1. Department of Gastroenterology, The Seventh Medical Center of PLA General Hospital, Beijing, China
2. Department of Laboratory, The Seventh Medical Center of PLA General Hospital, Beijing, China
3. Chinese PLA General Hospital, Beijing, China
4. Department of Medicine/GI Division, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
5. Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China
6. State Key Laboratory of Membrane Biology, School of Medicine, Tsinghua University, Beijing, China