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991.
992.
The current study investigated whether the androgenic activity of oral contraceptives (OC) mediates performance on sexually dimorphic cognitive tasks in 155 younger individuals. Participants were categorized by hormonal contraceptive use (user vs. nonuser) and the androgenic activity of each OC (OC generation). OC generation was determined based on previous research in which users are grouped based on the type of progestin contained in each OC. Cognitive tasks included the mental rotation task (MRT) and a recognition memory task. In addition, we examined the correlates of both menstrual cycle phase and OC use, such as mood, premenstrual syndrome, depression, blood pressure, and body fat using standardized measures. The main result was that OC androgenicity influenced MRT performance. Second generation OCs are the most androgenic. Thus, MRT performance was best in these OC users as compared to third generation users, Yasmin users and nonusers. On the other hand, Yasmin, a newer generation of OC, contains an "antiandrogenic" progestin, dropirenone. Yasmin users not only performed more poorly on the MRT in comparison to second and third generation pill users, but they performed significantly worse than OC nonusers. Results show that the androgenic activity in OCs influences MRT performance in the presence of static estrogen levels. Overall, the resulting pattern is consistent with a broad range of results demonstrating that visuospatial performance may be enhanced in women who are exposed to androgenic treatments. Furthermore, visuospatial performance is hindered with the introduction of antiandrogenic preparations.  相似文献   
993.
OBJECTIVE: Continuous venovenous hemofiltration (CVVH) is used for renal replacement and fluid management in critically ill children. A previous small study suggested that survival was associated with less percent fluid overload (%FO) in the intensive care unit (ICU) before hemofiltration. We reviewed our experience with a large series of pediatric CVVH patients to evaluate factors associated with outcome. DESIGN: Retrospective chart review. SETTING: Tertiary children's hospital. PATIENTS: CVVH pediatric ICU patients from November 1997 to January 2003. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: %FO was defined as total fluid input minus output (up to 7 days before CVVH for both hospital stay and ICU stay) divided by body weight. One hundred thirteen patients received CVVH; 69 survived (61%). Multiple organ dysfunction syndrome (MODS) was present in 103 patients; 59 survived (57%). Median patient age was 9.6 yrs (25th, 75th percentile: 2.5, 14.3). Median %FO was significantly lower in survivors vs. nonsurvivors for all patients (7.8% [2.0, 16.7] vs. 15.1% [4.9, 25.9]; p =.02] and in patients with > or =3-organ MODS (9.2% [5.1,16.7] vs. 15.5% [8.3, 28.6]; p =.01). The Pediatric Risk of Mortality Score III at CVVH initiation also was associated with survival in these groups, but by multivariate analysis, %FO was independently associated with survival in patients with > or =3-organ MODS (p =.01). CONCLUSIONS: Survival in critically ill children receiving CVVH in this large series was higher than in previous reports. CVVH survival may be associated with less %FO in patients with > or =3-organ MODS. Prospective studies are necessary to determine whether earlier use of CVVH to control fluid overload in critically ill children can improve survival.  相似文献   
994.
The severe shortage of nursing faculty in recent years has led to changes in faculty mix, with nursing programs relying on increased numbers of faculty members prepared at the master's level for coverage of nursing courses. To address the impact of these changes on faculty workload, one nursing program established a Workload Task Force to develop a workload formula that would recognize teaching, scholarship, and service contributions of all faculty members and help ensure equity in workload assignments. Details of the workload formula are offered, along with recommendations for gaining the support of faculty and ensuring transparency in implementation.  相似文献   
995.
目的:体外实验观察生物可降解材料乙交酯-丙交酯共聚物与神经生长因子复合支架的细胞相容性及其缓释作用. 方法:实验于2005-05/09在首都医科大学附属北京市神经外科研究所损伤修复实验室完成.①实验方法:乙交酯-丙交酯共聚物采用专利技术(200510011350.9)制备,体外将许旺细胞和神经干细胞与乙交酯-丙交酯共聚物共培养.②实验评估:扫描电镜下观察许旺细胞和神经干细胞在乙交酯-丙交酯共聚物内生长状况;应用组织工程技术将神经生长因子整合入乙交酯-丙交酯共聚物内,0.02 g乙交酯-丙交酯共聚物(干质量)中含有1μg神经生长因子,ELISA法检测每天神经生长因子释放的质量浓度. 结果:①扫描电镜下乙交酯-丙交酯共聚物横断面可见其为网格状,纵断面可见其直孔道.②许旺细胞和神经干细胞在乙交酯-丙交酯共聚物支架上生长良好,与其紧密贴附.③培养后第4天神经生长因子释放的质量浓度达峰值,第7天趋于平稳,稳定释放的质量浓度为100μg/L. 结论:①乙交酯-丙交酯共聚物与许旺细胞和神经干细胞具有良好的生物相容性及细胞亲和性.②按神经生长因子(1μg)与乙交酯-丙交酯共聚物(干质量0.02 g)的比例合成的神经生长因子-乙交酯-丙交酯共聚物组织工程材料可缓慢稳定释放神经生长因子,达到其可以发挥生物学活性的质量浓度100μg/L.  相似文献   
996.
The implementation of routine testing of blood donations for hepatitis B core antibody (anti-HBc) has allowed the characterization of the performance of the test in a large number of samples from apparently healthy individuals. This study reports the experience of the American Red Cross in testing 2.3 million donors for anti-HBc. The test protocol reproducibly identified a distinct population of donors. The anti-HBc-positive rate varied by region of the continental United States and by the time of year. In a case-control study, 85 percent of subsequent donations from anti-HBc-positive donors were anti-HBc positive. The predictions made in an earlier pilot study regarding the performance and impact of the test were borne out.  相似文献   
997.
Introduction: Headache is one of the most commonly reported and longest lasting symptoms that concussed athletes report, yet the etiology of headache symptoms following concussion is not entirely clear. The purpose of this study was to determine whether the e4 allele of the apolipoprotein E (APOE) gene influences the presence and severity of postconcussion headache. Method: Participants were composed of 45 concussed athletes and 43 healthy/nonconcussed athletes who were involved in a clinically based sports concussion management program. All athletes completed the Post-Concussion Symptom Scale (PCSS). The “headache” symptom from the PCSS was the primary outcome variable. Buccal samples were collected and analyzed to determine APOE genotype. Results: A significantly greater proportion of concussed e4+ athletes than e4– athletes endorsed headache. Furthermore, concussed e4+ athletes endorsed more severe headaches than e4– athletes. When examining the healthy/nonconcussed sample (i.e., athletes at baseline), results showed no differences between e4 allele groups with respect to the presence and severity of headache. Conclusions: These findings show that when compared to concussed e4– athletes, e4+ athletes are more likely to (a) endorse postconcussion headache and (b) report more severe headache symptoms following concussion. Conversely, it appears that the e4 allele does not influence baseline reports of headache. Thus, results suggest that those with the e4 genotype may be at a higher risk for experiencing headache-related difficulties only after a concussion is sustained.  相似文献   
998.
999.
1000.
Quality care for the rapidly growing number of older Americans is a major challenge facing the health care industry today. With the baby-boom generation "coming of age"--older age-the need for quality long-term care workers is on the rise. It is estimated that the number of persons needing assisted or alternative living arrangements will increase from 15 million in 2000 to 27 million in 2050 (U.S. Department of Health and Human Services [HHS], 2003). In response to the rising demand for quality long-term care workers, the Geriatric Education and Training Academy (the Academy) was created at Texas Tech University Health Sciences Center (TTUHSC) to provide advanced geriatric education and training for certified nurse aides (CNA), licensed vocational nurses (LVN) and registered nurses (RN) who work in long-term care facilities. This article describes how the Academy is addressing the need for the recruitment, education, and retention of long-term care workers for the expanding geriatric population in West Texas.  相似文献   
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