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1.
Dovile Stravinskiene Aiste Sliziene Lina Baranauskiene Vilma Petrikaite Aurelija Zvirbliene 《International journal of molecular sciences》2020,21(24)
Monoclonal and recombinant antibodies are widely used for the diagnostics and therapy of cancer. They are generated to interact with cell surface proteins which are usually involved in the development and progression of cancer. Carbonic anhydrase XII (CA XII) contributes to the survival of tumors under hypoxic conditions thus is considered a candidate target for antibody-based therapy. In this study, we have generated a novel collection of monoclonal antibodies (MAbs) against the recombinant extracellular domain of CA XII produced in HEK-293 cells. Eighteen out of 24 MAbs were reactive with cellular CA XII on the surface of live kidney and lung cancer cells as determined by flow cytometry. One MAb 14D6 also inhibited the enzymatic activity of recombinant CA XII as measured by the stopped-flow assay. MAb 14D6 showed the migrastatic effect on human lung carcinoma A549 and renal carcinoma A498 cell lines in a ‘wound healing’ assay. It did not reduce the growth of multicellular lung and renal cancer spheroids but reduced the cell viability by the ATP Bioluminescence assay. Epitope mapping revealed the surface-exposed amino acid sequence (35-FGPDGENS-42) close to the catalytic center of CA XII recognized by the MAb 14D6. The variable regions of the heavy and light chains of MAb 14D6 were sequenced and their complementarity-determining regions were defined. The obtained variable sequences were used to generate recombinant antibodies in two formats: single-chain fragment variable (scFv) expressed in E. coli and scFv fused to human IgG1 Fc fragment (scFv-Fc) expressed in Chinese Hamster Ovary (CHO) cells. Both recombinant antibodies maintained the same specificity for CA XII as the parental MAb 14D6. The novel antibodies may represent promising tools for CA XII-related cancer research and immunotherapy. 相似文献
2.
钨合金圆筒爆破试验破片分布的统计分析 总被引:1,自引:1,他引:0
采用圆筒爆破试验方法研究了易碎型钨合金的破片分布特征,并与93W合金的结果进行了对比.对破片的数量和质量分布特征进行了统计分析,发现易碎型钨合金的破片率明显高于93W合金,而且破片的均匀性也明显好于93W合金,但易碎钨合金的破片回收率低于93W合金,而且受装药量的影响较大. 相似文献
3.
Christos Bouras Agisilaos Konidaris 《International Journal of Communication Systems》2005,18(2):119-142
Redundant data transfers over the Web, can be mainly attributed to the repeated transfers of unchanged data. Web caches and Web proxies are some of the solutions that have been proposed, to deal with the issue of redundant data transfers. In this paper we focus on the efficient estimation and reduction of redundant data transfers over the Web. We first prove that a vast amount of redundant data is transferred in Web pages that are considered to carry fresh data. We show this by following an approach based on Web page fragmentation and manipulation. Web pages are broken down to fragments, based on specific criteria. We then deal with these fragments as independent constructors of the Web page and study their change patterns independently and in the context of the whole Web page. After the fragmentation process, we propose solutions for dealing with redundant data transfers. This paper has been based on our previous work on ‘Web Components’ but also on related work by other researchers. It utilises a proxy based, client/server architecture, and imposes changes to the algorithms executed on the Proxy server and on clients. We show that our proposed solution can considerably reduce the amount of redundant data transferred on the Web. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
4.
从理论上详细论述了钻井液振动筛叠层筛网对固相颗粒分离的影响 ,首次提出用透筛率的概念定量地描述这一影响 ,并进行了实例计算。研究表明 ,当上下层筛网随机叠加时对透筛率的影响有以下几种情况 :(1)当上下层筛网开孔尺寸相除的余数为零 ,任意组合叠层筛网的透筛率分别为某一常数 ;(2 )上层筛网目数一定时 ,下层筛网目数越大 ,则透筛率越小 ;(3)上下层筛网的目数相差越小 ,透筛率越小 ;(4 )任意目数的上下层筛网随机叠加后 ,其透筛率仅在一个小范围内变化 ,因此任一叠层筛网有其固有的透筛率属性。 相似文献
5.
侧重研究了破片式战斗部装药外形的优化设计技术。提出了装药外形与破片飞散特性(如破片飞散角,分布带宽等)之间的数学描述;建立了圆弧和对数螺线装药外形母线与战斗部其他设计参数间的数学模型。在假定约束条件下,优化设计了破片了聚焦式战斗部的结构参数;静爆试验结果表明,破片分布与理论计算吻合较好。 相似文献
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The effects of loading rate, fiber sizing, test temperature and global strain level on the adhesion strength between carbon fibers and a thermosetting epoxy (Epon 815) are studied using the single fiber fragmentation test procedure. Analytical methodology describing the viscoelastic behavior observed is also presented. The possibility of rate-temperature-interphase thickness superposition for the interfacial strength function is illustrated based on the analytical models discussed. Experimental data are discussed using Weibull statistics and also presented in the form of percent relative frequency histograms for the fiber fragments in a collective fashion. The use of histograms allows for interpretation of the skewness in the data population. 相似文献
10.
介绍研制的题示混合器结构及其混合机理。在分析球窝流场各节点速度分布的基础上,用加权平均总应变和分流混合度作为评定指标,对球窝型混合器的混合行为进行分析。通过对比实验证明球窝型混合器对于高粘流体具有良好的混合功效。 相似文献