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81.
Lei Pan Ruiqiang Weng Jinxia Zhang Jinsheng Wang Yong Tang Ning Deng 《International journal of peptide research and therapeutics》2014,20(4):565-574
Overexpression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) plays a key role in tumor angiogenesis and metastasis in tumors. VEGF/bFGF complex peptide (VBP3) was designed to elicit the body to produce both high titer anti-VEGF and anti-bFGF antibodies to inhibit tumor angiogenesis and tumor growth. BALB/c mice were immunized with the VEGF/bFGF complex peptide, and the immune responses were assayed. Splenocytes were separated from the immunized mice and the CD4, CD8 T cells and IFN-γ were assayed by Flow cytometry. The results showed that the VBP3 could effectively stimulate immune response in mice and resulted in the increase of CD4 and CD8 T cells. CD4+ T cells and CD8+ T cells were increased from 10.78 to 15.13 and 6.82 to 11.58 % respectively. Polyclonal antibodies purified from the VBP3 immunized mice showed good anti-proliferation function to lung cancer cells, and resulted in the decrease of phosphroylation level of Akt and Erk assayed by the Western-blot. Transwell assays showed that the migration of HUVEC cells was inhibited by the antibodies. The results revealed that the VBP3 have good immunogenicity and may be used as a vaccine for tumor therapy. 相似文献
82.
Co‐precipitation synthesis and luminescence properties of K2TiF6:Mn4+ red phosphors for warm white light‐emitting diodes 下载免费PDF全文
K2TiF6:Mn4+ red phosphors with different Mn4+ doping concentrations were obtained using the co‐precipitation method. X‐Ray diffraction, scanning electron microscopy, Raman spectra, Fourier transform infrared spectroscopy, photoluminescence excitation and emission spectra and decay curves were used to characterize the properties of K2TiF6:Mn4+ phosphors. Under excitation at 470 nm, an intense red emission peak around 631 nm corresponding to the 2Eg–4A2 transition of Mn4+ was observed for 2.48 mol% K2TiF6:Mn4+ phosphors and was used as the optimum doping concentration. The excellent luminescent properties of K2TiF6:Mn4+ suggest that this material might be a promising red phosphor for generating warm white light in phosphor‐converted white light‐emitting diodes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
83.
胸腺腺苷脱氨酶免疫亲和纯化和性质研究 总被引:1,自引:0,他引:1
用免疫亲和层析结合常规生化方法从人胸腺中纯化腺苷脱氨酶达电泳纯, 比活力14898U/mg, 得率34.15%.该酶分子质量为41.3ku, 约由380个氨基酸残基构成, 等电点为4.9, 最适温度37~40℃, 最适pH为7.0以腺苷或2-脱氧腺苷为底物, 其Km分别为83μmol/L和61μmol/L. 对氯汞苯甲酸能显著抑制酶活性, 二硫苏糖醇可使被抑制的活性得到部分恢复. 相似文献
84.
Background
Zinc is an essential trace element in organisms, which serves as a cofactor for hundreds of enzymes that are involved in many pivotal biological processes including growth, development, reproduction and immunity. Therefore, the homeostasis of zinc in the cell is fundamental. The zinc transporter gene family is a large gene family that encodes proteins which regulate the movement of zinc across cellular and intracellular membranes. However, studies on teleost zinc transporters are mainly limited to model species.Methodology/Principal Findings
We identified a set of 37 zinc transporters in common carp genome, including 17 from SLC30 family (ZnT), and 20 from SLC39 family (ZIP). Phylogenetic and syntenic analysis revealed that most of the zinc transporters are highly conserved, though recent gene duplication and gene losses do exist. Through examining the copy number of zinc transporter genes across several vertebrate genomes, thirteen zinc transporters in common carp are found to have undergone the gene duplications, including SLC30A1, SLC30A2, SLC30A5, SLC30A7, SLC30A9, SLC30A10, SLC39A1, SLC39A3, SLC39A4, SLC39A5, SLC39A6, SLC39A7 and SLC39A9. The expression patterns of all zinc transporters were established in various tissues, including blood, brain, gill, heart, intestine, liver, muscle, skin, spleen and kidney, and showed that most of the zinc transporters were ubiquitously expressed, indicating the critical role of zinc transporters in common carp.Conclusions
To some extent, examination of gene families with detailed phylogenetic or orthology analysis could verify the authenticity and accuracy of assembly and annotation of the recently published common carp whole genome sequences. The gene families are also considered as a unique source for evolutionary studies. Moreover, the whole set of common carp zinc transporters provides an important genomic resource for future biochemical, toxicological and physiological studies of zinc in teleost. 相似文献85.
可溶性有机碳在米槠天然林不同土层中的迁移特征 总被引:3,自引:0,他引:3
选取我国中亚热带典型的常绿阔叶林米槠天然林(Castanopsis carlesii)为研究对象,采集林内米槠凋落物并通过挖剖面法分6个土层采集土样至1m。通过浸提米槠凋落物得到可溶性有机碳(dissolved organic carbon,DOC)溶液并在室内模拟其在不同土层的淋溶过程,不仅分析了土壤性质对DOC淋溶的影响,还研究了淋溶前后DOC化学结构的变化,以阐明DOC在不同土层中的迁移特征及影响因素,探寻米槠天然林土壤的固碳潜力和DOC在土壤有机碳循环中的作用。结果表明:(1)下层土壤比上层土壤吸附DOC的能力更强,亲水性DOC与疏水性DOC间会争夺土壤颗粒表面的吸附位点,而且芳香化合物和大分子物质等疏水性DOC组分会被优先吸附;(2)红外光谱表明,芳香类和醚类等疏水性物质会优先被吸附,烷烃类物质却不易被吸附,土壤中原有的酚、醇类亲水性物质会被初始DOC中的疏水性物质置换出来;(3)土壤DOC的截留能力与粘粒、游离氧化铁含量呈极显著正相关,而与土壤有机碳和砂粒含量呈极显著负相关,其中土壤有机碳的含量是影响米槠天然林不同土层DOC截留量的关键因素。 相似文献
86.
近几十年以来,中国陆地生态系统的大气氮沉降持续增加。这种外源氮输入会影响植物多样性和生产力,进而影响植食性昆虫的种群动态。门源草原毛虫(Gynaephora menyuanensis)是青藏高原东北部高寒草地的主要植食性昆虫,种群数量爆发时会造成巨大的生态经济损失。为了探明草原毛虫种群密度如何响应氮沉降加剧,依托青海海北高寒草地“外源氮添加梯度”控制实验平台(0、25、50、100 kg N hm-2 a-1),详细调查了门源草原毛虫的种群密度及其相关的食物数量、质量和栖息地环境变化。结果表明:(1)外源氮添加显著影响门源草原毛虫的虫口密度(ANOVA:F=3.29,P=0.04),且草原毛虫虫口密度随氮添加量的增加呈线性增加趋势(R~2=0.31,P=0.005)。(2)外源氮添加梯度下,食物质量(叶片氮含量),而非食物数量(植物地上生物量和禾草地上生物量)和栖息地环境(土壤温度、湿度和光照条件),是草原毛虫虫口密度变化的关键影响因素。基于上述结果,可以预测:未来氮沉降的加剧可能促进青藏高原高寒草地门源草原毛虫的虫害爆发。研究将为全球变化背... 相似文献
87.
密蒙花黄色素是从醉鱼草科(Buddlejaceae)醉鱼草属(Buddleja Linn.)植物密蒙花树(Budd Leja officinaLis Maxim.)的花蕾中提取的一种天然食用色素。色素的主要化学成份是藏花素(Crocin)。该色素是水溶性色素,对热稳定,在pH 6—7范围内光稳定性好;氧化剂、还原剂、盐、糖、淀粉、金属离子(除Fe离子外)对色素的色译、色价无不良影响。 相似文献
88.
采用国际冻原计划(ITEX)模拟增温对植物影响的研究方法,将开项式生长室(OTC)按不同直径设置5个增温梯度,并按其直径从小到大的顺序依次标记为A、B、C、D、E 5个处理,研究了增温效应对青藏高原高寒草甸3种植物生理生化特性的影响。研究表明:(1) A~E 5个增温处理使OTC内部气温依次比对照升高了2.68 ℃、1.57 ℃、1.20 ℃、1.07 ℃ 和0.69 ℃,土壤温度依次比对照升高了1.74 ℃、1.06 ℃、0.80 ℃、0.60 ℃和0.30 ℃。(2)增温对3种植物的叶绿素含量、可溶性糖含量、可溶性蛋白含量、SOD活性、谷胱甘肽等生理生化特性产生了一系列的影响,3种植物对增温效应的响应也不尽相同。(3)增温对青藏高原3种植物生理生化特性的影响明显且复杂,适度增温0.69 ℃~1.07 ℃(D、E处理)对3种植物生理生化特性在总体上表现为正效应。 相似文献
89.
The toxic effects of furfural and acetic acid on two yeasts, Saccharomyces cerevisiae and Candida shehatae, were evaluated using an electrochemical method. Intracellular redox activities were lowered by 40% and 78% for S. cerevisiae and C. shehatae, respectively, by 8 g furfural l–1, and by 46% and 67%, respectively, by 8 g acetic acid l–1. The proposed method can accurately measure the effects of inhibitors on cell cultures.Revisions requested 27 September 2004/17 November 2004; Revisions received 15 November 2004/10 December 2004 相似文献
90.
本文通过10个地区61个样地资料分析,研究了中亚热带东部常绿阔叶林群落多样性特征及其随纬度、海拔梯度的变化。结果表明,中亚热带东部常绿阔叶林群落丰富度为49±17种(样地面积400m2),各层次的多样性表现为灌木层(包括幼树与幼苗)>乔木层>草本层。常绿阔叶林各类型间的差异远比落叶阔叶林与多样性较低的常绿阔叶林之间的差异大。各层次中变化幅度从大到小的顺序为:草本层>乔木层>灌木层。在所研究地区常绿阔叶林的群落多样性没有表现出明显的随纬度梯度和海拔梯度的变化规律。 相似文献