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61.
目的:探讨了冠心病患者治疗前后血清SOD、ET及T淋巴细胞亚群水平。方法:分别应用放免法和单克隆抗体法对42例冠心病患者进行了血清SOD、ET及T淋巴细胞亚群水平检测,并与35名正常健康人作比较。结果:冠心病患者在治疗前血清ET水平显著地高于正常人组(P<0.01),而SOD和CD4/CD8比值明显地低于正常人组(P<0.01),经治疗后一个月则与正常人组比较差异无显著性(P>0.05)。结论:检测冠心病患者血清SOD、ET及T淋巴细胞亚群水平对判断病情及其预后均具有一定的临床实用价值。  相似文献   
62.
Conventional indirect haemagglutination test was performed in rhesus monkey sera (collected from Plasmodium knowlesi infected animals) with and without prior treatment of sera with 2-mercapto-ethanol (2-ME). Surprisingly, many sera samples showed significant enhancement of final titre with 2-ME. The 2-ME enhancement effect was more pronounced in the sera of hyperimmune monkeys on further injection of antigen or parasites. It was also noticeable in the sera during primary drug-suppressed P. knowlesi infection and appeared to have a bearing on the immune status of the animals to rechallenge. The use of a soluble antigen prepared from P. knowlesi infected erythrocytes was found to be essential in IHA test to demonstrate the 2-ME enhancement effect. Antigen prepared from freed parasites (commonly used) failed to show a similar effect in IHA. The possible role of certain T-lymphocyte products - antigen binding, non-agglutinating, 2-ME sensitive molecules - in malarial immunology has been proposed.  相似文献   
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Macrophages are known to release reactive oxygen species (O2?, 1O2, H2O2, OH·) in response to various membrane stimuliHowever, our studies show that phagocytic stimulation of macrophages is not necessarily accompanied by a stimulation of the oxidative burstWhereas IgG-opsonized erythrocytes were capable to induce phagocytosis and a chemiluminescence response, both being dependent on the number of IgG bound per erythrocyte, C3b-bearing erythrocytes were well ingested but failed to induce any chemiluminescence reactionFurthermore, stimulation of macrophages, via the Fc-receptors, seems to alter their functional state in regard to the activation of a receptor, which enables them to recognize membrane lesions on the target erythrocyteThe presence of IgG and membrane lesions, e.gthe C5b-9-complex of complement, induced a marked increase in chemiluminescence compared with stimulation by IgG-bearing particles aloneThe augmented response of macrophages was at least in part due to an additional release of H2O2, which was not liberated in response to IgG-bearing erythrocytesThis «Alesion recognizing receptor» in the macrophage membrane could not be activated by stimulation of C3b-receptors, indicating its functional linkage to the Fc-receptors.  相似文献   
66.
In order to study the characteristic of contraluminal transport of hydrophylic small fatty acids the in situ stopped flow microperfusion technique [12] has been applied. By measuring with 4 s contact time the decrease in the contraluminal concentration of the respective radiolabelled substances the concentration dependence of the influx into the cortical cells was tested. The 4 s decrease in contraluminal concentration of chloroacetate,l-lactate,d-lactate, 3-hydroxybutyrate and acetoacetate was between 26% and 31%. For each substance the percent decrease was the same, no matter whether it was offered in a concentration of 0.1 or 10 mmol/l. Contraluminal disappearance of 0.1 mmol/ll-lactate was not influenced by 5 mmol/l H2DIDS, probenecid, phloretin, mersalyl or cyanocinnamate, but it was significantly (37%) inhibited by 5-nitro-2-(phenyl-propyl-amino) benzoate, a blocker of the nonspecific anion channel. The percent decrease in propionate uptake was somewhat larger — between 36% and 39% — but again not different at 0.01, 0.1, 1.0 and 10 mmol/l. With pyruvate the contraluminal decrease was 20% at 0.1 mmol/l and 31% at 10 mmol/l. The percent disappearance of the aromatic pyrazinoate was 38% and 34% at 0.1 and 10 mmol/l and for nicotinate 42% and 22%, respectively. The disappearance of nicotinate (0.1 mmol/l) was significantly inhibited by 10 mmol/l pyrazinoate and paraaminohippurate (PAH). The data are in agreement with the hypothesis that the hydrophilic small fatty acids traverse the contraluminal cell side by simple diffusion, possibly via the unspecific anion channel [14], pyruvate via the dicarboxylic acid pathway in a cooperative manner and pyrazinoate, as well as nicotinate, via the PAH pathway.  相似文献   
67.
The enzyme responsible for the respiratory burst in human neutrophils is an oxidase that catalyzes the reduction of oxygen to superoxide anion (O-2). Superoxide anion production may be measured by chemiluminescence (CL) in the presence of lucigenin (10,10'-dimethyl-9,9'- biacridinium dinitrate). We established an assay of the oxidase, by measuring the CL of particulate fractions of PMN in the presence of lucigenin . This CL required the addition of NAD(P)H and was very low in fractions of resting cells. In particulate fractions of PMNs stimulated with PMA selectively, the NADPH-dependent CL was found to be increased. CL was linear with protein concentrations up to 100 micrograms and was shown to be at least 10 times more sensitive for the detection of O-2 than the assay based on the spectrophotometric determination of superoxide mediated cytochrome c reduction. CL was abolished by inactivating the enzyme at 56 degrees C.  相似文献   
68.
目的 :研究葡萄籽提取物对四氯化碳 (CCl4 )引起的脂质过氧化反应和抗氧化能力的影响。方法 :通过对大鼠的体内实验 ,测定大鼠肝和脑组织中由 CCl4 诱导产生的过氧化脂质生成物丙二醛(MDA) (TBA法 )的含量、血清中的超氧化物歧化酶 (SOD) (比色法 )活性和血清中总抗氧化能力(T- AOC) (比色法 )。结果 :葡萄籽提取物可明显降低大鼠肝和脑组织中 MDA的生成量 ,明显升高血清中 SOD活性和 T- AOC。结论 :葡萄籽提取物具有明显的抗氧化作用。  相似文献   
69.
一氧化氮及相关物质在卵巢肿瘤组织中的检测   总被引:1,自引:0,他引:1  
目的探讨一氧化氮(nitricoxide,NO)及其代谢中的相关物质谷胱甘肽(glutathione,GSH)的含量及超氧化物歧化酶(superoxidedismutase,SOD)的活性在卵巢肿瘤组织中的变化。方法应用改良的镀铜镉还原法测定NO  相似文献   
70.
目的:研究3-磷酸甘油醛脱氢酶的修饰蛋白(modifier protein,MP)对急性肾功能衰竭(acute renal failure,ARF)大鼠丙二醛(malondialdehyde,MDA)和超氧化物岐化酶(superxide dismutase,SOD)的影响。方法:利用庆大霉素致ARF的动物模型,将大鼠随机分成4组:正常对照组、阴性对照组、阳性对照组和实验组,采用硫代巴比妥酸法和羟胺法分别测定血清及肾皮质匀浆MDA和SOD,光镜、电镜观察肾组织学改变,同时测定血肌酐(Scr)。结果:实验组、阳性对照组血清及肾皮质匀浆MDA明显下降,SOD明显上升,P<0.01。同时Sct下降。光镜、电镜示实验组、阳性对照组肾脏病理仅呈灶状改变。比阴性对照组减轻。结论:MP可以缓解氧自由基损伤,减轻ARF时的肾脏病理改变,改善肾功能。  相似文献   
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