Affiliation: | 1. Division of Gastroenterology and Hepatology, Department of Medicine, Northwestern Feinberg School of Medicine, Chicago, Illinois;2. Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;3. Division of Gastroenterology, University of California San Diego, La Jolla, California;4. Division of Gastroenterology, Cleveland VA Medical Center and University Hospitals, Case Western Reserve University, Cleveland, Ohio |