Affiliation: | (1) Department of Medicine and Division of Gastroenterology, Stanford University School of Medicine, Stanford, CA, USA;(2) Division of Gastroenterology, Palo Alto VA Medical Center, Palo Alto, CA, USA;(3) Division of Gastroenterology and Hepatology, Stanford University School of Medicine, A149, 300 Pasteur Drive, Stanford, CA 94305-5202, USA; |