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11.
生姜对超氧阴离子及羟自由基的清除作用   总被引:18,自引:2,他引:16  
生姜对次黄嘌呤-黄嘌呤氧化酶体系产生的超氧阴离子及紫外线照射H2O2体系产生的羟自由基均有显著清除作用。提示生姜对活性氧的清除可能是其重要的药理机制之一。  相似文献   
12.
目的 进一步了解肝癌患者的异常免疫状态,探讨血清、腹水中可溶性肿瘤坏死因子受体-p55(sTNFR-p55)检测的临床意义。方法 以双单抗夹心酶免疫吸附法检测了25例肝癌患者和25例肝硬化患者的血清、腹水中血清sTNFR-p55水平并以正常人为对照。结果肝癌病人血清sTNFR-p55浓度[(0.74±0.50)ng/ml]显著高于正常人[(0.37±0.03)ng/ml]和肝硬化患者和[(0.35±0.02)ng/ml],P<0.01。肝癌病人腹水sTNFR-p55浓度[(1.11±1.25)ng/ml]亦显著高于肝硬化患者[(0.33±0.03)ng/ml],P<0.01。肝癌、肝硬化患者血清与腹水的sTNFR-p55水平显著相关。肝癌患者血清sTNFR-p55水平与外周血TBil和AFP呈正相关(r=0.524,P=0.01和r=0.234,P=0.03)。结论 sTNFR-p55的检测对反映肝癌患者的异常免疫状态和肿瘤诊断具有实用价值。  相似文献   
13.
96名镍作业工人测定结果:非特异酯酶阳性细胞百分率(ANAE+%)为76.8%±8.0%,T细胞亚群CD2、CD4、CD8阳性细胞百分率(CD+2%、CD+4%、CD+8%)及CD+4/CD+8比值分别为65.6%±10.5%、56.3%±12.1%、34.3%±8.2%和1.76±0.6;酵母多糖刺激的外周血多形核白细胞化学发光(PMN-CL)本底和峰值分别为48±23和3073±684CPS/106PMN;血清硒和丙二醛含量分别为1.22±0.23和4.76±0.88μmol/L。与非镍作业的地区对照组比较,T细胞CD+8%增高,CD+4/CD+8比值下降,化学发光的本底值降低,峰值增加,血清Se含量下降,丙二醛含量升高。分析镍作业工人工龄与后三项指标变化的关系,工龄大于20年与小于10年有统计学上明显差别。这些观察指标为镍作业人员医学观察增加新的监护指标提供依据。  相似文献   
14.
We have developed a sensitive enzymatic-immunoassay to quantify the level of gamma-enolase (a specific neuronal enzyme) which is released from cultured cells after exposure to various toxins. We show that this method can estimate selectively neuronal cell death without significantly interfering with glial cell death. Indeed, no gamma-enolase is released when glial cells are killed with free-radical producing agents. Experiments comparing the levels of neuronal cell death induced by NMDA or free-radical producing drugs, performed either by measuring gamma-enolase release or using the classical fluorescein diacetate method, yielded similar results. In addition to selectively follow neuronal death in a mixed population of neurons and glial cells, this method provides a way of determining the cell death kinetics from a single culture dish, since enolase can be measured on small samples taken from the culture medium. Finally, we propose these two methods as being complementary and useful neuronal and other cellular death indexes and also to understand the complex problem of glial influence on neuronal survival or death.  相似文献   
15.
作者以ABEI-CoCl_2-H_2O_2作为化学发光指示系统,用固相竞争法检测58例白细胞减少症患者、41例无白细胞减少症患者及32例正常人等的粒细胞抗体IgG。判断标准采用正常人血清化学发光强度指数法。实验结果表明,白细胞减少症患者血清中粒细胞抗体阳性率明显高于无白细胞减少症患者(P<0.005)。本法敏感性为43.1%,特异性为90.2%,准确性为62.6%,是一种灵敏而准确的方法,能将粒细胞包被试管在室温下较长时间保存,以供临床监测粒细胞抗体,大大缩短检测时间。  相似文献   
16.
电化学发光免疫分析法测定血清胰岛素效果评价   总被引:5,自引:0,他引:5  
①目的 探讨电化学发光免疫分析 (ECLIA)法测定血清胰岛素的效果及临床应用价值。②方法采用ECLIA法和放射免疫分析 (RIA)法分别测定糖尿病病人的血清胰岛素含量 ,并用酶联免疫法 (ELISA)测定C 肽含量 ,并对测定结果进行分析比较。③结果 ECLIA法测定胰岛素的批内与批间变异系数分别为 1.97% ,2 .5 6 % ,平均回收率是 99.5 % ;RIA法的批内与批间变异系数分别为 10 .18% ,13.2 1% ,平均回收率是 93.4 % ;E CLIA及RIA法所测胰岛素含量与ELISA法所测C 肽含量均呈正相关 (r =0 .94 ,0 .91,P均 <0 .0 1)。④结论ECLIA法测胰岛素的各技术参数优于RIA法 ,该方法能较好评价胰岛B细胞功能 ,且操作简便 ,检测速度快 ,具有重要临床应用价值。  相似文献   
17.
Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml-1 and 244 to 3,906 pg ml-1, respectively.  相似文献   
18.
A competitive enzyme immunoassay of histamine in foodstuffs has been developed using a monoclonal antibody against a histamine‐benzoquinone adduct. In this assay, histamine present in food samples was treated with 1,4‐benzoquinone to form histamine‐benzoquinone by a simple and quick reaction and a histamine‐benzoquinone‐horse‐radish peroxidase conjugate was used as the labelled hapten. The apparent association constant (Ka) of the antibody used was 3.6 ×106 l/mol and Gibbs’ energy of the immune complex formation has been estimated to find the optimal incubation time of the assay. The method enabled determination of histamine in fish, cheese, wine and beer at a concentration as low as 7 ng/ml with an accuracy of ± 15%. The recovery of the immunoassay was 88.9–114%. Cross‐reactivities of histidine, tyramine, tryptamine and its derivatives were lower than 0.001% and did not affect the assay.  相似文献   
19.
The effects of combined use of earthworm extract(912)and HpD-laser on the produc-tion of reactive oxygen and the biosynthesis of DNA in S_(180) tumor cells were studied throughchemiluminescence measurement and[~3H]-TdR incorporation assay.The results showed that as com-pared with the control,the intensity of chemiluminescence emitted by tumor cells treatedsimultaneously with 912 and HpD-laser was enhanced more than ten-folds,while that treated with912 or HpD-laser alone was increased only 2~4 folds.The[~3H]-TdR incorporation into tumorcells of the former group was inhibited upto 74.1%,and that of the latter groups decreased onlyby 42.2% and 40.0%,respectively.In accordance with these biochemical changes,the ultrastructuraldamage of tumor cells of the former,combinedly treated group appeared to be the most serious.This suggests an additive effect of 912 with HpD-laser on tumor cells.In addition,if free radicalscavengers,such as catalase and superoxide dismutase,were added to the reaction systembefore chemiluminescence assay,the luminescent enhancement effect mentioned above was dramaticallyalleviated,implying the presence of O_2~ and H_2O_2 in the system.Therefore,as to the toxic effecton tumor cells,912 and HpD-laser are not only additive in efficiency,but also similar in theunderlying mechanism of action.  相似文献   
20.
Ulrike Haun  Prof.  R. Rüchel  A. Spies 《Mycoses》1987,30(10):472-482
Summary: We describe a series of six serological tests for the diagnosis of deep-seated candidosis. The array comprises two commercial tests (antigen test, Ramco Inc., and antibody test, Roche), as well as four enzyme immunoassays which have been developed in this laboratory: an antigen test for detection of Candida-proteinase, the corresponding assays for monitoring of anti-proteinase antibodies, and two assays for monitoring of IgG and IgM against heterogenous metabolic antigens of C. albicans. The highly sensitive and specific proteinase antigen-test tolerates samples with high concentration of serum proteins. Proteinase antigen was detected in 10 out of 11 normal mice after intravenous infection with C. albicans blastospores. The proteinase antigen peaked between the second and fourth day after infection. A rise in corresponding antibodies was observed in all animals. No proteinase antigen was detected in sera of healthy human individuals; anti-proteinase antibody titers in these sera amounted up to 1:8000. In related ELISAs, using metabolic fungal antigens, titer values of specific IgG and IgM amounted to 5120 and 1280, respectively. The six tests were carried out in an comparative study under diagnostic conditions, the results of which are the subject of a forthcoming communication. Zusammenfassung: Ein Satz von sechs serologischen Tests für die Diagnostik der tiefen Candida-Mykosen wird vorgestellt. Die Gruppe schließt zwei kommerziell vertriebene Testbestecke ein (Latex-Agglutinationstest zum Antigennachweis, Ramco Inc., und Hämagglutinationstest zum Antikörpernachweis, Roche). Vier weitere Enzymimmuntests wurden von uns entwickelt: Ein Antigentest zum Nachweis von sekretorischer Candida-Protease, ein entsprechender Test zum Nachweis von Antikörpem gegen Candida-Protease, und zwei Assays zum Nachweis von IgG-bzw. IgM-Antikörpem gegen heterogene metabolische Antigene von C. albicans. Der empfindliche spezifische Protease-Antigentest toleriert hohe Konzentrationen unspezifischer Serumproteine und kann deshalb auf Serumproben in geringer Verdünnung (z. B. 1:20) angewandt werden. Protease-Antigen war in 200 fach verdünnten Seren von 10 aus 11 intravenös infizierten NWNI-Mäusen nachweisbar. Die höchste Antigen-Konzentration trat zwischen dem 2. und 4. Tag nach Infektion auf; die Serum-Halbwertszeit von gereinigter Protease in der Maus betrug etwa 60 nun. Ein Anstieg korrespondierender Antikörper war in alien infizierten Tieren zu beobachten. Auch im Serum gesunder Probanden waren Antiprotease-Antikörper bis zu einem Titer von 1:8000 nachweisbar; der Protease-Antigentest fiel hingegen immer negativ aus. Die Titer von Antikörpern gegen metabolische Candida-Antigene erreichten in derselben Gruppe von Seren Werte von 1:5120 bzw. 1:1280. Die sechs Tests wurden unter diagnostischen Bedingungen verglichen; Ergebnisse dieser Studie sind Gegenstand einer weiteren Mitteilung.  相似文献   
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