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1.
In the previous study, we cloned a new gene, named NGX6, related to nasopharyngeal carcinoma (NPC) at 9p. To study its function in the pathogenesis of NPC, we have investigated changes in protein synthesis between NPC cell line HNE1 and that transfected with the gene. Using high-resolution two-dimensional electrophoresis, we found that 22 protein spots showed variations that were significant and reproducible. Analysis of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and database searches identified seven proteins that were upregulated and seven proteins that were downregulated. These proteins included Fas, zinc-finger protein (ZNF), RAB, and Ah receptor-interacting protein (AIP). The functional implications of the identified proteins are discussed.  相似文献
2.
Luo C  Li B 《Heredity》2003,90(5):405-409
A diploid-dependent regulatory mechanism of gene expression for spatial patterning of the eye in vertebrates has been determined by analyzing the phenotypes of haploid goldfish embryos. There are two gene loci in charge of eye spatial patterning during embryonic morphogenesis. The expressional probability for each copy of the two genes in a set of chromosomes is 50%. A pair of genes in two sets of homologous or heterologous chromosomes is 100% and essential for normal gene expression. The haploid condition itself would result in the obstruction of gene expression and abnormal development because the diploid-dependent regulatory apparatus will regulate gene expression in a haploid embryo according to the same rule as in the diploid embryo.  相似文献
3.
NGX6是克隆的鼻咽癌相关基因,它的功能与作用机制目前尚不十分清楚.通过脂质体转染把NGX6导入鼻咽癌细胞株中,采用双向凝胶电泳分离细胞内所有蛋白质,通过软件分析,找到与未处理细胞表达差异的蛋白质,通过质谱分析和生物信息学资料处理.鉴定出七种表达上调的蛋白质,其中包括Fas蛋白,锌指蛋白(ZNF),主要组织相容性抗原Ⅱ(MHCⅡ)等.Fas蛋白参与细胞凋亡的信号传导途径,它的上调可以促进细胞凋亡;ZNF蛋白参与基因的转录调控,它的上调也可影响细胞异常增殖的信号传导通路;MHCⅡ可以促进机体对肿瘤细胞的免疫应答.这些结果说明NGX6可能通过多种途径抑制鼻咽癌细胞的生长,为研究NGX6的作用机制提供了很好的实验资料,对鼻咽癌的基因治疗奠定了一定的研究基础,也为研究其他基因的作用机制提供了新思路.  相似文献
4.
蓖麻品种遗传多样性与亲缘关系的SRAP分析   总被引:4,自引:0,他引:4       下载免费PDF全文
利用SRAP技术对81份蓖麻品种材料亲缘关系进行了分析,实验选用20对SRAP引物组合,在81份蓖麻材料中共扩增出263条带,多态性条带计214条,多态性条带比率(PPB)为81.37%,遗传相似系数变幅范围在0.32558~0.92973,显示了蓖麻品种的遗传多样性较丰富。从分子聚类结果分析表明,在相异系数0.43为阈值时,可将81份蓖麻材料分为4个类群L1-1、L1-2、L1-3和L1-4;若在相异系数0.287为阈值时,又可将L1-4大类群分为两个亚类群L2-1和L2-2。从聚类图得知,聚在同一亚类群的蓖麻品种大多数所处的地域相近或者是由同一育种单位所选育,其类内的品种基因型遗传相似系数较高,类间的品种遗传差异相对较大,该分子聚类树状图可为蓖麻栽培种种质资源遗传多样性与亲缘关系在育种的利用上提供科学依据。  相似文献
5.
亚麻组织培养高频不定芽诱导体系   总被引:4,自引:0,他引:4  
对适合南方地区冬季种植的纤用亚麻品种组织培养过程中基本培养基、激素配比、外植体材料的基因型和苗龄以及再生不定芽的生根条件进行了比较研究。结果表明,适合于亚麻白花品种组织培养的最佳培养基为YB1,不定芽诱导率可达98.50%。在此培养基上,白花、黑亚4号、K6531、K7697、HI026、HI045、I039和阿丽亚那下胚轴不定芽的诱导率分别为98.50%、98.50%、56.50%、42.47%、54.40%、0、27.13%和97.30%,平均出芽数为11.43、9.33、2.17、0.77、1.10、0、0.90和10.68。苗龄为7-10天的下胚轴最适于诱导不定芽,随苗龄增加,不定芽的诱导率呈下降趋势。RB5培养基最适于不定芽的生根,生根率达100%,平均生根数为15.3。实验还确定了亚麻对卡那霉素、氨苄青霉素和头孢霉素的抗性浓度阈值。  相似文献
6.
亚麻生物技术研究进展   总被引:3,自引:0,他引:3  
简要综述了近几年有关亚麻应用和基础研究的进展,重点介绍了亚麻组织细胞的再生、体细胞发生、原生质体分离培养、细胞悬浮培养、花药培养,以及亚麻转基因技术的研究成果,讨论了目前在亚麻研究中出现的问题。  相似文献
7.
The three-dimensional structure of native SHL-I, a lectin from the venom of the Chinese bird spider Selenocosmia huwena, has been determined from two-dimensional 1H NMR spectroscopy recorded at 500 and 600 MHz. The best 10 structures have NOE violation <0.3 Å, dihedral violation <2 deg, and average root-mean-square differences of 0.85 + 0.06 Å over backbone atoms. The structure consists of a three-stranded antiparallel -sheet and three turns. The three disulfide bridges and three-stranded antiparallel -sheet form a inhibitor cystine knot motif which is adopted by several other small proteins, such as huwentoxin-I, -conotoxin, and gurmarin. The C-terminal fragment from Leu28 to Trp32 adopts two sets of conformations corresponding to the cis and trans conformations of Pro31. The structure of SHL-I also has high similarity with that of the N-terminus of hevein, a lectin from rubber-tree latex.  相似文献
8.
人类新基因netrin-G 2的初步分析   总被引:3,自引:0,他引:3       下载免费PDF全文
Netrins是与层粘连蛋白相关的、高度保守的小分子分泌蛋白家族成员,在细胞迁移和轴突导向活动中具有重要的作用,其同源物在多种模式动物中均已发现.Netrins分为2个亚家族:netrins和netrin-Gs;其中的netrin-G亚家族各成员之间具有高度的相似性.目前,在人类中得到确证的只有netrin-G1,推测在人类中应该还有其它的netrin-G亚家族成员以及编码它的基因.从20周龄人胚中提取脑组织的总RNA,用PCR cDNA文库试剂盒制备脑组织cDNA文库,再用特异性引物进行PCR扩增,得到1条人netrin-G的全长cDNA,命名为人netrin-G2,用Northern杂交研究其表达,用进化树分析其与netrin家族各成员间的关系;证实人netrin-G2确实为netrin-G亚家族的1个新成员,该基因位于染色体的9q34,大小为2 428 bp,含有1个1 593 bp的假定开放阅读框,起始密码子为86位的甲硫氨酸,终止密码子为1 678位的TGA,可编码1个大小为530个氨基酸的蛋白质;Northern杂交显示,人netrin-G2在脑组织中特异性表达,而在其它组织中却很少发现,推测人netrin-G2可能在中枢神经系统的发育过程中具有重要的作用,可能与刺激性神经冲动的传递以及神经调节有关.  相似文献
9.
大鼠肺泡巨噬细胞对人胚肺成纤维细胞增殖的抑制作用   总被引:2,自引:0,他引:2  
Zhang JS  Yu FJ  Qu SL  Li X 《生理学报》2002,54(3):225-228
实验采用[^3H]TdR掺入标记法测定微量培养人胚肺成纤维细胞的增殖,观察到健康大鼠的肺泡巨噬细胞(alveolar macrophage,AM)可抑制成纤维细胞增殖。经调理的酵母多糖激活后,AM的抑制作用加强;而经消炎痛处理的AM,抑制作用转为被促进增殖作用所取代;测定AM上清液中前歹腺素E(prostaglandin E,PGE)含量,显示其抑制作用与PGE含量相关。结果提示,AM有抑制作促进肺成纤维细胞增殖的双重作用,正常时以抑制作用占优势;PGE可能是AM产生的主要的肺纤维化抑制因子。  相似文献
10.
Tian W  Zeng XM  Li LX  Jin HK  Luo QZ  Wang F  Guo SS  Cao Y 《Immunogenetics》2006,58(2-3):113-121
Previous studies have identified several HLA-B specificities that are associated with nasopharyngeal carcinoma (NPC) in populations of Chinese descent, in particular HLA-B35, -B38, -B46, and -B58. Perhaps except for HLA-B46, other associations cannot be simply accounted for by the linkage disequilibrium between HLA-A and B loci. The human major histocompatibility complex (MHC) class I chain-related gene A (MICA) maps 46 kb centromeric to HLA-B and is highly polymorphic; it encodes a stress-inducible protein which functions as a ligand for the NKG2D/DAP10 complex to activate natural killer (NK) cells, γδ T cells, and CD8+ T cells. We postulated MICA gene as a susceptibility factor for nasopharyngeal carcinoma, an Epstein–Barr virus-associated malignancy. In this study, 218 unrelated patients newly diagnosed with NPC and 196 randomly selected healthy controls from southern China mainland were analyzed for the short tandem repeat polymorphism of exon 5 of MICA gene (MICA-STR) and MICA gene deletion, using fluorescent polymerase chain reaction-gene scanning (PCR/size-sequencing) and polymerase chain reaction-sequence-specific priming (PCR/SSP) technology. MICA*A9 was present at significantly increased frequency in the patient group (P C=0.0001002, OR=2.528, 95% CI=1.636–3.907), whereas the frequency of MICA*A5.1 was significantly decreased (P C=0.006, OR=0.594, 95% CI=0.437–0.806). Gender-based stratification revealed a significant increase of MICA*A9 frequency (P C=0.000072, OR=3.255, 95% CI=1.855–5.709) and a significant decrease of MICA*A5.1 frequency (P C=0.000737, OR=0.486, 95% CI=0.337–0.702) in male patients with NPC (N=166), compared with male normal controls (N=120). A significant interaction between MICA*A9 and gender was observed (=41.58, P=0.0001). Statistics also revealed heterogeneity of effects among MICA*A5.1/MICA*A9-bearing phenotypes and a dose-dependent effect of MICA*A5.1 and MICA*A9 on NPC risk in male subgroup. This constitutes the first demonstration of a gender-specific association between MICA-STR polymorphism and NPC, which could largely be attributable to the underlying gender-related mechanisms that modulate MICA gene expression. The results provide strong supporting evidence suggesting that MICA*A9 may be a genetic risk factor for NPC in male individuals in this population. The potential interaction between MICA and other non-HLA host factors and environmental exposures remains to be further studied.  相似文献
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