STUDIES ON THE MECHANISM OF ACTION OF THERMAL NEUTRONS IN PRODUCING BIOLOGICAL EFFECTS. II. COMPARATIVE EFFECTIVENESS IN PRODUCING INTESTINAL DAMAGE, LETHALITY, AND MARROW DAMAGE IN RATS

摘要

Animals exposed to lethal doses of neutrons die earlier than animals exposed to equal rem doses of X or gamma rays when.rem is determined on the basis of 30-day lethality. The thesis that this earlier death time might be due to relatively greater damage to the intestine by neutrons was investigated. The RBE of thermal neutrons in terms of X radiation was determined for the Production of lethality, atrophy of the small intestine, and depression of Fe59 uptake by red cells in rats. The values for RBE were 1.4, 1.1, and 1.1, respectively, for the three effects.