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OBJECTIVES: The purpose of this study was to examine the in-hospital outcome and influence of glycoprotein (GP) IIb/IIIa antagonists on patients with acute coronary syndromes (ACS) across a range of renal function. BACKGROUND: Recent studies demonstrate increasing cardiovascular risk with progressive renal dysfunction. Previous studies investigating GP IIb/IIIa antagonist use have excluded patients with renal dysfunction. METHODS: Patients presenting with ACS between January 1999 and May 2000 were identified, and data on demographics, in-hospital management, and clinical events were collected using standardized definitions. Patients were stratified according to renal function assessed by calculated creatinine clearance (CrCl) at presentation. Primary outcome measures included in-hospital mortality and major bleeding events. RESULTS: Renal insufficiency was present in 312 of 889 patients. There were 40 in-hospital deaths. In non-dialysis-dependent patients, as CrCl worsened, there was a decline in utilization of routine diagnostics and therapeutics, an increase in in-hospital mortality (p = 0.002), and an increase in major bleeding (p = 0.03). Although the use of GP IIb/IIIa antagonists was associated with an increase in major bleeding (p < 0.001), there was a protective effect on in-hospital mortality (p = 0.04) after controlling for CrCl. CONCLUSIONS: Renal dysfunction is present in a substantial proportion of patients with ACS and is associated with increased in-hospital death. Although GP IIb/IIIa antagonist use in patients with ACS and renal insufficiency resulted in increased bleeding events, its administration was associated with a decreased risk of in-hospital mortality. These preliminary findings need to be confirmed in future randomized clinical trials.  相似文献   
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Because the acquisition of sexually transmitted infections (STIs) is based on individual sexual behaviors, the most successful STI prevention initiatives have been behavioral interventions seeking to change individual risk behaviors. This article explores systematic and community-based prevention initiatives and the steps in development and validation of behavioral interventions to reduce STIs. Key interventions and the trials in which they were proven effective are discussed in detail. It is hoped that a greater understanding of the development and validation of behavioral interventions for STI prevention will encourage physicians to accept these interventions as additional tools to prevent disease and suffering.  相似文献   
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Biases in avian sex ratios have been documented in relation to a variety of social and environmental conditions. Previous studies suggest that treatment with hormones can stimulate females to manipulate offspring sex, and that this effect occurs before ovulation. For example, acute and chronic treatments with testosterone stimulated significant skews towards male offspring. Hormones may act by influencing which sex chromosome is donated by the heterogametic female bird into the oocyte. However, it is difficult to pinpoint when effects of testosterone on offspring sex occurred in previous experiments because testosterone treatments were given either chronically over the entire period of follicular development or many hours before the critical period of chromosome segregation. We injected laying hens with testosterone injections 5 h prior to ovulation to target this critical period and quantified the sexes of the subsequently ovulated eggs. We hypothesized that an injection of testosterone coincident with segregation of sex chromosomes would stimulate hens to produce more male than female offspring. As hypothesized, hens injected with testosterone produced a significant bias towards male offspring compared to controls, nearly 70%. These results suggest that acute testosterone elevation during meiotic segregation may mediate skews in avian primary sex ratios.  相似文献   
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Tenofovir (TFV) 1% vaginal gel has been found to decrease sexual transmission of human immunodeficiency virus. To initiate investigations during pregnancy, 16 healthy pregnant women scheduled for cesarean delivery received a single application of TFV gel preoperatively. Maternal serum drug concentrations were determined and fetal cord blood, amniotic fluid, placental tissue, and endometrial tissue specimens were collected. The median maternal peak concentration and cord blood TFV concentrations were 4.3 and 1.9 ng/mL, respectively (~100- and 40-fold lower than after TFV oral dosing, respectively). No adverse events were related to the use of TFV gel. These findings support ongoing and future investigations of TFV gel in pregnancy. CLINICAL TRIAL REGISTRATION: NCT00572273. http://www.clinicaltrials.gov/ct2/show/NCT00540605?term=mtn-002&rank=1.  相似文献   
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