Accession Number : AD0777032


Title :   Bone Marrow Response of Beagles to Fractionated Doses of Mixed Gamma-Neutron Radiation.


Descriptive Note : Scientific rept.,


Corporate Author : ARMED FORCES RADIOBIOLOGY RESEARCH INST BETHESDA MD


Personal Author(s) : West,J. E. ; Mitchell,F. A. ; Jones,S. R. ; Witz,J.


Report Date : SEP 1973


Pagination or Media Count : 23


Abstract : Male beagles were bilaterally exposed to mixed gamma-neutron radiation from the AFRRI-TRIGA reactor. The dose rate was 20 rads/minute for all irradiations and midline tissue doses were 215 rads, 225 rads and 240 rads. At each dose approximately one-half of the animals received a single irradiation while the others were given one-fourth the dose each day for 4 consecutive days. The objective of this study was to determine if doses in the median lethal range delivered in four equal fractions at 24-hour intervals were more lethal and more damaging to survival-limiting hematopoietic cell renewal systems than similar unfractionated doses. Single irradiations were the more lethal, first evident at 225 rads and increasing markedly in effectiveness at 240 rads. Radiation-induced changes in bone marrow cellularity were similar after single and fractionated irradiations. (Modified author abstract)


Descriptors :   *Radiation effects, *Bone marrow, Gamma rays, Dogs, Laboratory animals, Experimental data, Dose rate, Radiation dosage, Sublethal dosage, Lethality


Subject Categories : RADIOBIOLOGY


Distribution Statement : APPROVED FOR PUBLIC RELEASE