【摘要】 本文报道一种LD₅₀测定方法的新设计。实验时,不强调寻找100％（Dm）和0％（Dn）估计致死量,而寻找部分致死量（Dp）,以便把实验组安排在LD₅₀的上下。充分有效地利用动物。实验分3轮:探索致死量的范围、粗估和精估LD₅₀。计算时,3轮的有效数据均利用,故称类序贯法。经测定甲基硫酸新斯的明LD₅₀的对比实验证明:新法准确、可靠、经济、省时,似优于常用法。更多还原

【Abstract】 A new design for the experimental method of LD₅₀ estimation is reported. Not emphasizing to look for the 100％ and 0％ estimaled lethal doses（Dm and Dn） in the experimental course, we directed our attention to drug’s partial lethal doses（Dp） in order to arrange the experimental groups around the LD₅₀. Such an arrangement could set a great number of animals to be fully and effectively utilized and the one-third. The whole experimental course is divided animal consumption coutd then he reduced by about into 3 rounds. In the first, for approaching to the dose range of an unknown drug toxicity, 10 animals and 10 concentrations of drug-solution with 3-fo’d dilution will be used. A life-death chain may be given. In the 2nd, for roughly estimating the LD₅₀, 7 groups are arranged in different ways according to the informarion obtained from the chain. The total number of animals used is 19. In the 3rd, for accurately estimating the LD₅₀, 3-4 groups are, in general, arranged around the roughly estimated LD₅₀ obtained from the data of the 2nd round, the total number of animals being about 40. During calculation of the LD₅₀, all available data obtained from the 3 round experiments are utilizcd. So, this new design is called by a term, quasi-sequential method. Finally, the comparative experiments for LD₅₀ estimation of neostigmine methylsulfate were conducted with this design and the common method and. results shew the new method is an accurate, reliab’e, time-saving and economic one and seems to be supperior to the commonly used method.更多还原