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1.
V Aerra M Kuduvalli AN Moloto AK Srinivasan AD Grayson BM Fabri AY Oo 《Journal of cardiothoracic surgery》2006,1(1):6-5
Background
Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery. 相似文献2.
目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Copper is believed to be hepatotoxic in Indian Childhood Cirrhosis and Wilson's disease. However, copper-loading causes only minimal hepatic damage in animal models. The hypothesis was therefore proposed that a second hepatic insult may precipitate or perpetuate liver injury in a copper-laden liver. In non-copper-dosed rats CCl4 (10 mmol/kg, i.p.) produced elevated serum AST (809 +/- 298 IU/l, normal 20 +/- 5) and ALT (295 +/- 157 IU/l, normal 6 +/- 1) and extensive liver cell necrosis, portal tract inflammation, fat deposition, and perilobular hepatocyte ballooning. In rats whose liver copper was elevated from 75 +/- 13 to 461 +/- 13 micrograms/g by oral copper supplementation, CCl4 produced much smaller increases in AST (492 +/- 80 IU/l) and ALT (172 +/- 57 IU/l) and mild focal liver cell necrosis. Fat deposition and perilobular vacuolation were not reduced. Prior copper-loading of rats unequivocally protected against the CCl4-induced liver injury. Triglyceride accumulation, however, was apparently unaffected. The possible interactions of copper with prostaglandin-mediated inflammation and with free-radical-induced liver damage are discussed. 相似文献
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Context Residents in all disciplines serve as clinical teachers for medical students. Since the 1970s, there has been increasing evidence to demonstrate that residents wish to teach and that they respond positively to formal teacher training. Effective resident‐as‐teacher (RaT) programmes have resulted in improved resident teaching skills. Current evidence, however, is not clear about the specific features of an effective RaT programme. Objectives This study was performed in order to investigate the effectiveness of RaT programmes on resident teaching abilities and to identify the features that ensure success. Methods of assessment used to ascertain the effectiveness of RaT programmes are also explored. Methods The literature search covered the period between 1971 and 2008. Articles focusing on improving resident teaching skills were included. Each study was reviewed by two reviewers and data were collected using a standard abstraction summary sheet. Study outcomes were graded according to a modified Kirkpatrick's model of educational outcomes. Results Twenty‐nine studies met review inclusion criteria. Interventions included workshops, seminars, lectures and teaching retreats. Twenty‐six studies used a pre‐ and post‐intervention outcome comparison method. Subjective outcome measures included resident self‐evaluation of teaching skills or evaluation by medical students, peers and faculty members. Objective outcome measures included written tests, evaluation of teaching performance by independent raters and utilisation of objective structured teaching examinations. One study objectively measured learning outcomes at the level of medical students, utilising the results of an objective structured clinical examination. Overall resident satisfaction with RaT programmes was high. Participants reported positive changes in attitudes towards teaching. Participant knowledge of educational principles improved. Study methodologies allowed for significant risks of bias. Conclusions More rigorous study designs and the use of objective outcome measures are needed to ascertain the true effectiveness of RaT programmes. Future research should focus on determining the impact of RaT programmes on learning achievement at the level of medical students. 相似文献
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The efficacy of intranasal interferon alpha-2a in respiratory syncytial virus infection in volunteers 总被引:1,自引:0,他引:1
In a double-blind, placebo-controlled study, self-administered intranasal interferon alpha-2a or placebo was given both before and after challenge with respiratory syncytial virus. The incidence of colds and the severity of signs and symptoms were reduced in those receiving interferon alpha-2a as compared with those given placebo. In a further double-blind, placebo-controlled study, self-administered interferon alpha-2a or placebo was given only to those volunteers who developed colds following challenge with respiratory syncytial virus. There was no evidence that interferon alpha-2a reduced the severity of the signs and symptoms or shortened the duration of the illness. The similarity of these results to the effect of interferon alpha-2a in rhinovirus infections in volunteers is discussed. 相似文献
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R Zachariah AD Harries MP Spielmann V Arendt D Nchingula R Mwenda O Courtielle P Kirpach B Mwale FML Salaniponi 《Malawi medical journal : the journal of Medical Association of Malawi》2002,14(2):10-12
In Thyolo district, Malawi, an operational research study is being conducted on the efficacy and feasibility of co-trimoxazole prophylaxis in preventing deaths in HIV-positive patients with tuberculosis (TB). A series of cross-sectional studies were carried out to determine i) whether faecal Escherichia coli (E.coli) resistance to co-trimoxazole in TB patients changed with time and ii) whether the resistance pattern was different in HIV positive TB patients who were taking co-trimoxazole prophylaxis. Co-trimoxazole resistance among E.coli isolates in TB patients at the time of registration was 60% in 1999 and 77% in 2001 (p<0.01). Resistance was 89% among HIV-infected TB patients (receiving co-trimoxazole), while in HIV negative patients (receiving anti-TB therapy alone) it was 62% (p<0.001). The study shows a significant increase of E.coli resistance to co-trimoxazole in TB patients which is particularly prominent in HIV infected patients on co-trimoxazole prophylaxis. Since a high degree of plasmid-mediated transfer of resistance exists between E.coli and the Salmonella species, these findings could herald limitations on the short and long term benefits to be anticipated from the use of co-trimoxazole prophylaxis in preventing non-typhoidal salmonella bacteraemia and enteritis in HIV infected TB patients in Malawi. 相似文献
10.
From 240 questionnaires, we investigated the prevalence of stress fractures in competitive collegiate female long distance runners and its relationship to menstrual history. The runners were divided into three groups according to their menstrual history: very irregular 69/240 (0 to 5 menses/year), irregular 51/240 (6 to 9 menses/year), and regular 120/240 (10 to 13 menses/year). Stress fractures occurred in 49% of the very irregular runners, 39% of the irregular runners, and 29% of the regular runners. The majority of the stress fractures occurred in the tibia. Runners who had never used oral contraceptives were over twice as likely to have had a stress fracture when compared with runners who had used oral contraceptives for more than 1 year. These data suggest that female distance runners who have a history of irregular or absent menses and who have never used oral contraceptives may be at an increased risk for developing a stress fracture. When amenorrheal runners were separated from the very irregular group, an alarming trend was noted in eating behavior disorders. Forty-seven percent of the amenorrheal group, 20% of the one to five menses/year group, 10% of the irregular group, and 7% of the regular group admitted to an eating behavior disorder. 相似文献