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一、人类的正常寿命近年人类的平均寿命普遍延长,许多国家的平均寿命已达70岁以上。正常寿命究竟应该多长?从一些记录中人类寿命最长约为110—150岁。人类预期寿命可以从两个不同的方面来推算。一是从哺乳类动物的成长期计算,即把动物骨骼停止生长作为成长期的终止,动物的寿命约为成长期的5—7倍。人类成长期为20—25岁,人类的寿命约在100—150岁之间。另一是从细胞的体外培养分养的次数来推算,不同种属动物的正常细胞在体外有一定的生命寿期,没有一种细胞在体外能无限期地繁殖下去(Hayflick及Morhead 1961)。分养胚胎成纤维细胞的次数多
First, the normal life of mankind In recent years, the average life expectancy of mankind generally extended, the average life expectancy in many countries has reached 70 years of age. What should be the normal life expectancy? From some records, the longest human life expectancy is about 110-150 years old. Human life expectancy can be calculated from two different perspectives. First, from the growth of mammals calculated that the animal bone growth stopped as a growth stop, the life expectancy of about 5-7 times the growth stage. Human growth is 20-25 years old, human life expectancy is about 100-150 years old. The other is based on the number of cells cultured in vitro to calculate the number of normal animals from different species of animals in vitro have a certain life span, and no cell can be indefinitely propagated in vitro (Hayflick and Morhead 1961). Feeding embryo fibroblasts more often