Yoshimaru H, Otake M, Schull W J, Funamoto S
Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan.
Int J Radiat Biol. 1995 Mar;67(3):359-71. doi: 10.1080/09553009514550411.
The pervasiveness of abnormal brain development caused by prenatal exposure to ionizing radiation is still largely unknown. The relationship between A-bomb radiation dose and two measures of neuromuscular performance, one of grip strength and the other of the fine motor coordination required in repetitive action, is described. A multivariate analysis of covariance was used to evaluate the effect of several covariates, such as prenatal radiation exposure and some physical measurements or IQ adding city and sex as categorical factors. When mentally retarded cases were included, a statistically significant effect of radiation exposure on the grip strength and repetitive-action test scores was seen in the 8-15-week postovulation period, and a statistically suggestive effect at 16-25 weeks postovulation. No effect of radiation exposure on the two test scores was noted for prenatal exposure in either of the aforementioned periods when mentally retarded cases were excluded, but a statistically significant diminution of IQ was noted for exposures > or = 16 weeks postovulation. We discuss, from the biological perspective, the projected standard scores for exposures > or = 16 weeks postovulation, and the possibility of lower IQ, small head and mild mental retardation related to radiation exposures < or = 15 weeks postovulation with mentally retarded cases excluded.
产前暴露于电离辐射所导致的异常大脑发育的普遍性在很大程度上仍不为人知。本文描述了原子弹辐射剂量与两种神经肌肉功能指标之间的关系，其中一项是握力，另一项是重复动作所需的精细运动协调性。采用多变量协方差分析来评估几个协变量的影响，如产前辐射暴露以及一些身体测量指标或智商，并将城市和性别作为分类因素。当纳入智力迟钝病例时，在排卵后8 - 15周期间，辐射暴露对握力和重复动作测试分数有统计学上的显著影响，在排卵后16 - 25周有统计学上的提示性影响。当排除智力迟钝病例时，在上述两个时期中的任何一个时期，产前暴露对这两项测试分数均未显示辐射暴露的影响，但对于排卵后≥16周的暴露，智商有统计学上的显著降低。我们从生物学角度讨论了排卵后≥16周暴露的预计标准分数，以及在排除智力迟钝病例的情况下，与排卵后≤15周辐射暴露相关的智商降低、小头和轻度智力迟钝的可能性。
