AIM To determine the contents of polymethoxylated flavones in Citri Reticulatae Pericarpium from eleven cultivar origins.METHODS HPLC was applied to screening extraction solvents (methanol,anhydrous ethanol,95％ ethanol,ethyl acetate and petroleum ether).Ultraviolet-visible spectrophotometry was adopted in the content determination of polymethoxylated flavones in eighteen batches of samples,nobiletin was taken as a reference substance,and the detection wavelength was set at 330 nm.RESULTS Ethyl acetate exhibited the best extraction effect,so it was selected as extraction solvent.Nobiletin showed a good linear relationship within the range of 3.024-13.104 μg/mL (R2 =0.999 8),whose average recovery was 101.37％ with the RSD of 1.34％.The contents of polymethoxylated flavones had obvious differences among samples from different cultivar origins,which were relatively high from Citrus reticulata ‘ Chachi’,Citrus reticulata ‘ Dahongpao’,Citrus reticulata ‘ Tangerina’,Citrus reticulata ‘ Ponkan’,Citrus reticulata ‘ Kinokuni’and Citrus reticulata ‘ Shiyueju’(more than 0.4％).CONCLUSION This simple and accurate method can effectively eliminate the interference of another flavonoids,which is suitable for the content determination of polymethoxylated flavones in Citri Reticulatae Pericarpium.

Objective To study the value of the technique of "Push-pull traction-relax homingrepeatedly confirmed" in the prevention of bile duct injury in LC. Methods From March 2001-August 2009, we applied this technique in 4800 cases of LC. The technique of "Push-pull traction" showed the structures of in the Calot's triangle. The technique of "relax homing" was to restore the cystic duct,hepatic duct and common bile duct to their original anatomical positions. The technique of "repeatedly confirmed" repeatedly identified the positions of the cystic duct, the common hepatic duct and the common bile duct. Results There was no bile duct injury. Conversion to open surgery happened in 118patients due to difficulties in identifying the Calot's triangle structures, bile duct stones, gallbladder cancer, and gallbladder-duodenal fistula. Conclusions The "Push-pull traction-relax homing-repeatedly confirmed" technique could effectively prevent bile duct injury in LC. The method is simple, easy to master and worthy of promotion.