Comparative haematological changes after 15 mev neutron- and X-irradiation. I. Differentiation counts in peripheral blood and bone marrow.

The effect of 15 MeV fast neutrons on blood and marrow cells of young NMRI-mice was compared to that of X-rays after single doses of whole-body irradiation. Using differential cell counts in peripheral blood and bone marrow smears, quantitative data are presented. Complete recovery of peripheral blood and bone marrow cells to control values was not observed. Lymphocytic regeneration was particularly retarded. Irradiation with fast neutrons affected the regneration of marrow cells more severely than with X-rays.