UNCLASSIFIED
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Biology and Medicine
standard doses of homologous or heterologous bone marrow,
Mice that
were exposed to 200 roentgens per day for five days and then given either
type of bone marrow showed increased mortality over the X-ray controls
that were given no bone marrow, indicating a killing effect of foreign
bone marrow under these circumstances.
Erythrocyte life-span studies, in which radioactive chromiumwas
used, indicate that the survival time of erythrocytes (red blood cells)
from irradiated mice given rat bone marrow is shorter than the survival
time of normal rat erythrocytes.
Leukemoid injection in irradiated mice. Mice bearing squamcus
cell carcinomas frequently exhibit blood cells resembling those in mice
with mouse leukemia, and the question arose as to whether these leukemoid
cells would promote recovery of the blood when transplanted into lethally
Xwirradiated mice. A series of mice irradiated at 750 roentgens were ->
injected with either one femur equivalent of bone marrow or.about 200 x 10®
leukemoid leucocytes,
Results indicate that the leukemoid cells may
promote development of all three types of blood elements: white cells,
erythrocytes, and platelets.
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