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91.
ObjectiveTo determine the prevalence of asymptomatic bacteriuria in pregnancy, to consider the antimicrobial sensitivity patterns of involved uropathogens, to elucidate the safety profiles of antibacterial agents, and to evaluate the role of urinalysis in screening for asymptomatic bacteriuria.MethodsAbout 760 apparently healthy pregnant subjects attending the Antenatal Clinic of the University of Port Harcourt Teaching Hospital were randomly selected for this study. Urinalysis and microscopy, culture, and sensitivity tests were carried out on clean-catch midstream urine samples obtained from subjects. Biochemical reagent strips were used for urinalysis while the standard wire loop and agar diffusion technique were respectively employed for culture and susceptibility testing.ResultsA total of 111 samples yielded moderate or severe growth on culture after 48 hours comprising 35, 31, 27, and 18 isolates of Staphylococcus spp., Proteus spp., Klebsiella spp., and Escherichia spp, respectivehy. Urinalysis results were positive for the presence of nitrate reductase and leucocyte esterase activity in 17 urine samples of these 111 samples. The isolates showed a general sensitivity to the fluorinated quinolones and to Nitrofurantoin.ConclusionsThe prevalence of asymptomatic bacteriuria is 14.6%, with the predominant organism being Staphylococcus spp. Drugs used for treatment should have excellent fetal safety profiles, and a rapid screening test with a high negative predictive value for asymptomatic bacteriuria would be ideal.  相似文献   
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Background: Several studies have shown a reduction in enamel bond strengths when the bonding procedure is carried out immediately after vital bleaching with peroxides. This reduction in bond strengths has become a concern in cosmetic dentistry with the introduction of new “in‐office” and “waiting‐room” bleaching techniques. The aim of this in vitro study was to evaluate the effect of three bleaching regimens: 35% hydrogen peroxide (HP), 35% carbamide peroxide (CP), and 10% CP, on dentin bond strengths. Materials and Methods: One hundred and twenty fresh bovine incisors were used in this study. The labial surface of each tooth was ground flat to expose dentin and was subsequently polished with 600‐grit wet silicon carbide paper. The remaining dentin thickness was monitored and kept at an average of 2 mm. The teeth were randomly assigned to four bleaching regimens (n = 30): (A) control, no bleaching treatment; (B) 35% HP for 30 minutes; (C) 35% CP for 30 minutes; and (D) 10% CP for 6 hours. For each group, half of the specimens (n = 15) were bonded with Single Bond/Z100 immediately after the bleaching treatment, whereas the other half was bonded after the specimens were stored for 1 week in artificial saliva at 37°C. The specimens were fractured in shear using an Instron machine. Results: For the groups bonded immediately after bleaching, one‐way analysis of variance (ANOVA) followed by the Duncan's post hoc test revealed a statistically significant reduction in bond strengths in a range from 71% to 76%. For the groups bonded at 1 week, one‐way ANOVA showed that group B (35% HP for 30 min) resulted in the highest bond strengths, whereas 10% CP resulted in the lowest bond strengths. Student's t‐test showed that delayed bonding resulted in a significant increase in bond strengths for groups B (35% HP) and C (35% CP); whereas the group bleached with 10% CP (group D) remained in the same range obtained for immediate bonding. Storage in artificial saliva also affected the control group, reducing its bond strengths to 53% of the original.  相似文献   
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Background

We sought to determine the prevalence of echocardiographically determined left ventricular systolic dysfunction in asymptomatic hypertensive subjects seen in Abeokuta, Nigeria.

Methods

Echocardiography was performed in 832 consecutive hypertensive subjects referred for cardiac evaluation over a three-year period.

Results

Data were obtained in 832 subjects (50.1% women) aged 56.0 ± 12.7 years (men 56.9 ± 13.3 years, women 55.0 ± 12.0 years, range 15–88). The prevalence of left ventricular systolic dysfunction (LVSD) was 18.1% in the study population (mild LVSD = 9.6%, moderate LVSD = 3.7% and severe LVSD = 4.8%). In a multivariate analysis, male gender, body mass index and LV mass were the predictors of LVSD.

Conclusion

Significant numbers of hypertensive subjects in this study had varying degrees of left ventricular systolic dysfunction. Early introduction of disease-modifying drugs in these patients, such as angiotensin converting enzyme inhibitors or angiotensin receptor blockers may retard or prevent the progression to overt heart failure.  相似文献   
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Social intervention against AIDS among injecting drug users   总被引:1,自引:1,他引:1  
Many drug injectors continue to engage in behaviors that lead them to become infected with HIV in spite of a wide variety of public health programs. In addition, many persons have begun to inject drugs in spite of knowing the risks of AIDS. The inadequacy of current efforts to prevent these behaviors suggests that additional forms of intervention should be attempted. We suggest that social interventions be tried to complement current programs (almost all of which have an individual focus). Evidence that social factors such as peer pressure and the social relations of race affect risk behavior is presented. Social interventions that are discussed include organizing drug injectors against AIDS in ways analogous to those in which gays organized against the epidemic, and finding ways to change large-scale social relationships that predispose people to inject drugs.  相似文献   
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Grandparents are a vital link for young families. The support grandparents can provide to the new family is now more important than ever. A creative grandparenting program can increase the likelihood that grandparent support is effective and welcomed. This article includes a discussion of such a program, suggested content areas to include, and the development of appropriate teaching strategies.  相似文献   
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