A reverse phase HPLC-ELSD method for the determination of ginsenoside Rg1 in the rootof Panaa pseudo-ginseng var. notoginseng (Burkill) Hoo et Tseng was reported. Chromatographic condi-tions: Shim-pack CLC-ODS column (6.0 mm×150 mm)； acetonitrile-water (30: 70) as the mobilephase； Shimadzu LC-6A with SEDEX-55 ELSD detector. The method was found to be simple and accuratewith recovery rate of 100. 50％ and RSD= 1.82 %. The established UV spectrophotometric determinationof total saponins in P. pseudo-ginseng var. notoginseng was also tried and gave an accurate result coinci-dental with that of the HPLC results. The recovery rate was 101.50%， and RSD=1. 44%. It seemed thatboth methods can be used reliably for the quality control of P. pseudo-ginseng var. notoginseng.

Objective To establish a new method, applying high resolution melt, to discriminate the VEB-3 hypotype from the clinical gram negative isolates. Methods From January to December 2003,292 consecutive and non-repetitive gram-negative bacteria producing VEB extended spectrum β-lactamase (ESBL) were collected. Extract the DNA of clinical gram negative isolates with phenol-chloroform. PCR was performed to amplify the VEB gene with the DNA being template. After that, we amplify the fragment of VEB gene containing the position 168. Then we detect the high resolution melt curve and analyze them. At last, we analyze the results of sequence and high resolution melt( HRM ). Results VEB-1 and VEB-3 gene are markedly different through HRM analysis. Conclusion It is accurately and quickly for us to identify the VEB-3 from other hypotype through the technology of HRM.

Purpose To explore the value of contrast-enhanced ultrasound(CEUS)in the differential diagnosis of gallbladder polypoid lesions(GPLs)(diameter≥10 mm).Materials and Methods A prospective enrollment of 229 patients with GPLs who underwent cholecystectomy in 17 hospitals from December 1 2021 to June 30 2024 was conducted to analyze the relationship between general data,conventional ultrasound,CEUS characteristics and the nature of GPLs.Multivariate Logistic regression was employed to identify independent risk factors for neoplastic polyps,the differential diagnostic value of different indicators was compared.Results Among 229 patients with GPLs,there were 108 cases of cholesterol polyps,102 cases of adenoma and 19 cases of gallbladder cancer.Age(Z=-4.476,P<0.001),polyp number(χ2=15.561,P<0.001),diameter(Z=-8.149,P<0.001),echogenicity(χ2=9.241,P=0.010),vascularity(χ2=23.107,P<0.001),enhancement intensity(χ2=47.610,P<0.001),enhancement pattern(χ2=6.468,P=0.011),vascular type(χ2=84.470,P<0.001),integrity of gallbladder wall(χ2=7.662,P=0.006)and stalk width(Z=-9.831,P<0.001)between cholesterol polyps and neoplastic polyps were statistically significant.Age,location,diameter,echogenicity,enhancement pattern,vascular type and stalk width between adenoma and gallbladder cancer were statistically significant(Z=-4.333,-3.902,-5.042,all P<0.05).Multivariate Logistic regression analysis showed that hyper-enhancement,branched vascular type and stalk width were independent risk factors for neoplastic polyps(OR=4.563,5.770,3.075,all P<0.001).The combination of independent risk factors was better than single factor and diameter in the differential diagnosis of cholesterol polyps and neoplastic polyps(all P<0.01).Conclusion CEUS can effectively identify the nature of GPLs and provide a valuable imaging reference for the selection of treatment methods.