AOD of Smad3 protein positive expression in the mucosa, submucosa, and muscularis between the two groups
| Control group (n=13) | Observed group (n=37) | P value | |
| Mucosa layer | 0.263 (0.243, 0.298) | 0.550 (0.516, 0.612) | 0.000 |
| Submucosa | 0.238 (0.211, 0.267) | 0.387 (0.366, 0.404) | 0.000 |
| Muscular layer | 0.198 (0.187, 0.211) | 0.319 (0.289, 0.329) | 0.000 |
AOD, average optical density; Smad3, mothers against decapentaplegic homolog 3.