Okladnikova N D, Sumina M V, Pesternikova V S, Azizova T V, Kabasheva N Ia
Klin Med (Mosk). 2007;85(10):21-6.
The authors present a brief review of the results of many-year research into the clinical effects, consequences, and outcomes of occupational external gamma-radiation in a wide dose range. Chronic external gamma-radiation does not cause radiation-induced effects when it does not exceed the limit of the yearly dose for personnel. Tendency for cytopenia in peripheral blood (leukothrombocytopenia) appears when the maximum yearly dose is not less than 25 to 50. The conventional threshold for the development of chronic radiation disease is a maximum yearly dose of 0.73 Gy, and total (accumulated) dose of 1.43 Gy. Long-term consequences of exposure to high-dose radiation are incomplete recovery of the hemopoietic system (moderate general bone marrow hypoplasia or partial hypoplasia of granulocytopoiesis), compensated at the level of the organism, as well as a defect in the reestablishment of cell-mediated immunity in cases of high power of radiation (more than 2.5 Gy per year) and high accumulated dose (more than 4.5 Gy). Consequences of acute radiation disease were radiation-induced cataracts (a dose of not less than 4 Gy), and incomplete reestablishment of hemopoietic system according to myelograms, in sole cases. The indicator of the fact that an exposure to radiation took place is an elevated frequency of stable chromosomal aberrations in immunocompetent cells--lymphocytes--even after 45 to 50 years after the contact was discontinued. Local dermal lesions, the range and severity of which depend on the degree of the lesion in the acute period, remain long after local radiation exposures.
作者简要回顾了多年来对宽剂量范围内职业性外照射γ射线的临床效应、后果及结局的研究结果。当慢性外照射γ射线剂量未超过人员年剂量限值时,不会引起辐射诱发效应。当年最大剂量不少于25至50时,外周血会出现血细胞减少倾向(白细胞血小板减少)。慢性放射病发生的传统阈值是年最大剂量0.73 Gy,总(累积)剂量1.43 Gy。高剂量辐射暴露的长期后果是造血系统恢复不完全(中度全骨髓发育不全或粒细胞生成部分发育不全),在机体水平得到代偿,以及在高辐射剂量(每年超过2.5 Gy)和高累积剂量(超过4.5 Gy)情况下细胞介导免疫重建存在缺陷。急性放射病的后果是辐射诱发白内障(剂量不少于4 Gy),仅在个别情况下根据骨髓象造血系统恢复不完全。即使在接触停止45至50年后,有辐射暴露这一事实的指标是免疫活性细胞——淋巴细胞中稳定染色体畸变频率升高。局部皮肤损伤在局部辐射暴露后会长期存在,其范围和严重程度取决于急性期损伤程度。