Director of Department of Gastroenterology and Hepatology, First Medical Center of Chinese PLA General Hospital and Chinese PLA Medical College. President of Chinese Society of Digestive Endoscopology (CSDE)，Chinese Medical Association； Vice President of Endoscopy Branch of Chinese Medical Association； President of Digestive Endoscopy Branch，Beijing Medical Association； President of Digestive Endoscopy Branch，Beijing Physicians Association Editor-in-chief of Chinese Journal of Gastroenteroscopy Electronics； Vice-President of Chinese Journal of Digestive Endoscopy.