药物(或化学物质)的急性毒性试验——半数致死量(LD50)的测定,可提供人们认识和了解在短期内使用药物(或化学物质)时是否会引起危害机体的信息资料。因此,LD_(?0)常作为特别药物(或化学物质)毒性程度的重要参数,也是评价药物(或化学物质)安全性的一个不可缺少的重要指标。毒理学研究中,在分析毒效的特点、毒性作用方式、计算毒效留存率、衰减率、半衰期、蓄积性毒性以及二种或多种药物(或 The acute toxicity test (LD50) of drugs (or chemicals) can provide people with information and understanding of whether or not the drug (or chemical substance) will cause harm to the body in the short term. Therefore, LD_(?0) is often used as an important parameter for the degree of toxicity of a particular drug (or chemical substance) and is an indispensable and important indicator for evaluating the safety of a drug (or chemical substance). In toxicology studies, the characteristics of toxic effects, the mode of toxic effects, the calculation of the retention of toxic effects, the decay rate, half-life, cumulative toxicity, and two or more drugs (or