氧不仅是放射增敏剂,同时亦可视为一种有应用价值的放射防护剂。在呼吸低氧分混合气造成机体暂时低氧状态条件下照射,可使肿瘤周围正常组织氧分压迅速下降,得到一定防护,从而允许给予较常规更高的肿瘤治疗剂量,以期提高治疗比。本文报告实验小鼠在呼吸10.5％低氧混合气条件下照射,以骨髓有核细胞微核形成率为指标所取得的放射防护效应。 Oxygen is not only a radiosensitizer, but it can also be regarded as a useful radioprotector. Exposure to hypoxic conditions caused by the hypoxic mixture can cause the oxygen partial pressure of the normal tissue around the tumor to fall rapidly and provide certain protection, thus allowing a higher dose of conventional tumor treatment to increase the therapeutic ratio. In this article, we reported that experimental mice were exposed to 10.5% hypoxia and the radioprotective effect was obtained using the micronucleus formation rate of bone marrow nucleated cells.