【摘要】 本文用的8只性成熟雄性猕猴(Macaca mulatta)分成4组,每组二只猴子,分组处理如下:(1)一个个体的二个睾丸分别经二次外科手术阉取,前后手术相隔10天,用作对照材料并验证先阉割一个睾丸对剩留体腔的另一个睾丸的染色体畸变有无影响;(2)左睾阉割10天后,全身照射200仑;(3)左睾阉割10天后,在右睾用6毫米厚的铅室屏蔽的条件下全身照射200仑;(4)在右睾用6毫米厚铅室屏蔽,而左睾直接接受射线的条件下全身照射200仑.照射后第10天取出睾丸,以细胞学方法观察生殖细胞的染色体畸变,并进行变量分析和t测验,将这些数据连同我们过去局部地直接照射睾丸所得的资料一并考察,旨在探讨直接与间接照射的辐射细胞遗传学效应.根据分析结果,可得出如下结论:(1)全身照射与局部照射睾丸对于增高染色体畸变率的效应是相同的,而全身照射时保护睾丸则与对照组没有差别,所以辐射诱发染色体畸变是射线直接作用于染色体的结果,与间接作用是无关的.(2)证明铅室遮盖睾丸对诱发染色体畸变有保护作用.(3)同一个体的二个睾丸先取出一个,对留于体内的另一个睾丸的染色体畸变并无影响.所以一个睾丸作对照,另一个睾丸作处理,或二个睾丸分别作不同处理,这种同体对照的方法是可行的,可以在供试个体不多的情况下既满足实验设计要求又减少了个体差异所可能造成的误差.更多还原

【Abstract】 The investigation reported here was undertaken to obtain informations concerning the relative merits of the direct and indirect exposure of testis to X-irradiation on the chromosome aberrations in the spermatogenesis of the monkey, Macaca mulatta. The materials used consisted of 8 adult male monkeys, which were set into 4 groups with 2 animals each as follows: in the first group, the 2 testes of same animal were taken out at two separate operations with 10 days apart. They were intended to serve as controls as well as to find out whether precastration of one testis would affect the frequency of chromosome aberrations in the retained testis. In the second, 10 days after the precastration of the left testis, the animals were exposed to 200r X-irradiation with right testis unshielded. In the third, 10 days after the precastration of left testis, the animals were exposed to 200r X-irradiation with right testis shielded by a 6 mm thick lead housing. In the fourth, animals were exposed to 200r X-irradiation, with right testis shielded and left testis unshielded. At the time of exposure, testes were all pushed backed from the scrotum into the abdominal cavity to receive X-ray treatment, and the irradiated testes were all taken out 10 days after exposure.Statistical analysis of the frequencies of chromosome aberrations obtained here together with our previous data (Chang, Chao, Tan and Liu 1963) shows while either whole body or local testicular region exposure to 200r X-irradiation produces similar effects on the increase of the frequencies of chromosome aberrations, the result with the shielded testis is essentially the same as the controls. This suggests that chromosome aberrations induced by X-irradiation are resulted from the direct effect of X-rays on the chromosomes and the protective function of lead housing renders the testis to prevent from radiation injury to the chromosomes. The data further show that precastration of one testis could hardly affect the frequencies of chromosome aberrations in the other testis retained in the same animal. Hence, it is safe to use 2 testes of a same animal, one for control and the other for experimental purpose, or both for treatment but with ditferent dosages. This information is of special value in the design of experiments to eliminate possible errors due to individual differences, especially when the number of such experimental animal as monkey could not often be very large.更多还原