against the flaps of the right and left A V valves and closes them; the force of blood also opens the aortic and pulmonary semilunar valves.

心室收缩使血液施压于左右房室瓣并使其关闭；血液的压力也使主动脉半月瓣和肺动脉半月瓣打开。

2.Palpations are usually not serious, and may be the result of too much caffeine, nicotine, or alcohol. Much more serious is ventricular fibrillation, a very rapid and uncoordinated ventricular beat that is totally ineffective for pumping blood.

心悸通常不会很严重，可能因摄入的咖啡因、尼古丁或酒精过量引起。更为严重的是室颤，室颤是一种快速而无节律的心室跳动，可以导致心脏无效泵血。

3.Although the heart generates and maintains its own beat, the rate of contraction can be changed to adapt to different situations. The nervous system can and does bring about necessary changes in heart rate as well as in force of contraction

尽管心脏自身产生心跳并维持心跳，但为了适应不同情况还可以改变收缩率。神经系统能使心率和心肌收缩力进行必要的改变。

4.The heart will also be the effector in a reflex stimulated by a decrease in the oxygen content of the blood. The aortic receptors are strategically located so as to detect such an important change as soon as blood leaves the heart.

心脏在受到血氧量下降激起的反射中起到效应器的作用。主动脉感受器的位置非常关键，因而在血液从心脏泵出时，