[The correlation between expression level of femB and resistance phenotype of methicillin-resistant Staphylococcus aureus (MRSA)].

Objective: To investigate the correlation between the phenotype and expression level of femB of Staphylococcus aureus (MRSA), to discuss the mechanism of different phenotypes in methicillin-resistant Staphylococcus aureus.

Methods: The minimal inhibitory concentrations (MICs) of oxacillin against 71 clinical isolates of Staphylococcus aureus were determined by agar dilution method according to NCCLS. The production of beta-lactamase was identified by Cefinase paper strip method.

[Effects of chelation therapy with succimer in young rabbits of moderate lead poisoning].

Objective: To explore the effect of chelation therapy with succimer (DMSA) in male rabbits of moderate lead poisoning during juvenile stage.

Methods: Twenty-four 45-day-old male New Zealand rabbits were randomly divided into three groups (therapy group, TG; positive control group, PG and negative control group, NG, n=8). The TG and PG were orally exposed to lead acetate (5 mg x kg(-1) x d(-1)) for 6 weeks.

[Association of genotype of OXA-carbapenemases of Acinetobacter baumannii and antibiotic resistance].

Objective: To determine the association of the antibiotic resistance of clinical isolates of Acinetobacter baumannii and the genotype of OXA-carbapenemases.

Methods: One hundred and twenty Acinetobacter baumannii strains were isolated from clinical specimens in the West China Hospital from January 2005 to June 2006. The MICs of 12 common antimicrobial agents were determined by 2-fold agar dilution method followed by NCCLS recommendations.

[Effects of moderate lead poisoning on the hippocampus tissue of rabbits in juvenile stage].

Objective: To understand the effects of moderate lead poisoning on the hippocampus tissue of rabbits in juvenile stage.

Methods: Sixteen 45-day-old male New Zealand rabbits were randomly divided into blank group and lead-exposed group,8 for each group. Rabbits in the lead-exposed group were treated with 5 mg x kg(-1) x d(-1) lead acetate in their forage for 6 weeks to establish a moderate lead poisoning animal model.

[Study on the correlation between resistance phenotype and expression level of femA of Staphylococcus aureus].

Objective: To detect the expression level of femA of Staphylococcus aureus strains with different phenotype.

Methods: 15 strains of the non-beta-lactamase-producing clinical isolates with different phenotype by agar dilution and by nitrocephin paper strip method were chosen as the object of test, in addition to 4 donative strains (BB270, BB308, BB586, COL). Total RNA were extracted and analysed by agarose gel electrophoresis.

[A study on the mechanism of drug resistance in Staphylococcus aureus].

Objective: To inquire into the mechanism of drug resistance in Staphylococcus aureus.

Methods: A total of 198 strains of Staphylococcus aureus were isolated from the samples sent to the Clinical Laboratory of Microbiology,West China Hospital. The resistance of Staphylococcus aureus to Methicillin was assayed with agar dilution.

[Surveillance on antibiotic resistance of Stenotrophomonas maltophilia in Chengdu and Chongqing area].

Objective: To survey the antibiotic resistance of Stenotrophomonas maltophilia in Chengdu and Chongqing area and guide the rational antibiotics usage in the treatment of Stenotrophomonas maltophilia infection.

Methods: Minimal inhibitory concentrations (MICs) of 9 antibiotics against Stenotrophomonas maltophilia were measured using two-fold agar dilution method.

Results: A total of 154 strains of Stenotrophomonas maltophilia are multi-drug resistant.