1. Department of Gastroenterology and Hepatology, Institute of Digestive Disease, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
2. Department of Gastroenterology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, P.R. China
3. Department of Pulmonary and Critical Care Medicine, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China