1. Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai, China
2. Department of Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai, China
3. Department of Geriatrics, Zhongshan Hospital, Fudan University, Shanghai, China
4. Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai, China
5. Department of Gastroenterology, Endoscopy Center and Evidence-Based Medicine Center, Zhongshan Hospital, Fudan University, Shanghai, China