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81.
Without any catalyst, 2,3-disubstituted-1,3-thiazolidin-4-one derivatives were synthesized efficiently via the three-component reaction of aldehyde, amine and mercaptoacetic acid in [bmim][PF6]. The whole procedure is simple and straightforward and no aqueous work-up is needed. By employing this protocol, a series of novel pyrimidine nucleoside–thiazolidin-4-one hybrids were prepared and their preliminary antiparasitic activities were also studied and reported.  相似文献   
82.
促分裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)是生物体内信号转导途径MAPK级联反应的重要组分,通过传递胞内外信号,介导生物及非生物胁迫反应、激素反应、调控细胞分化和发育过程.对水稻(Oryza sativa L.)MAPK家族的结构、作用机制、分类以及在抗逆应答、生长发育中的作用进行了综述,为水稻MAPK的深入研究和应用提供参考.  相似文献   
83.
目的:通过优化培养基和培养条件,建立太行红豆杉速生细胞系,为红豆杉细胞工厂化生产提供原种细胞系和繁殖技术。方法:以太行红豆杉为材料,筛选B5、WPS、MS等3种培养基和6-卞基嘌呤(6-BA)、萘乙酸(NAA)、2,4-二氯苯氧乙酸(2,4-D)等3种激素组合,采用液体、半固体、纸桥共3种培养方法继代培养并筛选高产细胞系。结果:B5+NAA(1.0mg/L)+6-BA(0.5mg/L)+2,4-D(1.0mg/L)为最适愈伤组织诱导培养基,诱导率达100%;B5+NAA(1.0~1.5mg/L)+2,4-D(1.5~2.0mg/L)+6-BA(0.5mg/L)为最佳继代培养基,生长量最高可达0.30g/(g·d)(鲜重)。结论:初步建立了红豆杉细胞系快速建立和繁殖新方法,用半固体培养产生初代细胞系、液体培养将细胞系同步化、纸桥培养快速繁殖细胞系,并通过检测紫杉醇含量不断更新细胞系。该细胞系体系建立方法简单,纯化速度快,易更新,产物细胞系可作为工厂化生产的原种细胞系。  相似文献   
84.
C-type lectins are a superfamily of carbohydrate-recognition proteins which play crucial roles in the innate immunity. In this study, the gene of a C-type lectin with multiple carbohydrate-recognition domains (CRDs) from scallop Chlamys farreri (designated as Cflec-3) was cloned by rapid amplification of cDNA ends (RACE) approach based on expression sequence tag (EST) analysis. The full-length cDNA of Cflec-3 was of 2256 bp. The open reading frame encoded a polypeptide of 516 amino acids, including a signal sequence and three CRDs. The deduced amino acid sequence of Cflec-3 showed high similarity to members of C-type lectin superfamily. By fluorescent quantitative real-time PCR, the Cflec-3 mRNA was mainly detected in hepatopancreas, adductor, mantle, and marginally in gill, gonad and hemocytes of healthy scallops. After scallops were challenged by Listonella anguillarum, the mRNA level of Cflec-3 in hemocytes was up-regulated and was significantly higher than that of blank at 8 h and 12 h post-challenge. The function of Cflec-3 was investigated by recombination and expression of the cDNA fragment encoding its mature peptide in Escherichia coli BL21 (DE3)-pLysS. The recombined Cflec-3 (rCflec-3) agglutinated Gram-negative bacteria Pseudomonas stutzeri. The agglutinating activity was calcium-dependent and could be inhibited by d-mannose. These results collectively suggested that Cflec-3 was involved in the immune response against microbe infection and contributed to nonself-recognition and clearance of bacterial pathogens in scallop.  相似文献   
85.
We have developed a rapid, inexpensive, and reliable assay to determine ascorbate using potassium ferricyanide as spectroscopic probe reagent. In this assay, Fe(III) was deoxidized to Fe(II) by ascorbate at pH 4.0 and then Fe(II) reacted with potassium ferricyanide to form a blue product, soluble Prussian blue (KFeIII[FeII(CN)6]). The absorbance of this product was monitored over time using a spectrophotometer at an absorption maximum of 735 nm and the amount of ascorbate can be calculated based on absorbance. A good linear relationship of the concentration of ascorbate versus absorbance was observed, and the linear regression equation was A = −0.01911 + 0.16208C (μg/ml). Moreover, the apparent molar absorption coefficient of indirect determination of ascorbate was 2.85 × 104 L/mol·cm. To demonstrate the usefulness of this assay, it was used to determine ascorbate in different samples, and we particularly investigated the uptake of ascorbate and ascorbate phosphate in osteoblasts. We found similar plateau levels of intracellular ascorbate at 24 h for ascorbate and ascorbate phosphate. The assay was robust for a variety of samples, including orange juice, fruits, and swine plasma. The assay was quick and very economical and provides results with uncertainties on the order of only 5%.  相似文献   
86.
提出一种新颖的方案使蛋白质结构信息可视化。在滑动窗口方法基础上,每一个天然氨基酸采用从氨基酸索引数据库中挑选的48种特性参数描述,在某一特定窗口下的所有氨基酸残基的参数就组成一个矩阵,通过矩阵变换得到一个方矩阵,再经过窗口的滑动就得到基于整个蛋白质的所有这些窗口矩阵的本征值矩阵。对本征值矩阵元素作图得到一系列的本征值曲线,这种曲线的轮廓不随窗口的变化而变化,这些曲线被称为蛋白质的特征曲线。为选择合适的窗口宽度、对同一类型蛋白质不同窗口宽度及不同类型蛋白质相同窗口宽度下的本征值矩阵进行了比较研究,对其潜在的用途进行了讨论。  相似文献   
87.
The interaction of benproperine phosphate (BPP) with eriochrome blue black R (EBBR) in the presence of sodium dodecylbenzene sulphonate (SDBS) was studied using resonance light scattering (RLS) technology and ultraviolet‐visual (UV‐vis) spectrophotometry. Under optimum conditions, BPP reacts with EBBP and SDBS to form a three‐component complex, which results in strong RLS signal and a new RLS peak. The enhanced RLS intensities are proportional to the concentration of BPP over the range 0.6–28.0 µg/mL, with a detection limit of 0.053 µg/mL. The affecting factors as well as the influence of coexisting substances were investigated. The results indicate that this assay method could be applied to the determination of BPP in pharmaceuticals, serum and urine samples with satisfactory results. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
88.
89.
河南省二种菊头蝠的核型研究   总被引:1,自引:0,他引:1  
取骨髓细胞采用空气干燥法对河南省二种菊头蝠的核型进行研究。结果:1.中菊头蝠染色体数为2n=62,N,F=60,属于Harada等划分的菊头蝠属的第1类群,即最原始的类群;2.马铁菊头蝠染色体数为2n=58.N.F=60,属于Harada等划分的菊头蝠属的第2类群;3.马铁菊头蝠的核型为国内首次报道。  相似文献   
90.
秦丹  徐存拴 《遗传》2013,35(11):1253-1264
非编码DNA序列是指基因组中不编码蛋白质的DNA序列。这些序列可以结合调节因子、转录为功能性RNA、单独或协同地调节生理活动和病理过程。文章围绕基因表达调控作用, 总结了近几年非编码DNA序列的研究成果, 对其结构、功能和可能的作用机制进行了初步阐述, 介绍了目前鉴定非编码DNA序列中功能元件的计算方法和实验技术, 并对非编码DNA未来的研究进行了展望。  相似文献   
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