the different types of circulating blood cslis, esturl imentel observation confirmed thats (3) (b) (c) 3, expere The short-lived white biood-cells: disappeared -or were reduced first, the lymphocytes in less than 24 hours, the yranviocytes within 72 hours. Thé blood platelets (intérucdiets life span) were reduced next--first reductions in rats ¢t about five days. The red blocd cells (Long-lived) were the last to show reductions. In the rat, repeneration wes evident by the fifteenth to elghtcenth day in most cell *ypes except for the. sranvlocytes was still. incomplete by the twenty-fifth day after exposute.e In other species, repeneralio:. may ba slower, The lymphocytes were st&il more crazily reduced after twenty five days than were the other cell types. ke In aninzls receiving large doses of radiaxftn, a’ sharp drop in numbers of red blood cells cccurs around the seventh day after radgfition. This is thought be due to bleeding, nutritional, factors, and possibly to othcr ]jtile-=understeod factors and not entirely to simple destruction to partnt cells. This sudden anemia dces not occur with lever radiotion dosages, 5S, In certain speciss (cnd perheos Gamage is cccompanicd ky ther severe radiagfton sincagulant heparine 7 like substunee dute the circuln: which, tesether with the reducui in en sbnoral tendeney to ase re bleec body as e Whole I haf Q t Oe ee 8 ne SUmuerise but very important tee Ge oi 5 na bo G 5) C3 ry pe re fle ta POE OT AF A i whlatolcts, results - Repeated Gmali,necceeer Doses t2 the enareren> The experimenta ad clots shovwly etd since if is coronie radiation reveatercly received in onall deses which is the commonest So.m of raciation exposure in man. Ip is clear, horcver, the. within limits3 the effect i . chronic radiation definitely incrcaces the incidence of leukemin ts enters. & 4 i) m Q Q ta 3 oo a? 8 e eo) ton ao a “ i o {f ee aa pele fe {-te 3Qa [ote is of great importance regardless of how sm ct = Q Ny of chronic redietion is cumulative and thyatthe tote) docage rectived by an organisn Mirely, after upparent recovery from chronic radiation, injery te the blcod-fermins tissues and sevcrei. edDnormelities uuy develop even after raciation has vcen Giscontinued, Radiation to a Local. area of the Body It has been the subject of much controversy thether or not local sadiatio: mAY, in some direct way, damage hemopoietic tissue cutside the Bield of radiaifon. Local