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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3.
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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G Trautmann J L Gutmann M E Nunn D E Witherspoon J D Shulman 《Quintessence international, dental digest》2000,31(10):713-718
OBJECTIVE: The purpose of this study was to identify the pulpal findings encountered by practitioners when accessing complete-coverage crowns that require nonsurgical root canal treatment and the relevance of coronal leakage to the success of the RTC. METHOD AND MATERIALS: The survey package consisted of a cover letter stating the instructions, rationale, and purpose for the questionnaire, a questionnaire with 8 short-answer questions, and a stamped, self-addressed envelope. A randomized sample of active dentists (300 general practitioners, 300 prosthodontists, and 300 endodontists) was selected. Collected data were analyzed with the chi-square test. RESULTS: A 60% response rate was obtained. Statistically significant differences were found among the practitioner groups, depending on the question. General practitioners and endodontists obtain access through crowns and maintain these crowns as final restoration significantly more often than do prosthodontists. Practitioners responded that teeth with complete crowns require nonsurgical root canal treatment after 5 to 10 years. CONCLUSION: Respondents believe that leakage must be addressed when endodontic access cavities in artificial crowns are restored after nonsurgical root canal treatment. General practitioners perform nonsurgical root canal treatment more frequently than do prosthodontists. Practitioners indicated that when teeth with complete crowns require nonsurgical root canal treatment, treatment is most often performed 5 to 10 years after placement of the crown. 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