Transgastric cholecystectomy: transgastric accessibility to the gallbladder improved with the SEMF method and a novel multibending therapeutic endoscope. - Sumiyama K; Gostout CJ; Rajan E; Bakken TA; Knipschield MA; Chung S; Cotton PB; Hawes RH; Kalloo AN; Kantsevoy SV; Pasricha PJ (Gastrointestinal endoscopy, 2007)