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A case-control study of squamous cell carcinoma of the upper aerodigestive tract conducted in Heidelberg and Giessen (FRG) provided information on occupational factors in 200 patients and 800 controls (adjusted to sex, age and area of living; 4:1 matched design). The number of subjects exposed to wood dusts, organic chemicals, coal products or to cement was significantly elevated in the tumour group. An increased risk for head and neck cancer was observed after exposition to wood dust (RR = 2,2), organic compounds (RR = 2,4), coal products (RR = 2,7) and especially to cement (RR = 4,4). The cancer risk due to cement exposition showed a positive correlation to the duration of exposition and remained significantly elevated after adjustment for alcohol and tobacco consumption.  相似文献   
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BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
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Exercise and work potential of a patient with coexistent myophosphorylase and myoadenylate deaminase (AMPDA) deficiency was compared with that of three patients with myophosphorylase deficiency alone. The patient with the combined defect failed to produce an abnormal rise in serum ammonia or hypoxanthine as seen in the other patients after forearm exercise. Maximum oxygen consumption and work rates during cycle ergometer testing were similar in all patients, but well below controls. The occurrence of two defects involving short-term energy metabolism in muscle presents an opportunity to define further the metabolic role of AMPDA.  相似文献   
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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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In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed.  相似文献   
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Open, Double-Blind and Long-Term Study of Vigabatrin in Chronic Epilepsy   总被引:5,自引:4,他引:1  
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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