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排序方式: 共有890条查询结果,搜索用时 15 毫秒
41.
本研究以前染蛋白为指示,将制备型SDS—PAGE和电渗析技术相结合,分离、纯化日本血吸虫和曼氏血吸虫成虫31/32kD蛋白,用于ELISA中诊断血吸虫病。结果:纯化日本血吸虫成虫31/32kD蛋白(Psj31/32)与急、慢性日本血吸虫病和曼氏血吸虫病人血清反应的阳性率分别为100%、100%和98.4%;纯化曼氏血吸虫成虫31/32kD蛋白(Psm31/32)与上述病人血清反应的阳性率均为100%。与NHS和其它寄生虫病人血清反应的特异性较高。Psj31/32和Psm31/32检测同种血清,它们的OD值具有高度的正相关关系,但OD值与曼氏血吸虫病人粪便中虫卵数量(EPG)无相关关系。结果提示:两种纯化的31/32kD蛋白在血吸虫病诊断中具有较高的敏感性和特异性,并具有共同抗原决定簇存在,不仅可用于诊断急、慢性日本血吸虫病,而且Psj31/32也可作为诊断曼氏血吸虫病的候选抗原,用于我国输入性曼氏血吸虫病的诊断。 相似文献
42.
目的探讨凝胶定量软件Quantity One用于血清差异蛋白质组学研究的可行性。方法运用凝胶成像系统中的定量软件Quantity One对各电泳图上的各条带进行定量分析,将图形结果转换为数据结果;用上述技术分别对健康体检者和肝癌病人各32份除高丰度蛋白的血清电泳图进行分析,验证该研究方法的可行性。结果两组间有10个条带差异具有统计学意义(P〈0.05)。通过文献检索,其中9条找到相对应分子量的HCC标志物。结论凝胶定量软件QuantityOne可量化处理电泳条带的分子量和灰度;一维凝胶电泳技术可用于血清差异蛋白初期比较研究。 相似文献
43.
Christine Schulze 《European journal of pharmaceutics and biopharmaceutics》2011,77(3):376-383
The alveolar lining fluid (ALF) covering the respiratory epithelium of the deep lung is the first biological barrier encountered by nanoparticles after inhalation. We here report for the first time significant differences for metal oxide nanoparticles to the binding of surfactant protein A (SP-A), the predominant protein component of ALF. SP-A is a physiologically most relevant protein and provides important biological signals. Also, it is involved in the lung’s immune defence, controlling e.g. particle binding, uptake or transcytosis by epithelial cells and macrophages. In our study, we could prove different particle-protein interaction for eight different nanoparticles, whereas particles of the same bulk material revealed different adsorption patterns. In contrast to other proteins as bovine serum albumin (BSA), SP-A does not seem to significantly deagglomerate large agglomerates of particles, indicating different adsorption mechanisms as in the well-investigated model protein BSA. These findings may have important consequences for biological fate and toxicological effects of inhaled nanomaterials. 相似文献
44.
Olinda Cabral da Silva Santos Marinella Silva LaportLúcia Martins Teixeira Marcia Giambiagi-deMarvalNatalia Lopes Pontes Iorio Kátia Regina Netto dos Santos 《Diagnostic microbiology and infectious disease》2009
We identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) 10 species and 5 subspecies of Staphylococcus among 139 clinical isolates and compared it with conventional tests. All isolates showed species-specific whole-cell protein profiles, even atypical strains, with up to 60% and at least 73.5% of interspecies and intraspecies similarity, respectively. Except for 5 isolates that presented biochemical profiles of Staphylococcus hominis subsp. hominis, but were identified as S. hominis subsp. novobiosepticus by SDS-PAGE, there was 100% accordance between the methods used. Comparison with the partial 16S-rDNA sequences confirmed by SDS-PAGE showed the high accuracy of this method to identify staphylococci subspecies and species. 相似文献
45.
Kaempferol induces apoptosis in human lung non-small carcinoma cells accompanied by an induction of antioxidant enzymes. 总被引:3,自引:1,他引:3
Henry W-C Leung C-J Lin M-J Hour W-H Yang M-Y Wang H-Z Lee 《Food and chemical toxicology》2007,45(10):2005-2013
Kaempferol (3, 4',5,7-tetrahydroxyflavone) is one of the most commonly found dietary flavonols. The biological and pharmacological effects of kaempferol may depend upon its behavior as either an antioxidant or a prooxidant. However, the clear biological effects of prooxidant or antioxidant character of kaempferol has not been clarified yet. The overall objective of the present study is to explore the role of prooxidant or antioxidant in kaempferol-induced cell toxicity. In this paper, we have proved that antioxidant pathway may be involved in kaempferol induces H460 cell apoptosis. Kaempferol-induced H460 cell apoptosis is a typical apoptosis that was accompanied by a significant DNA condensation and increasing intracellular ATP levels. Kaempferol-induced apoptosis is related to its ability to change the expression of apoptotic markers, such as caspase-3 (caspase-dependent) and AIF (caspase-independent). The overexpression of antioxidant enzyme Mn SOD protein levels, which was promoted to a new type tumor suppressor gene in several human cancer cells recently, may be an important role in kaempferol-induced H460 cell apoptosis. 相似文献
46.
目的探讨低温炮制工艺对地龙水溶性蛋白质组成以及溶栓与抗肿瘤活性的影响。方法地龙的炮制采用传统与低温两种工艺,低温炮制采用液氮快速冷冻与冷冻干燥技术;采用SDS-PAGE与ImageTool软件,对两种炮制工艺的地龙蛋白质组成的差异进行定性与定量分析;应用纤维蛋白平板法与体外溶栓试验,定性与定量分析两种炮制工艺的纤溶活性的差异;应用显微观察与MTT法,对两种炮制工艺体外抑制人肝癌细胞增殖活性进行定性与定量比较分析。结果低温炮制工艺地龙的水溶性蛋白组成比传统炮制工艺丰富,SDS-PAGE的蛋白条带数与浓度明显高于传统工艺;两种炮制工艺的地龙蛋白液均具有显著的抗人肝癌细胞与纤溶活性,但低温炮制工艺的两种活性显著高于传统工艺。结论不同炮制工艺对地龙水溶性蛋白组成及其抗肿瘤与溶栓活性有显著影响;在保全地龙的蛋白质类药效成分的生物活性方面,低温炮制工艺优于传统炮制工艺。 相似文献
47.
K J Nzoughet J T G Hamilton S D Floyd A Douglas J Nelson L Devine C T Elliott 《Toxicon》2008,51(7):1255-1263
The occurrence of azaspiracid (AZA) toxins in contaminated shellfish has been the focus of much research. The present study investigated the binding properties of these toxins in mussels of the species Mytilus edulis. The work involved extraction of proteins and AZAs from contaminated mussel hepatopancreas and examination of the extracts by isoelectric focusing (IEF), size exclusion chromatography (SEC) and sodium docecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Liquid chromatography coupled with tandem mass spectrometry analysis (LC-MS/MS) was also performed in this study to identify AZAs. Blank mussels were subjected to the same purification and analytical procedures. AZAs were found to be weakly bound to a protein with a molecular weight of 45 kDa, in samples of contaminated mussels. This protein, which was abundant in contaminated mussels, was also present in blank mussels, albeit at much lower concentrations. It was further noted that a 22 kDa protein was also present only in contaminated mussel samples. 相似文献
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50.
Trichomonas vaginalis avidly bound numerous host macromolecules which were not removed by repeated washing in phosphate buffered saline. The use of radioiodinated Cohn plasma fractions in binding studies allowed the identification of plasminogen, fibrinogen, immunoglobulin G, lipoproteins A and B, transferrin, α1-antitrypsin, and albumin on intact organisms. The binding of immunoglobulin G, albumin, transferrin, and lipoproteins to intact, motile trichomonads was further demonstrated using 125I-labeled plasma that was chromatographically depleted of these proteins. Kinetic studies indicated that 125I-labeled lipoproteins bind to T. vaginalis in a receptor-ligand-like manner. The surface localization and uptake of bound lipoproteins was shown by treatment of intact organisms with pronase at various times after incubation with lipoproteins. Purified lipoproteins could be substituted for plasma or serum as a growth supplement in a complex medium of trypticase/yeast extract/maltose and supported growth and multiplication rates equal to those in the same medium with plasma. 相似文献