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971.
Phenomenon: Peer learning has many benefits and can assist students in gaining the educational skills required in future years when they become teachers themselves. Peer learning may be particularly useful in clinical learning environments, where students report feeling marginalized, overwhelmed, and unsupported. Educational interventions often fail in the workplace environment, as they are often conceived in the “ideal” rather than the complex, messy real world. This work sought to explore barriers and facilitators to implementing peer learning activities in a clinical curriculum. Approach: Previous peer learning research results and a matrix of empirically derived peer learning activities were presented to local clinical education experts to generate discussion around the realities of implementing such activities. Potential barriers and limitations of and strategies for implementing peer learning in clinical education were the focus of the individual interviews. Findings: Thematic analysis of the data identified three key considerations for real-world implementation of peer learning: culture, epistemic authority, and the primacy of patient-centered care. Strategies for peer learning implementation were also developed from themes within the data, focusing on developing a culture of safety in which peer learning could be undertaken, engaging both educators and students, and establishing expectations for the use of peer learning. Insights: This study identified considerations and strategies for the implementation of peer learning activities, which took into account both educator and student roles. Reported challenges were reflective of those identified within the literature. The resultant framework may aid others in anticipating implementation challenges. Further work is required to test the framework's application in other contexts and its effect on learner outcomes.  相似文献   
972.
Job satisfaction ranks highly as one of the main factors influencing turnover rates among nurses. Mental health nursing has been reported to be a particularly stressful specialty, yet little is known about the level of job satisfaction among psychiatric nurses in Singapore. Resilience is defined as a means of adapting to stress at the workplace, and could serve as a factor influencing job satisfaction. The present study aimed to explore the current level of job satisfaction among psychiatric nurses working in the only tertiary psychiatric institution in Singapore, the influencing factors, and the relationship between resilience and job satisfaction. A survey questionnaire consisting of the following was administered to all eligible nurses working in the Institute of Mental Health between the period of 16–24 December 2014: (i) The McCloskey and Mueller Satisfaction Scale; (ii) The Resilience Scale; and (iii) sociodemographic data form. A total of 874 nurses were eligible for participation in the study, and a total of 748 nurses responded, totalling 85.6% response. A mean satisfaction score of 95.21 and mean resilience score of 125.74 were obtained. Mean satisfaction and resilience scores were the highest for nurses with longer working experience and those of older age. A positive and significant association between satisfaction and resilience scores (= 0.001) was obtained. Psychiatric nurses in Singapore are generally satisfied with their job, but this can be further improved with the strengthening of personal resilience.  相似文献   
973.
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   
974.
Introduction: Conduction abnormalities after transcatheter aortic valve replacement (TAVR) account for a high percentage of post-TAVR complications.

Areas covered: The etiology of conduction abnormalities is closely tied to cardiac anatomy (length of membranous septum, degree of calcification, location of left bundle within the membranous septum), baseline conduction abnormalities (preprocedure right bundle branch block), and procedural variables (type of valve, depth of implant). Management of new high-grade AV block and new left bundle branch block varies by institution in the absence of consensus guidelines.

Expert opinion: Authors describe the incidence, etiology, outcomes, and management of conduction abnormalities related to aortic stenosis and TAVR.  相似文献   

975.
976.
AIMS: Malignant ventricular arrhythmias can arise in a subset of congestive heart failure (CHF) patients after they undergo cardiac resynchronization therapy (CRT), thus counteracting the haemodynamic benefits typically associated with biventricular pacing. This study seeks to assess whether alteration of the ventricular transmural repolarization and conduction due to reversal of the depolarization sequence during epicardial or biventricular pacing facilitate the development of ventricular arrhythmias. METHODS AND RESULTS: ECGs and monophasic action potential (MAP) were recorded during programmed stimulation from right ventricle (RV) endocardium (RV-Endo), left ventricle (LV) epicardium (LV-Epi), or both (biventricular, Bi-V) in 15 individuals without structural heart diseases. In patients with severe CHF and CRT (n=21), ECGs were collected during RV-Endo, LV-Epi, and Bi-V pacing. MAP duration on intracardiac electrogram, the QT, JT, and T(peak)-T(end) intervals on ECGs at different pacing sites were measured and compared. In subjects with or without structural heart disease, compared with RV-Endo pacing, LV-Epi and Bi-V pacing resulted in a longer JT (341.78+/-61.97 ms with LV-Epi, 325.86+/-59.69 ms with Bi-V vs. 286.14+/-38.68 ms with RV-Endo in CHF individuals, P<0.0001) or T(peak)-T(end) interval (121.55+/-19.88 ms with LV-Epi, 117.71+/-42.63 ms with Bi-V vs. 102.28+/-12.62 ms with RV-Endo in normal-heart subjects, P<0.0001; 199.70+/-62.44 ms with LV-Epi, 184.89+/-74.08 ms with Bi-V vs. 146.41+/-31.06 ms with RV-Endo in CHF patients, P<0.0001), in addition to prolonged myocardial repolarization time and delayed endocardial activation. During follow-up, sudden death and arrhythmia storm occurred in two CHF patients after CRT. CONCLUSION: Epicardial and biventricular pacing prolong the time and increase the dispersion of myocardial repolarization and delay the transmural conduction. All of these should be considered as potential arrhythmogenic factors in CHF patients who receive CRT.  相似文献   
977.
A 68-year-old man was admitted with arthralgia in both knees. Chest CT showed a tumor 4cm in diameter with a cavity in the right lung. Clinical stage IV (T2N3M1) lung adenocarcinoma was diagnosed. The thickness of the fibular cortex was shown on the radiograph and distal symmetric accumulation of extremities was shown using bone scintigraphy. These results suggested that the knee-joint pain was caused by Marie-Bamberger syndrome. After chemotherapy with cisplatin plus gemcitabine, the tumor decreased, and the bone pain disappeared. This is a case that showed the correlation between tumor reduction and bone pain in Marie-Bamberger syndrome.  相似文献   
978.
979.
The effect of pancreatic endocrine tissue allotransplantation on the development of peripheral nerve dysfunction in streptozotocin induced diabetic rat recipients across major histocompatibility barrier was evaluated. Motor nerve conduction velocity (MNCV) and evoked muscle potential amplitudes (EMPA) were used to assess nerve function. Of the 49 transplanted diabetic animals, 40 had permanent functional allograft of either intraportal pancreatic whole islets (PWI) or intracerebral pancreatic endocrine cells (PEC). Normal MNCV and EMPA values (47.65 +/- 2.03; 5.22 +/- 0.43) were found among the recipients of intracerebral transplantation of PEC. The MNCV and EMPA were 43.30 +/- 2.59 and 4.49 +/- 0.53 respectively, in recipient rats with successful intraportal whole islet transplant. The nine animals with rejected whole islet allografts yielded MNCV and EMPA values (38.90 +/- 2.73; 3.87 +/- 0.59) comparable to the diabetic control rats.  相似文献   
980.
The present study was performed to evaluate the potential role and functional interaction of angiotensin II AT1 and AT2 receptors (AT1R and AT2R) in the regulation of blood pressure and glucose homeostasis in fructose-induced insulin-resistant, hypertensive rats. Male Sprague-Dawley rats on fructose-enriched or regular diets for 4 weeks were subjected to 2-step euglycemic euinsulinemic (EEI) and euglycemic hyperinsulinemic (EHI) clamp studies with [3-3H]glucose infusion. After a 40-minute basal period, selective AT1R and AT2R antagonists, losartan (LOS, 10 mg/kg IV bolus) and PD123319 (PD, 50 microg/kg/min), alone or in combination were separately given to control and fructose-fed groups in the 2 clamp periods. The results showed that during the EEI period, LOS significantly reduced the elevated blood pressure in fructose-fed rats, whereas PD further increased fructose-induced high blood pressure. Coadministration of LOS and PD did not alter the elevated blood pressure in fructose-fed rats. Administration of LOS and/or PD failed to change the blood pressure in control rats. During the EHI period, blockade of both AT1R and AT2R eliminated the insulin-induced blood pressure elevation in control and fructose-fed rats. Hepatic glucose production (HGP) did not alter among groups in the basal and EEI periods. Insulin infusion (EHI period) markedly suppressed HGP in control rats, but this suppressive effect was significantly attenuated in fructose-fed rats. LOS administration further reduced the insulin-induced suppression of HGP in fructose-fed rats. The whole-body glucose uptakes (rates of glucose disappearance, Rd) during the basal and EEI periods were similar among groups. During the EHI period, Rd was markedly increased in all groups and the magnitude of increase was significantly greater in control rats than in fructose-fed rats except those with LOS treatment. LOS treatment also redirected Rd in favor of glycolysis in fructose rats, but not in control rats, during the EEI and EHI periods. The effects of LOS on glycolysis during the 2 clamp periods and on HGP during the EHI period were reversed when PD was concomitantly administered, but PD alone did not alter glucose metabolism throughout the experiment in fructose-fed rats. Administration of LOS and/or PD did not change the glucose metabolism in control rats. Our data suggest that AT2R can counterbalance the AT1R-mediated effects on blood pressure and glucose metabolism in fructose-induced insulin-resistant, hypertensive rats. Furthermore, AT1R- and AT2R-mediated effects on blood pressure are disassociated with their actions on glucose metabolism in this hypertensive model.  相似文献   
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