[1] Weill Cornell Med Coll, Div Gastroenterol & Hepatol, New York, NY USA
[2] Johns Hopkins, Gastroenterol, Baltimore, MD USA
[3] Gainesvillle Med Ctr, Gastroenterol, Gainesville, FL USA
[4] Oregon Clin, Gastroenterol, Portland, OR USA
[5] Portland Clin, Gastroenterol, Portland, OR USA
[6] Catholic Univ, Digest Endoscopy Unit, Rome, Italy
[7] Locale Modena, Gastroenterol, Modena, Italy
[8] Bogota Gen Hosp, Gastroenterol, Bogota, Colombia
[9] Pompidou Clin, Gastroenterol, Paris, France
[10] Juarez Hosp, Gastroenterol, Mexico City, DF, Mexico
[11] Showa Univ, Northern Yokohama Hosp, Gastroenterol, Tokyo, Japan
[12] Nagasaki Univ Hosp, Dept Gastroenterol & Hepatol, Nagasaki, Japan
[13] Klin Hirslanden, Gastroenterol, Zurich, Switzerland