Storer J B, Fry R J
Biology Division, Oak Ridge National Laboratory, TN 37831-8077, USA.
Radiat Environ Biophys. 1995 Mar;34(1):21-7. doi: 10.1007/BF01210541.
Male and female hybrid BCF1 (C57BL/6 Bd x BALB/c Bd) were exposed to total neutron doses of 0.06, 0.12, 0.24, and 0.48 Gy in fractions over a period of 24 weeks. The fractionation regimens were: 24 weekly fractions of 0.0025 Gy, 12 fractions of 0.01 Gy every 2 weeks, 6 fractions of 0.04 Gy every 4 weeks, and 3 fractions of 0.16 Gy every 8 weeks. In order to detect any change in susceptibility with age over the period of exposures from 16 weeks to 40 weeks of age, mice were exposed to single doses of 0.025, 0.05, 0.10, and 0.2 Gy at 16 and 40 weeks of age. These experiments were designed to test whether the initial parts of the dose-response relationships for life shortening and cancer induction could be determined economically by using fractionated exposures and whether or not the initial slopes were linear. The conclusions were that for life shortening and most radiogenic cancers, the dose-effect curves are linear and that fractionation of the neutron dose has no effect on the magnitude of the response of equal total doses over the range of doses studied. The ratio of such initial slopes and comparable linear initial slopes for a reference radiation should provide maximum and constant relative biological effectiveness values.
将雄性和雌性杂交BCF1（C57BL/6 Bd×BALB/c Bd）在24周内分多次接受总中子剂量为0.06、0.12、0.24和0.48 Gy的照射。分割方案如下：每周24次，每次0.0025 Gy；每2周12次，每次0.01 Gy；每4周6次，每次0.04 Gy；每8周3次，每次0.16 Gy。为了检测在16周龄至40周龄的暴露期间易感性随年龄的任何变化，在16周龄和40周龄时给小鼠单次给予0.025、0.05、0.10和0.2 Gy的剂量。这些实验旨在测试是否可以通过使用分次照射经济地确定寿命缩短和癌症诱导的剂量反应关系的初始部分，以及初始斜率是否呈线性。结论是，对于寿命缩短和大多数辐射诱发的癌症，剂量效应曲线是线性的，并且在研究的剂量范围内，中子剂量的分割对相等总剂量的反应幅度没有影响。这种初始斜率与参考辐射的可比线性初始斜率之比应提供最大且恒定的相对生物效应值。
