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101.
BackgroundExtensive and inappropriate use of quinolones has led to growing resistance rates to these broad‐spectrum antibiotics. The present study purposed to investigate the prevalence of plasmid‐mediated quinolone resistance (PMQR) genes in Klebsiella pneumoniae clinical isolates.MethodNinety‐two non‐repetitive K. pneumoniae clinical isolates were confirmed by standard microbiological methods. Antibacterial susceptibility of isolates toward seven agents from the quinolone family was evaluated by the disc diffusion method. Ciprofloxacin minimum inhibitory concentrations (MICs) were determined using the standard agar dilution method. PCR amplification was used to detect the existence of PMQR genes in the studied isolates.ResultsIn the present study, significant quinolones'' resistance (40%) was observed in K. pneumoniae isolates, and most of the strains were resistant to nalidixic acid (94.6%) and ofloxacin (45.6%). MIC analysis showed 15 strains were resistant to 6–128 μg/ml of ciprofloxacin, and five were intermediately‐resistant. PMQR genes were detected in 88% of all isolates. Acc(6’)‐Ib‐cr was constituted half of the total PMQR genes detected among ciprofloxacin non‐susceptible isolates. Of 20 ciprofloxacin non‐susceptible isolates, 65% (n = 13) harbored multiple PMQR determinants, and 15 strains were determined as integron carriage.ConclusionThe findings of this study indicated considerable resistance against quinolones, which could be correlated with the extensive and inappropriate use of this class of antibiotics as empirical treatment.  相似文献   
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Recent evidence has suggested the neuroprotective effects of physical exercise on cerebral ischemic injury. However, the role of physical exercise in cerebral ischemia-induced hippocampal damage remains controversial. The aim of the present study was to evaluate the effects of pre-ischemia treadmill training on hippocampal CA1 neuronal damage after cerebral ischemia. Male adult rats were randomly divided into control, ischemia and exercise + ischemia groups. In the exercise + ischemia group, rats were subjected to running on a treadmill in a designated time schedule(5 days per week for 4 weeks). Then rats underwent cerebral ischemia induction th rough occlusion of common carotids followed by reperfusion. At 4 days after cerebral ischemia, rat learning and memory abilities were evaluated using passive avoidance memory test and rat hippocampal neuronal damage was detected using Nissl and TUNEL staining. Pre-ischemic exercise significantly reduced the number of TUNEL-positive cells and necrotic cell death in the hippocampal CA1 region as compared to the ischemia group. Moreover, pre-ischemic exercise significantly prevented ischemia-induced memory dysfunction. Pre-ischemic exercise mighct prevent memory deficits after cerebral ischemia through rescuing hippocampal CA1 neurons from ischemia-induced degeneration.  相似文献   
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B16-F1 melanoma cells cultivated in vitro as spheroids on a non-adhesive substrate acquire in a reversible fashion an increase in lung colonization in vivo as compared to cells cultured as a monolayer. After neuraminidase treatment of protein blots, the spheroidal cells expressed an increased binding of 125I-labelled peanut lectin (PNA) to a unique glycoprotein of Mr 78,000 (gp78) which after desialylation migrated in SDS-polyacrylamide gels as an Mr 86,000 protein. Antibodies were generated against this glycoprotein purified on PNA-Sepharose and its expression on the surface of viable B16-F1 cells was demonstrated. Growth of B16-F1 melanoma cells in suspension is associated with the altered glycosylation of gp78 which may be related to the increased metastatic ability of these cells. In vitro treatment of B16-F1 cells with anti-gp78 Fab fragments prior to their injection into the tail veins of syngeneic mice resulted in a 2-fold increase in the appearance of tumor lung colonies.  相似文献   
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This research explores whether media diet influences health, not through its effects on cognition and behavior but rather through its effects on biomarkers of stress, which are implicated in a host of acute and chronic illnesses. Two hundred and forty young adults completed assessments of their media consumption habits followed at least 2 days later by measures of the stress-related hormone cortisol. Results suggest that frequency of consuming different media and genres may decrease cortisol under certain conditions and increase them under others. Further, the patterns of results were wholly different from those found for perceived stress. The implications of these findings for health-related media effects and theoretical development are discussed.  相似文献   
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A polyaniline-based composite cation-exchange material was synthesized by way of sol–gel method and studied to explore its analytical and environmental applications. It was characterized by using instrumental analyses [Fourier transform infrared (spectrometer), X-ray, thermogravimetric analysis/differential thermal analysis, standard electron microscopy, and transmission electron microscopy]. Physicochemical studies, such as ion-exchange capacity, pH titrations, and chemical stability, along with effect of eluent concentration and elution, were also performed to exploit the ion-exchange capabilities. pH titration studies showed that the material presents monofunctional strong cation-exchange behavior. This nanocomposite material is semicrystalline in nature and exhibits improved thermal and chemical stability. The partition coefficient studies of different metal ions in the material were performed in demineralised water and different surfactant media, and it was found to be selective for Pb(II) and Hg(II) ions. To exploit the usefulness of the material as an adsorbent, some important quantitative binary separations of metal ions were performed on polyaniline Zr(IV) molybdophosphate columns. This composite cation exchanger can be applied for the treatment of polluted water to remove heavy metals.  相似文献   
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Introduction. A simple endourologic technique for reconstruction of a post-traumatic obliterated urethra in a young unmarried woman is described as an alternative management to complex open urethral reconstruction.Technical Considerations. A 20-year-old woman presented with a post-traumatic obliterated urethra after a road traffic accident. The cystogram at 6 weeks did not reveal a bladder neck or urethra. The examination under anesthesia showed just a dimple at the presumed external urethral meatus. Antegrade cystoscopy revealed a complete block just distal to the bladder neck. A puncture was made from the external urethral meatus into the bladder through the bladder neck under antegrade cystoscopic guidance. The tract was dilated up to 18F using fascial dilators over a guidewire. A 16F Foley catheter was placed for 6 weeks. The operative time was 30 minutes, with no intraoperative complications. The catheter was removed at 6 weeks. Urethroscopy showed a normal urethra. She performed self-catheterization for the initial 3 months. A micturating cystourethrogram at 3 months revealed a normal urethra. She was continent and stricture free at follow-up of 16 months.Conclusion. This technique is simple and easy, with good results in selected cases of post-traumatic complete obliteration of the urethra with an intact bladder neck in young women.  相似文献   
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