OER and RBE for 125I and 192Ir at low dose rate on mammalian cells.
The oxygen enhancement ratio (OER) for 125I and 192Ir as well as the relative biological effectiveness (RBE) at low dose rates (40-80 cGy h-1) were determined for B16 melanoma cells in culture. The OER was found to be 2.1 +/- 0.03 for 125I and 2.7 +/- 0.04 for 192Ir. The RBE for 125I relative to 192Ir was determined as 1.8 +/- 0.03 under aerated conditions and as 2.4 +/- 0.03 under hypoxia.
Department of Medical Physics, Groote Schuur Hospital, University of Cape Town, South Africa.
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D000818:Animals; D004307:Dose-Response Relationship, Radiation; D066298:In Vitro Techniques; D007457:Iodine Radioisotopes / Q000008:administration & dosage*; D007496:Iridium Radioisotopes / Q000008:administration & dosage*; D008322:Mammals / Q000528:radiation effects; D008546:Melanoma, Experimental / Q000532:radiotherapy; D051379:Mice; D010100:Oxygen / Q000494:pharmacology*; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000528:radiation effects*
D007457:Iodine Radioisotopes; D007496:Iridium Radioisotopes; D011838:Radiation-Sensitizing Agents; D010100:Oxygen