Objective To establish a gas chromatograph method for determing Chloroform, ethyl acetate and N, N-dimethyl formamide in butoconazole nitrate. Methods The samples was detected by Headspace Gas Chromatography. Temperature programming method was adpoted and FID was used as detector. The injector temperature was 200 ℃, and the detector temperature was reach 250 ℃. Nitrogen was used as carrier gas in the experiment. Results In the mentioned chromatographic conditions, Chloroform, ethyl acetate and N, N-dimethyl formamide had good linear relationships in the ranges of 0. 066-0. 588,0. 062-0. 556 and 0. 896-8. 061 μg·mL-1 respectively. The average recoveries were 99. 18%,102. 84% and 98. 71%. RSD were 3. 87%,4. 33% and 3. 71%. Conclusion The detection method is sensitive, accurate, reliable, and can be used as a quality control for butoconazole nitrate.

Objective:To establish a method for the determination of dichloromethane, methanol and ethanol in fenticonazole ni-trate. Methods:The samples were detected by headspace GC. The column was OV-1301(30 m × 0. 53 mm,3. 0 μm), the detector was FID with nitrogen as the carrier gas, the detector temperature was 250 ℃ and the injector temperature was 200 ℃. Results:The linear range of dichloromethane, methanol and ethanol was 2. 436-21. 924(r=0. 998 8), 12. 268-110. 412(r=0. 999 5) and 20. 052-180. 468 μg·ml-1(r=0. 996 9) with the average recovery of 99. 30% (RSD=2. 36%), 100. 21%(RSD=1. 07%) and 100. 15%(RSD=1. 21%)(n=9), respectively. Conclusion:The detection method is sensitive, accurate and reliable, and can be used in the quality control of fenticonazole nitrate.

Objective:To compare the efficacy of domestic and imported hemostatic clips in preventing delayed post-polypectomy bleeding (DPPB) after endoscopic resection of colorectal polyps ≥ 10 mm.Methods:Clinical data of 789 patients who underwent endoscopic resection of colorectal polyps (polyp diameter ≥10 mm) in Beijing Friendship Hospital, Capital Medical University from January 2018 to December 2019 were collected. The patients were divided into DPPB group ( n=15) and non-DPPB group ( n=774). Univariate and multivariate logistic regression models were used to analyze the influential factors for DPPB. The patients using one type of hemostatic clip were divided into the domestic hemostatic clip group ( n=499) and the imported hemostatic clip group ( n=208). The efficacy of hemostatic clips in preventing DPPB in the two groups was compared. Results:Among the 789 patients undergoing endoscopic resection of colorectal polyps, 1.9% (15/789) suffered from DPPB. Multivariate logistic regression analysis showed that pedunculated polyp was an independent risk factor for DPPB ( OR=6.621, 95% CI: 2.278-19.241, P=0.001), and closure of mucosal defect was an independent protective factor for DPPB ( OR=0.169,95% CI: 0.050-0.570, P=0.004). Regardless of physician experience, there was no significant difference between the domestic and imported hemostatic clip group in preventing DPPB after endoscopic resection of colorectal polyps ≥10 mm [experienced physicians: 1.8% (7/385) VS 0.6% (1/175), χ2=1.314, P=0.445; common physicians: 2.6% (3/114) VS 3.0% (1/33), χ2=0.010, P>0.999]. The domestic hemostatic clip group paid for less medical expenses than the imported hemostatic clip group (experienced physicians: 1 433.51±889.02 yuan VS 3 033.97±1 686.87 yuan, t<0.001 , P<0.001; common physicians: 1 181.58±815.29 yuan VS 3 303.46±1 690.43 yuan, t<0.001 ,P<0.001). Conclusion:Pedunculated polyp is an independent risk factor for DPPB after endoscopic resection of colorectal polyp larger than 10 mm, and clipping can significantly reduce the risk for DPPB. There is no significant difference in the prevention of DPPB between domestic and imported clips, but domestic clips compared with imported clips yield less medical burden, which are suitable for promotion to primary hospitals and major clinical centers.

Aim To investigate the role of cholesterol in the regulation of lipid raft and the function of platelets.Methods Using in vitro incubation of methyl β-cyclodextrin(MβCD)and in vivo elevation of peripheral blood total cho-lesterol levels to remove and load platelet cholesterol,respectively.Cholera toxin B staining combined with flow cytometry was used to detect platelet lipid raft content,fluorescence antibody staining combined with flow cytometry was used to detect the expression levels of P-selectin and activated integrin α Ⅱ bβ3,annexin Ⅴ labeling combined with flow cytometry was used to detect the level of phospholipid efflux,in vitro experimental system and rat tail bleeding experiment were used to detect platelet aggregation ability.Results The content of lipid raft on B lymphocytes decreased with the removal of cholesterol,while in vitro incubation of MβCD to remove platelet cholesterol significantly increased its lipid raft level(P＜0.05).Consistent with this,in vivo cholesterol loading increased the lipid raft content of B lymphocytes but decreased the lipid raft content of platelets(P＜0.05).The increase in lipid raft after removing cholesterol was not conducive to platelet activation and aggregation function.In vivo cholesterol loading downregulated platelet lipid raft content(P＜0.05),enhanced its ability to respond to low concentration stimulant for activation aggregation and coagulation,and this enhancing effect disappeared after cholesterol removal.Conclusion Platelet cholesterol is a key regulator of platelet lipid raft content and platelet function,which can negatively regulate lipid raft,promote platelet activation,and enhance their coagulation function.