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131.
Dongchao Xu Ajuan Liu Xuan Wang Ming Zhang Zunyi Zhang Zhou Tan Mengsheng Qiu 《Developmental neurobiology》2018,78(1):39-50
Accurate quantification of gene expression is fundamental for understanding the molecular, genetic and functional bases of tissue development and diseases. Quantitative real‐time PCR (qPCR) is now the most widely used method of quantifying gene expression due to its simplicity, specificity, sensitivity, and wide quantification range. The use of appropriate reference genes to ensure accurate normalization is crucial for the correct quantification of gene expression from the early development, maturation, aging to injury processes in the central nervous system (CNS). In this study, we have determined the expression profiles of 12 candidate housekeeping genes (ACTB, CYC1, HMBS, GAPDH, HPRT1, RPL13A, YWHAZ, PPIA, RPLP0, TFRC, GUS, and 18S rRNA) in developing mouse brain and spinal cord. Throughout development, there was a significant degree of fluctuations in their expression levels, indicating the importance and complexity of finding appropriate reference genes. Three software including BestKeeper, geNorm and NormFinder were used to evaluate the stability of potential reference genes. GUS was the most stable gene and GUS/YWHAZ were the most stable reference gene pair across different developmental stages in different CNS regions, whereas HPRT1 and GAPDH were the most variable genes and thus inappropriate to use as reference genes. Therefore, our results identified GUS and YWHAZ as the best combination of two reference genes for expression data normalization in CNS developmental studies. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 39–50, 2018 相似文献
132.
高度恶性肿瘤如肝癌或恶性黑色素瘤病人即使手术治疗,仍然有相当多的病人预后不好,或发生转移。本文研究了自行合成的4-氨基苯酚维甲酰胺(4-HPR),一种维甲酸的衍生物,通过观察对肝癌细胞和恶性黑色素瘤细胞的作用,发现该衍生物具有较强的抑制肝癌细胞迁移能力,7721-k3肝癌细胞的迁移细胞数从对照组的201(27.2,经过6h的作用后即下降到58±5.03(p<0.05,n=4);黑色素瘤细胞则从302±30.1下降到254±25.04(p<0.05,n=4);侵润能力也显著下降,7721-k3细胞穿过人工模拟基底膜的细胞数从对照组的27±13.1下降到11.2±3.3,黑色素瘤细胞则从67.5±10.1下降到24.3±3.2(p<0.05,n=3)。而且发现3μmol/L 4-HPR作用B16黑色素瘤细胞48h可诱导37.11±0.94%细胞的调亡,与相同微克分子浓度的维甲酸相比,具有显著性差别(p<0.05)。但是不能显著诱导7721-k3细胞凋亡。4-HPR诱导B16黑色素瘤细胞凋亡的作用机制尚不清楚,我们利用与肿瘤恶性程度密切有关的乳糖基神经酰胺磺酰基转移酶(CST)基因,转染B16细胞使之高表达以后,可以部分抑制这些细胞对4-HPR诱导凋亡的敏感性,但是不能完全抑制。4-HPR是目前已知毒副作用最小的维生素A类化合物,有可能成为恶性黑色素瘤或肝癌治疗的一个有效的药物。 相似文献
133.
Physiological integration has been documented in many clonal plants growing under resource heterogeneity. Little is still known about the response of physiological integration to heterogeneous ultraviolet-B radiation. In this paper, the changes in intensity of physiological integration and of physiological parameters under homogeneous and heterogeneous ultraviolet-B radiation (280-315 nm) were measured in order to test the hypothesis that in addition to resource integration a defensive integration in Trifolium repens might exist as well. For this purpose, homogeneous and heterogeneous ultraviolet-B radiation was applied to pairs of connected and severed ramets of the stoloniferous herb Trifolium repens. Changes in intensity of water and nutrient integration were followed with acid fuchsin dye and 15N-isotope labeling of the xylem water transport. In order to assess the patterns of physiological integration contents of chlorophyll, ultraviolet-B absorbing compounds, soluble sugar and protein were determined and activities of superoxide dismutase (SOD) and peroxidase (POD) measured. When ramets were connected and exposed to heterogeneous UV-B radiation, the velocity of water transportation from the UV-B treated ramet to its connected sister ramet was markedly lower and the percentage of 15N left in labelled ramets that suffered from enhanced UV-B radiation was higher and their transfer to unlabelled ramets lower. In comparison with clones under homogeneous ultraviolet-B radiation, the content of chlorophyll, ultraviolet-B absorbing compounds, soluble sugar and activities of SOD and POD increased notably if ultraviolet-B stressed ramets were connected to untreated ramets. Chlorophyll and UV-B absorbing compounds were shared between connected ramets under heterogeneous UV-B radiation. This indicated that physiological connection improved the performance of whole clonal plants under heterogeneous ultraviolet-B radiation. The intensity of physiological integration of T. repens for resources decreased under heterogeneous ultraviolet-B radiation in favor of the stressed ramets. Ultraviolet-B stressed ramets benefited from unstressed ramets by physiological integration, supporting the hypothesis that clonal plants are able to optimize the efficiency of their resistance maintaining their presence also in less favorable sites. The results could be helpful for further understanding of the function of heterogeneous UV-B radiation on growth regulation and microevolution in clonal plants. 相似文献
134.
135.
中国蚌螨属支序分类分析(蜱螨亚纲:蚌螨科) 总被引:1,自引:0,他引:1
选择35个特征对我国蚌螨属15种的支序分析结果表明:蚌螨P-Ⅳ(胫节)端腹部的指状突是将它们聚集成两群的主要特征.今村蚌螨P-Ⅳ端腹部仅具有短矩,与外群最近,认为是我国的蚌螨属水螨中最原始的种类;雌螨前殖吸盘板的形态影响戊蚌螨亚属与多盘蚌螨亚属的种类聚类,由此推测可以将蚌螨P-Ⅳ端腹部的指状突与雌螨前殖吸盘板的形态也作为蚌螨亚属的区分特征.由于殖吸盘结构简单是祖征态之一,因此认为具有5对殖吸盘的邻近蚌螨比6对殖吸盘的厚蚌螨更原始.雌螨具有1对殖吸盘板的寄蚌螨亚属种类与沃蚌螨亚属种类在支序系统树中形成姊妹群,结果支持Vidrine 将沃蚌螨亚属从寄蚌螨亚属中分离的修订. 相似文献
136.
James Love Filippo Mancia Lawrence Shapiro Marco Punta Burkhard Rost Mark Girvin Da-Neng Wang Ming Zhou John F. Hunt Thomas Szyperski Eric Gouaux Roderick MacKinnon Ann McDermott Barry Honig Masayori Inouye Gaetano Montelione Wayne A. Hendrickson 《Journal of structural and functional genomics》2010,11(3):191-199
The New York Consortium on Membrane Protein Structure (NYCOMPS) was formed to accelerate the acquisition of structural information on membrane proteins by applying a structural genomics approach. NYCOMPS comprises a bioinformatics group, a centralized facility operating a high-throughput cloning and screening pipeline, a set of associated wet labs that perform high-level protein production and structure determination by x-ray crystallography and NMR, and a set of investigators focused on methods development. In the first three years of operation, the NYCOMPS pipeline has so far produced and screened 7,250 expression constructs for 8,045 target proteins. Approximately 600 of these verified targets were scaled up to levels required for structural studies, so far yielding 24 membrane protein crystals. Here we describe the overall structure of NYCOMPS and provide details on the high-throughput pipeline. 相似文献
137.
138.
139.
稀酸水解玉米芯制备丁二酸 总被引:3,自引:1,他引:3
利用正交设计得到稀H2SO4水解玉米芯制备混合糖液的优化工艺:玉米芯料液比1∶5(质量体积比),物料粒径250~380μm、H2SO4用量3%(体积分数)、水解温度126℃、反应时间2.5 h。此工艺条件下的总糖收率达90%,总糖质量浓度为60 g/L,发酵抑制物糠醛含量为0.87 g/L,5-羟甲基糠醛含量为0.68 g/L。在此基础上利用活性炭吸附和Ca(OH)2中和对玉米芯混合糖液进行脱毒及脱盐处理,SO42-脱除率达96%,色素脱除率为96%,糠醛、5-羟甲基糠醛及多酚类物质脱除率均高于50%。处理后的玉米芯多组分糖液作为产琥珀酸放线杆菌(Actinobacillus succino-genes)NJ113的发酵C源,当培养基中初始总糖质量浓度为50 g/L时,丁二酸收率为61.68%,丁二酸质量浓度为30.8 g/L;初始总糖质量浓度为70 g/L时,丁二酸收率仍可达50%以上,丁二酸质量浓度为35.2 g/L。发酵实验表明,将经过脱毒脱盐处理的玉米芯多组分糖液替代葡萄糖作为C源发酵制备丁二酸具有可行性。 相似文献
140.
吕沁风吴忠华郑伟徐琦孟军李禾 《现代生物医学进展》2011,11(3):493-496
目的:研究不同的加热方式对嗜肺军团菌环介导等温扩增检测法的影响方法:用已知的13株嗜肺军团菌样本,采用空气浴、水浴和PCR仪同时进行环介导等温扩增,观察沉淀反应、荧光反应以及产物电泳结果。结果:水浴和PCR仪加热LAMP反应的沉淀产物较多,荧光反应较强,电泳检测结果较为明显。空气浴的3种检测结果均较弱。结论:采用水浴和PCR仪进行环介导等温扩增反应的效果较好,从仪器设备的成本及实验条件考虑,采用水浴是环介导等温扩增反应首选的加热方式。 相似文献