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Background  Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial. Methods and Results  The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization in reducing patients’ ischemic burdens. Conclusions  The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology. We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based management of patients with stable coronary disease. The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon; and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging.  相似文献   
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To determine the value of chest roentgenograms in the management of asymptomatic persons with positive tuberculin skin test results, we undertook a retrospective review of all tests administered by our Employee Health Service, North Shore University Hospital, Manhasset, NY, between July 1, 1983 and November 1, 1987. Of 5200 tests, 247 results were positive. Two hundred twenty-one of these charts were reviewed for roentgenographic results and the presence of symptoms. All persons were asymptomatic. Chest roentgenograms revealed the following: normal, 188; unrelated abnormalities, 24; apical pleural thickening, 5; granulomas, 2; calcified hilar node, 1; and calcified node plus granuloma, 1. We noted no active tuberculosis, nor did the chest roentgenographic results influence recommendations for isoniazid prophylaxis. We conclude that chest roentgenograms are of value in 0% to 1.3% of asymptomatic people with positive tuberculin test results. A larger study should be undertaken to further define the usefulness of chest roentgenograms in this population.  相似文献   
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OBJECTIVES: To test a possible association between the educational level (EL), cognitive performance, and neuropsychiatric features in Parkinson disease (PD). BACKGROUND: An inverse association has been reported between EL and cognitive dysfunction in patients with senile dementia of Alzheimer type but it is yet unsettled whether education has a similar effect on cognition in PD. METHODS: Seventy-two PD patients (45 males, mean age 68.7+/-11.6 y) underwent a detailed neurologic examination, a battery of neuropsychologic tests, and questionnaires for the evaluation of psychosis, sleep disturbances, and depression. According to the number of educational years, patients were divided into 3 groups: low EL (0 to 8 y), (15 patients), intermediate EL (9 to 12 y) (28 patients), and high EL (>/=13 y) (29 patients). RESULTS: Patients with a higher EL had a better cognitive function and an association was found between the patients' EL and their scores in various neuropsychologic tests mainly those sensitive to frontal lobe dysfunction. Low education was associated with an increased risk for hallucinations and a trend for more depression, delusions, and sleep disturbances. CONCLUSIONS: The association between high educational attainment and the lower risk of cognitive dysfunction suggest that education might modulate cognitive performance in PD.  相似文献   
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Brain morphology was examined using magnetic resonance imaging in 30 first-episode patients with a schizophreniclike psychosis, 15 chronic schizophrenics, and 20 neurological controls. Statistical analyses of computer-generated measurements of regions of interest were controlled for gender, age, social class, and total brain volume. Lateral ventricular size was increased in both first-episode and chronic schizophrenic patients, with greater significance on the left than on the right side. Only the chronic patients, however, had reduced temporal lobe size, which also was greater on the left side. No major correlations of regional brain morphological measurements with cognitive functioning were found, although some measurements of verbal memory were correlated with parahippocampal size. This is a report of a preliminary study that suggests that some morphological brain changes may be present at the time of first treatment for a psychotic illness, whereas others may occur later in the course of illness. Future prospective studies may determine the clinical significance of these changes and whether they progress with the development of illness chronicity.  相似文献   
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Computer software developed in our laboratory (CMATRIX) was used to design a physiological pharmacokinetic model of nicotine absorption, distribution, metabolism and excretion in man. The model accommodates inhalation of nicotine from various environmental settings and physiological conditions in man. It was also used to predict pharmacokinetic behavior of cotinine arising from nicotine metabolism. Model-predicted variations in body-fluid nicotine levels confirm that nicotine is not an acceptable quantitative marker of environmental tobacco smoke (ETS) exposure. Though cotinine provides a more stable pattern, predicted interindividual variation suggests the need for specific strict sampling and monitoring guidelines for cotinine to be a reliable quantitative marker.  相似文献   
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Arthroscopic acromioplasty. Technique and results   总被引:3,自引:0,他引:3  
Of forty-four patients who were treated by arthroscopic acromioplasty from July 1984 through August 1986, forty were available for analysis. The average age was 43.2 years, and 86 per cent of them had participated regularly in sports but were disabled due to symptoms of impingement. All patients had had a minimum of six months of non-operative therapy. The final diagnoses, which were based on the findings at arthroscopy and on clinical examination, plain radiographs, and arthrograms, were Stage-II impingement in twenty-four patients, a partial-thickness tear of the rotator cuff in six, and a full-thickness tear of the rotator cuff in ten. The shoulders were scored before the operation and again at follow-up. Preoperatively, thirty-six shoulders were rated as poor and four, as fair. After a minimum follow-up of twelve months (average, seventeen months), the scores had increased in all but one patient. The result was rated good or excellent in twenty-nine (73 per cent) of the forty patients: twenty of the twenty-four who had Stage-II impingement, four of the six who had a partial-thickness tear, and six of the ten who had a full-thickness tear. The over-all average time to return to work was nine days, and the average time to return to sports was 2.4 months. Of the thirty-three patients who had participated in sports, twenty-five (76 per cent) had returned to sports activity at the time of the most recent follow-up. The average time until full recovery was 3.8 months. There were no complications, and, over-all, thirty-eight (92 per cent) of the forty patients were satisfied with the result. In four patients, the result was a failure, and three of the four had a reoperation that relieved the symptoms.  相似文献   
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It is unclear whether ovarian carcinomas develop from malignant transformation of benign precursors or whether they arise de novo. Thus, histologically benign or low malignant potential components found in heterogeneous ovarian carcinomas may be remnants of pre-existing lesions that progressed to malignancy or, alternatively, elements that arose independently (de novo). In a third possible interpretation, they represent areas of malignant epithelium that matured. We evaluated clonal relationships of histological components in 10 heterogeneous ovarian carcinomas using fluorescence in situ hybridization and confocal microscopy. Detailed analysis of aneuploidy for chromosomes 8, 12, and 17 on intact paraffin sections revealed that two tumors were aneuploid in all components, two lacked abnormalities in benign-appearing components, and one lacked aneuploidy in both histologically benign and low malignant potential components. Histological appearance was significantly related to aneuploidy (P < 0.05). The distribution of aneuploidy among tumor components strongly supports the tumor progression theory and demonstrates that the de novo hypothesis is highly unlikely (P < 0.001). Results also indicate that benign-appearing components in heterogeneous ovarian carcinomas do not represent maturation of malignant tissue and suggest that some benign tumors that become cancerous may have genetic aberrations that predispose them to malignant transformation.  相似文献   
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