[Effects of low radiation doses on Chinese hamster cells].

The induction of cytogenetic damages after irradiation with single dose of gamma-rays (0.1-2 Gy) have been studied. It is shown non-linear curve for the induction of chromosome aberrations, detected by anaphase method. After irradiation in S-stage of the cell cycle at dose below 0.2 Gy the cells were more radiosensitive than after irradiation with doses 0.3-2 Gy. Between the phases of high radiosensitivity and radioresistance the reversal dose-effect relation was observed. This phenomenon was not marked for the cells after irradiation in G2-stage of the cell cycle. It is possible, this results could reflect an induced radioresistance at low dose of irradiation.