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31.
Chen SJ Foster WR Jure-Kunkel MN Girit E Abraham R Hefta LJ Gao S Yonan CR Lin JH Dambach DM 《Veterinary immunology and immunopathology》2008,126(3-4):377-381
CD137 plays an important role as a co-stimulatory molecule in activated T cells. Agonistic CD137 specific antibodies have been investigated as therapeutic agents to promote tumor-specific immune responses by direct activation of T cells. As part of the pre-clinical pharmacological evaluation of cynomolgus monkeys, monkey CD137 was cloned and characterized. The deduced amino acid sequence encoded a full-length gene of 254 amino acids 95% identical to human CD137. Sequence variants identified in monkey CD137 include four splice variants lacking the transmembrane domain. These variants were detectable in human including two previously unreported variants. Two missense single nucleotide polymorphisms were detected present in 42 and 50% of 36 monkeys tested. In both monkey and human, mRNA expression of full-length CD137 and splice variants were significantly increased in peripheral blood mononuclear cells (PBMCs) upon stimulation by anti-CD3 antibodies. Recombinant monkey CD137 protein was bound with high affinity by an agonistic anti-human CD137 antibody but not by an anti-mouse CD137 antibody. In summary, compared to human, monkey CD137 showed distinct extracellular domain amino acid sequence and sequence polymorphisms. Thus, antibodies directed against epitopes in this extracellular domain could have differences in pharmacologic activity between cynomolgus monkeys and human or across individual cynomolgus monkeys. 相似文献
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五节芒的分化类型及生产性状的比较研究 总被引:2,自引:0,他引:2
通过长期的引种栽培,发现五节芒分化出宽叶和窄叶类型。经对形态特征、生产性状的比较研究,证明两个类型差异显著,性状稳定。还证明,宽叶类型的生产性状明显优于窄叶类型。 相似文献
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Estepa JC Garfia B Gao PR Cantor T Rodriguez M Aguilera-Tejero E 《Equine veterinary journal》2003,35(3):291-295
REASONS FOR PERFORMING STUDY: Parathyroid hormone (PTH) plays a critical role in the regulation of mineral metabolism in mammals. Until recently, the standard method for PTH measurement has been the 2nd generation intact-PTH (I-PTH) assay. Current evidence indicates that the I-PTH assay binds to the PTH molecule and to an inactive N-terminally truncated PTH fragment that tends to accumulate in the blood of uraemic patients. Therefore, a new 3rd generation PTH assay that detects only the whole PTH molecule (W-PTH; cyclase-activating PTH [CAP]) has been developed. OBJECTIVES: To validate this more specific W-PTH assay for measurement of equine PTH and evaluate its clinical utility. METHODS: W-PTH and I-PTH were measured in plasma samples from normal horses (adults and foals) and horses with nutritional secondary hyperparathyroidism (N2HPT) and with chronic renal failure (CRF). Replicate measurements and dilutional paralellism were used for assay validation. Changes in blood ionized calcium were induced by EDTA and CaCl2 administration. RESULTS: Performance of the W-PTH assay (accuracy, sensitivity, specificity and ability to detect changes in PTH in response to changes in calcium) was similar to that of the I-PTH assay. Surprisingly, the relative W-PTH concentration in normal horses and foals was higher than the relative I-PTH concentration. W-PTH values remained higher than I-PTH during acute hypo- and hypercalcaemia. An increase in both W-PTH and I-PTH concentrations was found in horses with N2HPT. In horses with CRF, W-PTH and I-PTH values were very low and no increase in I-PTH was observed. CONCLUSIONS: The W-PTH assay can be used for measurement of equine PTH. POTENTIAL RELEVANCE: The use of W-PTH assay is likely to improve the diagnosis of mineral metabolism in horses. 相似文献
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@@进入新世纪以来,伴随SARS、禽流感和猪链球菌病等疫情在全球范围内的传播,对世界各国人民的身体健康构成极大威胁。因此,国家逐步加大对动物疫病的防控,相继颁布了《中华人民共和国动物防疫法》《动物检疫管理办法》等法律法规,使我国动物防疫和检疫工作走上了有法可依、有章可循的规范化、法制化轨道。屠宰检疫是动物检疫工作的重要组成部分,是保证人民群众食肉安全的重要手段。猪肉及猪产品是广大群众餐桌上不可或缺的食品,国家为保证生猪产品质量安全,保障人民身体健康对生猪屠宰实行定点屠宰、集中检疫,从而使重大疫病的发生和流行得到有效控制。 相似文献
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本试验用SDS-PAGE技术对分离自青海、湖北、广西省流产猪的鹦鹉衣原体抗原结构进行分析,发现这些菌株的抗原结构图谱相似,即共同含有主外膜蛋白MOMP和其他一些主多肽。并以D13株免疫兔子制备的抗血清作为探针,用免疫印迹试验检查其与各株鹦鹉衣原体抗原分子的反应关系。证实D13株的主要抗原38KD(MOMP)、60KD、80KD和110KD具有抗原性,它们可刺激机体产生抗体免疫应答。该抗血清不仅可与 相似文献
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牛腿山羊为个体大,肉用性能好的山地品种,研究牛腿山羊对炎热气候的适应性,目的在于为同类地区引起该品种提供依据,本试验于1995年7月28日至8月1日在新乡县朝阳种羊场进行,随机选取健康,空怀,经产的成年牛腿山羊和本地槐山羊各12只,采集血样,实验室内测定T4和K^+含量,选其中各6只,连续3日测定6:00-7:00时和15:00-16:00时的毛丛温度,直肠温度,呼吸率和心率,并且同时测定羊舍内白 相似文献