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61.
62.
The following study aimed to determine the antimicrobial susceptibility profile of Vibrio parahaemolyticus strains from fresh and frozen oysters Crassostrea rhizophorae sold in Fortaleza-Brazil. An antibiogram was performed on 87 isolates using nine antibiotics: gentamicin (Gen 10 µg), ampicillin (Amp 10 µg), penicillin G (Pen 10U), ciprofloxacin (Cip 5 µg), chloramphenicol (Chl 30 µg), nalidixic acid (Nal 30 µg), tetracycline (Tet 30 µg), vancomycin (Van 30 µg) and erythromycin (Ery 15 µg). All strains were resistant to at least one antibiotic, and 85 (97.7%) were multi-resistant, with predominance of the Van+ Pen+Amp resistance profile (n = 46). Plasmid resistance to Pen, Amp and Ery was detected. Thus, the risk that raw oyster consumption poses to the health of consumers is highlighted, due to the fact that these bivalves may host antibacterial-resistant microorganisms.  相似文献   
63.
Objective: The balance between anti-inflammatory (e.g. TGFβ) and proinflammatory cytokines (e.g. IL-1 and TNFα), regulates destructive processes in OA cartilage. IL-1 and TNFα enhance nitric oxide (NO) production in OA cartilage through the inducible nitric oxide synthase (iNOS) pathway and NO mediates many of the destructive effects of these cytokines. The aim of the present study was to investigate the effects of TGFβ on NO production in immortalized H4 chondrocytes exposed to IL-1. Results: IL-1 induced NO production in chondrocytes through nuclear factor kappa B (NF-κB) sensitive and dexamethasone insensitive expression of iNOS. TGFβ inhibited IL-1 -induced iNOS expression and NO production in chondrocytes, but it did not have any effect on iNOS mRNA levels. iNOS protein levels were similar in cells treated with IL-1 or IL-1 + TGFβ when measured after 8 h incubation, whereas when measured after 12 h and 24 h incubations, iNOS protein levels were 50% and 80% lower in cells treated with IL-1 + TGFβ than in cells treated with IL-1 alone. Conclusion: TGFβ suppressed IL-1-induced iNOS expression and NO production in chondrocytes, probably by enhancing iNOS protein degradation. This finding suggests an additional mechanism for TGFβ to counteract the destructive effects of IL-1 in OA. Received 24 March 2005; returned for revision 16 June 2005; accepted by J. Hamilton 7 July 2005  相似文献   
64.
Before heart rate variability can be used as an investigational tool in the clinical setting, its reproducibility must be known. We studied heart rate variability four times during 44 weeks in 15 hypertensive patients with sleep apnoea syndrome. Time and frequency domain analytical approaches were used during the spontaneous and controlled breathing tests, orthostatic manoeuvre and the cold pressor test. Alterations in resting heart rate were taken into account using the coefficient of component variance. In general, the response of heart rate variability was abnormal and variability was reduced in the hypertensive patients with sleep apnoea syndrome compared with reference data. Time domain measures of heart rate variability demonstrated generally better reproducibility over four recordings than frequency domain measures in these hypertensive patients with sleep apnoea syndrome. On the other hand, the reproducibility of frequency domain measures depended on the specific conditions: during orthostatic manoeuvre and cold pressor test the best reproducibility was found using normalized units. In the reference data set, there were no significant differences between the two heart rate variability recordings during any of the autonomic nervous function tests. In this follow-up study we found that simple procedures such as the controlled breathing test show good reproducibility. More complex tests such as the orthostatic manoeuvre require special attention in order to obtain acceptable reproducibility of heart rate variability measurements. Quantitatively minor changes in the variability indices when the overall variability is reduced exert major effects on the results. Therefore we suggest that reproducibility data obtained in healthy volunteers are not valid for the interpretation of data in patients with damaged cardiovascular autonomic control.  相似文献   
65.
H Bauchner  SI Pelton  JO Klein 《Pediatrics》1999,103(2):395-401
BACKGROUND: Emergence of resistant bacterial pathogens has increased concerns about antibiotic prescribing patterns. Parent expectations and pressure may influence these patterns. OBJECTIVE: To understand how parents influence the prescribing patterns of physicians and what strategies physicians believe are important if we are going to reduce inappropriate use of oral antimicrobial agents. DESIGNS AND METHODS: One thousand pediatricians who are members of the American Academy of Pediatrics were asked to complete a semi-structured questionnaire. The physicians were chosen randomly by the American Academy of Pediatrics. RESULTS: Nine hundred fifteen pediatricians were eligible and 610 surveys were analyzable, for a response rate of 67%. The majority of respondents were male (56%), worked in a group practice (51%), saw an average of 114 patients per week and were in practice for 14 years. Forty percent of the pediatricians indicated that 10 or more times in the past month a parent had requested an antibiotic when the physician did not feel it was indicated. Forty-eight percent reported that parents always, most of the time, or often pressure them to prescribe antibiotics when their children are ill but antibiotics are not indicated. In follow-up questions, approximately one-third of physicians reported they occasionally or more frequently comply with these requests. Seventy-eight percent felt that educating parents would be the single most important program for reducing inappropriate oral antibiotic use and 54% indicated that parental pressure, in contrast to concerns about legal liability (12%) or need to be efficient in practice (19%), contributed most to inappropriate use of oral antibiotics. CONCLUSIONS: Pediatricians acknowledge prescribing antimicrobial agents when they are not indicated. Pediatricians believe educating parents is necessary to promote the judicious use of antimicrobial agents.  相似文献   
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67.
ObjectiveTo explore the prevalence, pathogenicity, and antibiotic susceptibility patterns of urinary tract infections at the University of Port Harcourt Teaching Hospital.MethodsSamples from 400 patients with a presumptive diagnosis of urinary tract infection including 250 non pregnant females and 150 males were used for this study. They were distributed into two groups: children aged 2 to 17 (Group A) and adults aged 18 to 75 (Group B). The standard wire loop and agar diffusion technique were employed for culture and susceptibility testing, respectively. Data obtained were analysed using SPSS, version 14.Results30.0% of Group A and 41.0% of Group B had significant bacteriuria with 66.7% and 79.3% as females, respectively. The commonest isolates cultured were Escherichia coli (32.8%), Staphylococcus aureus (17.2%), and Klebsiella spp. (16.4%). About 76.6% of isolates were sensitive to the fluorinated quinolones, 31.2% to the aminoglycosides, and 22.7% to the urinary antiseptic, nitrofurantoin. The isolates were non-sensitive to tetracycline (93.8%), cotrimoxazole (92.2%), and nalidixic acid (86.7%). Most isolates showed non-uniform sensitivity patterns to the cephaloporins (cefuroxime and ceftazidime). Pseudomonas spp. isolates were generally resistant to the fluorinated quinolones.ConclusionThough the fluorinated quinolones are still largely effective for empirical therapy in urinary tract infections, the importance of prior sensitivity testing in checking the emergence of bacterial antibiotic resistance can not be overemphasized.  相似文献   
68.
The effects of local hyperthermia treatment on contact sensitivity (CS) and on the number of Langerhans cells (LCs) were studied in mice. CS was significantly suppressed when mice were sensitized in the hyperthermia treated skin I, 2 or 4 days after treatment (43 degrees C for 45 min). This suppressive effect was not observed 7 or 14 days after the treatment. CS was also suppressed when mice were sensitized in non-treated skin I day after the treatment. The density of LCs detected as ATPase-positive cells also decreased significantly 1, 2, 4 and 7 days after the treatment. There appeared to be a positive correlation between the number of LCs and the extent of CS when mice were sensitized at hyperthermia treated skin. It was observed that this suppressive effect on CS was dose- and temperature-dependent. It could be transferred by spleen cells from the hyperthermia treated and DNFB-sensitized donors, and was antigen specific when spleen cells were transferred before sensitization of the recipient mice. This indicated it was, in part, associated with the induction of suppressor cells. These findings suggest that local hyperthermia treatment reduces the number of LCs with subsequent suppression of the induction phase of delayed-type hypersensitivity by the generation of antigen-specific suppressor cells.  相似文献   
69.

Background

Meconium aspiration-induced hypertensive lung injury is frequently associated with neuronal damage. Inhaled nitric oxide (iNO) is widely used in the treatment of pulmonary hypertension, but its effects on the brain are poorly known.

Aims

The aim of this study was to determine the effects of iNO treatment on the neuronal tissue after meconium aspiration.

Study design

71 anesthetized, catheterized and ventilated newborn piglets were studied for 6 h. Thirty-five piglets were instilled with a bolus of human meconium intratracheally and 36 piglets with saline instillation served as controls. Nineteen meconium piglets and 17 control piglets were continuously treated with 20 ppm of iNO, started at 30 min after the insult. The extent of neuronal injury was analysed histologically, and the levels of brain tissue lipid peroxidation products, reduced glutathione (GSH), myeloperoxidase activity and oxidized DNA were analysed as indicators of oxidative stress.

Results

iNO treatment diminished the pulmonary hypertensive response caused by meconium aspiration, but did not change systemic or carotid hemodynamics. NO administration was associated with reduced neuronal injury and diminished amount of oxidized DNA in the hippocampus of the meconium piglets. Further, iNO treatment was associated with decreased level of GSH in the cortex, but no change in lipid peroxidation production or myeloperoxidase activity was detected in any of the studied brain areas.

Conclusions

Our results suggest that iNO treatment may inhibit DNA oxidation and neuronal injury in the hippocampus, associated with newborn meconium aspiration.  相似文献   
70.
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