超氧化物歧化酶（ＳＯＤ）是超氧自由基（Ｏ_２）的天然清除剂，具有抗辐射作用~［１］，双歧杆菌具有清除Ｏ_２~－及提高宿主对放射线的耐受性~［２］。本文采用７Ｇ６０ＣＯγ射线对小鼠进行全身照射，并于照射前后分别腹腔注射ＣｕＺｎ－ＳＯＤ及双歧杆菌，最后通过小鼠外周 Superoxide dismutase (SOD) is a natural scavenger of superoxide radical (O 2), has anti-radiation effect [1], Bifidobacterium has the ability to scavenge O 2 ~ - and improve the tolerance of the host to radiation ~ [2 ]. In this paper, 7G60COγ rays were used to irradiate the whole body of mice and intraperitoneally injected with CuZn-SOD and Bifidobacterium before and after irradiation. Finally,