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We describe the case of a recipient of an implantable cardioverter defibrillator with multiple syncopal episodes due both to superior vena cava obstruction and electrical instability. These complications occurred in the presence of two transvenous implantable cardioverter defibrillator leads. The patient has been managed conservatively with anticoagulants and new antiarrhythmic drugs with improvement in both his clinical problems.  相似文献   
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Tumour angiogenesis: vascular growth and survival   总被引:3,自引:0,他引:3  
Angiogenesis starts at the edge of a malignant epithelial tumour concurrently with tumour cell invasion and stromatogenesis, i.e. the formation of specific connective tissue stroma amenable to easy penetration by endothelial and tumour cells. However, as the tumour continues its growth, the edge becomes the inner tumour area, and a new invading tumour front is formed by the multiplying malignant cells which outflank the initial edge. This process, which repeats itself again and again, forms the "relay race" model of tumour vascular growth and regression. At the heart of the tumour unfavourable environmental conditions prevail -- hypoxia, acidity, lack of nutrients, failure of waste removal, and apoptosis rather than proliferation. Blood vessels and tumour cells are greatly decreased, but do not vanish, as tumour cells are shifting to anaerobic glycolysis, and blood vessels are turning into anti-apoptotic pathways -- vascular survival ability (VSA). Thus, assessing vascular density (VD) by simply counting "hot spots" at the edge of a tumour, where conditions are most favourable, is futile; it may reflect tumour angiogenic activity (TAA), but is not representative of genuine tumour vasculature. By combining vessel counts at the invading tumour front with those of the inner tumour areas a complete picture of tumour VD can be achieved. The thus formed four patterns of vascularization, designated as "edvin" (edge vsinner tumour area), are: edvin 1: low TAA/low VSA; edvin 4: high TAA/high VSA; edvin 2: low TAA/high VSA; and edvin 3: high TAA/low VSA. It is expected that this scheme will prove useful in the field of chemoradiotherapy and anti-angiogenic treatment.  相似文献   
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c-erbB-2-positive breast carcinomas are highly aggressive tumors. In vitro data on breast cell lines showed that c-erbB-2 enhanced translational efficiency of hypoxia inducible factor-1alpha (HIF1alpha) production (Laughner et al., Mol Cell Biol 2001;21:3995-4005). We investigated the clinical correlate of this observation to assess whether c-erbB-2 expression was related to HIF1alpha expression, angiogenesis, and prognosis. A series of 180 breast carcinomas of known c-erbB-2 status (90 c-erbB-2-positive and 90 c-erbB-2-negative carcinomas) were stained immunohistochemically for HIF1alpha and CD31 endothelial cell antigen. c-erbB-2 positivity was clearly related to HIF1alpha protein expression and high angiogenesis. However, prognosis was decreased only in cases with simultaneous c-erbB-2 and HIF1alpha expression. If activation of c-erbB-2 in humans results in overexpression of HIF1alpha independently of conditions of hypoxia, as occur in experimental studies, this interaction may represent a main pathway conferring clinical aggressiveness to c-erbB-2-positive breast tumors.  相似文献   
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The aim of the current study was to investigate whether a Total Lifestyle Index (TLI), including adherence to the Mediterranean diet, sleep duration, physical activity and engagement in activities of daily living, is associated with cognitive health over time and dementia risk, in a representative cohort of older people. A total of 1018 non-demented community-dwelling older adults ≥65 years old (60% women) from the HELIAD study were included. A comprehensive neurological and neuropsychological assessment was conducted at baseline and at the 3-year follow-up evaluating cognitive functioning, and a dementia diagnosis was set. Diet, physical activity, sleep duration and engagement in activities of daily living were assessed using standard, validated questionnaires at baseline. Sixty-one participants developed dementia at follow-up; participants who developed dementia were older and had fewer years of education compared with participants with normal cognition. With the exception of sleep duration, participants with normal cognition at follow-up scored higher in the individual lifestyle factors compared to those who developed dementia. Regarding TLI, values were lower for participants with dementia compared with those with normal cognition. Each additional unit of the TLI was associated with 0.5% of a standard deviation less decline per year of the Global Cognition score, whereas for each additional unit of the TLI, the risk for dementia was reduced by 0.2% per year (p < 0.05). Our results suggest that greater adherence to a healthy lifestyle pattern is associated with a slower decline of cognitive function and reduced dementia risk.  相似文献   
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PURPOSE: To report the technique for deploying a 3-part endovascular graft onto the native aortic bifurcation for greater stent-graft stability. TECHNIQUE: The Zenith Composite Endovascular Graft is a 3-part system consisting of a proximal tubular body with an uncovered Gianturco Z stent, a distal bifurcated body, and a contralateral leg. Proximally, 8-mm flexible interstent gaps facilitate precise infrarenal aortic placement, even in angulated necks. Technically, the bifurcated part is deployed first and pulled down to the aortic bifurcation, while the tubular main body and contralateral leg deployment follow. Using this technique to accommodate the graft onto the natural aortic bifurcation, distal stability can be enhanced and graft migration minimized. CONCLUSION: The Composite configuration can be an alternative to ensure a higher security index in difficult anatomies. It may be beneficial in patients with short (10-15 mm), angulated (>60 degrees ), or conical necks and deserves investigation in these patient populations.  相似文献   
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The endometrial hyperplasias form a spectrum of proliferative lesions, not all of which conform to conventional definition of hyperplasia. For whilst most hyperplastic lesions are composed of cells normally occurring in the late proliferative phase endometrium, there are those few which consist of genuine atypical cells. Lesions of this type, so-called “atypical endometrial hyperplasias”, tend to merge imperceptibly with well differentiated endometrioid adenocarcinomas, giving rise to major challenges: First and foremost, what are the very essential criteria that should be met before diagnosing such a lesion? And what are the very least that should be insisted upon for diagnosing malignancy once an atypical endometrial hyperplasia has been established? What is its true nature and how should ideally be classified? Other less conflicting, but equally interesting, aspects of endometrial hyperplasia which are covered in this account include the conventional hyperplasias, i.e. those lacking cytological atypia, and the overall incidence, risk factors and treatment of the disease. It is worth noting that “pure” stromal cell proliferations are, in itself, not necessarily neoplastic, for many take the form of endometrial stromal hyperplasia.  相似文献   
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