Abstract
Review of the data accumulated at Nagasaki University and ABCC during the past 20 years revealed 156 cases of aplastic anemia.
The risk of aplastic anemia among Atomic-bomb survivors did not show statisticaly significant increase.
2 cases of acute leukemia among proximally exposed survivors showed temporal severe decrease of leucocyte count immediately following Atomic-bomb explosion.
8 cases of specific anemia among proximally exposed persons during about 1949∼1955 were discovered. These cases showed pancytopenia of peripheral blood and blast cell focus in some cases or acute myelofibrosis in other cases in bone marrow.
It seems that the bone marrow of Atomic-bomb survivors who was exposed to heavy dosis of radiation was one of preleukemic status.
