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141.
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   
142.
Levodopa (L-dopa) and subthalamic nucleus (STN) stimulation treatments have been associated with both improvement and exacerbation of dysarthria in Parkinson's disease (PD). We report four cases illustrating variant responses of dysarthria to dopaminergic and STN stimulation therapies. Patients' motor disability and dysarthria were perceptually rated by the Unified Parkinson's Disease Rating Scale (UPDRS) in four conditions according to medication and STN stimulation. Dedicated software packages allowed acquisition and analysis of acoustic recordings. Case 1, who had a severe off period aphonia, experienced improvement of speech induced by both levodopa and STN stimulation. In Case 2, both treatments worsened speech due to the appearance of dyskinesias. Case 3 had a dysarthria exacerbation induced by STN stimulation with parameters above optimal levels, interpreted as current diffusion from the STN to corticobulbar fibers. In Case 4, dysarthria exacerbation occurred with stimulation at an electrode contact located caudally to the target, also arguing for current diffusion as a potential mechanism of speech worsening. The presented cases demonstrated variant effects in relation to L-dopa and STN stimulation on speech. It seems that motor speech subcomponents can be improved like other limb motor aspect, but that complex coordination of all speech anatomical substrates is not responsive to STN stimulation. These hypotheses may be helpful for better understanding and management of STN stimulation effects on motor speech and skeleton-motor subsystems.  相似文献   
143.
刘万忠  左阿玲 《药学学报》1992,27(4):294-298
报道一种新型结构的全固态乌头碱电化学检测器的研制及其在流动注射分析中的应用。采用流动注射分析法对川乌、草乌及其中成药(小活络丸)中剧毒成分(双酯型生物碱)进行了测试,方法简便快速,结果同光度法接近。本文还提出了电化学法研究乌头碱水解动力学原理。在pH 6.5,温度98℃的条件下测得乌头碱水解成苯甲酰乌头碱的速度常数为1.36×10-2min-1。  相似文献   
144.
Factor XIII (FXIII) deficiency is a rare autosomal recessive congenital disorder of haemostasis, associated with a high risk of intracranial haemorrhage. Intracranial haemorrhage can result in neurological sequelae including seizure disorders. In some cases, medically intractable epilepsy led to epilepsy surgery. Little has been reported on the management of FXIII deficiency during surgery, and there is only a few data on the management, safety and efficacy of epilepsy surgery in the patients with haemostatic disorder. We report here an epilepsy neurosurgery in a case of severe FXIII deficiency.  相似文献   
145.
146.
The effects of a chronic ethanol drinking schedule (20% solutionfor 6 weeks) on energy balance and carbohydrate and lipid metabolismhave been investigated in lean (32–36 g) and obesediabetic(40–44 g) CBA/Ca mice. The untreated obesediabetic miceexhibited hyperglycaemia, hypertriglyceridaemia, hyper-insulinaemiaand insulin resistance. The chronic ethanol treatment, whichyielded plasma ethanol levels of between 1 and 11 mM, loweredthe blood glucose, plasma insulin and tnacylglycerol levelstowards normal in the obese mice, but did not affect these parametersin the lean mice. The body weight of the obese mice tended toreturn to normal during the 6-week drinking period, althoughtheir total energy intake (9.2–10.0 kJ/g/week, food plusethanol-denved calories) was almost double that of the leanmice (4.8–5.4 kJ/g/week). The blood glucose response toacute insulin injection, which was significantly reduced inthe obese mice, became indistinguishable from the response ofnormal mice after chronic ethanol treatment. Soleus muscle glycogensynthesis in both lean and obese mice was not significantlyaltered by ethanol drinking, but brown adipose tissue lipogenesiswas significantly increased (by 50%) in the obese mice. It isproposed that ethanol is acting chronically to restore insulinsensitivity in the obese diabetic mice at doses which have littleor no effect in normal lean animals. This action is exerted,at least in part, at the level of brown adipose tissue lipogenesis.  相似文献   
147.
The CD11b/CD18 leukocyte integrin molecule mediates diverse neutrophil adherence-related functions, including cell:cell and cell:extracellular matrix attachments. To study the individual role of this leukocyte integrin in cell adherence in hematopoietic cells, we expressed the CD11b/CD18 complex on the surface of K562 cells, a cell line derived from an individual with chronic myelogenous leukemia in blast crisis. We used an amphotrophic retroviral vector designated LCD18SN, harboring the complete coding sequence for the CD18 subunit, to transfer the CD18 cDNA into K562 cells and select stable cell lines. The CD11b subunit in the expression plasmid pREP4 was transfected into these K562/CD18 cells by electroporation and stable cell clones were selected. These K562 cells possessed RNA and intracellular protein for each subunit, and they expressed the CD11b/CD18 heterodimer on the cell surface. When CD11b/CD18 expressing K562 cells were stimulated with phorbol myristate acetate (50 ng/mL) for 24 to 48 hours, these K562 cells formed dense cell:cell aggregates. This homotypic aggregation required both activation of the CD11b/CD18 complex and the induction of the counter- receptor for CD11b/CD18 on the conjugate cell. This cell line will (1) enable the structure-function relationships between cell activation and homotypic adherence to be assessed, (2) provide the opportunity to identify accessory molecules required for activation of the CD11b/CD18 complex, and (3) facilitate the identification of novel ligands for the CD11b/CD18 complex.  相似文献   
148.
149.
Prior lateral patellar dislocation: MR imaging findings   总被引:4,自引:0,他引:4  
Lance  E; Deutsch  AL; Mink  JH 《Radiology》1993,189(3):905
  相似文献   
150.
报道一种新型结构的全固态乌头碱电化学检测器的研制及其在流动注射分析中的应用。采用流动注射分析法对川乌、草乌及其中成药(小活络丸)中剧毒成分(双酯型生物碱)进行了测试,方法简便快速,结果同光度法接近。本文还提出了电化学法研究乌头碱水解动力学原理。在pH 6.5,温度98℃的条件下测得乌头碱水解成苯甲酰乌头碱的速度常数为1.36×10~(-2)min~(-1)。  相似文献   
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