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61.
795例肺癌术后发生心律失常的多因素分析   总被引:1,自引:0,他引:1  
目的探讨肺癌术后发生心律失常的危险因素及其防治。方法回顾分析2002年1月~2004年1月我院肺癌手术795例,其中全肺切除术176例,肺叶切除术509例,楔型切除术110例。术后发生心律失常273例,应用Logistic回归对影响术后发生心律失常可能的危险因素进行分析。结果本组病例心律失常总发生率为34.3%(273/795),多因素Logistic逐步回归分析显示高龄、吸烟史、心律失常史、全肺切除、术中心包损伤、术后肺不张是术后心律失常的主要危险因素(P〈0.05),术后镇痛是保护因素(P=0.017)。结论心脏的储备功能降低、对手术损伤及缺氧的耐受力降低是导致术后心律失常的原因,采取一些预防措施可以减少其发生率。  相似文献   
62.
垂体腺瘤是发生于垂体前叶的良性肿瘤,约占中枢神经系统肿瘤的10%-20%,而无功能微腺瘤占到成人尸检的23%左右。生理上根据免疫组化将垂体腺瘤按功能分为有激素分泌活性腺瘤(functioning pituitary adenoma,FPA)和非激素分泌活性腺瘤(non—functioning pituitary adenoma,NFPA)两大类。[第一段]  相似文献   
63.
膀胱癌中环氧化酶-2的表达与临床病理的关系(英文)   总被引:4,自引:2,他引:2  
目的 探讨环氧化酶 - 2 (COX - 2 )表达与膀胱癌生物学行为的关系及其意义。方法 采用免疫组化SABC法检测 5 4例膀胱癌、2 9例癌旁组织和 10例正常膀胱粘膜中的COX - 2表达 ,结合临床病理资料进行分析。结果 COX - 2在不同膀胱组织中的表达差异有显著性 (P <0 .0 5 ) ,即膀胱癌组织 >癌旁组织 >正常膀胱粘膜。COX - 2表达随膀胱癌病理级和临床分期的增加而增加 (P <0 .0 5、P <0 .0 1) ,且癌组织中COX - 2表达与淋巴转移有关 (P <0 .0 5 )。结论 COX - 2表达与膀胱癌病理分级、临床分期、淋巴转移有关 ,提示它可能在胱癌的发生、发展中扮演重要角色 ,通过抑制COX - 2活性可能为膀胱癌的防治提供新途径。  相似文献   
64.
选用长白猪8只于麻醉下开胸,于在体猪心上探讨心肌缺血时冠脉仍保留有部分扩张储备,而未被充分利用的机理。实验结果表明:降低左冠状动脉前降支(LAD)内压至4.67kPa时,由LAD分别输入腺苷、山莨菪碱、生理盐水(2ml/min),皆能诱发出明显的LAD流量增加(P<0.05)。在维持LAD内压不变,并持续分别输入上述三种溶液的同时,从LAD远端取血测血液流变学指标,结果显示,输入生理盐水和山莨菪碱使红细胞压积降低,血浆粘度和全血粘度下降;心肌缺血时,冠脉内输注药物所诱发出的“冠脉扩张储备”部分是由于此种给药方式所引起的血液稀释及血液粘度下降的结果。它提示在冠脉狭窄时,血液粘度对狭窄远端的心肌血供可能是一个相当重要的因素,降低血液粘度可能并不亚于扩血管药物的作用。  相似文献   
65.
This paper describes the development and piloting of a comprehensive educational programme about recognition and management of depressive illness in primary care. Full evaluation of the effectiveness of the programme is currently underway in a randomized controlled trial, the Hampshire Depression Project (HDP), involving 56 general practices. The programme consists of clinical practice guidelines, practice-based seminars and follow-up sessions. Each part of the programme has been designed to be flexible, clinically oriented and relevant to all members of the multidisciplinary primary care team. The pilot study established the need for a systematic approach to the access of practices and practice teams, and the organization and process of the seminars. Application of this approach was associated with excellent attendance in the main programme.  相似文献   
66.
Medical students are allocated little curriculum time for exposure to expert systems. ESTA, a computer model of an expert system, was developed to make best use of this time. The nature of the students' interaction with ESTA is described, and their reactions to the expert system concepts and the place of expert systems in medicine are presented. A discussion of these reactions draws some conclusions about teaching expert systems in particular, and computers in general, in the basic medical course.  相似文献   
67.
A structured clinical examination has been an integral component of the final-year examinations conducted by the Departments of Medicine and Surgery at the University of Adelaide for the last 8 years. It has been used as an alternative to the traditional clinical examination. This paper describes the results of ongoing student and examiner surveys carried out to determine their views and satisfaction with this new approach. It also briefly discusses the feasibility of introducing such an examination into a conventional medical school environment. The surveys showed a remarkable level of acceptance and support by both students and examiners. This positive reaction has been maintained over the 8-year period. The main reasons seem to be its perceived relevance and fairness. Students also appear to be directing their learning in a direction thought desirable by teachers. No significant problems have been encountered with the practical implementation of the method.  相似文献   
68.
Quantitative assessment of diagnostic ability   总被引:2,自引:0,他引:2  
This paper describes variables critical to diagnostic thinking that are based on research by Bordage and Grant & Marsden on the diagnostic thinking of medical students and experienced doctors. The purpose of the study is to use their findings to develop an inventory of diagnostic thinking. A 56-item diagnostic thinking inventory was initially developed; each item contains a stem followed by a 6-point, semantic differential scale. The inventory is designed to measure two aspects of diagnostic thinking: the degree of flexibility in thinking and the degree of knowledge structure in memory. The specific goal of the study is to determine which items discriminate best between weaker and stronger diagnosticians and to reduce the inventory to only those items which significantly contribute to the overall score. Thirty subjects from nine groups, each representing a distinct phase of medical education and clinical practice, participated, namely first- and third-year clinical medical students, house officers, senior house officers, registrars, senior registrars, consultants, trainees in general practice, and general practitioners, all from the UK (n = 270). Discrimination indices were calculated for each item. The revised version of the inventory contains 41 items. All the subjects found the exercise meaningful and the resulting scores showed variance and discrimination. The inventory will eventually be used to assess individual student's and clinician's diagnostic thinking and to plan ways of improving their diagnostic thinking.  相似文献   
69.
The Adelaide Diagnostic Learning Inventory (ADLIMS) is a measure of learning styles and learning pathologies that was designed to investigate the impact of traditional approaches to learning versus problem-based learning and to identify students whose approach to learning tasks predicted poor academic performance. In this study, some important psychometric properties of the ADLIMS were examined, including its factor structure. In this study, factor replicability across samples was argued to provide a more robust and psychologically meaningful factor solution than that which can be obtained using traditional mathematical criteria. The results of the factor analysis did not confirm the presence of the four factor solution earlier reported for the ADLIMS, but did identify three clear factors that had very high replicability. An inspection of the items comprising these three factors showed that factor 1 tapped subjective distress related to poor study habits, lack of motivation to study, and distraction from social activities. Factor 2 tapped distress arising from high achievement expectations that were hampered by superficial or disorganized study habits that did not enable the student to grasp the relationships between concepts and ideas. Factor 3 tapped positive feelings and a sense of satisfaction associated with a problem-based approach to the learning of new study material. Although the internal reliability of the ADLIMS subscales met the requirements of a measure to be used in general research such as in the investigation of correlates among groups of medical students, they did not meet the higher requirements of a measure to be used to identify or predict individuals with pathological learning styles.  相似文献   
70.
This paper reports an attempt to develop self-directed learning skills in second-year medical students by introducing case-based projects into the gross anatomy course at a long-established medical school. The programme and students' responses to a questionnaire completed at the end of the year are presented. Information on the various resources used by students to find information is given. The performance of students in the case-based components of the course has been evaluated and also in the more traditional end-of-year written examination. The data confirm that students have recognized that the projects were about obtaining a deeper understanding of the anatomy, and the programme appears to have promoted the use and study of library texts.  相似文献   
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