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991.
The aim of this study was to determine the influence of socio-demographic and professional factors on physicians' attitudes to the terminally ill. Between May 1992 and May 1993, a survey was conducted in the province of Pordenone (north-east, Italy) in order to analyse a number of specific issues, such as emotional involvement, the need for aggressive treatments and the communication of diagnosis and prognosis. After obtaining a list of board-certified physicians from the Medical Association office in Pordenone, a modification of the cancer questionnaire of Haley and Blanchard (QSPT) was mailed to 916 doctors. Of these, 605 (60%; 487 male, 118 female; mean age 41 ± 11 SD) returned the completed questionnaire. Within the group of responders, we identified three main subgroups, according to their type of activity: general practitioners (175, 29%), hospital doctors (235, 39%) and other doctors (195, 32%). In age, sex and activity, the only significant difference between responders and non-responders was age (mean age 41 and 43 years respeetively). Most of the responders (77%) stated that they were able to deal with the terminally ill patient and his/her needs; 44%, however, admitted that patients' anxiety is sometimes unbearable. For the vast majority of the doctors polled (91%), providing a comfortable environment for an incurable patient was more important than pursuing aggressive treatment, but only 44% were convinced of the uselessness of aggressive care. To the question on whether to disclose information about imminent death to allow patients to prepare spiritually, 37% answered No, 38% Yes, and 25% were uncertain. Almost all responders (95%), however, believed in the beneficial effect of hope on the terminally ill. Ourresults suggest that doctors' professional and, most of all, sociodemographic and cultural factors determine the relationship with the patient on both the emotional and the clinical decision-making levels.  相似文献   
992.
Purpose: To investigate possible associations between genetic markers and Primary Open-Angle Glaucoma (POAG). Methods: A number of genetic markers were typed in 84 unrelated patients with POAG and compared with a random sample of healthy individuals. The markers were Transferrin, Group Specific Component, G1m (1), G1m (2) and G3m (5) Allotypes, Adenylate Kinase, Adenosin Deaminase, Glyoxalase I and Acid Phosphatase and PCR-based markers HLA-DQA1 and D1S80. Results: No significant differences were found except the strong association between the group of POAG patients and Acid Phosphatase ACP*C allele (2 = 32.86; p < 0.0001). Conclusions: Since Acid Phosphatase gene is localized to chromosome 2p23, this result could be a first comprehensive step in the localization of POAG genes.  相似文献   
993.
Exogenous DNA damaging agents must be considered in the context of endogenous reactive species which have the potential to damage DNA. Although a no-effect level for a DNA-damaging compound may not exist, it may be feasible to define a level where reducing exposure to the compound is no longer the most effective way of reducing human risk. Modifying environmental factors which affect human response to damage may be the better strategy. Although a number of rare human syndromes are associated with a reduced ability to repair DNA damage, it is not clear how wide is the range of genetic variation in repair capacity among normal individuals. Studies with DNA repair-deficient human syndromes indicate that processes other than mutation and DNA repair must be involved in the development of cancer, and these processes may represent new sources of variation in human response to genotoxic agents.  相似文献   
994.
本文对11例食管平肌瘤的临床病理X线表现进行分析,本病临床症状轻微,具有典型粘膜下良性肿瘤膨胀性生长的病理特征,X线检查能充分反映其病理基础.除边线光滑的腔内充盈缺损或范围一致的腔内外肿块、“环形征”、粘膜不同程度挤压等固有X线特征外,作者认为“扇形增宽皱襞”、“肿瘤移动征”等特异征象,对诊断也很有帮助.术前诊断主要依靠食管钡餐检查.文中并讨论了鉴别诊断.  相似文献   
995.
卵巢恶性中胚叶混合瘤12例临床分析   总被引:6,自引:0,他引:6  
Li H  Shi S  Zhang W 《中华肿瘤杂志》1998,20(6):460-462
目的探讨卵巢恶性中胚叶混合瘤的临床特点、治疗及预后因素。方法对我院1983年~1997年收治的12例卵巢恶性中胚叶混合瘤的临床资料进行回顾性分析。按FIGO分期(1985年),Ⅱ期4例,Ⅲ期6例,Ⅳ期1例,不详1例。组织学分类:同源性8例,异源性4例。12例均接受肿瘤细胞减灭术。术后辅助化疗11例,其中3例又追加盆腔放疗。结果全组平均生存24个月,2,5年生存率分别为33.3%(4/12)和8.3%(1/12)。Ⅱ和Ⅲ期生存2年以上者均为2例,Ⅳ期1例在1年内死亡。同源性8例中,4例生存2年以上,异源性4例均在2年内死亡。综合治疗11例中,5例在1年内死亡。单纯手术1例在6个月内死亡。结论卵巢恶性中胚叶混合瘤恶性度高,预后差。其组织学类型、分期及治疗方法与预后有关,应采用手术与化疗和(或)放疗的综合治疗  相似文献   
996.
Human tumors exhibit two fundamentally important characteristics, extensive genetic alteration and clonality. Although it is still unclear to what extent tumors have an elevated mutational burden as compared with normal tissue, their clonality results in their ready detection. Thus, assaying tissues for clonal alterations at frequently mutated microsatellite loci represents a viable approach to cancer diagnosis. The most remarkable extension of this concept is that not only can cancer cells be detected in biological samples, but tumor DNA can also be directly detected in the serum or plasma of patients with some forms of cancer. This recent finding is currently being explored but may represent an important contribution to future diagnostic strategies.  相似文献   
997.
A seminested RT-PCR (nRT-PCR) was used to detect picornavirus (PV) RNA in cell cultures inoculated with rhinoviruses (HRVs) and enteroviruses (EVs). PCR tests in which a primary "touchdown" PCR was followed by secondary reactions using PV or HRV specific primers were able to differentiate HRVs of 48 serotypes from EVs. PVnRT-PCR and HRVnRT-PCR were then used to test nasal and throat swabs from adult subjects with naturally acquired respiratory virus infections. The swabs were also analysed for respiratory viruses by cell culture techniques and the rates of PV identification by the two methods were compared. PVnRT-PCR was found to be at least five times more sensitive than cell culture for the detection of PVs in these clinical specimens. Paired acute and convalescent serum samples were tested for complement fixing antibodies to adenovirus, influenza A and B, respiratory syncytial virus, parainfluenza viruses 1, 2, and 3, Myco plasma pneumoniae, and Chlamydia psittaci. An enzyme-linked immunosorbent assay (ELISA) was used to detect rises in antibody level to coronavirus types 229E and OC43. The overall rate of pathogen identification in 159 swabs from adult asthmatics increased from 28% when only cell culture and serology were used to 57% when these methods were supplemented by PVnRT-PCR. © 1993 Wiley-Liss, Inc.  相似文献   
998.
Summary Cardiac thrombosis due to atrial fibrillation (AF) has been recognized as the most common cause of cerebral embolism. However, sometimes no macroscopic thrombus is found at autopsy in the heart of a victim of this type of cerebral embolism. We investigated morphological changes in the left atrial endocardium of 31 patients (including 21 cases with AF) who had died of cerebral embolism. Rough endocardium (RE) seen macroscopically provided evidence for the existence of atrial thrombosis. The RE that appeared in AF cases was due to a granular and wrinkled appearance of the endocardium associated with oedematous and fibrous thickening. Fibrin-thread deposits were also always distinguishable. Mural thrombi and oedema with neutrophil infiltration in the subendocardium could be seen under the microscope. Small areas of endothelial denudation and thrombotic aggregations were commonly observed by scanning electron microscopy (SEM). These SEM lesions were significantly more frequent in cases with AF than in controls (P< 0.001). The diagnostic success rate for atrial thrombosis among cases with AF increased from 33.3% to 81% when thrombi proven by histological investigation of the areas with RE were added. Left atrial RE may be an anatomically relevant finding for the existence of atrial thrombosis with AF, when the thrombosis cannot be detected upon gross observation at autopsy.  相似文献   
999.
Summary The evaluation of computer expert systems, a promising diagnostic tool for future application in clinical medicine, is of great importance. We present here the evaluation of our expert system, RHEUMA. It is stressed, that repeated retrospective testing and updating of an expert system and its subsequent repeated assessment in clinical use and surroundings is mandatory. This increases the diagnostic accuracy of the system. For our system this is demonstrated under three separate conditions. In the first study the information available for the computer system (mainframe) came from medical histories only. Here an error rate of about 25% — similar to that of physicians themselves using the same information — was observed in 358 outpatients, compared to the final diagnoses of physicians also relying solely on information from medical histories. In a second step a completely new system on a personal computer was developed with all relevant diagnostic information. The error rate of this system (0.4%) was much too optimistic because the knowledge base was changed during the study, affecting about 30% of the 282 prospectively recruited outpatients. In a third step the efficacy of the expert system was tested in an additional hospital without the diagnostic involvement of the first testing clinic. The error rate of the system without changing the knowledge base reached 11% in 51 outpatients in this rheumatology clinic. This result reflects the diagnostic accuracy of the system today. Its ability to specify the same diagnoses which clinical experts reached approached 90%. Considerable time is needed for such prospective testing, with repeated updating of the knowledge base — in our case for both the two systems and field studies of 2 years each. Further prospective field testing with physicians not specialized in rheumatology and with a larger number of patients is necessary before the system can be used in clinical routine.Dedicated to Prof. Dr. N. Zöllner on the occasion of his 70th birthday  相似文献   
1000.
Intra-anal intussusception was diagnosed in eight of 39 patients on evacuation proctography. Posteroanterior views revealed prolapse of the infolded rectum into the anal canal on straining in seven of eight patients, associated with splaying open of the anal canal and sudden distal movement of the fold during prolapse. Similar changes were seen in four of 31 patients in whom intussusception had not been diagnosed on lateral evacuation proctography. The pattern of the collapsed rectum was assessed for fold length, thickness, and angulation in relation to the midline of the rectum. Infoldings that prolapsed were closer to the anorectal junction on stress (mean 14.6 42.4 mm, p < 0.0001) showed greater change in height between rest and strain (28.8 14.6 mm, p < 0.05) and became more acutely angled during straining (41.9 5.3°, p < 0.01). Intra-anal intussusception may be missed in 33% (four of 12 patients) on routine evacuation proctography. Posteroanterior stress proctography is a simple supplementary examination to validate intussusception.  相似文献   
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