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61.
上海出现PER-1型超广谱β内酰胺酶   总被引:15,自引:1,他引:15  
目的 分析多重耐药鲍曼不动杆菌148号试验菌株耐β内酰胺抗生素的原因及耐药性的转移能力。方法 用等电聚焦电泳试验和三相水解试验分析148号试验菌株所产β内酰胺酶,并进行初步分类,再用聚合酶链反应(PCR)扩增和PCR产物测序方法确认β内酰胺酶基因。结果 148号试验菌株产超广谱β内酰胺酶(ESBLs),经分子生物学方法证实有blaPER—1基因,同时还有aacA4基因。结论 148号试验菌株耐β内酰胺抗生素的原因,可能是产生了可转移的PER—1型ESBLs,blaPER—1基因位于质粒上。  相似文献   
62.

Objective

To determine the prevalence of vaginal infections and associated lifestyles of students visiting the University of Cape Coast Hospital.

Methods

Fifty female students presenting with clinical symptoms of vaginitis were sampled. One hundred samples made up of 50 urine and 50 higher vaginal swabs (HVS) were obtained from patients and questionnaire administered. Samples were wet prepared, examined microscopically, and cultured on blood and chocolate agars for 24 h at (35±2) °C. Colonial morphology, Gram reactions and biochemical tests were used for the identification of isolates.

Results

There were high percentages of pus cells (64%), epithelial cells (62%) and yeast cells (56%) in all urine samples. Bacterial isolates included Staphylococcus aureus (28%) and (22%), Klebsiella spp. (6%) and (4%) in urine and HVS samples respectively; Escherichia coli in urine (18%) and Candida in HVS (16%). The overall prevalence of vaginitis was 66%, including bacterial vaginosis 28%, Candida infection 22% and co-infection of bacterial and Candida 16%. Lifestyle data showed all sampled students were sexually active, 48% used contraceptives, 54% used antimicrobial agents, and 92% prefered wearing of trousers and shorts.

Conclusions

The present study indicates prevalence of vaginal infection among female students, which strongly correlates with student lifestyle. Education on lifestyle modifications will go a long way in reducing the prevalence of vaginitis.  相似文献   
63.
Of the three types of toxicity known so far in Portuguese shellfish, only diarrhetic shellfish poisoning (DSP) and amnesic shellfish poisoning (ASP) are produced by microalgae that seem to have been present in the last decades or centuries. The most important paralytic shellfish poisoning (PSP) producer, Gymnodinium catenatum, is hypothesised to have been introduced quite recently as only in 1976 PSP toxicity was detected for the first time in shellfish from Galicia, NW Iberian Peninsula. While ASP presents very short episodes of contamination, the concentration of DSP toxins in some years surpasses human safety values for much longer periods. It is traditionally stated that shellfish should be consumed in 'months with R' (September-April). A retrospective study of the maximum monthly DSP levels attained in mussels from a coastal lagoon-Ria de Aveiro-between 1994 and 2001, showed that the highest frequency of months with concentrations surpassing the safety level of 2 microg/g digestive glands were found in June-September, followed by May and October. These months correspond with the months of lowest historical average rainfall in the period 1941-1998.Oscillations in the rainfall pattern coincided with earliest (or latest) detection by HPLC of DSP toxins in mussel in the years studied. In a semi-closed lagunar environment prone to in situ growth of DSP-producer microalgae, like Dinophysis acuminata, rainfall affects river output, lowering salinity and disrupting water column stability that favours Dinophysis growth. The seasonality of DSP recurrence may be connected to the folk adage on safety of shellfish consumption, after many years of empirical observations by coastal populations of diarrhoea episodes in summertime.  相似文献   
64.
146株念珠菌的分布及药敏结果分析   总被引:26,自引:7,他引:26  
目的对临床送检标本分离出的念珠菌,进行细菌分布及药敏结果分析,为临床用药提供依据. 方法按常规方法转种培养,经涂片染色,发现孢子或菌丝者转种法国科玛嘉显色培养基进行分纯,用法国生物梅里埃公司VITEK-32细菌仪专用YBC卡鉴定,用ATB Fungus进行耐药监测,其中氟康唑用纸片扩散法进行监测. 结果分离出念珠菌 146株,以白色念珠菌最为多见,其次是光滑念珠菌;药敏结果敏感率由高到低为:两性霉素B 87.7%、氟康唑87.7%、5-氟胞嘧啶84.3%、制菌霉素72.6%、益康唑17.8%、咪康唑15.0%、酮康唑14.4%. 结论念珠菌感染中以白色念珠菌最为多见,药敏结果显示氟康唑、氟胞嘧啶、两性霉素B敏感性高;对送检标本及时进行真菌培养和药敏试验,合理使用抗生素和抗真菌药,减少多重耐药和深部真菌感染的发生.  相似文献   
65.
Malaria is the most prevalent vector-borne disease in the Amazon. We used malaria reports for health districts collected in 2006 by the Programa Nacional de Controle da Malária to determine whether deforestation is associated with malaria incidence in the county (município) of Mâncio Lima, Acre State, Brazil. Cumulative percent deforestation was calculated for the spatial catchment area of each health district by using 60 × 60–meter, resolution-classified imagery. Statistical associations were identified with univariate and multivariate general additive negative binomial models adjusted for spatial effects. Our cross-sectional study shows malaria incidence across health districts in 2006 is positively associated with greater changes in percentage of cumulative deforestation within respective health districts. After adjusting for access to care, health district size, and spatial trends, we show that a 4.3%, or 1 SD, change in deforestation from August 1997 through August 2000 is associated with a 48% increase of malaria incidence.  相似文献   
66.
373株不动杆菌的药物敏感性试验   总被引:1,自引:0,他引:1  
目的了解我院临床分离不动杆菌属对15种抗菌药物的耐药性,为耐药菌感染的抗菌药物选择提供依据。方法收集我院2005年7月至2006年6月所有不动杆菌临床分离株,采用琼脂稀释法测定15种抗菌药物对该菌的最低抑菌浓度。结果本研究共包括373株不动杆菌,其中鲍曼不动杆菌352株,洛菲不动杆菌21株。药敏结果显示,鲍曼不动杆菌对多黏菌素B最为敏感,细菌耐药率仅为2.6%;其次对头孢哌酮-舒巴坦、美罗培南和亚胺培南,耐药率约为15%;对左氧氟沙星、哌拉西林-三唑巴坦、头孢吡肟、氨苄西林-舒巴坦和哌拉西林的耐药率为37.5%~59.9%;对环丙沙星、阿米卡星、头孢噻肟、头孢他啶、复方磺胺甲噁唑和庆大霉素的耐药率均大于60%。与鲍曼不动杆菌相比,除多黏菌素B外,洛菲不动杆菌对上述药物的耐药率明显较低,对多数抗菌药物的耐药率在30%以下。结论不动杆菌属是医院感染的重要病原菌,耐药率高,部分菌株呈多重耐药,治疗用药应参考药敏试验结果。  相似文献   
67.
Background: Due to the failure of available antifungal agents in the treatment of candidemia and the toxic activities of these drugs, a lot of researches are being conducted to develop new nontoxic and effective antifungal agents for optimal control of fungal pathogens. The aim of this study is to evaluate the in vitro antifungal activity of propolis against yeasts isolated from the blood cultures of intensive care unit patients. Methods: Seventy‐six strains were included in this study. The in vitro antifungal activity of propolis, fluconazole (FLU), and itraconazole (ITR) was investigated by the microdilution broth methods (CLSI guidelines M27‐A3 for yeast). The propolis sample was collected from Kayseri, Turkey. Results: Of the 76 isolates, 33 were identified as Candida albicans while 37 were C. parapsilosis, three were C. tropicalis, and three were identified as C. glabrata. The geometric mean range for MIC (μg/ml) with regard to all isolates was 0.077 to 3 μg/ml for FLU and ITR, and 0.375 to 0.70 μg/ml for propolis. It was shown that propolis had significant antifungal activity against all Candida strains and the MIC range of propolis was determined as 0185 to 3 μg/ml. Conclusion: This study demonstrated that propolis had significant antifungal activity against yeasts isolated from blood culture compared with FLU and ITR. The propolis MIC in azole‐resistant strains such as C. glabrata was found lower than the FLU MIC.  相似文献   
68.
The HACEK group of bacteria – Haemophilus parainfluenzae, Aggregatibacter spp. (A. actinomycetemcomitans, A. aphrophilus, A. paraphrophilus, and A. segnis), Cardiobacterium spp. (C. hominis, C. valvarum), Eikenella corrodens, and Kingella spp. (K. kingae, K. denitrificans) – are fastidious gram-negative bacteria, part of the normal microbiota of oral and upper respiratory tract in humans. Although their pathogenicity is limited, they are responsible for 1-3% of all infective endocarditis. HACEK endocarditis mostly affect patients with underlying heart disease or prosthetic valves, and are characterized by an insidious course, with a mean diagnosis delay of 1 month (Haemophilus spp.) to 3 months (Aggregatibacter and Cardiobacterium spp.). The advent of continuously monitored blood culture systems with enriched media has erased the need for extended incubation for the diagnosis of HACEK endocarditis. Medical treatment relies on third-generation cephalosporin, with a favorable outcome in 80-90% of cases, with or without cardiac surgery.  相似文献   
69.
The study presents five fatal cases of poisoning with Taxus spp., all of which were suicides of young people aged between 16 and 26 years. Yew leaves were consumed in four fatalities, whereas a mash from Taxus was ingested in one case. No relevant concentrations of alcohol, narcotic drugs, and pharmaceuticals were determined in postmortem toxicological screening. At forensic autopsy, a widely dilated pupil was found in two decedents. Furthermore, autopsy showed unspecific findings of intoxication in all cases: acute blood congestion of lungs, liver, kidney, and brain as well as dilated cardiac ventricles. No signs of violence could be found in any of the fatalities. Yew leaves were identified in four cases in the stomach and duodenum. 3,5-Dimethoxyphenol, the aglycon of the Taxus ingredient taxicatine, was determined as toxicological evidence for the absorption of yew ingredients. Taxus intoxication could be confirmed by 3,5-dimethoxyphenol concentrations in cardiac blood between 31 and 528 ng/ml for all cases. 3,5-Dimethoxyphenol was also detected in stomach contents as well as in urine, liver, kidneys, and brain samples. Based on the different concentrations of 3,5-dimethoxyphenol determined in the cardiac blood samples, it was concluded that the form of ingestion plays a decisive role in the process of poisoning. Finally, a toxic range for Taxus poisoning based on 3,5-dimethoxyphenol as marker substance is proposed as orientation.  相似文献   
70.
From stool specimens of 118 healthy children's (1–14 years) in Portugal 92 E. coli and 101 Enterococcu s spp. strains have been isolated. Almost half (40.2%) of the E. coli isolates were resistant to ampicillin, 25.0% were resistant to tetracycline and 26.1% were resistant to streptomycin. Resistance genes detected by specific PCR included blaTEM and/or blaSHV and/or blaCTX‐M (33 of 37 ampicillin and/or cefotaxime resistant isolates), tet (A) and/or tet (B) (16 of 23 tetracycline‐resistant isolates), aad A (19 of 24 streptomycin‐resistant isolates), cml A (in the two chloramphenicol‐resistant isolates), aac (3)‐II with/without aac (3)‐IV (in the four gentamicin‐resistant isolates), sul 1 and/or sul 2 and/or sul 3 (in all trimethoprim/sulfamethoxazole resistant isolates). The majority of the resistant E. coli isolates (69.1%) belonged to phylogenetic group B2. Of the enterococci isolates E. faecium (n = 53), E. faecalis (n = 41), E. hirae (n = 4) and E. durans (n = 3) more than one‐fourth (28.7%) of the isolates were resistant to tetracycline; 21.8% were resistant to erythromycin and 8.9% were resistant to kanamycin. Resistance genes detected by PCR in enterococci included aph (3)′‐IIIa (in all kanamycin‐resistant isolates), aac (6′) (in all gentamicin‐resistant isolates), tet (M) and/or tet (L) (26 of 29 tetracycline‐resistant isolates), erm (B) (17 of 22 erythromycin‐resistant isolates). This survey showed that faecal bacteria such as E. coli and enterococci of healthy growing children's could be a reservoir of antimicrobial resistance genes. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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