1. College of Pharmacy, Kangwon National University, Chuncheon 200-701, Korea
2. College of Pharmacy, Ajou University, Suwon 443-749, Korea
3. Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju 220-701, Korea
4. College of Pharmacy, Inje University, Gimhae 621-749, Korea
5. Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, Korea