Abstract
Mice were exposed to 200 r of X-rays 25-70 min. after intraven. injn. of one of the following compounds: cysteine, glutathione, thiocholine, thiourea, ascorbic acid, methylene blue, and vit. B12. Feulgen-stained prepns.of bone marrow, fixed 17-19 hrs. after the whole body radiation, showed no decrease in abnormal mitoses in the anaphase stage. Similar prepns, from mice irradiated in a gas mixture of 6-7% O2 in N2 showed a decrease in abnormal mitoses.