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During the past few decades, management of patients with myocardial infarction has dramatically evolved. High-risk patients are now identified by a variety of noninvasive tests, and aggressive use of reperfusion strategies has improved clinical outcomes. Despite the benefits of reperfusion, only a few patients are eligible to receive thrombolytic therapy. Mortality rates among patients excluded from thrombolytic trials (15% to 20%) have been far greater than those eligible for treatment (3% to 10%). Because most deaths occur within the first few days of infarction, interventions designed to reduce mortality should be performed acutely. Immediate catheterization allows identification of high-risk anatomy that may benefit from surgery and allows coronary angioplasty to be performed as a reperfusion strategy (when appropriate). Furthermore, catheterization allows documentation of ejection fraction, vessel patency, number of diseased vessels, and residual stenosis, all of which have been predictive of prognosis. Conversely, frequently repeated noninvasive diagnostic tests are associated with increased cost, are generally performed in low-risk patients, and 60% to 80% of patients with myocardial infarction ultimately require catheterization anyway. It is possible that early catheterization and percutaneous transluminal coronary angioplasty when indicated may effectively risk stratify patients (eliminating the need for noninvasive testing), may reduce morbidity and mortality, and shorten the length of hospital stay.  相似文献   
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Three kinds of lectins (UEA-I, ConA, PNA) were used to study normal, dysplastic, neoplastic nasopharyngeal epithelium by lectin affinitive histochemical method. UEA-I (ulex europeus agglutinin-I) displayed membrane distribution in normal squamous epithelium, but most of nasopharyngeal carcinoma cells were negative. Notably, severe dysplastic epithelium (precancerous lesion) exhibited a strong membranous and cytoplasmic affinity, which contrasted sharply with the normal epithelium and carcinoma cells. The statistically significant difference in the content and distribution of lectin UEA-I in these three groups suggest that UEA-I is a hopeful marker for diagnosing precancerous lesion of the nasopharynx. However, PNA and ConA are of less diagnostic value.
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Both radionuclide angiography and myocardial perfusion imaging provide important insights that determine the management of patients with stable coronary artery disease. Both nuclear cardiology procedures have clearly demonstrated use in the noninvasvie identification of severe (left main or three-vessel) coronary artery disease and the noninvasive assessment of prognosis and thereby determine which patients should be sent to coronary angiography. Both radionuclide angiography and myocardial perfusion imaging provide prognostic information that is independent of resting left ventricular function and coronary anatomy and thereby influence the decision regarding which patients should be sent to coronary revascularization. This review considers the evidence supporting the uses of these nuclear cardiology procedures and provides suggestions regarding their cost-effective application.  相似文献   
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Acute stroke affects large numbers of people worldwide. It causes significant morbidity and mortality. Data support the hypothesis that the public is not familiar with either the risk factors or the signs of stroke. Educating the public about stroke may result in a lower incidence of the disease as individuals modify their risk factors, and in improved outcomes as a result of reductions in delays to treatment. There is clear and convincing evidence that reducing delays to treatment of patients with acute stroke results in improved outcomes. Public education programs should be broad-based, tailored to individual audiences, and carry a common theme.  相似文献   
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