Percentage and cycling status of thymocytes obtained from control or irradiated mice. (A) The percentages ± SD of cells recovered from the thymus (2 lobes) of control mice (day 0) or of mice killed on different days after irradiation. The number of mice used per point is shown in parenthesis. The range of absolute thymocyte count recovery for control mice is indicated in the graph. (B) The distribution of thymocytes according to their cycling status. In this experiment, except for six individually analyzed control mice (G₀/G₁ = 90.75 ± 0.86, S = 8.17 ± 0.73, and G₂/M = 1.08 ± 0.16), percentage values were obtained with the labeling of pooled thymocytes from at least three animals per point.