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51.
Molecular cloning and expression analysis of pig CD81 总被引:1,自引:0,他引:1
Cho KW Kim SJ Park CG Park J Cho JY Kang HS Chun T 《Veterinary immunology and immunopathology》2007,120(3-4):254-259
CD81, also known as TAPA-1 (target of antiproliferative antibody 1), is a member of the tetraspanin family of proteins and a component of the B cell co-receptor complex. Several studies have shown that CD81 plays significant roles in a variety of immune responses, including activation of B cells and T cells. In this study, we cloned pig Cd81 cDNA using RT-PCR coupled with rapid amplification of cDNA ends (RACE)-PCR and determined the complete cDNA sequence of pig Cd81. Pig Cd81 cDNA contains an open reading frame (711 bp) encoding 236 amino acids. The identity of pig CD81 with those of human, cattle, rat, and mouse are 90.30%, 92.26%, 86.22%, and 86.22%, respectively. Alignment of the CD81 amino acid sequence with those of mammalian species showed that the large extracellular loop (LEL) is the most divergent, whereas other domains are largely conserved. Pig Cd81 mRNA was detected by RT-PCR in a broad range of tissues, including lymphoid tissues as well as nonlymphoid tissues, indicated variety of cellular functions of CD81 in most pig tissues. Flow cytometry analyses demonstrated that human CD81 antibody recognizes a pig CD81 on the cell surface. Further, immunohistochemistry analysis using human CD81 antibody on pig spleen was revealed that CD81 expression is widely diffused in spleen tissue. Future study will be focused on defining the functional role of CD81 during the course of pig infectious diseases. 相似文献
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依据复杂自适应系统理论,采用自下而上研究思路,将供应链主体行为与宏观系统特征涌现结合起来.将供应链分为创新型与模仿型,进行主体行为建模;运用遗传算法模拟主体演化进程,并在SWARM平台进行仿真,仿真结果凸显创新在供应链演化中的重要作用,证实个体简单自主行为能够导致系统复杂宏观特征涌现的复杂自适应系统基本原理. 相似文献
54.
《Land Degradation u0026amp; Development》2017,28(7):2315-2320
China's soil pollution is serious, with 16·1% of all soil samples exceeding soil quality standard according to a national soil quality survey. On 31 May 2016, the Chinese government unleashed an ambitious plan to address its soil pollution problem. The large scale and fast pace of the proposed plan pose many challenges. There are biogeochemical complexities governing the fate and transport of soil contaminants that require more thorough study. There are also human‐related complexities and dynamic feedback loops, which determine the behaviour of farmers, industrial polluters, remediation practitioners and regulators. Soil pollution prevention and remediation also have externalities and spillover effects ranging from greenhouse gas emission to social justice. Rigorous policy instruments must be developed to account for complex human behaviour, to strengthen risk management and to encourage interdisciplinary scientific research. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
55.
氮素形态对小麦幼苗叶绿体色素蛋白复合体含量及希尔反应活性的影响 总被引:1,自引:0,他引:1
采用水培方法研究了不同氮素形态对小麦幼苗叶绿体色素、色素蛋白复合体及希尔反应活性的影响.结果表明,50%硝态氮 50%铵态氮处理时,电泳条带中31~43kD范围内的多肽组分及高分量区属于PSⅠ的多肽组分含量最高,两种氮素形态单独施用时最低;叶片的光吸收能力、叶绿素含量及叶绿体蛋白含量均在氮素形态配比相等时达到最大,两种氮素形态单独施用时最低;希尔反应活性则随着铵态氮比例降低而降低. 相似文献
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M. Kvas E. T. Steenkamp A. O. Al Adawi M. L. Deadman A. A. Al Jahwari W. F. O. Marasas B. D. Wingfield R. C. Ploetz M. J. Wingfield 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):195-199
Mango malformation, caused by Fusarium mangiferae, represents the most important floral disease of mango. The first symptoms of this disease were noticed in the beginning of
2005 in plantations at Sohar in the Sultanate of Oman. The affected inflorescences were abnormally enlarged and branched with
heavy and dried-out panicles. Based on morphology and DNA-sequence data for the genes encoding translation elongation factor
1α and β-tubulin, the pathogen associated with these symptoms was identified as F. mangiferae. 相似文献
59.
The conservation of historic buildings and their environment is an unavoidable problem in urban construction. In this paper, the authors give a few new thoughts about the problem. First, the historic buildings are important part of the core power in city competition.Second,the conservation work should be combined with their development. Third, a classified and multilevel system of protection and reuse of old buildings should be set up. 相似文献
60.
东北梅花鹿与东北马鹿种间杂交F#-1能育性的细胞遗传学基础的研究 总被引:1,自引:0,他引:1
本文对东北梅花鹿与东北马鹿的F#-1代杂种鹿的能育性进行了研究。从F#-1的染色体组型、G带、C带和Ag—NORs的观察表明,F#-1双亲鹿的染色体高度同源,差异只涉及一个罗伯逊易位;精母细胞联会复合体显示出F#-1减数分裂时,同源染色体能很好的配对,形成31个完整的常染色体联会复合体,1个端着丝粒染色体/中着丝粒染色体的三价体和XY双价体。三价体的顺式构型有利于同源染色体能平均分配到子细胞中而产生平衡配子;睾丸组织切片证实了F#-1的生殖腺生长发育正常。所以,F#-1两性皆育。说明其亲本鹿之间隔离机制不完善。这两种鹿应属同一个孟德尔群体。 相似文献