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991.
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目的 探讨结肠气钡双重造影和结肠CT在结直肠疾病诊断中的应用价值,并对比分析两种检查方法的优缺点.方法 回顾性分析2005年6月至2013年8月我院213例结肠气钡双重造影和结肠CT检查结果,对比观察两种检查方法所检出的病种、结直肠肿瘤和息肉的大小、部位及并发症发生情况.结果 结肠气钡双重造影对溃疡性结肠炎、慢性阑尾炎、憩室等疾病和近端结肠及小病灶的诊断能力优于结肠CT;结肠CT对结直肠肿瘤及远端结肠的诊断能力则优于结肠气钡双重造影.结论 结肠气钡双重造影和结肠CT各具优势,在临床工作中应视具体情况加以选择或联合应用. 相似文献
993.
Antonio Gigante Alberto Busilacchi Barbara Lonzi Stefano Cecconi Sandra Manzotti Chiara Renghini Alessandra Giuliani Monica Mattioli‐Belmonte 《Journal of orthopaedic research》2013,31(5):738-745
Injured tendons have limited repair ability after full‐thickness lesions. Tendon regeneration properties and adverse reactions were assessed ex vivo in an experimental animal model using a new collagen I membrane. The multilamellar membrane obtained from purified equine Achilles tendon is characterized by oriented collagen I fibers and has been shown to sustain cell growth and orientation in vitro. The central third of the patellar tendon (PT) of 10 New Zealand White rabbits was sectioned and grafted with the collagen membrane; the contralateral PT was cut longitudinally (sham‐operated controls). Animals were euthanized 1 or 6 months after surgery, and tendons were subjected to histological and Synchrotron Radiation‐based Computed Microtomography (SRµCT) examination and 3D structure analysis. Histological and SRµCT findings showed satisfactory graft integration with native tendon. Histological examination also showed ongoing angiogenesis. Adverse side‐effects (inflammation, rejection, calcification) were not observed. The multilamellar collagen I membrane can be considered as an effective tool for tendon defect repair and tendon augmentation. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 738–745, 2013 相似文献
994.
Laura Evangelista Andrea Guttilla Fabio Zattoni Pier Carlo Muzzio Filiberto Zattoni 《European urology》2013
Context
Determination of tumour involvement of regional lymph nodes in patients with prostate cancer (PCa) is of key importance for the proper planning of treatment.Objectives
To provide a critical overview of published reports and to perform a meta-analysis about the diagnostic performance of 18F-choline and 11C-choline positron emission tomography (PET) or PET/computed tomography (CT) in the lymph node staging of PCa.Evidence acquisition
A Medline, Web of Knowledge, and Google Scholar search was carried out to select English-language articles published before January 2012 that discussed the diagnostic performance of choline PET to individualise lymph node disease at initial staging in PCa patients. Articles were included only if absolute numbers of true-positive, true-negative, false-positive, and false-negative test results were available or derivable from the text and focused on lymph node metastases. Reviews, clinical reports, and editorial articles were excluded. All complete studies were reviewed; thus qualitative and quantitative analyses were performed.Evidence synthesis
From the year 2000 to January 2012, we found 18 complete articles that critically evaluated the role of choline PET and PCa at initial staging. The meta-analysis was carried out and consisted of 10 selected studies with a total of 441 patients. The meta-analysis provided the following results: pooled sensitivity 49.2% (95% confidence interval [CI], 39.9–58.4) and pooled specificity 95% (95% CI, 92–97.1). The area under the curve was 0.9446 (p < 0.05). The heterogeneity ranged between 22.7% and 78.4%. The diagnostic odds ratio was 18.999 (95% CI, 7.109–50.773).Conclusions
Choline PET and PET/CT provide low sensitivity in the detection of lymph node metastases prior to surgery in PCa patients. A high specificity has been reported from the overall studies. Studies carried out on a larger scale with a homogeneous patient population together with the evaluation of cost effectiveness are warranted. 相似文献995.
目的 建立一个满足临床和科研要求的可视化的多来源多精度的颅颌面三维数字化模型.方法 采用锥体束断层CT(CBCT)扫描整个头部,利用不同组织的亨氏单位(Houns Field值)的不同,提取出面部软组织、颌面部骨骼以及牙列3种组织结构,利用三维重建的方法,重构出面部、颌骨和牙齿三部分的数字化三维模型,同时采用激光扫描的方法获得带有纹理信息的面部三维模型以及高精度三维数字化牙列模型,利用三维图形学中的配准技术,将激光扫描获得的面部、三维模型转化到CT来源的重建的三维颅颌面数字化模型所在坐标系.结果 获得一个带有颜色信息的面部软组织、高精度牙列和清晰骨骼的复合三维数字化颅颌面模型.结论 多来源的三维数字化颅颌面模型是一种能够达到临床和科研要求的高精度数字化模型. 相似文献
996.
John A. Shepherd Sanford Baim John P. Bilezikian John T. Schousboe 《Journal of clinical densitometry》2013,16(4):489-495
There have been many scientific advances in measurement of fat and lean body mass as determined by dual-energy X-ray absorptiometry (DXA). The International Society for Clinical Densitometry (ISCD) convened a Position Development Conference (PDC) on the use of DXA for body composition measurement. Previously, no guidelines to the use of DXA for body composition existed. The recommendations pertain to clinically relevant issues regarding DXA indications of use, acquisition, analysis, quality control, interpretation, and reporting were addressed. The topics and questions for consideration were developed by the ISCD Board of Directors and the Scientific Advisory Committee and were designed to address the needs of clinical practitioners. Three Task Forces were created and assigned these questions and asked to conduct comprehensive literature reviews. The Task Forces included participants from 6 countries and a variety of interests including academic institutions, private clinics, and industry. Reports with proposed Position Statements were then presented to an international panel of experts with backgrounds in DXA and bone densitometry and a variety of fields that use body composition measures. The PDC was held in Tampa, FL, contemporaneously with the Annual Meeting of the ISCD, March 21 through March 23, 2013. This report describes the methodology of the 2013 ISCD Body Composition PDC and summarizes the results. Three separate articles in this issue will detail the rationale, discussion, and additional research topics for each question the Task Forces addressed. 相似文献
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