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目的:制备结合凝血酶原复合物(PCC)的阴离子脂膜微泡,评价微泡的理化性质。材料和方法:采用机械振荡直接连接法,分两组(于机械振荡之前或之后加入),制备结合PCC的阴离子脂膜微泡,观察并检测洗涤前后微泡的理化性质。结果:微泡与PCC的结合率及Ⅸ因子活性:两组间比较无明显差异(P>0.05),但洗涤后结合率由洗涤前的95%降为80%,活性由90%降为19%。结论:直接连接法可制备结合PCC的阴离子脂膜微泡,微泡与PCC结合率较高,且洗涤前能保持Ⅸ因子较高的活性。 相似文献
23.
Li-Peng Xu Wei-Jian Jiang Tao Ma Peng-Xin Qiu Jing Hou Yi-Jun Huang Jia-Shu Chen Guang-Mei Yan 《Toxicon》2006,47(2):241-248
A novel metalloproteinase, recombinant fibrinogenase IV (rFIV(a)), was expressed and purified from Deinakistrodon acutus venom. It was a single chain protein with an apparent molecular weight 27 kDa and an isoeletric point of pH 7.1. RFIV(a) cleaved preferentially the Aalpha-chain and also cleaved Bbeta, gamma-chains of fibrinogen when the incubation time was prolonged. The proteolytic activity was inhibited by EDTA, l-cysteine, and DTT, indicating rFIV(a) was a metalloproteinase requiring disulfide bonds for its activity. It kept above 85% of the initial activity from pH 4.5-11, showed an equal maximum activity at the temperature range from 30 to 50 degrees C, and was inactivated by Zn2+, Cu2+ and Cd2+. Homology modeling of rFIV(a) showed that two highly conserved disulfide bonds (Cys159-Cys164 and Cys117-Cys197) was maintained from its structure, and it exhibited the characteristic conserved motif H142E143XXH146XXGXXH152, whose three histidine residues were involved in binding of the catalytically essential zinc ion. This work demonstrates the expression, purification and characterization of recombinant fibrinogenase IV, which belongs to class P-I metalloproteinase from D. acutus venom. 相似文献
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通过溴化聚苯醚和格利雅试剂反应,将不饱和基团烯丙基引入聚苯醚中实现其热固性改性,由^1H-NMR和FTIR进行结构表征。确定了烯丙化聚苯醚的固化工艺,并对其固化产物性能进行测试。结果表明:按合成新工艺制备的热固性聚苯醚,其固化产物具有优异的介电性能(低介电常数、低介电损耗因子),良好的耐溶剂性能和低吸湿性。 相似文献
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测定了以葡萄糖酸内酯(GDL)作为凝固剂时不同热处理条件下大豆蛋白主要组分———7S和11S单独胶凝时的流变学曲线,证实了蛋白质的充分变性是GDL引发大豆蛋白胶凝的前提,且已充分热变性的7S和11S组分在单独胶凝时具有大致相当的凝胶强度.通过测定7S和11S组分的物理化学性质,解释了在以GDL作为凝固剂时两组分表现出基本相似的胶凝能力,与7S组分较高的疏水性和11S组分较高的巯基含量有关. 相似文献
26.
T. Ariga Y. Sakiyama K. Tomizawa S. Imajoh-Ohmi S. Kanegasaki S. Matsumoto 《European journal of pediatrics》1993,152(6):469-472
Molecular genetic analysis was performed in a patient with cytochrome b positive X-linked chronic granulomatous disease. A previous Southern blot study, using a cytochrome b heavy chain cDNA as probe, revealed a Pst I restriction fragment pattern for the cytochrome b heavy chain gene (CYBB) different to that of normal individuals. Since restriction length polymorphism with Pst I has never been observed in control individuals and no abnormal restriction fragment patterns in the patient's CYBB was detected with seven other enzymes used, we focussed on the single Pst I site in the CYBB cDNA as being the only mutation site responsible for his disease. A fragment of the patient's cDNA which included the Pst I site was amplified by reverse polymerase chain reaction, and loss of the Pst I site in the fragment was confirmed by incubation with Pst I. Subsequent sequence analysis of the fragment revealed a point mutation in the Pst I site (cytosine to adenine), substituting glutamic acid for alanine at position 57. 相似文献
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K. S. Us P. M. Klodt V. S. Kudrin A. Ya. Sapronova R. U. Ostrovskaya M. V. Ugryumov K. S. Rayevsky 《Neurochemical Journal》2007,1(2):138-142
The level of spontaneous and K+-stimulated release of endogenous glutamate was studied in experiments on slices of brain cortex of Wistar rats. Pronounced spontaneous release of the neuromediator and its increase under conditions of stimulation were registered by high-performance liquid chromatography with electrochemical detection. The effect of the nootropic and neuroprotective dipeptide Noopept (GVS-111) on release of glutamate was investigated. The peptide in concentrations of 10?5 and 10?6 M caused a statistically significant decrease in spontaneous and K+-stimulated glutamate release. This effect could be the basis of the neuroprotective action of the peptide, suggesting that further studies of Noopept as neuroprotector are very promising. 相似文献
30.
Summary We present a simple method for the isolation of DNA from agarose gels that is economic, fast, and independent of electrical equipment. DNA fragments of up to 6 kb can be easily extracted within 5 min using a disposable plastic syringe and filter paper. Total extraction of DNA fragments between 10 and 20 kb in size is achieved by concentrating the DNA flushed from the gel in a DNA-binding column. 相似文献