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ObjectivesIn May 2012, United States Preventive Services Task Force (USPSTF) finalized its recommendation against prostate-specific antigen (PSA) screening in all men. We aimed to assess trends in PSA screening frequency amongst primary care physicians (PCPs) surrounding the May 2012 USPSTF recommendation.Methods and materialsThe electronic data warehouse was used to identify men aged between 40 and 79 years with no history of prostate cancer or urology visit who were evaluated by an internal medicine or family practice physician between 2007 and 2012. Analyses were directed toward PSA testing within 6-month time period from June to November, with particular focus on the 2011 (pre-USPSTF recommendation) and 2012 (post-USPSTF recommendation) cohorts. The primary outcome measure was proportion of men with at least 1 PSA test during the 6-month pre- and post-USPSTF recommendation periods.ResultsA total of 112,221 men met inclusion criteria. There was a significant decrease in screening frequency between the 2011 and 2012 cohorts (8.6% vs. 7.6%, P = 0.0001; adjusted odds ratio 0.89, 95% confidence interval 0.83–0.95). This decrease was most evident amongst patients aged 40 to 49 years (5.6% vs. 4.6%, P = 0.004) and 70 to 79 years (7.9% vs. 6.2%, P = 0.01). A significant decrease was also observed in patients with highest previous PSA value<1.0 (P<0.0001) and 1.0 to 2.49 ng/ml (P = 0.0074).ConclusionsSince the USPSTF recommendation was finalized, there is evidence of continuing decreases in PSA testing by PCPs. PCPs may be shifting toward more selective screening practices, as decreases in screening are most pronounced in the youngest and oldest patients and in those with history of PSA values<2.5 ng/ml.  相似文献   
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Maternally administered recombinant human granulocyte colony- stimulating factor (rhG-CSF) has been shown to cross the placenta and induce a peripheral neutrophilia and increases in the marrow and spleen neutrophil storage pools in fetal and newborn rats. In the present study, we have used this model system to investigate the efficacy of prenatally administered rhG-CSF on neonatal defense to a lethal challenge with Group B-beta hemolytic Streptococcus (GBS). Pregnant rats were injected with rhG-CSF twice daily beginning 6 days before parturition. At birth, all pups were infected with a dose of GBS that is lethal for 90% of infected pups (LD90). Survival was monitored daily for 5 days. Survival of infected pups from saline-treated mothers beyond 60 hours after infection was 10%. No difference in survival was observed among pups from mothers treated 2 and 4 days before parturition. In contrast, we determined that survival was 82.5% among infected pups from mothers treated for 6 days before parturition with rhG-CSF. Our results demonstrate that maternal administration of rhG- CSF augments neonatal defenses against a lethal bacterial challenge.  相似文献   
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Isosorbide dinitrate is an effective vasodilator that improves resting left ventricular performance in patients with congestive heart failure, but little is known of the effect of the drug on the response to exercise. Bicycle exercise to symptomatic maximum was performed by 18 patients with class II to IV congestive heart failure before and 90 minutes after administration of isosorbide dinitrate, 40 mg orally. Although resting pulmonary wedge pressure and systemic vascular resistance were significantly reduced after isosorbide dinitrate, exercise duration was not altered and maximal oxygen consumption was not significantly changed (13.6 +/- 1.3 [SEM] standard error of the mean versus 13.8 +/- 1.2 ml/kg per min). At peak exercise pulmonary wedge pressure of 37.1 +/- 1.7 mm Hg, cardiac index of 4.19 +/- 0.35 liters/min per m2, and systemic vascular resistance of 14.7 +/- 1.3 units were not significantly different after nitrate administration. However, at submaximal loads, pulmonary wedge pressure was reduced from 33.6 +/- 1.7 to 27.9 +/- 1.8 mm Hg (P less than 0.01), and systemic resistance from 16.5 +/- 1.5 to 13.7 +/- 1.0 units (P less than 0.01) after administration of isosorbide dinitrate. Thus, short-term administration of nitrates does not improve maximal exercise capacity or left ventricular performance at maximal exercise in patients with congestive heart failure, but it does appear to improve pump function at submaximal work loads and may therefore enable patients to perform limited exercise more comfortably.  相似文献   
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Ventricular dysfunction in coronary artery disease   总被引:2,自引:0,他引:2  
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