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11.
Using a plasma separator, it is possible to wash large volumes of whole blood free of plasma proteins in short periods. The novelty, however, is that the same apparatus can be used to reversibly hemolyze and reseal the red blood cells (RBCs) using hypotonic and hypertonic dialysates, respectively. This technique was assessed using the fluorescent exogenous agent uranin (fluorescein sodium). Results indicate that the encapsulation of the RBCs can be completed in under 2 h. The encapsulation efficiency of the RBCs was approximately 80% with a RBC recovery rate of 75%.  相似文献   
12.
Lipid peroxidation in the brain cortex, striatum, hippocampus, and hypothalamus of rats of the KLA and KHA lines which were distinguished by their strategies of adaptive behavior was investigated following emotional-painful stress. Significant long-term changes in lipid peroxidation were shown to occur in the brain. These had a phase character and depended on the behavioral characteristics of the animals. The investigated brain regions were characterized by different reactions of lipid peroxidation to the stress. The induced depressive-like states (on the 21st day after the stress) in rats of the KLA and KHA lines were distinguished by the largest changes in lipid peroxidation in the striatum and hypothalamus and in the striatum and hippocampus, respectively. One could conclude on the basis of these results that both identical and different mechanisms of formation and development of depression existed in the animals with different behavioral strategies.  相似文献   
13.
14.
穿心莲乙酯对大鼠心肌缺血再灌注损伤的保护作用   总被引:1,自引:0,他引:1  
本实验观察了穿心莲注射液对大鼠心肌缺血再灌注损伤的影响。结果显示:穿心莲(2.5mg·kg~(-1),iv)可保护缺血再灌注心肌SOD活性(P<0.01),降低MDA含量(P<0.001),明显降低严重心律失常发生率。提示穿心莲注射液对缺血再灌注心脏具有保护作用,其抗脂质过氧化作用可能系其作用机制之一。  相似文献   
15.
用四氧嘧啶诱导雄性Wistar大鼠为模型进行研究.结果发现,四氧嘧啶大鼠血糖明显升高,且心、肝、肾组织中过氧化氢酶活性较正常组明显降低,过氧化脂质含量在心、肝组织中明显增高,过氧化脂质与过氧化氢酶比值在心、肝、肾组织中均明显高于正常组,表明糖尿病状态下大鼠心、肝、肾组织中均自由基生成增多,氧化损伤加重.经六味地黄汤治疗后,血糖明显下降,但心、肝、肾组织中的过氧化氢酶活性无改变;而心肌中过氧化脂质含量和过氧化脂质与过氧化氢酶比值则明显降低,过氧化脂质含量和过氧化脂质与过氧化氢酶比值在肝、肾组织中无变化,表明六味地黄汤能明显清除心肌中自由基,抑制心肌中脂质过氧化,且此作用并不是通过提高过氧化氢酶活性来达到.  相似文献   
16.
Pharmacokinetics of prednisolone in children with the nephrotic syndrome   总被引:1,自引:0,他引:1  
The aim of this study was to establish whether the criteria for the clinical effectiveness of steroids are correlated with the pharmacokinetics of prednisolone in children treated with prednisone during an attack of idiopathic nephrotic syndrome (INS). Thirteen patients with nephrosis were included. Prednisolone, prednisone and cortisol levels were measured using a specific high-performance liquid chromatography assay after an oral dose of 1 mg/kg body weight of prednisone taken at the onset of the disease. All the pharmacokinetic parameters, including the conversion of prednisone to prednisolone were similar to the data already published in children with INS. No correlation was found between the values of pharmacokinetic parameters and criteria of clinical effectiveness. Hypo-albuminaemia was significantly correlated with the area under the plasma-concentration curve but not with the elimination half-life of prednisolone. Moreover, the prednisolone elimination half-life correlated with the urinary exretion of 17-hydroxycorticosteroids achieved in the first 6h. The present study suggests that routine measurements of prednisolone kinetics do not help when assessing the treatment of children with INS.  相似文献   
17.
对两组大鼠分别喂饲核黄素缺乏(RD)膳和核黄素添加(R8,22mg/kg饲料)膳8周后,测定了两组大鼠的红细胞维生素E(RBLVe)、红细胞超氧化物歧化酶(SOD)和红细胞丙二醛(MDA)的水平。结果发现:RD组RBCVe水平(4.7173±0.7710mg/g蛋白质)显著低于RS组(5。3868±1.1537mg/g蛋白质,P<0.05)。而RD组的RBCSOD(7745.2±610.1u/g蛋白质)和MDA(0.6868±0.1372μg/g蛋白质)则分别显著低于和高于RS组(8268.5±301.0nu/g蛋白质,0.5548±0.0980,P<0.05)。研究提示,核黄素缺乏引起细胞膜脂质过氧化加重可能RBCVe消耗增加。  相似文献   
18.
The cascade of physiologic mechanisms in response to infection, the acute-phase response, is recognized as playing a major role in host defence. One such response is the hypoferremia that is consistently reported to occur during bacterial infection. This study aimed to determine whether the alterations in plasma iron were conditionable using the conditioned taste aversion (CTA) paradigm. The regime involved the pairing of a novel-tasting saccharin solution with bacterial endotoxin. Seven days after the initial pairing of these stimuli (the test day), the saccharin solution was represented. Animals exposed to this condition displayed a significant reduction in the level of plasma iron. Animals treated with an intraperitoneal dose of 400 μg/Kg lipopolysaccharide (LPS) displayed lower conditioned iron levels than rats infused with 100 μg/Kg LPS; however, this difference was not significant. These results showed that in addition to other acute-phase responses (fever and anorexia), plasma iron alterations are able to be manipulated through behavioral manipulations.  相似文献   
19.
 Accurate, timed urine collections for the measurement of glomerular filtration rate (GFR) may be impractical in infants or in patients with urological abnormalities. GFR may be measured without urine collection using a constant subcutaneous infusion of iothalamate. We compare the infusion clearance with conventional renal clearance in 14 children and young adults. The mean clearance ratio (infusion clearance/renal clearance ± 1 SD) was 0.99±0.1 and the mean discrepancy between the two methods was 8.5%±4.7%. The 95% limits of agreement for the ratio of the two methods are 0.83–1.23. These data indicate that subcutaneous infusion of iothalamate is a practical method for measuring GFR in children without a urine collection. Received March 18, 1996; received in revised form February 12, 1997; accepted March 26, 1997  相似文献   
20.
In evaluating hypertensive children and adolescents, the etiological considerations should include a set of inherited disorders that share very low plasma renin activity (PRA) as a common feature. In particular among these disorders, glucocorticoid remediable aldosteronism (GRA) appears to be emerging as an important etiology of hypertension in the pediatric population. We report the evaluation of a 9-year-old Caucasian girl who presented with severe hypertension and a strong family history of early-onset hypertension. Her suppressed PRA, her family history, and her failure to respond to conventional antihypertensive therapy raised GRA as a potential etiology. The diagnosis was confirmed by an elevated ratio of urinary 18-oxotetrahydrocortisol to urinary tetrahydroaldosterone and genetic testing, which demonstrated the chimeric gene duplication. The molecular pathogenesis of GRA and the clinical implications are reviewed. Received May 15, 1996; received in revised form and accepted September 16, 1996  相似文献   
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