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1.
植物金属硫蛋白及其重金属解毒机制研究进展   总被引:22,自引:0,他引:22  
全先庆  张洪涛  单雷  毕玉平 《遗传》2006,28(3):375-382
金属硫蛋白是一类分子量较小、富含Cys的金属结合蛋白,广泛分布于生物界.近年来从植物中克隆到许多编码金属硫蛋白的基因,并在研究基因表达模式、组织表达特异性以及基因结构,如启动子、内含子在染色体上的定位等方面取得了一定进展,但对其功能的研究还处于起步阶段.很多实验表明,植物金属硫蛋白可以通过其大量的Cys残基螯合重金属并清除活性氧,使植物免受氧化损伤.文章介绍了植物金属硫蛋白的分类、特征、基因结构及其在植物重金属解毒中的作用.  相似文献
2.
玉米杂种与亲本穗分化期功能叶基因差异表达与杂种优势   总被引:18,自引:0,他引:18  
田曾元  戴景瑞 《遗传学报》2003,30(2):154-162
为探讨玉米杂种优势的分子机理,以10个玉米自交系及其组配的38个杂交种为材料,利用cDNA-AFLP技术,分析杂种与亲本在玉米雌穗小穗分化期功能叶片的基因差异表达类型与主要农艺性状的杂种表现及杂种优势的关系。研究表明:(1)杂种的基因相对于其双亲,存在质和量的表达差异,其中质的差异表达类型包括:单亲沉默表达,双亲沉默表达,亲本显性表达和杂种特异表达等类型。(2)在雌穗小穗分化期,同一差异表达类型中不同杂交组合间差异很大;从总体平均看,杂种特异表达类型占25.22%,亲本显性表达类型占21.46%,双亲沉默表达类型占8.27%,单亲沉默表达类型占33.49%。(3)单亲沉默表达与株高的杂种表现呈显著正相关;双亲沉默表达与穗粗的杂种优势呈显著负相关,显性表达与行粒数和单株粒重的杂种优势呈显著负相关,其余表达类型与所有农艺性状杂种表现及杂种优势均不相关,并对结果进行了讨论。  相似文献
3.
Spermatogenesis is a complex process. Duringspermatogenesis, the production of sperm occurs withinthe testicular seminiferous tubules through three separatedphases. First of all, diploid germ cells, primitivespermatogonia, will self renew to amplify and producetypes A and B spermatogonia. Type B spermatogonia willdifferentiate into primary spermatocytes. Then, meioticdivisions of spermatocytes will produce round spermatids.Finally, after a series of biochemical and morphologicalchanges, sper…  相似文献
4.
Compared to rice, wheat exhibits characteristic growth habits and contains complex genome constituents. To assess global changes in gene expression patterns in the wheat life cycle, we conducted large-scale analysis of expressed sequence tags (ESTs) in common wheat. Ten wheat tissues were used to construct cDNA libraries: crown and root from 14-day-old seedlings; spikelet from early and late flowering stages; spike at the booting stage, heading date and flowering date; pistil at the heading date; and seeds at 10 and 30 days post-anthesis. Several thousand colonies were randomly selected from each of these 10 cDNA libraries and sequenced from both 5' and 3' ends. Consequently, a total of 116 232 sequences were accumulated and classified into 25 971 contigs based on sequence homology. By computing abundantly expressed ESTs, correlated expression patterns of genes across the tissues were identified. Furthermore, relationships of gene expression profiles among the 10 wheat tissues were inferred from global gene expression patterns. Genes with similar functions were grouped with one another by clustering gene expression profiles. This technique might enable estimation of the functions of anonymous genes. Multidimensional analysis of EST data that is analogous to the microarray experiments may offer new approaches to functional genomics of plants.  相似文献
5.
 疟蚊主要依靠嗅觉发现寄主。非洲疟蚊冈比亚按蚊Anopheles gambiae是一种嗜吸人血的疟疾传播媒介昆虫。该文作者基于其全基因组序列,采用RT-PCR和标准分子克隆技术获得2个嗅觉结合蛋白候选基因agLZ3788agLZ9988。测序分析结果表明,它们具有嗅觉结合蛋白的标志性结构域。进一步采用半定量RT-PCR技术研究了它们的空间表达型,结果发现它们不但在雌蚊触角中表达,也在其他部位(尤其是蚊虫足部)有强的表达。这一发现说明疟蚊嗅觉结合蛋白可能具有更广的功能,也为进一步重组表达和功能研究提供了重要依据。  相似文献
6.
To understand the molecular mechanism of ovule development, a MADS box gene,HoMADS 1, has been isolated from the ovule tissues of Hyacinthus. Sequence comparison showed that HoMADS 1 is highly homologous to both class C and D genes. Furthermore, phylogenetic analysis suggests that HoMADS 1 is most likely a class D MADS box gene. RNA hybridization revealed that HoMADS 1 was exclusively expressed in the ovules. Over-expressing HoMADS 1 in transgenic Arabidopsis plants produced ectopic carpelloid structures, including ovules, indicating that HoMADS 1 is involved in the determination of carpel and ovule identities. Interestingly, during in vitro flowering, no HoMADS 1 mRNA was detected in the floral tissues at high level hormones in the media. However, HoMADS 1 mRNA accumulated in the floral tissues when the regenerated flowers were transferred to the media containing low level hormones which could induce in vitro ovule formation. Our data suggest that the induction of HoMADS 1 by plant hormones may play important roles during ovule initiation and development in the regenerated flower. Whether HoMADS 1 expression is also regulated by cytokinin and auxin during ovule development in planta remains to be investigated.  相似文献
7.
The expression of endogenous LIM kinase 1 (LIMK1) protein was investigated in embryonic and adult mice using a rat monoclonal antibody (mAb), which recognizes specifically the PDZ domain of LIMK1 and not LIMK2. Immunoblotting analysis revealed widespread expression of LIMK1 existing as a 70-kDa protein in tissues and in cell lines, with a higher mass form (approximately 75 kDa) present in some tissues and cell lines. Smaller isoforms of approximately 50 kDa were also occasionally evident. Immunofluorescence analysis demonstrated LIMK1 subcellular localization at focal adhesions in fibroblasts as revealed by co-staining with actin, paxillin and vinculin in addition to perinuclear (Golgi) and occasional nuclear localization. Furthermore, an association between LIMK1 and paxillin but not vinculin was identified by co-immunoprecipitation analysis. LIMK1 is enriched in both axonal and dendritic growth cones of E18 rat hippocampal pyramidal neurons where it is found in punctae that extend far out into filopodia, as well as in a perinuclear region identified as Golgi. In situ, we identify LIMK1 protein expression in all embryonic and adult tissues examined, albeit at different levels and in different cell populations. The rat monoclonal LIMK1 antibody recognizes proteins of similar size in cell and tissue extracts from numerous species. Thus, LIMK1 is a widely expressed protein that exists as several isoforms.  相似文献
8.
查尔酮合成酶基因   总被引:8,自引:0,他引:8  
查尔酮合成酶基因是苯丙氨酸代谢途径中的关键基因,在类黄酮类物质合成中扮演着重要的角色,调控着色素合成、防御反应、植物育性等生理生化过程,对植物的生长发育起着至关重要的作用。现对查尔酮合成酶在苯丙氨酸代谢途径中的地位、基因表达特性、基因功能以及基因进化等方面的进展做一介绍。  相似文献
9.
Tissue distribution of the secretory protein, SPLUNC1, in the human fetus   总被引:7,自引:2,他引:5  
We previously identified a tissue-specific gene, short palate, lung, and nasal epithelium clone 1 (SPLUNC1), in nasopharyngeal epithelial tissues. SPLUNC1 was differentially expressed in nasopharyngeal carcinoma. Bioinformatic analysis revealed that SPLUNC1 has the bactericidal permeability-increasing protein/lipid-binding protein (BPI/LBP) domain and a 19 amino acid signal peptide, which suggest that it is a secretory protein. Its precise cellular localization in the respiratory tract is mainly in mucous cells and ducts of submucosal glands. However, little is known about its expression pattern in various human tissues. We generated a highly specific antibody and analyzed its distribution in the human fetus by immunohistochemistry to more precisely determine SPLUNC1 protein localization in human tissues. The results were further validated by RT-PCR. Our results showed that SPLUNC1 protein is expressed at not only the serous glands and epithelium of the upper respiratory tract and digestive tract, but also in the oculi of human embryos. Interestingly, we also found positive staining in fetus adipose tissue, a result not previously reported in studies of adult human tissues. Western blot analysis detected a 24 kDa SPLUNC1 protein in the compounds of nasopharyngeal secretions. This secretory protein was also detected in saliva and tears. Our research suggests that SPLUNC1 protein may not only be an antimicrobial peptide that plays an important role in the maintenance of homeostasis in the upper respiratory tract, oculi, and alimentary tract, it may also be important in the development and lipid metabolism of the adipose tissue.  相似文献
10.
以白洛克肉鸡 (EE)、中国丝羽乌骨鸡 (CC)、农大褐 (DD)和白来航 (AA) 4个纯种鸡为材料 ,进行 4× 4完全双列杂交 ,共得到 16种杂交组合。应用mRNA差异显示技术 (DDRT PCR)检测了 8周龄纯种和杂种鸡之间肝脏组织基因的差异表达。结果表明 ,在纯种和杂种间共有 8种 15类基因差异表达模式 ,杂种和纯种之间基因表达存在明显的差异。对各种基因差异表达模式与 10个肉用性状的杂种优势率进行相关分析发现 ,表达一致型P8(t1111)与肉用性状的杂种优势率相关不显著 (P >0 0 5) ,这说明杂种优势的形成与某些基因的差异表达有关 ;正交或反交特异表达型P4(t0 10 0、t0 0 10 )与 8周龄个体重、腿肌重、半净膛重、全净膛重相关显著 (P <0 0 5) ,与胸肌重相关极显著 (P <0 0 1) ;单亲特异表达型P1(t10 0 0、t0 0 0 1)与腹脂重相关显著 (P <0 0 5) ,与体斜长相关极显著 (P <0 0 1) ;双亲特异表达型P7(t10 0 1)与腿肌重、翅重、半净膛重、肌间脂宽的杂种优势率相关显著 (P <0 0 5) ;正交或反交单亲表达一致型P2 (t110 0、t0 0 11、t10 10、t0 10 1)与肌间脂宽的杂种优势率相关显著 (P <0 0 5) ;单亲表达一致型P5(t1110、t0 111)胫骨长的杂种优势率相关显著 (P <0 0 5)。  相似文献
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