Multifractionation of 60Co gamma-rays reduces neoplastic transformation in vitro.
Multifractionation of 60Co gamma-rays reduces neoplastic transformation in vitro.
复制标题
60Co 伽马射线的多重分割可减少体外肿瘤转化。
DOI：
10.1093/carcin/5.2.193
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发表时间：
1984
期刊：
影响因子：
4.7
通讯作者：
M. M. Elkind
中科院分区：
文献类型：
--
作者：
Colin K. Hill;A. Han;A. Han;Franco M. Buonaguro;M. M. Elkind;M. M. Elkind
用总剂量为25~300rad的~(60)Coγ射线照射小鼠胚胎10T_(1/2)细胞，观察了不同剂量、不同分割数目和不同分割间隔的照射后细胞的成瘤率。在所研究的总剂量范围内(25-300拉德)，将活跃生长的10T 1/2细胞以每天五次等剂量的伽马射线照射，而不是一次照射，会导致转化频率显著降低。感应曲线的初始部分很好地符合一条直线。每天五次曝光的直线斜率大约比单次曝光的斜率小3倍。进一步增加分割间隔至48小时，或进一步减少每部分的剂量，可进一步降低肿瘤转化的发生率。我们的观察结果与60Co伽马射线长时间照射引起的亚相变损伤的净“无误差”修复是一致的。
Incidences of neoplastic transformation of 10T 1/2 cells, derived from a C3H mouse embryo, were measured following irradiation of cells with 60Co gamma-rays delivered in single total doses, from 25 to 300 rads, or in different numbers of fractions and with different time intervals between fractions. Throughout the range of total doses that was examined (25-300 rads) exposure of asynchronous, actively growing 10T 1/2 cells to a dose of gamma-rays in five equal daily fractions, rather than in a single exposure, results in a significant reduction in transformation frequency. The initial part of the induction curve fits a straight line quite well. The slope of the line for five daily fractions is approximately 3-fold less steep than that for single exposures. A further increase in the interfraction interval, to 48 h, or further reductions in the dose per fraction, led to additional decreases in the incidence of neoplastic transformation. Our observations are consistent with a net 'error-free' repair of subtransformation damage as a result of protracted irradiation with 60Co gamma-rays.