Dl-tetrahydropalmatine (THP) 5 ~ 15 mg ? kg-1 iv markedly reduced the incidences of cardiac arrhythmias and myocardial lipidperoxide content after reperfusion of the is-chemic myocardium in rats. In isolated rat ventricular muscles, THP 1,3 and 10 ?mol?L-1 shifted the concentration-effect curves for phenylephrine to the right unparally, together with decreasing their maximal responses,exhibiting a non-competed antagonistic action. It was also found that THP 10 ?mol?L-1was able to reduce the amplitude of delayed afterdepolar-izations and to stop triggered activity and/or ab-normal automatic activity induced by reoxygena-tion of hypoxic myocardium in isolated ventricular muscles of guinea pig. These results suggest that the protective effects of THP might be attributed, at least in part, to the depression of delayed afterdepolarizations and the prevention of oxygen free radical injury without the involvement of the cardiac ?1-adrenoceptors.

Objective To investigate the application of hepatitis C virus RNA and antibody detection method in population screening.Methods The colloidal gold rapid test method and the enzyme-linked immunosorbent assay (ELISA)were adopted to detect hepatitis C virus (HCV)antibodies,and the real-time quantitative PCR (RT-PCR)was adopted to detect HCV-RNA viral load.Results (1)Among 539 samples,266 cases were antibody negative and 263 cases were antibody positive.(2)Among 67 cases in the HCV-RNA viral load <103 IU/mL group,60 cases were HCV antibody positive by ELISA and 30 cases were HCV antibody positive by colloidal gold rapid test.Among 208 cases in the HCV-RNA viral load ≥ 103 IU/mL,199 cases were antibody positive by ELISA,but only 181cases were antibody positive by the colloidal gold rapid method.Other 6 cases of were 2 kinds of antibody negative had the HCV-RNA viral load ≥ 103 IU/mL.(3)208 cases of HCV-RNA viral load ≥ 103 IU/mL sample were divided in-to four groups.GGT,ALT and AST were statistically significantly different P <0.05),while ALB and S/CO values hadno statisti-cal difference (P >0.05).Conclusion In order to reduce the missed diagnosis rate and diagnose hepatitis C as early as possible,the above laboratory detection methods should be jointly applied and the comprehensive analysis should be conducted in population screening.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.