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AIMS: The sympathetic nervous system plays a central role in cardiac growth but its overstimulation is associated with increased mortality in patients with chronic heart failure. Pre-synaptic alpha2-adrenoceptors are essential feedback regulators to control the release of norepinephrine from sympathetic nerves. In this study we tested whether a deletion polymorphism in the human alpha2C-adrenoceptor gene (alpha2CDel322-325) affects progression of heart failure in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: We genotyped and phenotyped 345 patients presenting with DCM in the heart transplant unit of the German Heart Institute, starting in 1994. Patients were treated according to guidelines (99% ACEI, 76% beta-blockers) and were followed until December 2002 or until a first event [death, heart transplantation, or implantation of a left ventricular assist device (LVAD) for a life-threatening condition] occurred. Mean follow-up time was 249 weeks (4.9 years) in event-free patients and 104 weeks (2 years) in patients with events. During follow-up, 51% of the patients exhibited an event: death (18%), implantation of LVAD as bridging for transplantation (7%), or heart transplantation (25%). By Kaplan-Meier analysis, DCM patients with the deletion variant Del322-325 in the alpha2C-adrenoceptor showed significantly decreased event rates (P=0.0043). Cox regression analysis revealed that the presence of the deletion was associated with reduced death rate (relative risk: 0.129, 95% CI: 0.18-0.9441, P=0.044) and event rates (relative risk: 0.167, 95% CI: 0.041-0.685, P=0.012). CONCLUSION: Alpha2C-adrenoceptor deletion may be a novel, strong, and independent predictor of reduced event rates in DCM patients treated according to guidelines.  相似文献   
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The purpose of this study was to assess the effect of atherosclerosis on the regulation of limb blood flow. To examine this issue, the reactivity of resistance and conduit vessels was evaluated in 11 patients with peripheral atherosclerotic disease and six control subjects. Responsiveness of resistance vessels was measured by venous occlusion plethysmography. Responsiveness of conduit vessels was determined by quantitative angiography to measure the diameter of the superficial femoral artery. To distinguish endothelium-dependent vasodilation from that caused by direct smooth muscle relaxation, each participant received intra-arterial infusions of methacholine and nitroprusside, respectively. Flow-mediated dilation of the superficial femoral artery was determined during reactive hyperemia. Vasoconstrictor function was determined by the infusion of phenylephrine. Methacholine reduced calf vascular resistance in the control subjects but not in the patients with atherosclerosis (-64 +/- 11% versus 6 +/- 18%, p less than 0.01). Nitroprusside decreased calf vascular resistance comparably in each group (-51 +/- 5% versus -42 +/- 4%, p = NS). The vasoconstrictor effect of phenylephrine was similar in each group (105 +/- 30% versus 108 +/- 22%, p = NS). In the superficial femoral artery, the vasodilator responses to both methacholine (20 +/- 4% versus 1 +/- 4%, p less than 0.05) and nitroprusside (19 +/- 4% versus 5 +/- 4%, p less than 0.05) were blunted in the atherosclerotic patients as was the vasoconstrictive response to phenylephrine (-15 +/- 1% versus -1 +/- 5%, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A infant with stenoses of the colon transversum and the sigmoid colon was successfully treated by transverse colotomy on the 31st day of life. A resection of the stenotic bowel with anastomosis was performed 8 months later.  相似文献   
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The American College of Radiology (ACR) and the American College of Cardiology Foundation (ACCF) have jointly developed a method to define appropriate utilization of cardiovascular imaging. The primary role of this method is to create a series of documents to define the utility of cardiovascular imaging procedures in relation to specific clinical questions, with the aim of defining what, if any, imaging tests are indicated to help to determine diagnosis, treatment, or outcome. The methodology accomplishes this aim through the application of systematic evidence reviews integrated with expert opinion by means of a rigorous Delphi process. By obtaining broad input during the development process from radiologists, cardiologists, primary care physicians, and other stakeholders, these documents are intended to provide practical evidence-based guidance to ordering providers, imaging laboratories, interpreting physicians, patients, and policymakers as to optimal cardiovascular imaging utilization. This document details the history, rationale, and methodology for developing these joint documents for appropriate utilization of cardiovascular imaging.  相似文献   
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Transcatheter embolization of the gastroduodenal artery with Gelfoam was performed in 12 patients undergoing percutaneous hepatic artery catheterization for infusion chemotherapy of metastatic liver disease. The purpose of the embolization was to prevent chemotherapeutic drugs from reaching the stomach and duodenum and thereby inducing gastrointestinal toxicity in patients in whom the catheter tip could not be satisfactorily positioned beyond the gastroduodenal origin. Embolization proved safe and effective in eight cases. Three other patients experienced clinical problems that may or may not have been related to embolization. The final patient had a significant complication (necrosis of the pancreatic head and gastric mucosa) that was felt to be directly related to the embolization. Transcatheter gastroduodenal occlusion may help reduce gastrointestinal toxicity of intraarterial infusion chemotherapy. However, it may on occasion be associated with significant complications, particularly in patients who are debilitated due to metastatic disease.  相似文献   
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PURPOSE: To evaluate the safety and effectiveness of retrieval of the Günther Tulip inferior vena cava (IVC) filter. MATERIALS AND METHODS: This was a nonrandomized, single-armed, multicenter prospective investigation. Patients at temporary high risk for pulmonary embolism (PE) or deep vein thrombosis (DVT) who did not require a permanent filter were eligible. Forty-one patients received 42 Günther Tulip filters: 22 men and 19 women with a mean age of 47.7 years. Indications for filter placement included prophylaxis, PE, and DVT. Three months after filter retrieval, contrast agent-enhanced computed tomography of the abdomen, jugular vein ultrasonography, and clinical follow-up were performed. RESULTS: The filter retrieval rate was 57% (23 of 41). Günther Tulip filters were removed at a mean of 11.1 days (range, 2-14 d). The technical and clinical success rates for filter retrieval were both 100%. One placement complication and two protocol deviations occurred. These patients were excluded in terms of retrieval-related outcomes. One case of PE occurred with a filter in place, and one filter migrated to the heart. There were no acute complications caused by filter retrieval. At 3-month follow-up, there was no recurrent PE, DVT, jugular vein occlusion, or IVC stenosis or occlusion. CONCLUSION: In this multicenter study, retrieval of the Günther Tulip filter was safe and without recurrent thromboembolic events or evidence of IVC or jugular vein damage at 3-month follow-up.  相似文献   
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