1. School of Basic Medical Sciences, Tianjin Medical University, Tianjin, P.R. China.
2. Research Center of Basic Medical Science, Tianjin Medical University, Tianjin, P.R. China.
3. The Third Central Clinical College of Tianjin Medical University, Tianjin, P.R. China.
4. Department of Gastroenterology and Hepatology, Tianjin Third Central Hospital, Tianjin, P.R. China.