title: [Effects of irradiation on the lip mucosa in the mice as a function of rate. Comparison with the effect of fractionation].
abstract: We have investigated the effect of single doses delivered at various dose rates on the mouse lip mucosa biological system. The dose rates were: 642, 76.8, 14.1, 2.9 and 1.5 Gy/h. The incidence of desquamation in the different groups of mice was used for constructing dose effect curves. The dose leading to desquamation in 50% of the animals (ED50) was obtained by probit analysis. These ED50 were 16.5, 16.7, 19, 30.2 and 33.5 Gy for the respective dose rates. Fractionated irradiations have also been performed in the same biological system (separately published), and we have therefore been able to compare the fractionated and low dose rate irradiations. The recently published model of Dale was used for this comparison. With that mathematical approach a alpha/beta value of 7.4 Gy and a half time of repair of sublethal damage of 47 minutes have been derived. These results compare well with others from the literature on biological systems with similar characteristics (rapidly proliferating systems).
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D004890:Erythema / Q000209:etiology / Q000628:therapy; D008046:Lip / Q000528:radiation effects*; D051379:Mice; D009092:Mucous Membrane / Q000528:radiation effects
vernacular_title: Effets d'une irradiation sur la muqueuse labiale chez la souris en fonction du débit. Comparaison à l'effet du fractionnement.