论文部分内容阅读
随着工农业生产的发展,人类与各种化学物质接触的机会越来越多,据估计,常用的化学物质有63000种以上。对于人体来说,有的化学物质是医疗上常用的药物;有的是由于大气、水源、食品的污染而被摄入人体的毒物;还有一些是致癌物质。人类所患的90%的癌是由各种化学物质引起的,截至1972年为止的资料表明:被探讨过的5300种化学物质中有1700种具有一定的致癌作用。上述致癌物、药物、毒物被摄入体内之后,常常在肝内(特别是肝细胞微粒体内)有关酶系的作用下被代谢,在化学结构上和生物活性上发生改变,这一过程称为生物转化(Biotransformation)。生物转化包括代谢活化(由原致癌物变成终致癌物;由无毒或低毒性到有毒或高毒性)以及灭活这两种可能性。越来越多的事实表明,外因是条件,内因是根据,外因是通过内因而起作用的。
With the development of industrial and agricultural production, there are more and more opportunities for human beings to contact various chemical substances. It is estimated that there are more than 63,000 kinds of commonly used chemical substances. For the human body, there are chemical substances that are commonly used in medicine; some are poisons that are taken into the body due to pollution from the atmosphere, water, and food; and some are carcinogenic substances. 90% of human cancers are caused by various chemicals. As of 1972, the data show that 1,700 of the 5,300 chemical substances studied have certain carcinogenic effects. After the above-mentioned carcinogens, drugs, and poisons are taken into the body, they are often metabolized in the liver (especially in the body of liver cells) under the action of the relevant enzyme system, and the chemical structure and biological activity are changed. This process is called Biotransformation. Biotransformation includes both the metabolic activation (from the original carcinogen to the final carcinogen; from non-toxic or low toxicity to toxic or highly toxic) and the possibility of inactivation. More and more facts show that external factors are the conditions, internal factors are the basis, and external factors work through the internal factors.