1. Peking University Hepatology Institute Peking University People's Hospital Beijing China
2. Division of Gastroenterology and Hepatology University of Michigan Ann Arbor Michigan USA
3. National Center for International Cooperation on Translational and Clinical Research Peking University Health Sciences Center Beijing China
4. GI Section VA Ann Arbor Healthcare System Ann Arbor Michigan USA
5. Department of Radiology Peking University People's Hospital Beijing China