1. Department of Gastroenterology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
2. Department of Endocrinology, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
3. Laboratory of Glucose and Lipid Metabolism, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China