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41.
Phosphate solubilization potential and stress tolerance of Eupenicillium parvum from tea soil 总被引:2,自引:0,他引:2
Eupenicillium parvum was recorded for first time during isolation of phosphate-solubilizing microorganisms from the tea rhizosphere. The fungus developed a phosphate solubilization zone on modified Pikovskaya agar, supplemented with tricalcium phosphate. Quantitative estimation of phosphate solubilization in Pikovskaya broth showed high solubilization of tricalcium phosphate and aluminium phosphate. The fungus also solubilized North Carolina rock phosphate and Mussoorie rock phosphate, and exhibited high levels of tolerance against desiccation, acidity, salinity, aluminium, and iron. Solubilization of inorganic phosphates by the fungus was also observed under high stress levels of aluminium, iron, and desiccation, though the significant decline in phosphate solubilization was marked in the presence of aluminium than iron. The fungal isolate showed 100 % identity with E. parvum strain NRRL 2095 ITS 1, 5.8S rRNA gene and ITS 2, complete sequence; and 28S rRNA gene, partial sequence. 相似文献
42.
Beaulieu F Ouellet C Ruediger EH Belema M Qiu Y Yang X Banville J Burke JR Gregor KR MacMaster JF Martel A McIntyre KW Pattoli MA Zusi FC Vyas D 《Bioorganic & medicinal chemistry letters》2007,17(5):1233-1237
We have recently identified BMS-345541 (1) as a highly selective and potent inhibitor of IKK-2 (IC50 = 0.30 microM), which however was considerably less potent against IKK-1 (IC50 = 4.0 microM). In order to further explore the SAR around the imidazoquinoxaline tricyclic structure of 1, we prepared a series of tetracyclic analogues (7, 13, and 18). The synthesis and biological activities of these potent IKK inhibitors are described. 相似文献
43.
Goodin JL Nellis DF Powell BS Vyas VV Enama JT Wang LC Clark PK Giardina SL Adamovicz JJ Michiel DF 《Protein expression and purification》2007,53(1):63-79
The F1-V vaccine antigen, protective against Yersinia pestis, exhibits a strong tendency to multimerize that affects larger-scale manufacture and characterization. In this work, the sole F1-V cysteine was replaced with serine by site-directed mutagenesis for characterization of F1-V non-covalent multimer interactions and protective potency without participation by disulfide-linkages. F1-V and F1-V(C424S) proteins were overexpressed in Escherichia coli, recovered using mechanical lysis/pH-modulation and purified from urea-solubilized soft inclusion bodies, using successive ion-exchange, ceramic hydroxyapatite, and size-exclusion chromatography. This purification method resulted in up to 2mg/g of cell paste of 95% pure, mono-disperse protein having < or =0.5 endotoxin units per mg by a kinetic chromogenic limulus amoebocyte lysate reactivity assay. Both F1-V and F1-V(C424S) were monomeric at pH 10.0 and progressively self-associated as pH conditions decreased to pH 6.0. Solution additives were screened for their ability to inhibit F1-V self-association at pH 6.5. An L-arginine buffer provided the greatest stabilizing effect. Conversion to >500-kDa multimers occurred between pH 6.0 and 5.0. Conditions for efficient F1-V adsorption to the cGMP-compatible alhydrogel adjuvant were optimized. Side-by-side evaluation for protective potency against subcutaneous plague infection in mice was conducted for F1-V(C424S) monomer; cysteine-capped F1-V monomer; cysteine-capped F1-V multimer; and a F1-V standard reported previously. After a two-dose vaccination with 2 x 20 microg of F1-V, respectively, 100%, 80%, 80%, and 70% of injected mice survived a subcutaneous lethal plague challenge with 10(8) LD(50)Y. pestis CO92. Thus, vaccination with F1-V monomer and multimeric forms resulted in significant, and essentially equivalent, protection. 相似文献
44.
Human ribosomal protein L13a is dispensable for canonical ribosome function but indispensable for efficient rRNA methylation 下载免费PDF全文
Chaudhuri S Vyas K Kapasi P Komar AA Dinman JD Barik S Mazumder B 《RNA (New York, N.Y.)》2007,13(12):2224-2237
Previously, we demonstrated that treatment of monocytic cells with IFN-gamma causes release of ribosomal protein L13a from the 60S ribosome and subsequent translational silencing of Ceruloplasmin (Cp) mRNA. Here, evidence using cultured cells demonstrates that Cp mRNA silencing is dependent on L13a and that L13a-deficient ribosomes are competent for global translational activity. Human monocytic U937 cells were stably transfected with two different shRNA sequences for L13a and clonally selected for more than 98% abrogation of total L13a expression. Metabolic labeling of these cells showed rescue of Cp translation from the IFN-gamma mediated translational silencing activity. Depletion of L13a caused significant reduction of methylation of ribosomal RNA and of cap-independent translation mediated by Internal Ribosome Entry Site (IRES) elements derived from p27, p53, and SNAT2 mRNAs. However, no significant differences in the ribosomal RNA processing, polysome formation, global translational activity, translational fidelity, and cell proliferation were observed between L13a-deficient and wild-type control cells. These results support the notion that ribosome can serve as a depot for releasable translation-regulatory factors unrelated to its basal polypeptide synthetic function. Unlike mammalian cells, the L13a homolog in yeast is indispensable for growth. Thus, L13a may have evolved from an essential ribosomal protein in lower eukaryotes to having a role as a dispensable extra-ribosomal function in higher eukaryotes. 相似文献
45.
46.
Raman Dhariwal Vijay Gahlaut Bhaganagare R. Govindraj Dharmendra Singh Saloni Mathur Shailendra Vyas Rajib Bandopadhyay Jitendra Paul Khurana Akhilesh Kumar Tyagi Kumble Vinod Prabhu Kunal Mukhopadhyay Harindra Singh Balyan Pushpendra Kumar Gupta 《Functional & integrative genomics》2015,15(2):233-245
47.
Han KP Zhu X Liu B Jeng E Kong L Yovandich JL Vyas VV Marcus WD Chavaillaz PA Romero CA Rhode PR Wong HC 《Cytokine》2011,56(3):804-810
IL-15, a promising cytokine for treating cancer and viral diseases, is presented in trans by the IL-15 receptor (IL-15R) alpha-chain to the IL-15Rβγc complex displayed on the surface of T cells and natural killer (NK) cells. We previously reported that an asparagine to aspartic acid substitution at amino acid 72 (N72D) of IL-15 provides a 4-5-fold increase in biological activity compared to the native molecule. In this report, we describe Chinese hamster ovary (CHO) cell expression of a soluble complex (IL-15 N72D:IL-15RαSu/Fc) consisting of the IL-15 N72D superagonist and a dimeric IL-15Rα sushi domain-IgG1 Fc fusion protein. A simple but readily scalable affinity and ion exchange chromatography method was developed to highly purify the complex having both IL-15 binding sites fully occupied. The immunostimulatory effects of this complex were confirmed using cell proliferation assays. Treatment of mice with a single intravenous dose of IL-15N72D:IL-15RαSu/Fc resulted in a significant increase in CD8+ T cells and NK cells that was not observed following IL-15 treatment. Pharmacokinetic analysis indicated that the complex has a 25-h half-life in mice which is considerably longer than <40-min half-life of IL-15. Thus, the enhanced activity of the IL-15N72D:IL-15RαSu/Fc complex is likely the result of the increased binding activity of IL-15N72D to IL-15Rβγc, optimized cytokine trans-presentation by the IL-15RαSu domain, the dimeric nature of the cytokine domain and its increased in vivo half-life compared to IL-15. These findings indicate that this IL-15 superagonist complex could serve as a superior immunostimulatory therapeutic agent. 相似文献
48.
Sargeant D Deverasetty S Luo Y Villahoz Baleta A Zobrist S Rathnayake V Russo JC Vyas J Muesing MA Schiller MR 《PloS one》2011,6(5):e20122
Many bioinformatic databases and applications focus on a limited domain of knowledge federating links to information in other databases. This segregated data structure likely limits our ability to investigate and understand complex biological systems. To facilitate research, therefore, we have built HIVToolbox, which integrates much of the knowledge about HIV proteins and allows virologists and structural biologists to access sequence, structure, and functional relationships in an intuitive web application. HIV-1 integrase protein was used as a case study to show the utility of this application. We show how data integration facilitates identification of new questions and hypotheses much more rapid and convenient than current approaches using isolated repositories. Several new hypotheses for integrase were created as an example, and we experimentally confirmed a predicted CK2 phosphorylation site. Weblink: [http://hivtoolbox.bio-toolkit.com]. 相似文献
49.
Females in various species typically avoid males infected with parasites, while parasite-free males advertise their status through conspicuous phenotypic traits. This process selects for heritable resistance and reduces direct exposure of the female to parasites. Coevolving parasites are likely to attempt to circumvent this obstacle. In this paper, we demonstrate a case of parasitic manipulation of host mate choice. We report that Toxoplasma gondii, a sexually transmitted infection of brown rats, enhances sexual attractiveness of infected males. Thus under some evolutionary niches, parasites can indeed manipulate host sexual signaling to their own advantage. 相似文献
50.
pSAT vectors: a modular series of plasmids for autofluorescent protein tagging and expression of multiple genes in plants 总被引:2,自引:0,他引:2
Tzfira T Tian GW Lacroix B Vyas S Li J Leitner-Dagan Y Krichevsky A Taylor T Vainstein A Citovsky V 《Plant molecular biology》2005,57(4):503-516
Autofluorescent protein tags represent one of the major and, perhaps, most powerful tools in modern cell biology for visualization
of various cellular processes in vivo. In addition, advances in confocal microscopy and the development of autofluorescent proteins with different excitation and
emission spectra allowed their simultaneous use for detection of multiple events in the same cell. Nevertheless, while autofluorescent
tags are widely used in plant research, the need for a versatile and comprehensive set of vectors specifically designed for
fluorescent tagging and transient and stable expression of multiple proteins in plant cells from a single plasmid has not
been met by either the industrial or the academic communities. Here, we describe a new modular satellite (SAT) vector system
that supports N- and C-terminal fusions to five different autofluorescent tags, EGFP, EYFP, Citrine-YFP, ECFP, and DsRed2.
These vectors carry an expanded multiple cloning site that allows easy exchange of the target genes between different autofluorescence
tags, and expression of the tagged proteins is controlled by constitutive promoters, which can be easily replaced with virtually
any other promoter of interest. In addition, a series of SAT vectors has been adapted for high throughput Gateway recombination
cloning. Furthermore, individual expression cassettes can be assembled into Agrobacterium binary plasmids, allowing efficient transient and stable expression of multiple autofluorescently tagged proteins from a
single vector following its biolistic delivery or Agrobacterium-mediated genetic transformation.
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献