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Ahnfelt-Rønne I, Nielsen OH, Christensen A, Langholz E, Binder V, Riis P.Ahnfelt-Rønne I, et al. Among authors: nielsen oh.Gastroenterology. 1990 May;98(5 Pt 1):1162-9. doi: 10.1016/0016-5085(90)90329-y.Gastroenterology. 1990.PMID: 1969825