title: Mammalian cell survival response following irradiation with 4 MeV X rays or accelerated helium ions combined with hyperthermia.
abstract: The effects of hyperthermia on Chinese hamster ovary cell radioresponse were studied using either 4 MeV x rays or accelerated helium ions. Both pre-and postirradiation hyperthermic doses act to decrease the slope of the x-irradiation survival curve in a temperature-dependent manner, while the extrapolation number does not change appreciably. Pre-irradiation hyperthermic treatment has only a slightly greater dose-modifying effect than similar postirradiation hyperthermia. For cells irradiated with helium, pre-irradiation at 43 degrees C (1 hr.) changes the radiation survival curve slope and also the extrapolation number, implying that hyperthermia may act more readily to enhance lethal x-ray damage than lethal helium damage, while having a similar effect on the accumulation of sublethal damage for both of these radiations.
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000528:radiation effects*; D002478:Cells, Cultured; D006224:Cricetinae; D004735:Energy Transfer; D006371:Helium; D006358:Hot Temperature; D011829:Radiation Dosage; D011830:Radiation Effects; D013997:Time Factors; D014965:X-Rays
chemical_list: D006371:Helium