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971.
白纹伊蚊和埃及伊蚊defensin A基因克隆及序列分析 总被引:5,自引:0,他引:5
应用PCR技术从白纹伊蚊和埃及伊蚊基因组中扩增出defensinA基因 ,并与文献报道的defensinA的5个型的cDNA序列进行同源性比较 ,发现此两序列中存在内元 ;从埃及伊蚊体内扩增的片段为蚊虫defen sinAl的前体AaDefAl;从白纹伊蚊体内扩增的片段为defensinA的 1个新型 ,命名为DefA6。 相似文献
972.
Stefano M Santini Tiziana Di Pucchio Caterina Lapenta Stefania Parlato Mariantonia Logozzi Filippo Belardelli 《Journal of interferon & cytokine research》2002,22(11):1071-1080
Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs) and thus play a pivotal role in induction of the immune response. Recent studies in both human and mouse models have shown that type I IFN, cytokines originally characterized for their antiviral activity and exerting multiple biologic effects, efficiently promote the differentiation and activation of DCs. These observations, together with the findings that DCs can express biologically relevant levels of type I interferon (IFN) and, in particular, that high amounts of these cytokines are released by specialized DC precursors (i.e., plasmacytoid DCs) in response to viral infections, strongly suggest the existence of a natural alliance between type I IFN and DCs, which is instrumental in ensuring an efficient immune response to both infectious agents and tumors. Further recent knowledge on the interactions between type I IFN and DCs emphasizes the importance of these cytokines in linking innate and adaptive immunity and may lead to new perspectives in their use as vaccine adjuvants as well as in strategies for the development of DC-based vaccines. 相似文献
973.
大鼠心冠状动脉系统神经肽Y年龄变化的免疫组织化学研究 总被引:3,自引:0,他引:3
运用免疫组化ABC法对不同月龄SD大鼠心脏冠状动脉及其分支含神经肽Y神经纤维的分布及其衰老变化作了详细观察.结果表明:左、右冠状动脉及其各级分支具有丰富的神经肽Y能神经分布.在冠状动脉主干及其较大分支上,神经纤维较稠密,主要呈环状或网状分布,在血管围周形成较多束、丛、网,并伸入血管壁内形成壁内的神经网络分布.部分神经纤维的游离末梢有穿过血管内膜伸向腔面的迹象.在细小的冠状动脉分支上,神经纤维密度减低,主要沿血管长袖是纵向分布.两侧冠状动脉系统神经肽Y能纤维分布形式及密度没有差别.老龄组动物,左、右冠状动脉及其分支的神经肽Y能纤维密度趋于下降,纤维变细,呈断续状,膨体数量减少,免疫染色变浅、此外,在心内发现了神经肽Y能神经节. 相似文献
974.
Victor M. Byrd Xiao Ming Zhao Geraldine G. Miller James W. Thomas 《Immunologic research》1994,13(2-3):139-144
The primary lesion in rheumatoid arthritis (RA) is a destructive synovitis characterized by proliferation of endothelial cells, fibroblasts, and vascular smooth muscle cells, and with perivascular lymphocyte aggregates. A nonhematopoietic growth factor, acidic fibroblast growth factor (aFGF), may induce many of the biological features found in rheumatoid synovium, including T cell activation. To determine if aFGF-responsive T cells are increased in RA, we developed an assay to measure the frequency of peripheral blood T cells that are costimulated by aFGF. The data indicate that the frequency of aFGF-responsive T cells is increased in RA and may change with disease activity and treatment. 相似文献
975.
磷酸盐型低密度脂蛋白亲和吸附剂制备与体外吸附试验研究 总被引:1,自引:0,他引:1
研究目的是制备低密度脂蛋白亲和吸附剂,用于去除高脂血症患者血液中高含量的低密度脂蛋白。首先以悬浮分散法制备壳聚糖微球和纤维素微球载体,然后固定磷酸吡哆醛和磷酸盐配基,制备出三种吸附剂,并进行体外静态吸附性能测试。结果表明,壳聚糖-磷酸吡哆醛吸附剂对LDL最大吸附量为1.30mg/mL,磷酸盐型壳聚糖和纤维素吸附剂对LDL的最大吸附量分别为2.72mg/mL和3.12mg/mL,并且吸附量随配基含量的增加呈增大趋势,3种吸附剂对高密度脂蛋白均无明显吸附。对吸附剂的灭菌和储存稳定性的研究表明,磷酸盐型纤维素吸附剂具有较好的稳定性。本研究第一次报道磷酸盐型低密度脂蛋白吸附剂。 相似文献
976.
目的:观察结核分枝杆菌培养滤液蛋白(Mycobacterium tuberculosis culture filtrate protein,CFP)对变应性鼻炎患者Th1和Th2失衡的影响。方法:抽取30例变应性鼻炎患者外周静脉血,分离单个核细胞(PBMCs),采用MTF法测定刺激淋巴细胞增殖最佳CFP浓度,采用酶联免疫吸附试验(ELISA)检测CFP干预前后PBMCs培养上清液中的白细胞介素4(IL-4)、白细胞介素5(IL-5)和干扰素γ(IFN-γ)水平。结果:变应性鼻炎患者组PBMCs上清液中IL-4、IL-5含量较正常对照组显著增高,而IFN-γ含量显著减少。CFP干预后变应性鼻炎患者组上清液IL-4、IL-5水平明显降低,而IFN-γ含量显著升高,差异有显著性。结论:CFP能纠正变应性鼻炎患者体内Th1和Th2细胞因子的失平衡状态,为治疗变应性鼻炎提供了理论依据。 相似文献
977.
Summary Basing our study on serial cuts and dissections, we have analysed the various techniques for puncture and injection in the region of the shoulder, the scapulohumeral and acromioclavicular joints, the subdeltoid bursa, the peri-articular muscles and tendons and the suprascapular nerve.
Bases anatomiques des ponctions et injections de l'épaule
Résumé A partir de coupes sériées et de dissections les auteurs étudient les différentes techniques de ponctions et injections pratiquées au niveau de la région de l'épaule, articulations scapulo-humérale et acromio-claviculaire, bourse sous-deltoïdienne, tendons des muscles péri-articulaires et nerf sus-scapulaire.相似文献
978.
Association of KIR Genotypes and Haplotypes with Susceptibility to Chronic Hepatitis B Virus Infection in Chinese Han Population 总被引:1,自引:0,他引:1
Zhiming Lu Bingchang Zhang Shijun Chen Zhongtao Gai Zhaolei Feng Xiangdong Liu Yiqing Liu Xin Wen Li Li Yulian Jiao Chunyan Ma Song Shao Xiangfa Cui Guojian Chen Jianfeng Li Yueran Zhao 《Cellular & molecular immunology》2008,5(6):457-463
Killer immunoglobulin-like receptor (KIR) genes can regulate the activation of NK and T cells upon interaction with HLA class I molecules. Hepatitis B virus (HBV) infection has been regarded as a multi-factorial disorder disease. Previous studies revealed that KIRs were involved in HCV and HIV infection or clearance. The aim of this study was to explore the possibility of the inheritance of KIR genotypes and haplotypes as a candidate for susceptibility to persistent HBV infection or HBV clearance. The sequence specific primer polymerase chain reaction (SSP-PCR) was employed to identify the KIR genes and pseudogenes in 150 chronic hepatitis B (CHB) patients, 251 spontaneously recovered (SR) controls, and 412 healthy controls. The frequencies of genotype G7 M, FZ1 increased in CHB patients compared with healthy control subjects. The frequency of genotype AH was higher in SR controls than that in both CHB patients and healthy controls. The carriage frequencies of genotype G and AH were higher; while, the frequencies of AF and AJ were lower in SR controls than those in healthy control subjects. The frequency of A haplotype was lower, whereas, the frequency of B haplotype was higher in CHB patients and SR controls than those in healthy controls. In healthy controls, haplotype 4 was found lower compared with that in CHB patients and SR controls and the frequency of haplotype 5 was higher in SR controls than that in other two groups. Based on these findings, it seems that the genotypes M and FZ1 are HBV susceptive genotypes; AH, on the other hand, may be protective genotypes that facilitate the clearance of HBV. It appears that the haplotype 4 is HBV susceptive haplotype, whereas, haplotype 5 may be the protective haplotype that facilitates the clearance of HBV. Cellular & Molecular Immunology. 2008;5(6):457-463. 相似文献
979.
Vacatello M D'Auria G Falcigno L Dettin M Gambaretto R Di Bello C Paolillo L 《Biomaterials》2005,26(16):3207-3214
A properly engineered biomaterial for dental/orthopaedic applications must induce specific responses from the osteoblasts at the implant site. A most desirable response is an efficient adhesion, as it represents the first phase in the cell/material interaction and the quality of this phase will influence the cell's capacity to organize into a new functional tissue. The four osteoblast-adhesive peptides discussed in this paper are mapped on the 339-364 sequence (339MAPRPSLAKKQRFRHRNRKGYRSQRG364) located in the primary heparin-binding site of human vitronectin (HVP). Adsorbed on a polystyrene scaffold, these peptides display different adhesive activities towards osteoblasts. In this paper we report on the structural analysis in solution of the peptides through NMR and computational techniques. We find that the peptides with the highest adhesive activities display a hydrophobic patch opposite to the charged surface candidate to interact with heparin. These findings suggest that the peptides might adsorb on the polystyrene support in a favourable orientation for their activity. Furthermore, molecular models obtained for the four peptides in solution were used in rigid docking simulations with a heparin model. Assuming that the peptide solution conformations are not very different from the polystyrene-adsorbed structures, the simulations reveal that peptide adhesive activity is also affected by the number of ionic interactions and spacing between charged residues. 相似文献
980.