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Interobserver variability in neonatal cranial ultrasonography   总被引:1,自引:0,他引:1  
The reliability of cranial ultrasound diagnosis in the premature neonate was examined using data from an ongoing multicentre study of the epidemiology and long-term consequences of neonatal brain haemorrhage. First week ultrasound films (obtained at 4 hours, 24 hours and 7 days) from 60 study subjects were randomly selected for independent review by two groups of experienced interpreters, and results were recorded separately for observations (i.e. presence or absence of an abnormal echodense area on a film) and interpretations (i.e. presence or absence of haemorrhage or ventricular dilatation) in each hemisphere. Because of deaths in the first week of life, the total number of films examined was 138. Concordance on the presence or absence of an abnormal echodensity was examined for each individual film for three areas of interest: the germinal matrix, the ventricles and the parenchyma. Concordance on the presence or absence of haemorrhage or ventricular dilatation was examined only for the seventh-day film, or the final film prior to death. Finally, concordance was analysed with the diagnostic interpretations grouped into categories thought to differ prognostically for long-term outcome. In general, concordance was poorest for germinal matrix lesions and best for parenchymal lesions. Concordance was lower for observations made on each individual film than it was for interpretation of the final film in each case. Fifty-five of 60 cases (92%) were assigned to the same major prognostic category by both readers. Ultrasound review conferences were held periodically and there was evidence that concordance in ultrasound reading and interpretation improved during the course of the study.  相似文献   
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Predicting death from coronary heart disease using a questionnaire   总被引:4,自引:0,他引:4  
The ten-year coronary heart disease (CHD) mortality is reported for 18,322 male civil servants aged 40 to 64 according to questionnaire responses at entry into the Whitehall study. In all 1714 died, 723 from CHD. The predictive power of the questionnaire was examined with a view to its use as a screening tool in population studies. In predicting death from coronary heart disease the greatest specificity (true negative rate) was achieved with men reporting both angina (A) and a history of severe chest pain (possible myocardial infarction, PMI). This strategy (A plus PMI) achieved a specificity of 99% but a sensitivity (true positive rate) of only 7%. In contrast, in men reporting angina and/or PMI, specificity was 90% and sensitivity 29%. If this 'and/or' algorithm was extended to include the report of dyspnoea, diabetes, and/or attending a primary care physician with heart disease or hypertension, then specificity was still 85%, but sensitivity increased to 44%. This combination (11 questions in all) is therefore recommended for screening purposes. Identifying and excluding those who favour positive answers ('yes-set' responders), using questions such as the effect of weather on breathing, led to small increases in specificity but relatively large falls in sensitivity. Among subjects reporting chest pain, those who also complained of non-specific symptoms experienced only half the mortality of those with none of these additional complaints.  相似文献   
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A 91-year-old man developed a mass in the right medial canthal and lacrimal sac region, which was found histopathologically to be a poorly differentiated neoplasm. The results of a complete systemic evaluation, including urologic consultation, rectal examination, bone scan, and determination of serum acid phosphatase level, were normal. In spite of the negative evaluation for prostatic carcinoma, immunohistochemical studies using immunoperoxidase stains for prostatic-specific antigen demonstrated that the lacrimal sac tumor was metastatic carcinoma from an occult primary neoplasm in the prostate gland. The presence of tumor in the prostate gland was then confirmed by a needle biopsy. Modern immunohistochemical techniques are particularly valuable in the diagnosis of selected ophthalmic tumors in which the diagnosis cannot be determined by routine diagnostic techniques.  相似文献   
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OBJECTIVE: The objective of this retrospective cohort study was to determine whether coronary artery bypass graft (CABG) surgery is effective and cost-effective relative to medical management of coronary artery disease (CAD) in the elderly. SUMMARY BACKGROUND DATA: The aging of the U.S population and the improvements in surgical techniques have resulted in increasing numbers of elderly patients who undergo this surgery. The three randomized, controlled trials (RCTs) that established the efficacy of CABG surgery completed patient enrollment from 19 to 24 years ago excluded patients older than 65 years. Although information regarding outcomes of CABG in this population is mainly available in case series, a major lacuna exists with respect to information on quality of life and cost effectiveness of surgery as compared with medical management. METHODS: The authors retrospectively formed surgical and medically managed cohorts of octogenarians with significant multivessel CAD. More than 600 medical records of patients older than 80 years who underwent angiography at our institution were reviewed to identify 48 patients who were considered reasonable surgical candidates but had not undergone surgery. This cohort was compared with 176 patients who underwent surgery. RESULTS: The cost per quality-adjusted life year saved was $10,424. At 3 years, survival in the surgical group was 80% as compared with 64% in the entire medical cohort and 50% in a smaller subset of the medical cohort. Quality of life in patients who underwent surgery was measurably better than that of the medical cohort with utility index scores, as measured by the EuroQoL, (a seven-item quality of life questionnaire) of 0.84, 0.61, and 0.74, respectively. CONCLUSIONS: Performing CABG surgery in octogenarians is highly cost-effective. The quality of life of the elderly who elect to undergo CABG surgery is greater than that of their cohorts and equal to that of an average 55-year-old person in the general population.  相似文献   
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