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71.
慢性乙肝患者NK,ADCC活性及其对IFN—α,IFN—γ的反应 总被引:1,自引:0,他引:1
本文用Hela细胞乳酸脱氢酶释放法测定了42例慢性乙肝病人外周血NK、ADCC活性及其对IFN-α100U/ml、500U/ml及IFN-γ500U/ml预处理4小时后的反应。结果显示,病人PBL NK,ADCC活性与正常对照有显著差别,经IFNs处理后,其NK或/和ADCC活性均有不同程度的升高反应,从而提示了IFNs在慢性肝病治疗中的重要作用。 相似文献
72.
空肠弯曲菌HSP43诱导自身免疫机理──分子模拟和抗原优势 总被引:3,自引:0,他引:3
我们曾发现空肠弯曲菌43kD热休克蛋白(HSP43)能诱导小鼠产生自身免疫应答,本文则进一步分析了这种诱导作用的机理。二株针对HSP60保守区序列的单克隆抗体IIH9和ML-30不但能结合人及小鼠细胞中HSP60家族成员,而且也能结合HSP43,表明HSP43、人及小鼠HSP60三者均属同一家族成员,具有序列上的高度同源性。小鼠用空肠弯曲菌免疫后出现了针对10种菌体蛋白的抗体,其中最早被诱导的抗体是针对HSP43的,并且该种抗体在随后80d观察期间内保持了较高活性,表明HSP43是优势抗原。本文结果提示,HSP43较易被免疫系统识别而产生应答,通过和宿主HSP60高度序列同源性而可能呈现分子模拟,从而诱导自身免疫损伤。 相似文献
73.
74.
作者在18只尸体手标本上,对拇指背动脉进行了显微解剖研究,发现该动脉出现率较恒定,起始部血管外径平均为0.63mm,动脉可解剖长度为7.2cm,血管分布范围包括第一掌骨背侧、部份鱼际区及拇指近节背桡侧5×10cm 的皮肤。以拇指背动脉及与其相连的桡动脉远段为蒂,可以游离成一个理想的岛状皮瓣,适用于拇指再造及邻近的组织缺损修复。 相似文献
75.
Lichtenwalter KG Apffel A Bai J Chakel JA Dai Y Hahnenberger KM Li L Hancock WS 《Journal of chromatography. B, Biomedical sciences and applications》2000,745(1):231-241
MALDI-TOF MS has potential as a valuable technique in DNA mapping studies and may well be complementary to other approaches to DNA analysis such as gel electrophoresis and sequencing. This study used 2,6-dihydroxyacetophenone (DHAP) mixed with diammonium hydrogen citrate (DAHC) as the matrix. In addition, recent technical advances such as time lag focussing (TLF) and better selection of matrices (such as 3-hydroxypicolinic acid (3 HPA) and picolinic acid (PA)) extended the range of DNA fragments that can be studied by this approach. The following samples were investigated: Poly-T mixture (dT 15, 19, 20, 25, 74 and 75), plasmid pBR322 derived oligonucleotides (10, 11, 12, 13, 14, 15, 19, 20 and 50 nucleotides long) and DNA fragments of 25, 36 and 37 base pairs corresponding to a fragment in the restriction map for the gene corresponding to the hexon protein of Adenovirus 2 and 5. The results were contrasted with similar analyses performed by ion-paired reversed-phase HPLC coupled to on-line electrospray mass spectrometry. 相似文献
76.
用抗CD59单抗2A7与CNBr-Sepharose4B偶联制备亲和层析柱,从正常人红细胞膜蛋白抽提物中分离纯化出CD59分子。本法纯化的CD59分子量为18-20KDa对还原剂敏感,与McAbssMEM43和1F5有高亲和性,再掺入豚鼠红细胞后,能够抑制人体补体的反应性溶血,本文还对三株抗CD59单抗2A7,MEM43及1F5的抗原特异性进行了初步分析。 相似文献
77.
Bai Y Ding Y Spencer S Lasky LA Bromberg JS 《Experimental and molecular pathology》2001,71(2):115-124
Prominent in T cells and natural killer cells, CD2 binding protein 1 (CD2BP1) plays an important role in CD2-mediated adhesion and signal transduction. In the current study, we investigated CD2 and PSTPIP (proline, serine, threonine phosphatase interacting protein, murine homologue of CD2BP1) interactions in purified mouse splenic T cells. PSTPIP associated with CD2 in both resting and activated T cells. Following various stimuli, such as concanavalin A, anti-TCRbeta, anti-CD3epsilon, anti-CD3epsilon/phorbol myristate acetate (PMA), IL-2, or PMA/ionomycin, PSTPIP and CD2 expression, as well as their association, increased in a time-dependent fashion. While PSTPIP expression and CD2 expression were comparable across most groups, the PSTPIP-CD2 association stimulated by anti-CD3epsilon alone was significantly greater than with other stimuli. Stimulation by anti-CD3epsilon plus anti-CD28 induced even greater PSTPIP-CD2 association than anti-CD3epsilon treatment alone, indicating that CD28 initiated signals are involved in regulating this interaction. There was no direct association between CD3epsilon or CD28 and PSTPIP. Tyrosine phosphorylated PSTPIP bound poorly to CD2 compared to dephosphorylated PSTPIP, and protein tyrosine phosphatase was shown to affect both phosphorylation of PSTPIP and the CD2-PSTPIP association. In addition to CD2, PSTPIP associated with CD4, CD8, CD54, and CD62L. CD2 and CD4 ligation reciprocally regulated their association with PSTPIP. These findings indicate that T cell activation, particularly through the CD3 and CD28 signal transduction pathways, regulates PSTPIP-CD2 interactions. PSTPIP likely has additional broader effects through interactions with CD4, CD8, CD54, and CD62L, and this may influence T cell responses to antigen. 相似文献
78.
Bai Y Zhao Y Yu T Dierich MP Chen YH 《International archives of allergy and immunology》2000,121(2):170-172
Based on our finding that a common epitope exists between HIV-1 gp41 and human type I interferons (IFN-alpha and IFN-beta), and increased levels of antibodies against human IFN-alpha and IFN-beta were observed in HIV-1-infected individuals, we tried to explain the mechanism of increased levels of antibodies. Mouse antisera recognizing HIV-1 recombinant soluble (rs) gp41 (aa 539-684) interacted with two synthetic peptides sequence-corresponding to the IFN-alpha/beta receptor binding site on human IFN-alpha and IFN-beta, while normal mouse serum (pooled normal sera) did not. The anti-rspg41 antisera after adsorption by IFN-beta sepharose column lost the activity of interaction with both synthetic peptides. In another experiment, rsgp41 could bind to sepharose column conjugated with anti-IFN-beta polyclonal antibodies (IgG). These results indicate that the common epitope on gp41 and type I interferons could induce antibodies recognizing the receptor binding site on IFN-alpha and IFN-beta, suggesting that increased levels of antibodies against IFN-alpha and IFN-beta in HIV-1-infected individuals could be induced by gp41. 相似文献
79.
Xiaqiong Wang Juan Cai Bolong Lin Ming Ma Ye Tao Yubo Zhou Li Bai Wei Jiang Rongbin Zhou 《Immunity》2021,54(6):1123-1136.e8
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80.
皮质—网状—脊髓通路——HRP法结合溃变电镜法研究 总被引:2,自引:1,他引:2
用HRP逆行标记法结合溃变电镜技术,观察了12只大鼠的蓝斑,外侧网状核,中缝大核,巨细胞网状核在旁正中网状核中皮质纤维终末的超微结构及其与网状脊髓神经元的突触联系。损伤皮质感觉运动区的各例动物,均出现两种溃变型,电子致密型和微丝增生型。前者为皮质的主要溃变型,分布于各核;后者出现很少,只见于外侧网状核。电子致密型终扣有大小两种,大终扣少,有含圆形清亮型小泡,多形清亮型小泡,清亮型和颗粒型小泡并存的 相似文献