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991.
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
992.
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
993.
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
994.
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
995.
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
996.
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
997.
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
998.
A. N. Valuiskikh Yu. A. Romashkova A. V. Danilkovich K. G. Freze G. T. Sukhikh E. V. Makarov 《Bulletin of experimental biology and medicine》1997,123(3):276-278
Similar to chorionic gonadotropin, synthetic fragment of the β-subunit of chorionic gonadotropin (128th–145th amino acid),
inhibits mitogen-stimulated proliferation of human lymphocytesin vitro and binds to membrane receptors of human peripheral blood monocytes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 319–322, March, 1997 相似文献
999.
Sheikh-Zade YR Galenko-Yaroshevskii PA Cherednik IL 《Bulletin of experimental biology and medicine》2002,134(1):1-4
We propose a new mechanism of atrial fibrillation basing on the results of 30 series of acute experiments on anesthetized cats. In brief, combination of two or more arrhythmogenic factors shortens the interval between the inward and outward ionic currents in cardiomyocytes to a critical value. Under these conditions repolarization of cardiomyocyte membrane reaches the excitation threshold before complete inactivation of the depolarizing currents. This inevitably results in autoexcitation of myocytes (or extrasystole), that in turn promotes repolarization. Once occurred, autoexcitation turns into self-triggering activity resembling tachyarrhythmia paroxysm. 相似文献
1000.
Yu Liu Xianghong Wang Angela K F Lo Yong Chuan Wong Annie L M Cheung Sai Wah Tsao 《Journal of medical virology》2002,66(1):63-69
Nasopharyngeal carcinoma is closely associated with Epstein-Barr virus (EBV) and the EBV encoded latent membrane protein-1 expression (LMP1) is commonly found in the tumour cells. LMP1 has been shown to be involved in modulation of cell growth in B cells but the biological properties of LMP1 expression in nasopharyngeal carcinoma cells are less defined. In this study, a full length LMP1 gene was introduced into an EBV negative nasopharyngeal carcinoma cell line, CNE2, and five LMP1-expressing clones were isolated. Expression of LMP1 did not confer cell growth advantage in CNE2 cells; instead, it induced growth inhibition both in vitro and in vivo. In addition, the LMP1 transfected cells were more susceptible to cisplatin-induced cell death and showed 1.4-4.0-fold increased sensitivity to cisplatin compared to the vector infected control clones. The effect of LMP1 on the balance of Bcl-2 and Bax ratio may play a role in inducing susceptibility to cisplatin-induced cell death. These results demonstrated that LMP1 did not confer growth advantage in CNE2 cells, suggesting that expression of LMP1 may not be crucial in sustaining cell growth in established cell lines. Alternatively, LMP1 alone may not be sufficient to facilitate nasopharyngeal carcinoma cell growth and additional oncogenic factors may be needed along with LMP1 in modulating the malignant property of nasopharyngeal carcinoma. 相似文献