[1] Univ Chicago, Med Ctr, Chicago, IL 60637 USA
[2] Hosp Univ Penn, Philadelphia, PA 19104 USA
[3] Hosp Claude Huriez, Lille, France
[4] Mt Sinai Med Ctr, New York, NY 10029 USA
[5] Univ Kiel, Kiel, Germany
[6] Tel Aviv Sourasky Med Ctr, Tel Aviv, Israel
[7] Atlanta Gastroenterol Assoc, Atlanta, GA USA
[8] Clin Leverkusen, Leverkusen, Germany
[9] Greater Cincinnati Gastroenterol Assoc Inc, Atlanta, GA USA
[10] Univ Western Ontario, London, ON, Canada
[11] Centocor Inc, Malvern, PA 19355 USA
[12] Univ Hosp Gasthuisberg, B-3000 Louvain, Belgium