useful link

• American Association For The Study Of Liver Diseases

• American Gastroenterological Association

• Digestive Disease Week 2007

• Doctor's Guide

• International Agency for Research on Cancer

• International Society For Infectious Diseases

• International Union Against Cancer

• Iranian Association of Gastroentrology and Hepatology

• IranMedex

• Medical Council Organization

• Ministry Of Health and Medical Education

• National Cancer Institute

• Research Center for Gastroentrology & Liver Diseases

• Scientiifc Information Database

• Tehran University of Medical Sciences

• The European Association For The Study Of The Liver

• United European Gastroentrology Week

• World Gastroenterology Organisation