The Relative Effectiveness of Fission Neutrons for Gastrointestinal Damage in Mice: Jejunal Crypt Stem Cell Survival
نویسندگان
چکیده
Mice were unilaterally irradiated in either a fission neutron or gamma ray field at various dose rates. Jejunal crypt stem cell survival was analyzed by the multitarget single-hit survival model, which yielded excellent fitting survival curves. At the 1 percent survival level, gamma rays were found to be 20 percent more effective in destroying cells when delivered in a brief pulse of radiation than when delivered at lower dose rates (40 rads/minute or 250 rads/minute). Increased cell survival was not observed for low dose rate neutrons. D0 values obtained were consistent with the findings of similar studies; however, survival curve intercepts were found to be lower than previous estimates.
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