Figure 1: Mean percentage of positive cells ± standard deviation for CCSP, Surfactant B, CD24, CD44v6, and CD73 in the upper and lower lung lobes of the control (non-irradiated, 0 Gy) rats at 4 weeks of age. CCSP: Clara cell secretory protein for Clara cells, Surf B: surfactant B for type II pneumocytes. The percentage of positive cells in the upper lobe was compared to the percentage of the positive cells in the lower lobe for the same marker. Significance; *p<0.05 and ** p<0.001.