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Mendel was accused by Fisher that his observed data, which corresponded to expectations, were too good to be true, and, further, that Mendel, growing only 10 plants per offspring, disregarded in his genotypical analysis the loss of recessives by assuming a ratio of 1:2 instead of 1.1126:1.8874. In contrast, it is proposed here that all chi-square statistics of genetic segregations fall short because the variance of genetic segregations is smaller and not of a binomial type as assumed. Furthermore, this variance and the corresponding chi-square statistics are not homogeneous in different segregation types. Consequently, it is not possible to summarize the different chi-square statistics as Fisher did. It is only in this way that he was able to obtain his unrealistic result (a probability of "seven times in 100,000 cases"). Regarding Fisher's second accusation, it should be taken into account that Mendel selected his 10 plants from offspring with a finite and not an infinite number of entities. Although this number is different from offspring to offspring, the average number is about 30. This means that the loss of recessives must be calculated by using a hypergeometric and not a binomial model as Fisher did. Consequently, the real deviation from the 1:2 ratio can be disregarded.  相似文献   

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In order to obtain a critical review of E.A. Müller's "Leistungspulsindex", we worked out a functional representation of that index, using a simple physiologic-mathematic model of the oxygen transport system. We found that the LPI is influenced by the economy of the oxygen transport system and that it is inversely proportional to stroke volume, caloric coefficient, and to the efficiency of muscular work. Based on the theoretic analysis we tried to interpret the results of an investigation carried out with pupils of an coeducative intermediate school (years of birth 1964, 1965, 1966). We obtained statistically significant correlations (p less than 0.1%) between LPI and parameters characterizing performance capacity (PWC170, heart rate at 100 W work load) and between LPI and body weight. The results of both the theoretic and experimental investigation indicate a dependence of the LPI on factors influenced by physical training processes, but no evidence was found, however, on an interrelationship between LPI and congenital factors of physical performance.  相似文献   

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在常规病理制片技术工作中 ,经常发现淋巴组织 (如淋巴结、鼻咽部组织及扁桃体等 )由于处理不当 ,造成切片染色后组织中间出现发灰现象 ,即镜下核浆染色模糊不清或组织成片不着色。这样将给临床病理诊断带来很大困难。为此 ,我们经大量实验 ,对原组织蜡块再切片后采用下述方法进行处理 ,收到了较好的染色效果。材料和方法1.标本来源 :选取 2 5例 H.E染色切片发灰的淋巴组织原蜡块再进行切片 ,切片厚 5μm。2 .切片的处理方法 :(1)将原蜡块所制切片浸入二甲苯 、 脱蜡各 5 min;(2 )无水酒精 、 浸洗各 2 min;(2 )用无水酒精乙醚等量 (1∶…  相似文献   

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