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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   
3.
Recent reports provide evidence that some growth factors behave as inhibitors of the apoptosis of the endothelial cells, bringing forward the concept of vascular survival as a post-angiogenesis process. At least two different vasculature development processes occur within a tumor: the angiogenic (formation of new vessels) and the vascular survival pathway, which is devoted to the preservation of the newly-formed vessels in layers that lose contact with the adjacent normal tissue. We developed a method to assess these processes in tissue samples. We noted that differences among tumors may exist not only in the tumor angiogenic activity (TAA) but also in the vascular survival ability (VSA). One third of the highly angiogenic breast cancer cases examined had a poor ability to maintain high vessel density in inner tumor areas. Both parameters are independently related to prognosis, while VSA was directly related to tumor dimensions and node involvement. Patients with high TAA and VSA had a particularly poor prognosis. It is suggested that although cancer angiogenic activity is important for the local invasion and dissemination into vessels and lymphatics, the VSA may be important for the effective formation of viable tumor foci in lymph nodes or distant organs. Recognition and quantification of the vascular survival ability in human tumors may significantly improve the prognostic value of the assessment of tumor vasculature, and may help to stratify patients for clinical trials with novel anti-angiogenic or angiotoxic drugs. Elucidation of the pathways may provide additional targets for antiangiogenic therapy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
4.
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   
5.
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   
6.
We present a case of Ludwig's angina in a 48-y-old immunocompetent male caused by an unusual pathogen, Gemella morbillorum. The infection was complicated with mediastinitis and despite aggressive management of the disease the patient died after 12 d of hospitalization. This is the first reported case of Ludwig's angina caused by G. morbillorum and emphasizes that the disease remains a potentially lethal infection.  相似文献   
7.
AIMS: To study the effect of cardiac resynchronization therapy (CRT) on coronary and peripheral arterial circulation and to assess whether their changes are related to the improvement in patients' functional capacity and prognostically important biochemical markers. METHODS AND RESULTS: Twenty-five patients were studied (New York Heart Association classes III and IV, left ventricular ejection fraction <35%, QRS>120 ms, mean age 66 +/- 2.1 years). Coronary blood flow (CBF), forearm blood flow (FBF), and their reserve were measured by transoesophageal echocardiography (in cm/s) and venous occlusion plethysmography (in mL/100 mL/min) at baseline and following 3 months of CRT. N-terminal-pro-brain natriuretic peptide (Nt-pro-BNP) and serum adhesion molecules, sICAM-1 and sVCAM-1 levels were also assessed. CRT induced a non-significant increase in resting CBF (baseline vs. CRT: 52.1 +/- 5.5 vs. 58.2 +/- 3.6, P: NS), whereas hyperaemic CBF was increased by CRT (baseline vs. CRT: 67.8 +/- 6.8 vs. 79.8 +/- 6.2, P < 0.05). Significant increases were observed in resting FBF (baseline vs. CRT: 1.6 +/- 0.2 vs. 2.6 +/- 0.2, P < 0.05) and hyperaemic FBF (baseline vs. CRT: 2.1 +/- 0.2 vs. 3.2 +/- 0.3, P < 0.05). The per cent difference in hyperaemic FBF was related to the per cent change in Nt-pro-BNP (r = -0.71, P < 0.05) and the per cent improvement in exercise duration (r = 0.80, P < 0.05). CONCLUSION: CRT induces favourable changes in coronary and peripheral arterial function. Changes in peripheral blood flow are related to patients' improvement and may be prognostically significant.  相似文献   
8.

Background

Job burnout is one of the most serious occupational health hazards, especially, among mental health nurses. It has been attributed among others to staff shortages, health service changes, poor morale and insufficient employee participation in decision-making.

Aim

The aim of this study was to measure burnout among mental health nurses, investigate relations between burnout and organizational factors and examine potential predictors of nurses' burnout. Specifically, this study aimed to investigate whether role conflict, role ambiguity, organizational commitment and subsequent job satisfaction could predict each of the three dimensions of burnout.

Design/methodology/approach

During current cross sectional, the survey was administered to 232 mental health nurses, employed in four private psychiatric clinics in the region of Larissa, Thessaly, Greece in May 2015. Our findings were based on the responses to 78 usable questionnaires. Different statistical analyses, such as correlation analyses, regression analyses and analyses of variance were performed in order to explore possible relations.

Findings

High emotional exhaustion (EE) accounted for 53.8% of the sample, while high depersonalization (DP) and high personal accomplishment (PA) accounted for 24.4% and 25.6%, respectively. The best predictors of burnout were found to be role conflict, satisfaction with workload, satisfaction with training, role ambiguity, satisfaction with pay and presence of serious family issues.

Practical implications

These findings have implications for organizational and individual interventions, indicating that mental health nurses' burnout could be reduced, or even prevented by team building strategies, training, application of operation management, clear instructions and psychological support.  相似文献   
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10.
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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