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In chronic heart failure diuretic drugs improve central hemodynamic variables and cardiac pumping secondary to altered plasma and extracellular volumes; humoral markers of these changes include increased plasma renin and aldosterone levels. The latter increases are maximal over the first week but decline with chronic therapy. The plasma alpha-ANP levels show a reciprocal effect; these data are compatible with a rapid contraction of the plasma volume which is sustained during chronic therapy.The acute hemodynamic actions of diuretic agents reflect both immediate and direct vascular actions and also effects secondary to diuresis (volume redistribution). At rest substantial reductions in pulmonary wedge pressure (–29%), with a consequent fall in cardiac output (–10%), are described. Total systemic vascular resistance initially increases but reverse autoregulation over subsequent weeks returns this elevation gradually towards control values. Tolerance to these initial hemodynamic effects does not occur with maintained therapy; moreover, echocardiographic markers of contractility and exercise capacity may increase. The early venodilator effects of diuretic drugs can be attributed to prostaglandin release and the initial pressor actions to activation of the renin angiotensin system; these vascular actions may have limited relevance to long-term beneficial effects on hemodynamics. Direct pulmonary vasodilation and improved pulmonary compliance remain an interesting finding. Although most patients are both symptomatically and hemodynamically improved at rest, the actions during exercise are more varied. Some individuals with severely impaired left ventricular function show little hemodynamic improvement, whereas those with milder dysfunction usually benefit; in the main this is probably related to the latter being on a steeper cardiac function curve. The impact of diuretic therapy on the underlying disease process is unclear; however, there is little convincing evidence of remodelling or improvement in intrinsic performance (as distinct from that induced by altered loading conditions).  相似文献   
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International Journal of Legal Medicine - Sudden cardiac death (SCD) related to atherosclerotic coronary artery disease (ACAD) resulting in myocardial infarction is the most prevalent cause of...  相似文献   
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The MRE11/RAD50/NIBRIN complex, a protein complex that repairs DNA double-strand breaks, could serve as an early marker for new lesions in pancreatic cancer. We determined the expression of MRE11, RAD50 and NIBRIN, and their possible prognostic value regarding survival.  相似文献   
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Colonization/infection with multidrug-resistant bacteria (MDRB) such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae, is an increasing problem not only in hospitals but also in long-term care facilities. The aim of this study was to determine the prevalence as well as the risk factors of colonization/infection with MRSA, VRE, and ESBL producing Enterobacteriaceae in geriatric clinics, nursing homes, and ambulant care in Frankfurt am Main, Germany. 288 patients from 2 geriatric clinics (n = 46), 8 nursing homes (n = 178), and 2 ambulant care facilities (n = 64) as well as 64 staff members were screened for MDRB in the time period from October 2006 to May 2007. 58 patients (20.1%) and 4 staff members (6.2%) were colonized with MDRB. Among patients, 27 (9.4%) were colonized with MRSA, 11 (3.8%) were screened positive for VRE, and 25 (8.7%) were found to be colonized with ESBL producing Enterobacteriaceae. Prevalence of MDRB in geriatric clinics, nursing homes, and ambulant care facilities were 32.6%, 18.5%, and 15.6%, respectively. Significant risk factors for MDRB were immobility (OR: 2.7, 95% CI: 1.5–4.9; p = 0.002), urinary catheter (OR: 3.1, 95% CI: 1.7–5.9; p < 0.001), former hospitalization (OR: 2.1, 95% CI: 1.1–4.0; p = 0.033), and wounds/decubiti (OR: 2.3, 95% CI: 1.5–4.9; p = 0.03). Finally, the high level of MDRB in geriatric clinics, nursing homes, and ambulant care points to the importance of these institutions as a reservoir for dissemination.  相似文献   
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