1. Department of Internal Medicine, Division of Gastroenterology and Hepatology, University of California, Davis, 4150 V St, PSSB 3500, Sacramento, CA 95817.
2. Department of Radiology, University of California, Davis, Sacramento, CA.
3. Department of Pathology and Laboratory Medicine, University of California, Davis, Sacramento, CA.
4. Department of Public Health Sciences, Division of Biostatistics, University of California, Davis, Sacramento, CA.