American Gastroenterological Association Organization of physicians, researchers and educators whose primary practice or research involves the functions and disorders of the digestive system
Crohn's and Colitis Foundation American organization focused on improving the quality of life of people with Crohn's disease and ulcerative colitis through research
American Liver Foundation Provides information on liver diseases, as well as advocacy for education, treatment and research funding.
American College of Physicians Web site of the American College of Physicians, the leading professional organization for internal medicine.