1 om . - me ' - ~~ — tae 2 >» purpa, end hypoxia due to enem4a, any one of which may be fatal, Many detailed - desertptions of the pathogenesis of these phenomena have been published (1-4, 12-16). The above picture of radistion syndromes is based on animal experimentation; however, human experience particularly as observed at Riroshina and Nagasaki and in the Marshallese natives has indicated that man probably corresponds quite closely to the general marmalian response outlined above with the exception of some differences in time cf occurrence. The CNS apparently was not observed by the Japanese at Hiroshima and Nagesaki. Cne would not expect it to have been observed since doses to produce this syndrome were well within the area of almost total destruction. The GIS with deaths in the first week are well documented clinically and pathologically as are deaths from the HS. However in the case of man, deaths from infection were most prevalent in the second to fourth weeks (maximun incidence during the third week) and from hemorrhazic phenomena in the third to the sixth weeks (maximum incidence in the fourth week). In the Japanese, after the bembing of Hiroshima and Kegeraki, deaths from radiation injuries were occurring as lete as the seventh week. This is in contrast to other animals where deaths from the acute pkase are uncommon after the 20th day. PROBABILITY OF SURVIVAL AS RELATED TO SYXPTOHS Predictions of the effects of various doses of gamma radietion are essential to military and civil defense planning. If the absolute sensitivity of man to rediation were known, and if it were practical to determine the dose to groups under catastrophe cenditions, a realistic statistical prognosis could be made. However, these predictions cannot be made accurately at the present time. Problezs invcelved with estimation of dose received by the injividual, present real practical difficulties, It is probable that dose estimates will be evailable from dosimetry devices or-from dose contour lines and the position of individuals during exposure. The difficulties of relying heavily on the dose estinates for a single individual are apparent. -The exact position of the individual and the degree o@& shielding DOE ARCHUIVEeS

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