Study on effect of oligochitosan in promoting intestinal absorption of protoberberine alkaloids in extracts from Corydalis saxicola total alkaloids Determination of palmatine hydrochloride in Gymnospermium altaicum by HPLC Determination of palmatine hydrochloride in Gymnospermium altaicum by HPLC Determination of palmatine hydrochloride and berberine hydrochloride in Chinese Mahonia Stem from different habitats by HPLC Simultaneous determination of seven alkaloids in Cuyanhusuo Granule by RP-HPLC Comparison on content differences of four bioactive compounds in different Wujiwan decoction by HPCE internal standard method