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The purpose of this study was to compare the frequency of rotator cuff pathology versus labroligamentous pathology in patients younger than 40 years and to determine whether routine MR arthrography is justified in all patients in this age group, regardless of the clinical symptoms. The MR arthrography was carried out on 332 patients 40 years of age and younger. Two hundred and forty‐three patients had clinical history of instability and possible labroligamentous pathology. Eighty‐nine patients had no history or physical signs of instability and were referred for reasons other than instability, such as assessment for rotator cuff tear. In the 243 patients younger than 40 years with clinical history of potential labral pathology, 39% (95/243) showed a labral tear and 2.1% (5/243) had a full‐thickness rotator cuff tendon tear. In the 89 patients with no history suggesting labral pathology, 19% (17/89) showed an unsuspected labral tear and 4.5% (4/89) had a full‐thickness rotator cuff tear. These findings suggest that, regardless of the clinical indication for referral, patients aged 40 and less referred for shoulder MRI should be imaged using MR arthrography because of the significant risk that symptoms are related to unsuspected labral pathology.  相似文献   
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Achieving and maintaining quality in the laboratory   总被引:1,自引:0,他引:1  
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The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
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Apical periodontitis is caused primarily by microorganisms residing in the root canals of affected teeth. Nevertheless, there is convincing evidence implicating other independent factors that adversely affect the outcome of conventional root canal therapy. In this paper, morphological evidence is presented in support of die potential role of two endogenous factors that may interfere with post-endodontic healing of the periapex. The specimens consisted of a surgical biopsy of an asymptomatic peri-apical lesion which persisted for a follow-up period of 44 months. The biopsy was processed for correlated light and electron microscopy. The lesion was characterized by the presence of a large central lumen lined by a stratified squamous epithelium. The most striking feature of the lesion was the presence of vast numbers of cholesterol crystals which congregated in the connective tissue surrounding the cyst cavity. Extensive light and electron microscopic investigation of the apical part of the root canal and the lesion foiled to reveal the presence of microorganisms. These findings strongly suggest that intrinsic factors like the accumulation of certain tissue break-down products such as cholesterol crystals, and the cystic condition of the lesion itself, can adversely affect the healing process of the periapex following root canal therapy. Consequently, such apical lesions can remain refractory to conventional endodontic therapy for long periods of time.  相似文献   
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Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
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老年胃癌患者围手术期并发症及其处理   总被引:2,自引:0,他引:2  
目的 研究老年胃癌患者的临床特点,总结老年胃癌患者的年龄、术前各种合并症等对术后并发症发生的影响.方法 总结自2005年1月至2007年1月接受手术的181例胃癌患者的临床资料,其中老年患者(年龄大于65岁者)65例,回顾性分析老年胃癌患者的年龄、术前各种合并症与术后并发症发生的关系.结果 老年胃癌组术前合并症总发生率为83%,非老年胃癌组为59%;老年胃癌组中有52%存在2种或2种以上合并症,发生率最高的合并症为高血压,达40%;老年胃癌患者的根治率为86%,非老年胃癌组的根治率为93%;老年胃癌组术后并发症的发生率为37%,术前合并高血压、糖尿病、肺部疾病、低蛋白血症、贫血者术后并发症发生率较高.结论 老年胃癌患者手术治疗后的总并发症发生率和病死率与非老年胃癌患者相比无差异.  相似文献   
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