1. Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, Jilin 130021, China
2. Department of Pediatrics, The First Hospital of Jilin University, Changchun, Jilin 130021, China
3. Endoscopy Center, The China-Japan Union Hospital of Jilin University, 146 Xiantai Street, Changchun, Jilin 130021, China