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81.
Current medical procedures used in prenatal screening and diagnosis of handicapping conditions are reviewed. These strategies include ultrasound, amniocentesis, chorionic villus biopsy, restriction enzyme analysis, maternal serum analysis, fetoscopy, and fetal serum analysis. Along with an explanation of each method, advantages, disadvantages, and risks involved with each are provided. An understanding of these procedures by medical and educational personnel is encouraged, and the potential benefits of prenatal identification of handicapping conditions are emphasized.  相似文献   
82.
目的:探讨良恶性肝外胆管梗阻病变的CT表现及其诊断意义。方法:回顾经手术病理证实的肝外胆管梗阻病变76例(良性34例,恶性42例)。结果:肝内胆管呈枯枝状轻中度扩张,肝内外胆管不一致扩张(内轻外重),肝外胆管远段梗阻,梗阻部胆管呈削尖状狭窄,肝外胆管壁呈弥漫环形增厚,对良性梗阻的诊断有重要意义。肝内胆管呈软藤状重度扩张,肝外胆管中段梗阻,梗阻部胆管呈伴或不伴肿块的截断型或突然狭窄型,肝外胆管壁局限不规则增厚,高度揭示恶性梗阻。结论:良恶性肝外胆管梗阻病变均有特征性CT表现,通过分析胆管形态和临床资料基本能判断梗阻的性质。  相似文献   
83.
脾脏钝伤的CT诊断   总被引:2,自引:1,他引:1  
本文回顾性分析了32例脾脏钝伤CT平扫的表现;对脾损伤进行CT分类;指出腹腔积血和脾周血块(“哨兵血块征”)在诊断脾损伤方面的作用。CT平扫诊断钝性脾脏损伤是一种敏感、可靠的方法,可帮助外科医生制订治疗方案。CT平扫诊断钝性脾损伤的灵敏度为94%,诊断正确率为91%  相似文献   
84.
目的 探讨结石性肠梗阻的诊断及治疗。方法 比较腹部平片和B超的术前诊断率。随访患者以了解不同手术方法的得失。结果 腹部平片术前诊断率为22%,辅以B超则上升为66%。4例Ⅰ期手术和3例Ⅱ期手术患者无死亡。无胆管炎发作。结论 仅靠腹部平片易漏诊,辅以B超则能提高术前诊断率。争取回期手术切除胆囊、闭合胆肠瘘,如有困难,则动员患者6-8周后Ⅱ期手术。  相似文献   
85.
Abstract Perioscan requires a plaque sample to detect the presence of enzymes capable of degrading N-benzoyl-DL-arginine-2-naphthylamide (BANA) from relatively few anaerobic periodontal pathogens. Periocheck assays the presence of neutral proteases in crevicular fluid. The aim of this study was to compare these test kits with traditional clinical methods of detecting periodontal disease and to monitor the ability of the kits to reflect the response to initial therapy. 19 patients with moderately severe chronic periodontitis were seen before and after a course of oral hygiene and root instrumentation consisting of 4 appointments. Clinical measurements and test assays were collected at 5 diseased sites and 2 healthy sites in each subject. Complete data from 125 sites were available for statistical analysis. At baseline Periocheck had a sensitivity of 88% and a specificity of 61% whereas Perioscan had a sensitivity of 99% and a specificity of 55%, when related to the clinical diagnosis. A composite clinical assessment, based on improvement or deterioration of one whole unit change of the subjective clinical indices and 2mm changes or greater in probing depth or probing attachment level, revealed 75 sites which improved following treatment, whereas 45 sites did not change and 5 sites deteriorated. The probability that the tests agreed with the clinical outcome after treatment, was calculated as 50.4% for Periocheck and 52% for Perioscan. The diagnostic kits did not reliably reflect the clinical assessment of periodontal disease in the cross sectional study, or the outcome following treatment.  相似文献   
86.
The objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X-ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians in their daily practice.  相似文献   
87.
对60例临床疑为头痛型痛痫的患者进行24h脑电监测。结果表明:24h脑电监测对痛痫特殊类型的检出率明显高于常规EEG。在14例(23.3%)有痫样放电的患者中,出现痫样放电以睡眠期多于清醒期;且睡眠周期中以NREMⅠ,Ⅱ期最常见。对6例(16.2%)反复阵发出现高波幅额中线θ节律而无痫性放电的患者亦应考虑头痛型癫痫的诊断。  相似文献   
88.
A critical incident study in child health   总被引:3,自引:0,他引:3  
The critical incident technique is an objective method of analysing doctors' professional behaviour. It extracts the skills which should be taught and assessed in any training programme. In such a study in child health, 438 incidents were collected from general practitioners, paediatricians and others, and analysed according to the problem, the disease, the setting, the skill and the attitude involved. Most of the problems concerned non-specific symptoms (e.g. 'unwell baby', 'fever') and the main skill categories (each with many subheadings) were clinical management (especially at home), the diagnostic process and interpersonal skills. Training of doctors in child health should emphasize the competencies highlighted in this study.  相似文献   
89.
The efficacy of radiology in evaluating dysphagia was studied in 86 patients by comparison to endoscopic findings. In the 66 patients with endoscopic abnormalities radiology was correct in 54, for a sensitivity of 82%. Sensitivity of radiology improved to 95% if mild esophagitis was excluded. In the 20 patients with normal endoscopy, radiology was normal in 18 (90%). Thus radiology proved to be a reliable means of evaluating the esophagus in patients with dysphagia.  相似文献   
90.
原发性甲状腺功能亢进症合并甲状腺癌18例分析   总被引:1,自引:0,他引:1  
目的:探讨原发性甲状腺功能亢进症(甲亢)合并甲状腺癌(甲癌)的诊断和治疗。方法:回顾分析1990年1月于2000年1月手术治疗18例甲亢合并甲癌患者的临床资料,结果:微小癌占83%(15/18)。术前彩超检查15例,14例发现可疑结节;13例行癌侧叶全切除和对侧叶次全切除术,5例行双侧叶次全切除术,其中3例同时行颈淋巴结清扫术,1例二次行颈淋巴结清扫术。随访16例,平均随访7年,1例死于癌肺转移,余者仍存活,结论:术前常规彩超检查发现可疑结节有助于术中冰冻切片病理检查,手术治疗应兼顾甲亢和甲癌。  相似文献   
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