【摘要】 运用琼脂扩散盒（ADC）培养细胞集落的方法,我们比较了用三种低LET射线——200kVX射线、⁶⁰Coγ射线和20MeV电子束,在两个剂量率（0.35Gy/min和1Gy/min）下,照射淋巴型白血病细胞L7712得到的存活曲线。 细胞在615近交系小鼠和昆明种小白鼠腹腔中的扩散盒中均生长良好。每个扩散盒中植入的细胞数,和细胞集落数的关系呈线性,在两组数据中无明显差异。 研究了200kVX射线对细胞的辐照效应。剂量率为0.35Gy/min时,存活曲线的D₀-1.55（1.45～1.67）Gy,n为0.94（0.88～1.03）,相关系数r=-0.88。而剂量率在1.0Gy/min时,D₀和n分别为1.39（1.30～1.54）Gy和0.90（0.82～1.0）,相关系数r=-0.85。受⁶⁰Coγ射线（0.35y/min）照射后,D₀、n和r分别为1.76（1.60～1.90）Gy,0.96（0.87～1.07）和-0.82。⁶⁰Coγ射线和200kVX射线相比得到的相对生物学效应（RBE）为0.88。20MeV电子束（1.0Gy/min）照后的存活曲线,其D₀和n分别为1.96（1.87～2.07）Gy,0.99（0.94～1.05）,r=-0.93。与200kVX射线相比,RBE等于0.71。更多还原

【Abstract】 Using the agar diffusion chamber （ADC） for colony formation of lymphocytic leuke-mic cells L7712, we compared the survival curves of the cells irradiated by three kindsof low LET radiations-200kV x-rays, ⁶⁰Co gamma rays and 20 MeV electron beamin two rates （0 35Gy/min and 1 0Gy/min）. The cells grew well in ADC both in the peritoneums of 615 inbred mice andKumming white mice. The relationship between the number of cells implanted to eachchamber and the number of colonies formed was shown to be linear. There was no signi-ficant difference between the two sets of data. 200kV x-rays irradiation to cells was studied. The survival curve for a dose rate of0.35Gy/min had a D₀ of 1.55（1.45～1.67）Gy, n of 0 94（0.88～1.03） and correlationcoefficient r=-0.88; while with a dose rate of 1 0Gy/min they were 1.39（1.30-1.54）Gy, 0.90（0.82～1.0） and-0.85 respectively. The D₀, n and r for survival curve after⁶⁰Co irradiation （0.35Gy/min） were 1.76（1.60～1.90）Gy, 0.96（0.87～1.07） and-0.82. The RBE of ⁶⁰Co gamma rays as compared with 200kV x-rays was 0.88. Thesurvival curve for 20MeV electron beam （1.0Gy/min） had a D₀ of 1.96（1.87～2.07）Gyand n of 0.99 （0.94～1.05）, r=-0.93. Its RBE as compared with 200kV x-rayswas 0 71.更多还原