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Background The development of evidence based guidelines is a demanding and time consuming process. Therefore it is important to share the knowledge and discuss the structure of these guidelines in detail. Objectives To present a method report on the development process of the European evidence based guidelines on the systemic treatment of psoriasis vulgaris with the aim to offer guidance to other guidelines groups with lesser experience and to critically appraise the methodology of the guidelines development process. Methods The guidelines are based on the previously evaluated literature from three European national evidence based guidelines and an additional systematic search and evaluation of new literature. Further steps included a structured consensus conference and a DELPHI procedure to develop the recommendations, as well as several internal and external reviews. All steps were coordinated by the Division of evidence based medicine in cooperation with a group of methodologists. Results A total of 114 studies were included, serving as base for the efficacy chapters of the intervention. The recommendations, based on the efficacy and the level of evidence of the included studies were discussed and finally consented by the guidelines group. After subsequent reviews the guidelines were presented to the European Dermatology Forum, European Academy of Dermatology and Venereology and Union Européenne des Médicins Spécialistes for approval and published in October 2009. Conclusion The development of European evidence based guidelines requires a coordinated structure which can be achieved by the integration of an experienced group of methodologists. Nevertheless further improvements are imaginable and might be considered for an update or other European evidence based guidelines.  相似文献   
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AIM: The aim of the present in-vitro study was to combine directly the Canal Leader handpiece (SET, Olching, Germany) with the electronic apex locators ROOT ZX (Morita, Kyoto, Japan) and JUSTY (Yoshida, Tokyo, Japan) to find out whether the working length values thus obtained were identical to those resulting from the combination of the same electronic devices with hand files. METHODOLOGY: A total of 50 natural extracted teeth with single canals and mature apices were used. A radiograph was used as a control and the distance from the radiographic apex to the tip of the file was measured and compared with the results of the electronic length determination. RESULTS: For both electronic devices the differences amongst the distribution of the measurements were not statistically significant under the specified conditions (P > 0.05), indicating that the measurements with hand files and with the Canal Leader were identical for the majority of the cases. CONCLUSIONS: Under the conditions of this study the working length of canals obtained with electronically assisted hand files were similar to those obtained with the electronically assisted mechanical handpiece Canal Leader.  相似文献   
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自国产沉香(Aquilaria sinensis)[瑞香科(Thymeleaceae)植物]的挥发油中,经硅胶柱层析和离心薄层层析分离得到一新的倍半萜,命名为异白木香醇(isobaimuxinol),根据光谱(IR,1HNMR,13CNMR,2 D-NMR和MS)分析确定其结构式为(Ⅰ)所示,并用X-光衍射晶体解析进一步确定了其立体化学。同时,也从该植物挥发油的低沸点部分分离得到四个已知化合物:苄基丙酮,对甲氧基苄基丙酮,茴香酸和β-沉香呋喃。这些化合物均为首次从该植物中得到。  相似文献   
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ABSTRACT— Glafenine was associated with hepatic injury in 38 cases. The causal relationship was assessed on the basis of the temporal relationship with drug use, course and exclusion of other causes. In 27 cases a causal relationship was considered likely, i.e. ‘probable’ (12 cases) or ‘possible’ (15 cases), whereas in 11 cases it was either unlikely or unclassifiable. In both the ‘probable’ and ‘possible’ groups 60–70% of individuals were women. Jaundice was present in three-quarters of cases in both groups. Eosinophilia was more frequent in the group of ‘probable’ cases, and this group had the highest case-fatality rate (42%). Onset varied from 2 days (after a rechallenge) to 8 months, but most cases appeared between 2 weeks and 4 months after starting therapy. Histology in 22 cases showed a predominantly hepatocellular pattern, varying from spotty panlobular necrosis, centrilobular and (sub)massive necrosis (acute pattern) to fibrosis and cirrhosis (chronic pattern). The chemical structure of glafenine and the clinicopathological pattern it induces resemble that of cinchophen. The incidence is unknown. Either metabolic idiosyncrasy or an immunoallergic mechanism seems to be responsible.  相似文献   
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Background and Aim:  The aim of the present study was to investigate the clinical effectiveness, safety, and outcome associated with the use of covered expandable Nitinol stents (Taewoong Medical, Seoul, Korea) for the treatment of malignant gastroduodenal obstructions.
Methods:  Between March 2001 and October 2004, covered expandable Nitinol stents were placed in 68 consecutive patients under endoscopic and fluoroscopic guidance for the following reasons: gastric carcinoma ( n  = 49), recurrent carcinoma after partial gastrectomy ( n  = 7), or another malignant neoplasm involving the duodenum ( n  = 12).
Results:  Technical success was achieved in 60 of the 68 patients (88.2%). After stent placement, mean dysphagia score improved from a mean of 3.5 to 1.2 ( P  < 0.001). The mean period of primary stent patency was 107.2 days. During follow up (mean 4.4 months; range, 1–15 months), major complications (migration [6], bleeding [3], perforation [1], ingrowth [1], overgrowth [7], fistula [1]) occurred in 19 patients (27.9%), and stent migration occurred in six (8.8%) (proximal migration into the stomach [ n  = 3], or distal migration [ n  = 3]). Recurrent dysphagia (mainly due to tumor ingrowth/overgrowth) occurred in eight patients (11.8%).
Conclusion:  Covered expandable Nitinol stents appear to offer an effective and feasible palliative therapy in patients with a malignant gastroduodenal obstruction.  相似文献   
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