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Because risk factors for heart failure (HF) cluster in persons with peripheral artery disease (PAD), the authors conducted a meta-analysis to examine the prevalence of HF in individuals with PAD. MEDLINE searches were performed to review all PAD clinical trials (1966-2003). Expected control population prevalence rates for HF were derived from the National Health and Nutrition Examination Survey (NHANES) database. In total, 11,304 patients were evaluated. The average age of the patients was 67+/-5 years. The prevalence of HF in patients with PAD was 7.9% (range, 5.3%-13.9%) compared with an expected prevalence of 4.1%(range, 3.7-4.5%). The relative risk for increased HF prevalence among those with PAD was 1.9 (range, 1.35-3.10; P<.001). Thirteen (range, 7-19) PAD patients needed to be screened to detect 1 case of HF. The presence of PAD is associated with a 2-fold increase in the prevalence of HF. The use of PAD as a risk marker for underlying HF may enhance the effectiveness of screening criteria for HF detection.  相似文献   
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Selection of patients for acute-stroke therapy has traditionally been based on rigid time criteria in clinical trials. Recent advances in radiographic imaging have allowed clinicians to estimate brain physiology and thus utilize radiographic parameters to select patients for acute-stroke therapies. Both a better understanding and the quantification methods of salvageable tissue versus irreversibly injured tissue can help guide clinicians to which treatment modality to utilize. The evolution of endovascular techniques to treat acute stroke has resulted in treatment modalities that include mechanical and chemical methods to revascularize occluded cerebral arteries. Prior technical limitations to accessing distal-cerebral arteries have been partially overcome by modifications in technology. Patient and treatment-modality selection can help reduce hemorrhagic complication rates and also potentially increase revascularization rates, which may translate into improved clinical outcomes. We review the recent advances in radiographic imaging that have advanced patient selection in treating acute ischemic stroke and also consider current endovascular treatment options that are available to interventionalists performing these procedures.  相似文献   
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In most patients with renal cell carcinoma (RCC) of clear cell subtype, there is inactivation of the von Hippel-Lindau (VHL) tumor-suppressor gene, which leads to a proangiogenic state with overexpression of vascular endothelial growth factor (VEGF). This molecular level knowledge has led to the development of multiple antiangiogenic therapies directed against the VEGF protein or the VEGF receptor. These therapies have significant clinical activity in metastatic RCC. Therefore, a therapeutic strategy based on targeting VEGF in RCC has a sound molecular basis and therapy with VEGF-targeting agents has significant clinical activity. To further improve efficacy, future research should focus on better identification of patients who will most benefit from such therapy. We reviewed the published literature regarding angiogenesis, the VHL gene, VEGF biology, and antiangiogenic therapies in metastatic RCC. This article reviews the role of angiogenesis in RCC and summarizes data regarding antiangiogenic therapy in metastatic RCC.  相似文献   
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Summary Background. Chordoid glioma, a rare tumour of the third ventricle, represents a distinct clinico-pathologic entity. Thirty nine examples have been described in the literature, mostly in females and in the third ventricle. The clinical presentation is variable but they tend to occur mostly in adults. There is only one report of a chordoid glioma in a 12 year old child. Finding. This paper describes two examples of chordoid glioma in a seven year old female child and a 70 year old male respectively. Radiologically, the paediatric chordoid glioma was located in the juxtaventricular region in the occipital horn of the lateral ventricle and was of mixed density whereas the adult patient had a typical third ventricle location with homogenous contrast enhancement. Gross total surgical removal was achieved in both but the adult patient died post-operatively due to intra ventricular bleeding and bacterial meningitis. The younger patient is doing well at the last follow up two years post-operatively. Microscopically, both showed the classic morphology of chordoid glioma. Ultrastructural examination was suggestive of ependymal differentiation. Conclusion. The younger age and unusual location are some of the rare features which need documentation and have not been described earlier. We propose that chordoid glioma is a variant of an ependymoma (WHO grade II) which arises from tanycytes and should be included in the WHO classification of brain tumors. Correspondence: Dr. Mehar Chand Sharma, M.D., Associate Professor, Department of Pathology, AIIMS, New Delhi 110029, India.  相似文献   
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