Fig. 1

Morphological analysis and alveoli size and number in the lungs. A Pathological changes in the lungs (H&E staining magnification × 200) Bar: 100 μm. B Statistics of the mean linear intercept (MLI). C Statistics of the mean alveolar number (MAN). Data are presented as mean ± SD. **P < 0.01 vs. the control group; ^#P < 0.05, ^##P < 0.01 vs. the model group; ^∆∆P < 0.01 vs. the Ambroxol group