Affiliation: | (1) Department of Internal Medicine, Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea;(2) Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea;(3) Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea;(4) Division of Gastroenterology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Irwon-dong 50, Gangnam-Gu, Seoul, Korea; |