It has been confirmed clearly that gastric bypass operation could be used for tbe treatment of type 2 diabetes mellitus.However,the curative mechanism underlying this therapy remain unclear up to now.Referencing the curative mechanisms research progress from domestic and abroad,the possible mechanism is considered as the secretion of gastrointestinal hormones can be changed after gastric by~ss operation,which has altered the normal anatomy structure of the gastrointestinal,and so as to the situation of type 2 diabetes mellitus can be controlled.This review will summarize recent papers related to mechanism research about the gastric bypass operatiou for the treatment of type 2 diabetes mellitus.

Objective To discuss the safety and feasibility of percutaneous transhepatic biliary preset implantation of after-loading radiotherapy catheter in treating bile duct carcinoma of ampulla.Methods A total of 10 patients with carcinoma of ampulla were collected.After percutaneous transhepatic biliary stent implantation was accomplished,the after-loading radiotherapy catheter was inserted via the guide wire.Based on the lesion's location,the positioning of both the catheter tip and the simulation radioactive source implanted through catheter was conducted.Each time before irradiation,the positions of the catheter and the radioactive source were reset under CT or fluoroscopic guidance in order to ensure that the lesion could get adequate internal irradiation dose.Results Percutaneous transhepatic biliary implantation of after-loading radiotherapy catheter and the positioning of simulation radioactive source were successfully accomplished in all 10 patients,and the total internal irradiation dose was completed within 5-7 days after catheter implantation.No severe complications occurred during the whole therapeutic process.Conclusion The technology of percutaneous transhepatic biliary preset implantation of after-loading radiotherapy catheter is safe and feasible,it carries high success rate with less complications.This therapy can improve the patency rate of biliary stent,and,as a palliative treatment,it is suitable for patients with carcinoma of ampulla.This treatment is worthy of application and promotion.

Objective To assess the efficiency and methods of the interventional management in acute mesenteric venous thrombosis (AMVT). Methods Fifteen patients with AMVT who diagnosed by imageology were treated by interventional procedures. Eight patients were treated by transcatheter superior mesenteric artery thrombolysis with urokinase, 5 cases by percutaneous transhepatic treatment, 2 cases by transjugular intrahepatic portosystemic shunt approach. Results The technical success was achieved in all the 15 cases without complications. The majority of the thrombus was cleared by interventional procedures and flow restorated on the angiograms. All the patients with follow-up from 10 to 22 months showed no recurrence. Conclusion The minimally invasive interventional techniques are safe and effective in the treatment of mesenteric venous thrombosis without necrosis.