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关于氧在放射线中的作用,很早就有人提出。1921年,Holthusen已注意到:放射线对蛔虫卵的杀伤效能与照射是否有氧关系很大,Petri于1923年通过研究射线对蔬菜种子的作用时,发现放射敏感性和氧的存在之间有一定的相关性。如许多实验都证实:当受照细胞的存活水平达到同一效应时,乏氧所需的X线剂量为有氧的3倍。所以人们把达到同一生物效应时,乏氧时所需剂量/有氧时所需剂量=氧增强比(OER)。氧增强比值较稳定,对稀疏电离辐射X线或γ线而言,OER=2.5～3.0对致密电离辐射如α粒子,OER为1.0,也就是说α粒子照射生物体时,不存在氧效应问题。介于二者之间的中子OER约为1.6。
The role of oxygen in radiation has been raised long ago. In 1921, Holthusen had noticed that the killing effect of radiation on Ascaris eggs was closely related to whether there was oxygen in the irradiation. When Petri studied the effects of radiation on vegetable seeds in 1923, it was found that there was a certain correlation between the radiosensitivity and the presence of oxygen. The relevance. For example, many experiments have confirmed that when the survival level of irradiated cells reaches the same effect, the X-ray dose required for hypoxia is 3 times that of aerobic. So when people achieve the same biological effect, the required dose for hypoxia/the required dose for aerobic = the oxygen enhancement ratio (OER). The oxygen-enhanced ratio is relatively stable. For sparsely ionizing radiation X-rays or γ-rays, OER = 2.5 to 3.0. For dense ionizing radiation such as alpha particles, the OER is 1.0, which means that there are no oxygen effects when alpha particles are irradiated to organisms. . The neutron OER between the two is about 1.6.