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991.
Yu. V. Pakin 《Bulletin of experimental biology and medicine》1977,83(4):555-557
The effect of the cultivation temperature on blast transformation of lymphocytes from persons aged 20–35 and 90–102 years induced by phytohemagglutinin was studied. Cultivation at 39°C was found to increase, but at 41°C to reduce sharply the index of blast transformation compared with the control (37°C). The effect of cultivation temperature on the blast-transformation process has certain features which depend on the donors' age.Institute of Gerontology, Academy of Medical Sciences of the USSR, Kiev. (Presented by Academician of the Academy of Medical Sciences of the USSR D. F. Chebotarev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 470–472, April, 1977. 相似文献
992.
比较Ⅰ型胶原与胞外基质(extracellularmatrix,EM)提取物冻干后形成的膜(EM膜)在体外构建人工真皮的能力,以选择一种更有利于人工真皮形成的支架材料。方法分别使用小牛真皮部分提取的Ⅰ型胶原蛋白和胞外基质提取物冻干后制备基质网架,植入皮肤成纤维细胞,形成人工真皮。用扫描电镜观察I型胶原膜和EM膜的表面形态结构;选取不同的时间点,对种植于两种支架材料上的细胞进行计数,并利用间接ELISA方法检测人工真皮复合物中的细胞Ⅰ型胶原分泌情况,通过统计学的分析手段,对细胞的生长情况做出判断;用组织学方法观察人工真皮的形成情况。结果扫描电镜观察结果,两种膜在外观形态上无明显差异;细胞在EM膜上的增殖速度较Ⅰ型胶原膜快;ELISA分析显示,EM-细胞复合物中的成纤维细胞能够分泌更多的Ⅰ型胶原;与Ⅰ型胶原膜相比,EM在培养液中的降解更为缓慢,种植后的成纤维细胞在EM膜上生长旺盛,细胞层次明显多于前者,形成了较为明显的真皮样组织。结论EM膜适于成纤维细胞的生长,体外降解速率慢,是一种较Ⅰ型胶原膜更为理想的真皮支架材料。 相似文献
993.
Inzhevatkin EV Fomenko EY Slepov EV Savchenko AA 《Bulletin of experimental biology and medicine》2004,138(5):497-500
The pattern of metabolic processes in lymphocytes of mice with Ehrlich ascites carcinoma depended on the stage of tumor growth.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 11, pp. 563–566, November, 2004 相似文献
994.
Ichikawa T Kitajima S Liang J Koike T Wang X Sun H Okazaki M Morimoto M Shikama H Watanabe T Yamada N Fan J 《Laboratory investigation; a journal of technical methods and pathology》2004,84(6):715-726
Lipoprotein lipase (LPL) is a key enzyme in the hydrolysis of triglyceride-rich lipoproteins. Previous studies using transgenic mice and rabbits have demonstrated that high level of LPL activity in adipose and skeletal muscle protects against diet-induced hypercholesterolemia and subsequently prevents aortic atherosclerosis. However, it is unknown, per se, whether increased LPL activity itself is antiatherogenic, or whether the antiatherogenic effect of LPL is dependent upon the LPL lipid-lowering effect. To address this issue, we fed LPL transgenic and littermate rabbits diets containing different amounts of cholesterol (0.3-0.6%) adjusted to maintain their plasma cholesterol concentrations at similarly high levels for 16 weeks. We analyzed their lipoprotein profiles and compared their susceptibility to atherosclerosis. The results showed that the overexpression of LPL in transgenic rabbits reduced remnant lipoproteins (beta-VLDL, d<1.006 g/ml) but concomitantly led to a significant increase of the large (d=1.02-1.04 g/ml) and small LDLs (d=1.04-1.06 g/ml) compared to the amounts in control rabbits. Furthermore, we found that with equally high hypercholesterolemia, transgenic rabbits developed 1.8-fold more extensive aortic atherosclerosis than control rabbits. To examine the hypothesis that altered lipoprotein profiles may be responsible for the enhanced atherosclerosis in transgenic rabbits, we studied the atherogenic properties of apoB-containing lipoproteins in vitro. These studies revealed that small-sized LDLs of transgenic rabbits were more susceptible to copper-induced oxidation and had higher affinity to biglycan than large remnant lipoproteins. We conclude, therefore, that LPL exerts a dual function in terms of its atherogenicity, namely antiatherogenicity, through enhancing receptor-mediated remnant lipoprotein catabolism and proatherogenicity via the generation of a large amount of small-sized LDLs. At an equal atherogenic-cholesterol level, small and dense LDLs are more atherogenic than large remnant lipoproteins. 相似文献
995.
支气管哮喘病人焦虑与生命质量的相关性研究 总被引:3,自引:0,他引:3
目的 评估支气管哮喘病人焦虑与生命质量的水平 ;探讨支气管哮喘病人焦虑与生命质量的关系 .方法应用状态 -特质焦虑问卷 (STAIFORMY)和世界卫生组织生命质量量表简表 (WHOQOL -BREF) ,分别对支气管哮喘门诊病人和健康对照人群的焦虑和生命质量水平进行问卷调查 .结果 哮喘组状态焦虑为 45 1± 9 7,特质焦虑为46 5± 9 7,生命质量为 87 3± 13 2 ;健康组的状态焦虑为 3 7 7± 7 4,特质焦虑为 3 8 4± 8 1,生命质量为 95 4± 11 7.哮喘组状态焦虑、特质焦虑与生命质量均负相关 ,相关系数分别为 - 0 69和 - 0 79.结论 ①支气管哮喘病人的状态焦虑及特质焦虑水平均高于健康人群 ,生命质量水平低于健康人群 ;②支气管喘病人的焦虑与生命质量负相关 .因此 ,在护理实践中应对哮喘病人进行焦虑的心理护理 ,提高其生命质量 相似文献
996.
下胫腓联合分离内固定术式的生物力学研究 总被引:2,自引:0,他引:2
目的 探讨下胫腓联合分离采用新型内固定术式———下胫腓钩板固定器 (Hook -platefixation ,HPF)的生物力学特性 ,与螺钉、钢板和带钩固定器三种内固定方式比较 ,为临床提供科学依据。方法 采用新鲜成人尸体足标本 6具 ,运用生物力学实验应力分析方法和压敏片技术 ,测量不同内固定术式的远端胫腓骨强度、应变、负重面积、接触应力和足弓承载能力及踝关节稳定性的变化。结果 新型下胫腓钩板固定器内固定术式无论在胫腓骨强度和刚度、负重面积、接触压力、足弓的变形、移位强度和刚度、承载能力以及踝关节的稳定性方面均优于其它三种内固定术式 ,具有显著性差异 (P <0 .0 1)。结论 实验结果表明 ,采用下胫腓钩板固定器 (HPF) ,既有利于提高生物力学性能 ,又有利于改善踝关节的稳定性 ,与传统手术方式相比可减少一次手术 ,避免了断钉等并发症 ,且能有效地提高足部承载能力 ,是下胫腓联合分离内固定的一种优良术式 相似文献
997.
A new type of continuous, supermacroporous, monolithic, cryogel affinity adsorbent was developed, allowing specific fractionation and separation of human peripheral blood lymphocytes in a chromatographic format. The affinity adsorbent was used to design a novel cell separation strategy, which was based on the interaction of protein A from Staphylococcus aureus with cells bearing IgG antibodies on the surface. After treating lymphocytes with goat anti-human IgG(H+L), the IgG-positive B-lymphocytes were efficiently separated from T-lymphocytes. Protein A covalently coupled to epoxy activated dimethylacrylamide (DMAA) cryogel matrix specifically bound IgG-bearing B-lymphocytes through the Fc region, while non-bound T-lymphocytes passed through the column. More than 90% of the B-lymphocytes were retained in the column while the cells in the breakthrough fraction were enriched in T-lymphocytes (81%). The viability of the T-lymphocytes isolated was greater than 90%. The bound lymphocytes released by human or dog IgG recovered 60-70% of the B-cells without significantly impairing the cell viability. The technique can be applied in general to cell separation systems where IgG antibodies against specific cell surface markers are available. 相似文献
998.
目的应用生物信息学方法预测B族链球菌C5a肽酶蛋白表位,结合基因工程手段进行表位重组、表达和免疫原性分析。方法用预测程序ProPred和ANTIGENIC预测B族链球菌C5a肽酶蛋白的表位,应用PCR技术扩增出编码该表位基因片段,克隆PCR产物构建重组质粒,测序验证。在大肠杆菌BL21(DE3)中诱导表达融合蛋白。表达的蛋白经质谱分析和Western blot鉴定。纯化该融合蛋白并免疫C57/BL小鼠,萃取GBS表面蛋白,双向琼脂扩散试验检测抗体水平。结果在SCPB中预测到1个既具有MHC结合肽特性又具有B细胞表位特征的肽段。重组和表达了这一肽段,质谱得出与SCPB蛋白的相似性分数为79,Western-blot证实能与抗SCPB的抗体反应,纯化后融合蛋白纯度〉90%。动物实验证实融合蛋白能产生特异性的抗GBS抗体。结论重组表位具有一定免疫原性。为相关蛋白的毒力机制研究和亚单位疫苗等方面的研究打下了良好的基础。 相似文献
999.
Protective efficacy in chickens, geese and ducks of an H5N1-inactivated vaccine developed by reverse genetics 总被引:18,自引:0,他引:18
We generated a high-growth H5N1/PR8 virus by plasmid-based reverse genetics. The virulence associated multiple basic amino acids of the HA gene were removed, and the resulting virus is attenuated for chickens and chicken eggs. A formalin-inactivated oil-emulsion vaccine was prepared from this virus. When SPF chickens were inoculated with 0.3 ml of the vaccine, the hemagglutinin-inhibition (HI) antibody became detectable at 1 week post-vaccination (p.v.) and reached a peak of 10log2 at 6 weeks p.v. then slowly declined to 4log2 at 43 weeks p.v. Challenge studies performed at 2, 3 and 43 weeks p.v. indicated that all of the chickens were completely protected from disease signs and death. Ducks and geese were completely protected from highly pathogenic H5N1 virus challenge 3 weeks p.v. The duration of protective immunity in ducks and geese was investigated by detecting the HI antibody of the field vaccinated birds, and the results indicated that 3 doses of the vaccine inoculation in geese could induce a 34 weeks protection, while 2 doses induced more than 52 weeks protection in ducks. We first reported that an oil-emulsion inactivated vaccine derived from a high-growth H5N1 vaccine induced approximately 10 months of protective immunity in chickens and demonstrated that the oil-emulsion inactivated avian influenza vaccine is immunogenic for geese and ducks. These results provide useful information for the application of vaccines to the control of H5N1 avian influenza in poultry, including chickens and domestic waterfowl. 相似文献
1000.
以乙肝疫苗、人喉癌细胞膜抗原为抗原,猪脾细胞为效应细胞,经体外免疫后收集应答细胞,制备PSHBV-TF PSAC-iRNA。通过抗原特异性细胞免疫功能试验证实,PSHBV-TF和PSAC-iRNA都能转移特异性细胞免疫功能。采用体外免疫法制备PSHBV-TF和PSAC-iRNA是可行的,并且具有诸多优点。 相似文献