X、γ射线在洋葱根尖细胞中的微核诱发率

The Frequencies of Micronuclei Induced in the Root-tip Cells of Onion Seedlings by ^(60)Co γ-ray and X-ray.

目的 了解X、γ射线作为评价辐射相对生物效应的参考辐射的重要性。方法 用6 0 Coγ射线以及X射线照射洋葱种苗后 ,观察根尖细胞中的微核诱发率的差异。结果 6 0 Coγ射线的微核诱发率为 (3 .41± 0 .3 0 ) %·Gy- 1(±标准差 ) ,X射线的微核诱发率为 (5 .2 3± 0 .3 8) %·Gy- 1 。以6 0 Coγ射线和X射线作为参考辐射时 ,某反应堆中子照射洋葱种苗后在根尖细胞中诱发微核的相对生物效应值分别为RBEn ,γ=3 3 .7± 8.4和RBEn ,X=2 2 .0± 5 .4。结论 不同的参考辐射 ,对同一辐射来说 ,其相对生物效应值有十分显著的差异 ,论及辐射的相对生物效应时必须指明参考辐射。

Objective To best understand the importance of X- and γ-ray radiations as the reference radiation used in relative biological effectiveness (RBE) of radiations. Methods The difference of the frequencies was observed of micronuclei induced in the root-tip cells of onion seedlings by 60Co γ-ray and X-ray. Results The frequencies of micronuclei induced by 60Co γ-ray and X-ray are (3.41±0.30) and (5.23±0.38) %·Gy -1 (±standard deviation), respectively. As an example, the RBE values of neutrons from a nuclear reactor are RBE n,γ=33.7±8.4 and RBE n,X=22.0±5.4 when the reference radiations are 60Co γ-ray and X-ray, respectively. Conclusion For the same radiation, the difference of its RBE values is very significant when the reference radiations are different. It is very important to point out the reference radiation when treat of the RBE values.