Abstract
Earlier studies on the biological effects of ionizing radiation at the cellular level revealed that the cell cycle progression was influenced by irradiation, which provided the bases for the concept of "cell cycle checkpoints". On the other hand, the reduction of cell killing was observed when cells were kept under non-growth conditions. The phenomena were named "Liquid Holding Recovery" or "Potentially Lethal Damage Recovery". Studies with variant cell lines also demonstrated that transient cell cycle arrest would rescue the irradiated cells. Taken together with the results on the relationship between the radiation-induced DNA damage and its repair and cell death and its modification, it is suggested that the radiation induced transient cell cycle arrest would afford the cells opportunity to repair certain types of DNA damage, which would cause cell death, and contribute to the cellular recovery.
