【摘要】 目的 针对载人深空探测急需解决的航天员辐射限值和风险评估问题，模拟太阳粒子事件辐射探究骨髓损伤效应。方法 针对太阳粒子事件（主要成分是质子）特点，利用90兆电子伏（MeV）质子在0、0.1、0.3、0.5、1、2 Gy剂量下分别照射48只BALB/c小鼠，照射后3和7 d，血常规计数仪检测外周血变化，吉姆萨染色检测骨髓粒细胞和红细胞比例，流式细胞仪检测骨髓干细胞比例、细胞亚群比例和凋亡变化，并分析剂量与损伤指标的量效关系及阈值。结果 在0.1～2 Gy的剂量范围内，照射后3和7 d，随剂量增加，外周血白细胞计数、淋巴细胞数降低，骨髓粒细胞和红细胞比例、骨髓细胞亚群比例异常；照射后7 d，血小板数下降，具有显著变化的最小剂量为0.5 Gy；获得具有量效关系的模型13个；ED25、ED50和ED63的最小值分别为0.25、0.58和0.76 Gy。结论 获得了质子导致小鼠骨髓损伤的量效关系模型13个，剂量阈值为0.25～0.76 Gy。更多还原

【Abstract】 Objective To explore the effect of bone marrow injury by simulating the radiation from solar particle events in order to address the radiation limit and assess risks during manned deep space exploration. Methods In line with solar particle events(the main component was protons),BALB/c mice(48 mice per group)were irradiated with 90 MeV protons at the doses of 0,0.1,0.3,0.5,1 and 2 Gy. At 3 and 7 days after irradiation. Routine blood counters were employed to detect peripheral blood changes,Giemsa staining was used to detect the ratio of granulocytes to erythrocytes in bone marrow,and flow cytometry was adopted to detect the proportion of bone marrow stem cells,cell subsets and apoptosis before the dose-response relationship and threshold were analyzed. Results In the dose range of 0.1 to 2 Gy,the number of peripheral blood white blood cells and lymphocytes decreased at 3 and 7 days after irradiation and the ratio of granulocytes to erythrocytes in bone marrow and bone marrow cell subsets were abnormal as the dose increased. Seven days after irradiation,the platelet count decreased. The minimum dose that caused significant changes was 0.5 Gy,13models with dose-response relationships were obtained,and the minimum values of ED25,ED50 and ED63 were 0.25,0.58and 0.76 Gy,respectively. Conclusion A total of 13 dose-response relationship models of proton-induced bone marrow injury in mice have been obtained,and the dose threshold of proton-induced bone marrow injury ranges from 0.25 to 0.76 Gy.更多还原