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81.
Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis.  相似文献   
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Background: Sevoflurane undergoes Baralyme- or soda lime-catalyzed degradation in the anesthesia circuit to yield compound A (2-[fluoromethoxy]-1,1,3,3,3-pentafluoro-1-propene), which is nephrotoxic in rats and undergoes metabolism via the cysteine conjugate beta-lyase pathway in those animals. The objective of these experiments was to test the hypothesis that compound A undergoes beta-lyase-dependent metabolism in humans.

Methods: Human volunteers were anesthetized with sevoflurane (1.25 minimum alveolar concentration, 3%, 2 l/min, 8 h) and thereby exposed to compound A. Urine was collected at 24-h intervals for 72 h after anesthesia. Rats, which served as a positive control, were given compound A intraperitoneally, and urine was collected for 24 h afterward. Human and rat urine samples were analyzed by19 F nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry for the presence of compound A metabolites.

Results: Analysis of human and rat urine showed the presence of the compound A metabolites [S-[2-(fluoromethoxy)-1,1,3,3,3-pentafluoropropyl]-N-acetyl-L-cysteine, (E)- and (Z)-S-[2-(fluoromethoxy)-1,3,3,3-tetrafluoro-1-propenyl]-N-acetyl-L-cyst eine, 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid, 3,3,3-trifluorolactic acid, and inorganic fluoride. The presence of 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid and 3,3,3-trifluorolactic acid in human urine was confirmed by gas chromatography-mass spectrometry.  相似文献   

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Knotting of intravascular catheters is an uncommon but a well‐recognized occurrence. The Swan–Ganz catheter (SGC) is the one that knots most commonly. A case of a knotted SGC is described in a patient with a persistent left‐sided superior vena cava, and we propose that the presence of a left‐sided superior vena cava is a risk factor for knot formation not previously reported. We review the published work on the risk factors for knot formation and on the techniques used to remove knotted SGC. We describe a technique using a gooseneck snare and Omni Flush catheter (Angiodynamics, Queensbury, NY, USA) to loosen and untie a knotted SGC.  相似文献   
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膦甲酸钠治疗疱疹病毒相关性进展性卒中26例   总被引:1,自引:0,他引:1  
李冬梅  高玉林  王永祥 《医学争鸣》2005,26(14):1267-1267
1临床资料我院神经内科200112/200203应用膦甲酸钠(PFA,foscarnetsodium)治疗进展性卒中(progressivestroke,PS)患者26例.男12例,女14例,年龄35~70(平均57±14)岁.总病程19~72d.有高血压病史19例,有短暂性脑缺血发作病史11例,有脑梗死病史3例,有冠心病病史1例.标准符合1995年第四届全国脑血管病会议脑梗死诊断标准[1],并经脑CT或MRI证实为脑梗死;发病后1wk内病情逐步或阶梯样加重,临床常规治疗不能阻止病情进展,按1995年第四届全国脑血管病会议神经功能缺损评分标准[2]评分增加2分(包括2分)以上.采用金标免疫斑点法检测患者血清中人巨…  相似文献   
87.
Optic nerve head swelling is caused by either ocular or systemic diseases of inflammatory, infective, infiltrative, compressive, or ischemic origin. Uncommonly, an isolated optic nerve head swelling without the above underlying mechanisms might also occur. Two patients presented with unilateral, isolated optic nerve head swelling. A detailed oculoneurological examination and a series of investigations failed to indicate any pathology. No probable cause for optic nerve head swelling in these patients was determined by the authors. the authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or privider of services discussed in this article. The authors also do not discuss the use of off-label products, which include unlabeled, unapproved, or investigative products or devices.  相似文献   
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