1. Department of Gastroenterology and Hepatology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
2. Department of Gastroenterology and Hepatology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, P.R. China
3. Department of Pathology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China