1. Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
2. Assistant Professor of Medicine, Digestive Diseases Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
3. Associate Professor, Digestive Diseases Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
4. Professor, Digestive Disease Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran