LATE EFFECTS OF FRACTIONATED X RADIATION IN MICE-FAILURE TO PREVENT NON-THYMIC LYMPHOMAS BY THIGH-SHIELDING
Abstract
Groups of female LAF1 mice were exposed to an X-ray dose of 260 rads given in a single dose (at 11 weeks or 14 months of age) or in 52 weekly doses of 5 rads each (started at 11 weeks of age). A group of the latter animals had one thigh shielded during the irradiation procedure. The incidence of malignant lymphoma, of the generalized nonthymic type, was increased in both of the groups receiving fractionated doses of radiation; thigh shielding did not inhibt leukemogenesis under these conditions. This finding suggests that the mechanisms of radiation induction of thymic and nonthymic lymphoms in mice may differ, since in the former case, shielding of hematopoieic cells reduces lymphoma incidence. Median life span did not differ significantly among the 3 groups of mice irradiated at 11 weeks of age. the median life span for the mice receiving a single dose of 260 rad at 14 months of age (i.e., 28 months) was 5 months longer than that of the group receiving a single dose of 260 rad at 11 weeks of age. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 04, 1962
- Accession Number
- AD0292123
Entities
People
- L.j. Cole
- P.c. Nowell
Organizations
- Naval Radiological Defense Laboratory