ABSTRACT
Objective To induce fluconazole resistance in T.asahii by culture in medium containing increasing concentrations of fluconazole,and to evaluate the stability of the induced resistance.Methods Two T.asahii strains with a highest sensitivity to fluoconazole,including a clinical isolate CBS2479 (minumum inhibitory concentration (MIC) =0.25 μg/ml) and an environmental isolate CBS8904 (MIC =1.5 μg/ml),were selected from 11 T.asahii strains stored in the laboratory of the Department of Dermatology,General Hospital of Beijing Military Region.Both strains were respectively and serially subcultured in potato dextrose agar (PDA) medium containing growing concentrations of fluconazole (from 0.5 MIC to 256 μg/ml).E-test was performed to evaluate the susceptibility of T.asahii to fluconazole after each passage.To evaluate the stability of fluconazole resistance,the T.asahii isolates with induced resistance (MIC ＞ 256 μg/ml) were serially subcultured in drug-free PDA medium,and drug susceptibility assay was performed after each subculture.Results After serial culture in PDA medium containing fluconazole,high level of fluconazole resistance (MIC ＞ 256 μg/ml) developed in both of the fluconazole-susceptible T.asahii strains CBS2479 and CBS8904.The MIC value of fluconazole remained unchanged in the fluconazole-resistant strain CBS2479R,but gradually decreased to 64 μg/ml in the other resistant strain CBS8904R after 18-day culture in fluconazole-free PDA medium.Conclusions Fluconazole resistance can be induced in T.asahii strains from different origins by serial culture in medium containing growing concentrations of fluconazole,and the stability of the induced fluconazole resistance varies between strains of different origins.
ABSTRACT
@#目的调查定西县2—6岁精神残疾儿童患病率并探讨其危险因素。方法使用克氏孤独症行为量表(CAB),儿童孤独症评定量表(CARS量表),PEP心理教育量表等调查定西县2—6岁儿童 3776名。结果确诊精神残疾13例(男性10例、女性3例),CAB阳性率为4.76‰,患病率为3.44‰;脑器质性疾病致精神残疾者所占比例最高,为61.54%,合并智力低下者占84.62%;精神残疾的危险因素有母亲文化程度、父母婚姻状况及近亲婚配、儿童抚养人及经济收入等。结论定西县2-6岁儿童精神残疾患病率较高,家庭状况及经济收入是精神残疾形成的重要因素。