1 Department of Traditional and Western Medical Hepatology, Third Hospital of Hebei Medical University, 050051 Shijiazhuang, China; Department of Gastroenterology, The Second Hospital of Tianjin Medical University, Tianjin, China.
2 Endoscopy Center, Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
3 Department of Gastroenterology, The Second Hospital of Tianjin Medical University, Tianjin, China. Electronic address: jiangyong-612@163.com.