Transformation of alisol B 23-acetate in processing of Alisma orientalis Study on extracting process of ethanol extract with hypouricemic effect from Rhizoma Alismatis Comparison on six active constituents between formula granule and traditional decoction of Rehmanniae Decoction of six ingredients Optimization of flash-type extraction technology of alisol B 23-acetate from Alismatis Rhizoma by response surface methodology Simultaneous determination of 11 triterpenoids in Alismatis Rhizoma by RP-HPLC-DAD