Different exposure conditions result in different sensitivities of proliferating cells to ionizing radiation.

<p>(A) Clonogenic survival of various human cell lines exposed to acute ¹³⁷Cs γ-irradiation (1 Gy Gy/min). Surviving fractions are expressed relative to the plating efficiencies of non-irradiated cells. Values represent the mean ± SD of three independent experiments. (B) Cell proliferation of various human cell lines under chronic γ-irradiation conditions. Cells exposed to 0.347 mGy mGy/min (grey circles) are compared to unirradiated controls (white circles).