A high performance liquid chromatography-electrospray ionization mass spectrometry- charged aerosol detection ( HPLC-MS-CAD) method was established for the simultaneous quantitative analysis of four Lignans in Magnoliae Flos extract. The components were separated on a YMC-Pack ODS-A column (250 mm× 4. 6 mm, 5 μm) by gradient elution with methanol and water as the mobile phase at aflow rate of 1. 0 mL/min. Then the elution solution was routed into MS equipment at a flow rate of 0. 3 mL/min and CAD detector at a flow rate of 0. 7 mL/min by a split ratio of 3:7 for the further detection. The column temperature was 25 ℃ and the detection wavelength was 278 nm. A method was developed for the quantitative analysis of muti-components by single maker ( QAMS) to determine pinoresinol dimethylether, magnoli, 1irioresinol B dimethylethe and epi-magnoli A . Magnoli was selected as internal standard and the relative correction factors ( RCF) of the four Lignans were calculated. The contents of the four Lignans in Magnoliae Flos extract were determined by both external standard method and QAMS. The QAMS method was evaluated by comparison of its assay result and that of external standard method. Under the selected chromatographic condition, the limits of detection of pinoresinol dimethylether, magnoli, lirioresinol B dimethylethe and epi-magnoli A were 0. 34, 0. 55, 0. 50 and 0. 58 mg/L, respectively, while the linear range were within 6. 8-270 mg/L, 11-546 mg/L, 2. 0-101 mg/L and 2. 3-116 mg/L. The recoveries ( n=9 ) were 98. 2%-99. 5%, and the correlation coefficient were 0 . 9995-0 . 9998 . No significant differences were found between the quantitative results of external standard method and QAMS method. The developed method is accurate, feasible, and can be used for quality evaluation of Magnoliae Flos .

Objective To examine the association between social isolation and cognitive function among the elderly living in the communities of Daqing city.Methods A total of 981 community residents aged 60 years or over,were surveyed with a questionnaire.Both Lubben Social Network Scale-6 (LSNS-6) and Montreal Congnitive Assessment (MoCA) Changsha Versions were used to respectively screen the status of social isolation and cognitive function,on these elderly.Results The average age was 71 years old for the 981 study participants.10.60％ (104/981) of the participants were assessed as having the status of social isolation,9.48％ (93/981) as having marginal family ties and 13.97％ (137/981) as having marginal friendship ties.Results from the multivariate linear regression analysis revealed that participants with higher scores of LSNS-6 presenting better cognitive function score,with a partial regression coefficient as 0.10 (P＜0.01).The MoCA scores in participants with social isolation (20.38 ± 5.54) were significantly lower than the ones without social isolation (22.10 ± 5.01) and the difference was statistically significant (P＜0.01).Social isolation was significantly related to the domain scores on visuo-spatial constructional executive functions (P=0.02),naming (P=0.03),language (P=0.01) and delayed memory functions (P＜0.01),but not with other domains as concentration (P=0.33),orientation (P=0.27) or abstraction (P=0.49).Conclusion The findings suggested that social isolation was mainly caused by the lack of friendship ties and associated with cognitive function and among the elderly in Daqing city,Heilongjiang province.