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Veena Jain Nisha Garg H. S. Nainawatee 《Journal of plant biochemistry and biotechnology.》1992,1(1):23-26
Rhizospheric application of nod regulators influenced the nodulation status, nodule efficiency and partitioning of assimilated CO2 in Pisum sativum-Rhizobium leguminosarum symbiosis. Depending upon the plant growth stage, naringenin and flavone enhanced nodule number (22.8–87.6%), nodule weight (19.2–35.2%) and nitrogenase activity (17.8–108.6%). Syringaldehyde had negative effect on various parameters of symbiosis. Proportion of 14C-assimilates was higher in nodules of plants from naringenin and flavone treatments as compared to the control or syringaldehyde treatments. The enhanced nodule efficiency in naringenin and flavone treatments was reflected in the increased N content (12.7–50.4%) and biomass (4.3–35.1%) of plants. 相似文献
874.
XK469 is an investigational anticancer agent that exhibits antiproliferative activity in tumor-bearing animal models. We examined the drug-action profile of this agent at the molecular level regarding alterations induced in gene expression and proteins in HCT-116 human colon adenocarcinoma cells. We used a unique cDNA microarray (GeneMap(TM) Cancerarray) comprising 1152 human tumor-related genes and 2-D gel electrophoresis, respectively, following a 24-hour exposure to a drug concentration that killed a two-log fraction of HCT-116 clonogenic cells. Functional gene cluster profile (FGCP) analysis of the 71 out of 1152 genes that displayed a >2-fold increase or decrease in expression (over untreated control) identified a drug-specific involvement of the MAPK signal transduction pathway. MAPK signaling together with the involvement of ubiquitin proteins from 2-D gel electrophoresis suggest a novel drug-action profile at the molecular level for the in vitro antiproliferative activity of XK469. 相似文献
875.
Arivalagan Sivaranjani Thomas Nisha Susan Chandrasekaran Balaji Mani Vijay Siddique Aktarul Islam Kuppsamy Thayalan Namasivayam Nalini 《Molecular and cellular biochemistry》2022,477(1):329-330
Molecular and Cellular Biochemistry - 相似文献
876.
Valerie J. Klema Mengyi Ye Aditya Hindupur Tadahisa Teramoto Keerthi Gottipati Radhakrishnan Padmanabhan Kyung H. Choi 《PLoS pathogens》2016,12(2)
Flavivirus nonstructural protein 5 (NS5) consists of methyltransferase (MTase) and RNA-dependent RNA polymerase (RdRp) domains, which catalyze 5’-RNA capping/methylation and RNA synthesis, respectively, during viral genome replication. Although the crystal structure of flavivirus NS5 is known, no data about the quaternary organization of the functional enzyme are available. We report the crystal structure of dengue virus full-length NS5, where eight molecules of NS5 are arranged as four independent dimers in the crystallographic asymmetric unit. The relative orientation of each monomer within the dimer, as well as the orientations of the MTase and RdRp domains within each monomer, is conserved, suggesting that these structural arrangements represent the biologically relevant conformation and assembly of this multi-functional enzyme. Essential interactions between MTase and RdRp domains are maintained in the NS5 dimer via inter-molecular interactions, providing evidence that flavivirus NS5 can adopt multiple conformations while preserving necessary interactions between the MTase and RdRp domains. Furthermore, many NS5 residues that reduce viral replication are located at either the inter-domain interface within a monomer or at the inter-molecular interface within the dimer. Hence the X-ray structure of NS5 presented here suggests that MTase and RdRp activities could be coordinated as a dimer during viral genome replication. 相似文献
877.
Sunny Jithin S. Nisha Khairun Natarajan Anuradha Saleena Lilly M. 《Extremophiles : life under extreme conditions》2021,25(4):319-325
Extremophiles - Biocatalysts provide many advantages over the traditional chemically assisted processes prevalent in industries. Consequently, the search for novel enzymes has increased over the... 相似文献
878.
Summary 1. In the teleostTilapia mossambica (Peters), new crops of oocytes arise from nests of cells of the germinal epithelium as well as from the epithelial strands ramifying into the ovocoel.2. There is no evidence to indicate that degenerating follicle cells form a source for a new crop of oocytes.3. After one spawning is over, the follicular layer of the mature unspawned ova alone undergo atresia.4. Neither immature oocytes nor oocytes in the growth stages undergo degeneration.5. The occurrence of immature, maturing, and fully ripe ova in the ovary at a particular time account for asynchronism inTilapia mossambica.
Origine des poussées ovocytaires chezTilapia mossambica
Extrait L'ovaire deTilapia mossambica a été étudié dans le but de préciser l'origine des poussées ovocytaires. Après la ponte l'ovaire n'est pas vide pour autant, et il y subsiste des ovocytes à tous les stades du développement. Les replis de l'épithélium germinatif et les tractus épithéliaux ramifiés contiennent des flots de cellules qui produisent des ovogonies primaires, lesquelles se transforment en ovocytes et en cellules folliculaires. Il ne semble pas qu'une nouvelle poussée ovocytaire puisse se faire à partir des résidus des follicules des ovocytes atrétiques. Seuls les ovules mûrs non évacués par la ponte subissent une atrésie et se résorbent; les ovocytes immatures ou en voie de croissance ne dégénèrent pas. L'asynchronisme deT. mossambica se traduit par la présence simultanée, dans l'ovaire, d'ovocytes à tous les stades de croissance et de maturation.相似文献
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Nisha K. Duggal Angela Bosco-Lauth Richard A. Bowen Sarah S. Wheeler William K. Reisen Todd A. Felix Brian R. Mann Hannah Romo Daniele M. Swetnam Alan D. T. Barrett Aaron C. Brault 《PLoS neglected tropical diseases》2014,8(10)
West Nile virus (WNV) has been maintained in North America in enzootic cycles between mosquitoes and birds since it was first described in North America in 1999. House sparrows (HOSPs; Passer domesticus) are a highly competent host for WNV that have contributed to the rapid spread of WNV across the U.S.; however, their competence has been evaluated primarily using an early WNV strain (NY99) that is no longer circulating. Herein, we report that the competence of wild HOSPs for the NY99 strain has decreased significantly over time, suggesting that HOSPs may have developed resistance to this early WNV strain. Moreover, recently isolated WNV strains generate higher peak viremias and mortality in contemporary HOSPs compared to NY99. These data indicate that opposing selective pressures in both the virus and avian host have resulted in a net increase in the level of host competence of North American HOSPs for currently circulating WNV strains. 相似文献