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21.
22.
The purpose of the present study was to determine whether zinc and calcium could interact at the tissue level. In the first
part of the study, adult rats were injected with ZnCl2 dissolved in a physiological saline solution to determine the effects of Zn on Ca levels in various tissues. In the second
part of the study, weaned rats (at day 22 postnatally) were fed a diet supplemented with Zn until day 50 and were then sacrificed.
In both instances, blood, brain, heart, liver, and skeletal muscle were taken and analyzed. In the Zn-injected group, the
brain, heart, and liver showed no interaction between Zn and Ca. The skeletal muscle, in contrast, showed a decrease in Ca
in the homogenate, whereas Zn contents showed a significant increase at the sarcoplasmic reticulum (SR). Likewise, in the
Zn-supplemented group, the Zn content of the SR vesicle of the skeletal muscle showed an increase, whereas Ca content of the
pellet (14,000 g), which contains cell debris, nucleus, mitochondria, and SR vesicles of this group, showed a decrease. Current
findings suggest antagonistic effects between Zn and Ca on this tissue. Zn may play a critical role in cellular function through
the alteration of itnracellular distribution of Ca in skeletal muscle. 相似文献
23.
Members of the casein kinase 1 (CK1) family are evolutionarily conserved eukaryotic protein kinases involved in various cellular, physiological, and developmental processes in yeast. However, the biological roles of CK1 members in plants are poorly understood. Here, we report that an Arabidopsis CK1 member named casein kinase 1-like 8 (CKL8) was ubiquitously expressed in all plant organs, mainly in the stems of seedlings according to quantitative real-time PCR. Western blotting showed a remarkable expression of the AtCKL8 gene in transgenic plants induced by high salinity. A histochemical assay of AtCKL8 promoter::GUS expression revealed that the AtCKL8 promoter is very active in both seedlings and adult plants subjected to the salinity stress, while no GUS activity was detectable in all the transgenic plants grown under normal conditions. In a subcellular distribution analysis, the AtCKL8-GFP fusion protein was localized mainly in the cell membrane. AtCKL8-overexpressing transgenic plants showed an insensitivity to high salinity and an early flowering phenotype. Overall, these findings suggest that AtCKL8 plays a positive role in NaCl signaling and improves salt stress tolerance in transgenic Arabidopsis. 相似文献
24.
The expression of the genes for two types of myrosinase (EC 3.2.3.1), designated MA and MB, during embryo and seedling development was investigated in Sinapis alba L. by in-situ and RNA slot-blot analyses. The expression of MA and MB genes followed similar temporal profiles during embryogenesis, but MB mRNA was present in considerably higher amounts than MA mRNA. In the embryo, both MA and MB genes are activated in cotyledons and axis. The MB genes are preferentially expressed in the cotyledons whereas MA genes are preferentially expressed in the axis. In the developing seedling, MA mRNA was not present in the organs investigated. By contrast, MB mRNA was found in appreciable amounts in hypocotyls, cotyledons and developing leaves. The MB genes seem to be activated preferentially in tissues undergoing rapid cell division and — or cell expansion.Abbreviations DAP
days after pollination
- MA, MB
A type, B type myrosinases in Sinapis alba
Anna-Stina Höglund (Uppsala Genetic Center) is gratefully acknowledged for valuable discussion, Anders Gobl (Department of Immunology, Uppsala University) for kindly advice with the labeling of probes and Qingzhu Zhai (Department of Pharmaceutical Biosciences, Uppsala University) for help with seed harvest. This work was supported by grants from the Swedish Research Council for Forestry and Agriculture. 相似文献
25.
《Molecular & cellular proteomics : MCP》2022,21(11):100418
Importin β1 (KPNB1) is a nucleocytoplasmic transport factor with critical roles in both cytoplasmic and nucleocytoplasmic transport, hence there is keen interest in the characterization of its subcellular interactomes. We found limited efficiency of BioID in the detection of importin complex cargos and therefore generated a highly specific and sensitive anti-KPNB1 monoclonal antibody to enable biotinylation by antibody recognition analysis of importin β1 interactomes. The monoclonal antibody recognizes an epitope comprising residues 301-320 of human KPBN1 and strikingly is highly specific for cytoplasmic KPNB1 in diverse applications, with little reaction with KPNB1 in the nucleus. Biotinylation by antibody recognition with this novel antibody revealed numerous new interactors of importin β1, expanding the KPNB1 interactome to cytoplasmic and signaling complexes that highlight potential new functions for the importins complex beyond nucleocytoplasmic transport. Data are available via ProteomeXchange with identifier PXD032728. 相似文献
26.
M. J. Higgins D. Loiselle T. A. Haystead L. M. Graves 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):850-857
We investigated the interacting proteins and intracellular localization of CTP synthetase 1 (CTPS1) in mammalian cells. CTPS1 interacted with a GST- peptidyl prolyl isomerase, Pin1 fusion (GST-Pin1) in a Ser 575 (S575) phosphorylation-dependent manner. Immunoprecipitation experiments demonstrated that CTPS1 also bound tubulin, and thirteen additional coimmunoprecipitating proteins were identified by mass spectrometry. Immunolocalization experiments showed that tubulin and CTPS1 colocalized subcellularly. Taxol treatment enhanced this but cotreatment of cells with the CTPS inhibitor, cyclopentenyl cytosine (CPEC), and taxol failed to disrupt the colocalization. Thus, these studies provide novel information on the potential interacting proteins that may regulate CTPS1 function or intracellular localization. 相似文献
27.
Human epidermoid carcinoma (HEp-3) cells are highly tumorigenic and metastatic in vivo, but their metastatic phenotype is progressively and uniquely lost upon serial passage in vitro. The nonmetastatic phenotype is fully reversible to the highly metastatic state when HEp-3 cells are passaged back in vivo. To study the complex process of metastasis and its possible negative regulation by specific gene products, the expression of specific proteins between the highly metastatic and nonmetastatic HEp-3 cells was investigated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and subsequent computer assisted analyses. Concomitant with the in vitro loss of metastatic potential of HEp-3 cells is the elevated expression of a subset of low abundance proteins detectable in 2D-PAGE but not apparent in high resolution one dimensional PAGE. When the HEp-3 cells revert to the metastatic state, the expression of these proteins declines. The increased abundance of four distinct proteins directly correlates with the loss of the metastatic phenotype: two of the four proteins are associated with isolated cellular membranes (36kD, pl 5.7; 22kDa, pl 5.6), on protein fractionates with the cytoplasm (65kD, pl 6.2), and one protein is enriched in the nuclei fraction (32kD, pl 5.8). These data indicate that computer-assisted analysis of highly sensitive, large-format, 2D-PAGE can be used to identify specific proteins in subcellular compartments that are candidates for negative regulators of the metastatic process. © 1993 Wiley-Liss, Inc. 相似文献
28.
An oxidative and salinity stress induced peroxisomal ascorbate peroxidase from Avicennia marina: Molecular and functional characterization 总被引:1,自引:0,他引:1
Kumaresan Kavitha Gayatri Venkataraman Ajay Parida 《Plant Physiology and Biochemistry》2008,46(8-9):794-804
APX (EC, 1.11.1.11) has a key role in scavenging ROS and in protecting cells against their toxic effects in algae and higher plants. A cDNA encoding a peroxisomal ascorbate peroxidase, Am-pAPX1, was isolated from salt stressed leaves of Avicennia marina (Forsk.) Vierh. by EST library screening and its expression in the context of various environmental stresses was investigated. Am-pAPX1 contains an ORF of 286 amino acids coding for a 31.4kDa protein. The C-terminal region of the Am-pAPX1 ORF has a putative transmembrane domain and a peroxisomal targeting signal (RKKMK), suggesting peroxisomal localization. The peroxisomal localization of Am-pAPX1 was confirmed by stable transformation of the GFP-(Ala)(10)-Am-pAPX1 fusion in tobacco. RNA blot analysis revealed that Am-pAPX1 is expressed in response to salinity (NaCl) and oxidative stress (high intensity light, hydrogen peroxide application and excess iron). The isolated genomic clone of Am-pAPX1 was found to contain nine exons. A fragment of 1616bp corresponding to the 5' upstream region of Am-pAPX1 was isolated by TAIL-PCR. In silico analysis of this sequence reveals the presence of putative light and abiotic stress regulatory elements. 相似文献
29.
A. V. Bol’shakova O. A. Petukhova G. P. Pinaev K. -E. Magnusson 《Cell and Tissue Biology》2009,3(2):188-197
α-Actinin 1 and α-actinin 4 are actin-binding proteins with shared structural functions that are responsible for the regulation of several processes in the cell. Based on previous data on the different distribution of these proteins in the nucleus and cytoplasm, we have studied in detail the presence of α-actinin 1 and α-actinin 4 in subcellular fractions in the A431 cells spread on fibronectin. The detection of α-actinins in some particular fractions has been shown to depend on the method of lysis, as well as whether the preliminary low-temperature freezing of cells was used. The application of various fractionation methods has allowed us to conclude that α-actinin 4 is present in all cytoplasmic and nuclear subfractions, whereas, in addition to in the cytoplasm, α-actinin 1 can also be revealed in the nuclear envelope fraction. 相似文献
30.
We have tested the effect of alkaloids (cocaine, morphine) and enkephalins on neutral endopeptidase of peripheral blood mononuclear cells activated by lectins. When treated with concanavalin A and cocaine, peripheral blood mononuclear cells showed an enhanced activity (+110 per cent) of the membrane neutral endopeptidase, which was not related to the expression of the common acute lymphoblastic leukemia antigen at the cell surface, although both molecules have the identical amino acid sequence. Phytohemagglutinin-P, morphine and synthetic enkephalins did not induce the activity of neutral endopeptidase nor the expression of common acute lymphoblastic leukemia antigen. Our findings suggested that the drugs of abuse, cocaine and morphine, affected specific membrane constituents without altering proliferation, subcellular localization of membrane enzymes or the surface immune phenotype of peripheral blood mononuclear cells. 相似文献