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BACKGROUND: Blood centers are interested in understanding determinants of frequent blood donation. We hypothesized that participation in uncompensated research could result in higher donation rates. STUDY DESIGN AND METHODS: Donation rates for 2425 subjects from six US blood centers enrolled in the Retrovirus Epidemiology Donor Study‐II Donor Iron Status Evaluation Study were compared to those of nonenrolled donors (n = 202,383). Over 15 months, we compared mean donation rates and adjusted rate ratios (RRs) between enrolled and nonenrolled for three subgroups, first‐time, reactivated, and frequent donors, and donation rates before and after the study enrollment period for frequent donors only. RESULTS: Enrolled donors had higher 15‐month mean donation rates than nonenrolled donors (first‐time, 1.21 [RR = 1.91]; reactivated, 1.68 [RR = 1.83]; frequent, 3.40 [RR = 1.12]). However, frequent donors donated at approximately the same rate after enrollment as they did before enrollment in the study (3.62 per 15 months [RR = 1.12]). CONCLUSION: Donors enrolled in the study donated at a higher rate than nonenrolled donors, but frequent donors remained consistent in their donation frequency both before and after enrollment. Although increased donation rates could have been causally related to study enrollment, we cannot rule out an enrollment bias whereby more committed donors were more likely to enroll in the study.  相似文献   
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OBJECTIVE: To assess morbidity in patients with severe sepsis managed with and without drotrecogin alfa (activated). DESIGN: Analysis of secondary end points in a prospective, randomized, double-blind, placebo-controlled, multicenter, phase 3 trial (PROWESS). SETTING: A total of 164 medical institutions in 11 countries. PATIENTS: A total of 1,690 consecutive adult patients with severe sepsis. INTERVENTIONS: A 96-hr infusion of drotrecogin alfa (activated) (human recombinant activated protein C) or placebo. MEASUREMENTS AND MAIN RESULTS: Sequential Organ Failure Assessment (SOFA) scores for cardiovascular, respiratory, renal, hematologic, and hepatic organ systems were measured for 28 days. Mean cardiovascular SOFA scores were significantly lower for patients treated with drotrecogin alfa (activated) compared with placebo patients over this time period (p = .022). Drotrecogin alfa (activated)-treated patients also showed significantly faster resolution of cardiovascular (p = .009) and respiratory (p = .009) dysfunction and significantly slower onset of hematologic organ dysfunction (p = .041) compared with placebo patients for days 1 to 7. No significant differences in morbidity were observed between treatment groups among 28-day survivors. CONCLUSION: Drotrecogin alfa (activated) demonstrated significant improvements in organ function compared with placebo in a large phase 3 clinical trial that has shown a mortality benefit in patients with severe sepsis.  相似文献   
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中医药治疗绝经后骨质疏松的疗效及安全性系统评价   总被引:4,自引:1,他引:4  
目的分析中医药治疗绝经后骨质疏松症的效果和可能的不良反应.方法电子检索:MEDLINE(1966~2003)、EMBASE(1974~2003)、Cochrane Library 2003年第4期的Controlled Trials Register、Current Con-trolled Trials、The National Research Register、中国生物医学文献数据库(1978~2003)和中文科技期刊全文数据库(1977~2003)、中文学术期刊全文数据库(1994~2003),并手工检索相关领域杂志.检索截止至2003年11月.所有检索均不受语种限制.纳入以绝经后妇女为研究对象、比较中医药与其它疗法疗效的随机或半随机对照试验,评价纳入研究的质量,并用RevMan 4.2软件进行Meta分析.结果共纳入33个研究,包括2 337例患者和27种中药.部分中药或中西医结合治疗对提高患者骨密度、血清雌二醇、血清钙可能有一定疗效.例如补肾益骨膏和补肾强骨胶囊调节绝经后妇女雌激素的效果优于安慰剂,其WMD和95?分别为[0.76(0.65,0.87)]和[39.94(35.12,44.76)];其余中药因研究数较少或结论不一致尚未发现较明显的趋势.中药治疗未发现明显的副作用.结论中医药治疗绝经后骨质疏松症的疗效证据仍十分有限,尚需更多高质量研究以增加证据的强度.  相似文献   
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With recent evaluations contradicting early reports of improved outcomes from nurse-led inpatient care, the 'black box' of nurse-led care must be opened in order to examine the model of treatment. We present findings on the processes of care in one nurse-led unit (NLU), compared with an acute ward. Patterns and quality of nursing care were quantified using bar-code technology to measure type, frequency and duration of nursing activities and Quality Patient Care Scale to measure the quality of care. NLU quality matched, but did not exceed, quality on the acute ward. Patterns of care differed between wards, but activities associated with therapeutic nursing were no more frequent on the NLU. These findings support the hypothesis that disappointing outcomes in recent evaluations may be linked to failure to implement a therapeutic model of nursing.  相似文献   
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Donor‐derived fungal infections can be associated with serious complications in transplant recipients. Most cases of donor‐derived candidiasis have occurred in kidney transplant recipients in whom contaminated preservation fluid is a commonly proposed source. Donors with cryptococcal disease, including those with unrecognized cryptococcal meningoencephalitis may transmit the infection with the allograft. Active histoplasmosis or undiagnosed and presumably asymptomatic infection in the donor that had not resolved by the time of death can result in donor‐derived histoplasmosis in the recipient. Potential donors from an endemic area with either active or occult infection can also transmit coccidioidomycosis. Rare instances of aspergillosis and other mycoses, including agents of mucormycosis may also be transmitted from infected donors. Appropriate diagnostic evaluation and prompt initiation of appropriate antifungal therapy are warranted if donor‐derived fungal infections are a consideration. This document discusses the characteristics, evaluation and approach to the management of donor‐derived fungal infections in organ transplant recipients.  相似文献   
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Impact of changes in viral marker screening assays   总被引:3,自引:0,他引:3  
BACKGROUND: Monitoring the performance of routinely used infectious disease serologic tests is necessary to evaluate their effectiveness in identifying true-positive units and erroneously disqualifying safe blood donors. METHODS: With two large screening test data sets collected between 1991 and 1998 and between 1997 and 2000, the impact of changes in screening assays for HIV, HCV, and HBsAg was analyzed with regard to the prevalence of confirmed-positive, indeterminate, and confirmed-negative results and the deferral of donors with an indeterminate or negative results (donor loss). RESULTS: The prevalence of indeterminate results and donors loss increased significantly in the 6 months after introduction of an HIV-1/2 EIA. A second-generation HCV EIA increased the detection of confirmed-positive donations in repeat donors (p < 0.001) and increased the prevalence of indeterminate donations. Implementation of a third-generation HCV EIA resulted in a significant decrease in indeterminate results in first-time donors. Nonspecific test results increased when HBsAg test kits from a different manufacturer were introduced or different lots of HIV antibody screening test kits from the same manufacturer were used. CONCLUSION: Introduction of newly licensed versions of assays, switching kit manufacturers, and lot-to-lot variations have an impact on rates of deferrals of safe donors as well as sensitivity of routine screening. Before considering changes in screening tests, blood centers should be aware of, and evaluate, the potential impact on donor loss.  相似文献   
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