科技英语翻译第三篇

Heat shock proteins (HSPs) are a group of proteins that are present in all cells in all life forms. They are induced when a cell undergoes various types of environmental stresses like heat, cold and oxygen deprivation.

Heat shock proteins are also present in cells under perfectly normal conditions. They act like “chaperones”，making sure that the cell’s proteins are in the right shape and in the right place at the right time. For example, HSPs help new or distorted proteins fold into shape, which is essential for their function. They also shuttle proteins from one compartment to another inside the cell, and transport old proteins to “garbage disposals” inside the cell. Heat shock proteins are also believed to play a role in the presentation of pieces of proteins (or peptides) on the cell surface to help the immune system recognize diseased cells.

For decades it has been known that animals can be ‘vaccinated’ against cancer. This is how it works: Tumor cells can be weakened and injected like a vaccine into a mouse. Afterwards, if these same tumor cells, at full strength, are injected into the mouse, the mouse will reject the tumor cells and cancer will not develop. However, if a mouse has not been vaccinated in this manner, t he tumor cells will “take root” and the mouse will develop cancer.

Although it was clear that animals could be vaccinated against cancer, for a long time it was not known how it worked. Then about 25 years ago, a graduate student named Pramod Srivastava began a series of experiments. He took tumor cells, broke them open, and separated the different parts of the cells into fractions. He then used each of the fractions as “vaccines” to see which fraction protected the mice from developing cancer. After many experiments, he found that the element responsible for protecting the mice was heat shock proteins.

热应急蛋白是一组存在于一切生命形式的所有细胞中的蛋白质。细胞处于不同形式的环境压力（如遇热、遇冷或缺氧）下就会诱发这种蛋白质的产生。

在完全正常的条件下，细胞内也会产生热应急蛋白，这些蛋白质就像“陪护” 一样，确保细胞内的蛋白质在合适的时间处于合适的位置并具有合适的形状。例如，它们帮助新生细胞或变形的细胞折叠成形，这对于细胞功能的发挥极其重要。热应急蛋白还将蛋白质从细胞的一个部分转移到另一个部分，或将衰老的蛋白质送入细胞的“垃圾处理厂”。科学家认为它们对于细胞表面蛋白质或多肽的生成也起着作用，从而帮助免疫系统辨认不健康的细胞。

几十年前人们就已经了解到动物可以通过“接种疫苗”抗癌，其原理是：肿瘤细胞可以被弱化并像疫苗一样注射到小鼠体内。此后，如果将相同的、已充分发育的肿瘤细胞注入小鼠, 小鼠就会对这些肿瘤细胞产生排斥，因此不会患上癌症。然而，如果小鼠没有以上述方式接受免疫，肿瘤细胞就会“生根' 导致小鼠患上癌症。

虽然人们已经清楚地了解到动物可以通过免疫抗癌，但在很长一段时间内对于该过程的原理并不了解。大约25年前，一位名叫Pramod Srivastava的研究生做了一系列实验，他取出若干肿瘤细胞，将它们剖开，并将细胞的各部分分割成块。然后他把每一块当作“疫苗”，以观察哪一块保护小鼠不患癌症。经过多次实验，他发现起到保护作用的那一部分正是热应急蛋白。