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971.
972.
973.
The anonymous set of astronomical tables preserved in Paris, Bibliothèque nationale de France, MS lat. 10262, is the first set of displaced tables to be found in a medieval Latin text. These tables are a reworking of the standard Alfonsine tables and yield the same results. However, the mean motions are defined differently, the presentation of the tables is unprecedented, and some new functions are introduced for computing true planetary longitudes. The absence of any instructions as well as unusual technical terms in the headings make it difficult to appreciate the cleverness that went into the construction of these tables that are extant in a unique copy. In this article we provide a detailed analysis of these tables and their underlying parameters. The displaced tables are typical of a pervasive tendency in Islamic science to provide extensive and elegant numerical tables for the convenience of practitioners. The underlying astronomical theory is neither questioned nor affected. Edward S. Kennedy 相似文献
974.
Soler Artigas M Loth DW Wain LV Gharib SA Obeidat M Tang W Zhai G Zhao JH Smith AV Huffman JE Albrecht E Jackson CM Evans DM Cadby G Fornage M Manichaikul A Lopez LM Johnson T Aldrich MC Aspelund T Barroso I Campbell H Cassano PA Couper DJ Eiriksdottir G Franceschini N Garcia M Gieger C Gislason GK Grkovic I Hammond CJ Hancock DB Harris TB Ramasamy A Heckbert SR Heliövaara M Homuth G Hysi PG James AL Jankovic S Joubert BR Karrasch S Klopp N Koch B Kritchevsky SB Launer LJ Liu Y Loehr LR 《Nature genetics》2011,43(11):1082-1090
Pulmonary function measures reflect respiratory health and are used in the diagnosis of chronic obstructive pulmonary disease. We tested genome-wide association with forced expiratory volume in 1 second and the ratio of forced expiratory volume in 1 second to forced vital capacity in 48,201 individuals of European ancestry with follow up of the top associations in up to an additional 46,411 individuals. We identified new regions showing association (combined P < 5 × 10(-8)) with pulmonary function in or near MFAP2, TGFB2, HDAC4, RARB, MECOM (also known as EVI1), SPATA9, ARMC2, NCR3, ZKSCAN3, CDC123, C10orf11, LRP1, CCDC38, MMP15, CFDP1 and KCNE2. Identification of these 16 new loci may provide insight into the molecular mechanisms regulating pulmonary function and into molecular targets for future therapy to alleviate reduced lung function. 相似文献
975.
Biased binding of class IA phosphatidyl inositol 3-kinase subunits to inducible costimulator (CD278)
Acosta YY Zafra MP Ojeda G Bernardone IS Dianzani U Portolés P Rojo JM 《Cellular and molecular life sciences : CMLS》2011,68(18):3065-3079
To better understand T lymphocyte costimulation by inducible costimulator (ICOS; H4; CD278), we analyzed proteins binding
to ICOS peptides phosphorylated at the Y191MFM motif. Phosphorylated ICOS binds class IA phosphatidyl inositol 3-kinase (PI3-K) p85α, p50-55α and p85β regulatory subunits
and p110α, p110δ and p110β catalytic subunits. Intriguingly, T cells expressed high levels of both p110α or p110δ catalytic
subunits, yet ICOS peptides, cell surface ICOS or PI3-kinase class IA regulatory subunits preferentially coprecipitated p110α
catalytic subunits. Silencing p110α or p110δ partially inhibited Akt/PKB activation induced by anti-CD3 plus anti-ICOS antibodies.
However, silencing p110α enhanced and silencing p110δ inhibited Erk activation. Both p110α- and p110δ-specific inhibitors
blocked cytokine secretion induced by TCR/CD3 activation with or without ICOS costimulus, but only p110α inhibitors blocked
ICOS-induced cell elongation. Thus, p110α and p110δ are essential to optimal T cell activation, but their abundance and activity
differentially tune up distinct ICOS signaling pathways. 相似文献
976.
Membrane vesicles, current state-of-the-art: emerging role of extracellular vesicles 总被引:4,自引:3,他引:1
György B Szabó TG Pásztói M Pál Z Misják P Aradi B László V Pállinger E Pap E Kittel A Nagy G Falus A Buzás EI 《Cellular and molecular life sciences : CMLS》2011,68(16):2667-2688
Release of membrane vesicles, a process conserved?in both?prokaryotes and eukaryotes, represents an evolutionary link, and suggests essential functions of a dynamic extracellular vesicular compartment (including exosomes, microparticles or microvesicles and apoptotic bodies). Compelling evidence supports the significance of this compartment in a broad range of physiological and pathological processes. However, classification of membrane vesicles, protocols of their isolation and detection, molecular details of vesicular release, clearance and biological functions are still under intense investigation. Here, we give a comprehensive overview of extracellular vesicles. After discussing the technical pitfalls and potential artifacts of the rapidly emerging field, we compare results from meta-analyses of published proteomic studies on membrane vesicles. We also summarize clinical implications of membrane vesicles. Lessons from this compartment challenge current paradigms concerning the mechanisms of intercellular communication and immune regulation. Furthermore, its clinical implementation may open new perspectives in translational medicine both in diagnostics and therapy. 相似文献
977.
The structure of grassland communities can vary widely in response to heterogeneous habitat variables. In this study we document plant communities, soil types, and site characteristics for 12 Palouse prairie remnants in southeastern Washington and northern Idaho. We used general linear models to test the predictive value of 6 biophysical variables (slope, aspect, distance from edge, edge type, vegetation structure, and soil type) on 3 plant community metrics: species richness, Simpson’s diversity index, and the dominance of exotic species. From full models including all variables, we used Akaike’s information criterion (AIC) to select the best model for each metric. Aspect and vegetation structure were significant predictors of species richness ( R 2 = 0.08) and diversity ( R 2 = 0.09), while aspect, soil type, distance from edge, and edge type (type of adjacent matrix habitat) influenced the dominance of exotic species ( R 2 = 0.28). Additional soil sampling determined that the depth to a restrictive layer also had significant impacts on the dominance of exotic species ( R 2 = 0.31). This study confirms that biophysical characteristics influence Palouse prairie plant communities and may help set research and conservation priorities for isolated and uninventoried remnants. 相似文献
978.
António Rua 《Journal of forecasting》2011,30(7):666-678
It has been acknowledged that wavelets can constitute a useful tool for forecasting in economics. Through a wavelet multi‐resolution analysis, a time series can be decomposed into different timescale components and a model can be fitted to each component to improve the forecast accuracy of the series as a whole. Up to now, the literature on forecasting with wavelets has mainly focused on univariate modelling. On the other hand, in a context of growing data availability, a line of research has emerged on forecasting with large datasets. In particular, the use of factor‐augmented models have become quite widespread in the literature and among practitioners. The aim of this paper is to bridge the two strands of the literature. A wavelet approach for factor‐augmented forecasting is proposed and put to test for forecasting GDP growth for the major euro area countries. The results show that the forecasting performance is enhanced when wavelets and factor‐augmented models are used together. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
979.
Adrianto I Wen F Templeton A Wiley G King JB Lessard CJ Bates JS Hu Y Kelly JA Kaufman KM Guthridge JM Alarcón-Riquelme ME;BIOLUPUS GENLES Networks Anaya JM Bae SC Bang SY Boackle SA Brown EE Petri MA Gallant C Ramsey-Goldman R Reveille JD Vila LM Criswell LA Edberg JC Freedman BI Gregersen PK Gilkeson GS Jacob CO James JA Kamen DL Kimberly RP Martin J Merrill JT Niewold TB Park SY Pons-Estel BA Scofield RH Stevens AM Tsao BP Vyse TJ Langefeld CD Harley JB Moser KL Webb CF Humphrey MB 《Nature genetics》2011,43(3):253-258
Systemic lupus erythematosus (SLE, MIM152700) is an autoimmune disease characterized by self-reactive antibodies resulting in systemic inflammation and organ failure. TNFAIP3, encoding the ubiquitin-modifying enzyme A20, is an established susceptibility locus for SLE. By fine mapping and genomic re-sequencing in ethnically diverse populations, we fully characterized the TNFAIP3 risk haplotype and identified a TT>A polymorphic dinucleotide (deletion T followed by a T to A transversion) associated with SLE in subjects of European (P = 1.58 × 10(-8), odds ratio = 1.70) and Korean (P = 8.33 × 10(-10), odds ratio = 2.54) ancestry. This variant, located in a region of high conservation and regulatory potential, bound a nuclear protein complex composed of NF-κB subunits with reduced avidity. Further, compared with the non-risk haplotype, the haplotype carrying this variant resulted in reduced TNFAIP3 mRNA and A20 protein expression. These results establish this TT>A variant as the most likely functional polymorphism responsible for the association between TNFAIP3 and SLE. 相似文献
980.
The genome of the mesopolyploid crop species Brassica rapa 总被引:21,自引:0,他引:21
Wang X Wang H Wang J Sun R Wu J Liu S Bai Y Mun JH Bancroft I Cheng F Huang S Li X Hua W Wang J Wang X Freeling M Pires JC Paterson AH Chalhoub B Wang B Hayward A Sharpe AG Park BS Weisshaar B Liu B Li B Liu B Tong C Song C Duran C Peng C Geng C Koh C Lin C Edwards D Mu D Shen D Soumpourou E Li F Fraser F Conant G Lassalle G King GJ Bonnema G Tang H Wang H Belcram H Zhou H Hirakawa H Abe H Guo H Wang H Jin H Parkin IA Batley J Kim JS Just J Li J Xu J Deng J Kim JA Li J Yu J Meng J Wang J Min J 《Nature genetics》2011,43(10):1035-1039
We report the annotation and analysis of the draft genome sequence of Brassica rapa accession Chiifu-401-42, a Chinese cabbage. We modeled 41,174 protein coding genes in the B. rapa genome, which has undergone genome triplication. We used Arabidopsis thaliana as an outgroup for investigating the consequences of genome triplication, such as structural and functional evolution. The extent of gene loss (fractionation) among triplicated genome segments varies, with one of the three copies consistently retaining a disproportionately large fraction of the genes expected to have been present in its ancestor. Variation in the number of members of gene families present in the genome may contribute to the remarkable morphological plasticity of Brassica species. The B. rapa genome sequence provides an important resource for studying the evolution of polyploid genomes and underpins the genetic improvement of Brassica oil and vegetable crops. 相似文献