Otake M, Schull W J
Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan.
Radiat Res. 1990 Jan;121(1):3-13.
This paper investigates the quantitative relationship of ionizing radiation to the occurrence of posterior lenticular opacities among the survivors of the atomic bombings of Hiroshima and Nagasaki suggested by the DS86 dosimetry system. DS86 doses are available for 1983 (93.4%) of the 2124 atomic bomb survivors analyzed in 1982. The DS86 kerma neutron component for Hiroshima survivors is much smaller than its comparable T65DR component, but still 4.2-fold higher (0.38 Gy at 6 Gy) than that in Nagasaki (0.09 Gy at 6 Gy). Thus, if the eye is especially sensitive to neutrons, there may yet be some useful information on their effects, particularly in Hiroshima. The dose-response relationship has been evaluated as a function of the separately estimated gamma-ray and neutron doses. Among several different dose-response models without and with two thresholds, we have selected as the best model the one with the smallest x2 or the largest log likelihood value associated with the goodness of fit. The best fit is a linear gamma-linear neutron relationship which assumes different thresholds for the two types of radiation. Both gamma and neutron regression coefficients for the best fitting model are positive and highly significant for the estimated DS86 eye organ dose.
本文研究了由DS86剂量测定系统所提示的广岛和长崎原子弹爆炸幸存者中电离辐射与晶状体后囊混浊发生之间的定量关系。在1982年分析的2124名原子弹爆炸幸存者中，有1983人（93.4%）可获得DS86剂量。广岛幸存者的DS86比释动能中子成分远小于其对应的T65DR成分，但仍比长崎的同类成分高4.2倍（6戈瑞时为0.38戈瑞，而长崎在6戈瑞时为0.09戈瑞）。因此，如果眼睛对中子特别敏感，那么关于中子效应可能仍有一些有用信息，尤其是在广岛。剂量反应关系已根据分别估算的γ射线和中子剂量进行了评估。在几种不同的有无两个阈值的剂量反应模型中，我们选择了与拟合优度相关的χ²最小或对数似然值最大的模型作为最佳模型。最佳拟合是一种线性γ射线 - 线性中子关系，该关系假定两种辐射有不同的阈值。对于估算的DS86眼部器官剂量，最佳拟合模型的γ射线和中子回归系数均为正值且高度显著。
