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991.
The phenyldi(2-thienyl)phosphine (PhPTh2) complexes [Os3(CO)12−n(PhPTh2)n] (n = 1-3) (1-3) have been prepared. Thermolysis of 1 and either 2 or 3 in octane affords carbon-hydrogen bond activation products [Os3(CO)9{μ3-PPhTh(C4H2S)}(μ-H)] (4) and [Os3(CO)8(PPhTh2){μ3-PPhTh(C4H2S)}(μ-H)] (5), respectively. Both exist as isomeric mixtures differing in the relative positions of phenyl and thienyl substituents with respect to the triosmium centre. The nature of the process has been confirmed by a single crystal X-ray diffraction analysis of 4. 相似文献
992.
Molecular Ecology Resources Primer Development Consortium An J Bechet A Berggren A Brown SK Bruford MW Cai Q Cassel-Lundhagen A Cezilly F Chen SL Cheng W Choi SK Ding XY Fan Y Feldheim KA Feng ZY Friesen VL Gaillard M Galaraza JA Gallo L Ganeshaiah KN Geraci J Gibbons JG Grant WS Grauvogel Z Gustafsson S Guyon JR Han L Heath DD Hemmilä S Hogan JD Hou BW Jakse J Javornik B Kaňuch P Kim KK Kim KS Kim SG Kim SI Kim WJ Kim YK Klich MA Kreiser BR Kwan YS Lam AW Lasater K Lascoux M Lee H Lee YS Li DL 《Molecular ecology resources》2010,10(2):404-408
This article documents the addition of 411 microsatellite marker loci and 15 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Acanthopagrus schlegeli, Anopheles lesteri, Aspergillus clavatus, Aspergillus flavus, Aspergillus fumigatus, Aspergillus oryzae, Aspergillus terreus, Branchiostoma japonicum, Branchiostoma belcheri, Colias behrii, Coryphopterus personatus, Cynogolssus semilaevis, Cynoglossus semilaevis, Dendrobium officinale, Dendrobium officinale, Dysoxylum malabaricum, Metrioptera roeselii, Myrmeciza exsul, Ochotona thibetana, Neosartorya fischeri, Nothofagus pumilio, Onychodactylus fischeri, Phoenicopterus roseus, Salvia officinalis L., Scylla paramamosain, Silene latifo, Sula sula, and Vulpes vulpes. These loci were cross-tested on the following species: Aspergillus giganteus, Colias pelidne, Colias interior, Colias meadii, Colias eurytheme, Coryphopterus lipernes, Coryphopterus glaucofrenum, Coryphopterus eidolon, Gnatholepis thompsoni, Elacatinus evelynae, Dendrobium loddigesii Dendrobium devonianum, Dysoxylum binectariferum, Nothofagus antarctica, Nothofagus dombeyii, Nothofagus nervosa, Nothofagus obliqua, Sula nebouxii, and Sula variegata. This article also documents the addition of 39 sequencing primer pairs and 15 allele specific primers or probes for Paralithodes camtschaticus. 相似文献
993.
Silencing viral infection 总被引:1,自引:0,他引:1
994.
Bioinspired fibrous materials that span the nano-to-meso scales have potentially broad applications in nanobiotechnology; for instance, as scaffolds in 3D cell culture and tissue engineering, and as templates for the assembly of other polymer and inorganic materials. The field is burgeoning, and this review is necessarily focused. It centres on recent developments in the design of peptide-based fibres and particularly those using the alpha-helix and the collagen triple helix as building blocks for self-assembly. Advances include new designs in both categories, the assembly of more-complex topologies using fibres themselves as building blocks, and the decoration of the assembled materials with functional moieties. 相似文献
995.
996.
Gregory J. Dick Melissa B. Duhaime Jacob T. Evans Reagan M. Errera Casey M. Godwin Jenan J. Kharbush Helena S. Nitschky McKenzie A. Powers Henry A. Vanderploeg Kathryn C. Schmidt Derek J. Smith Colleen E. Yancey Claire C. Zwiers Vincent J. Denef 《Environmental microbiology》2021,23(12):7278-7313
Microcystis is a cyanobacterium that forms toxic blooms in freshwater ecosystems around the world. Biological variation among taxa within the genus is apparent through genetic and phenotypic differences between strains and via the spatial and temporal distribution of strains in the environment, and this fine-scale diversity exerts strong influence over bloom toxicity. Yet we do not know how varying traits of Microcystis strains govern their environmental distribution, the tradeoffs and links between these traits, or how they are encoded at the genomic level. Here we synthesize current knowledge on the importance of diversity within Microcystis and on the genes and traits that likely underpin ecological differentiation of taxa. We briefly review spatial and environmental patterns of Microcystis diversity in the field and genetic evidence for cohesive groups within Microcystis. We then compile data on strain-level diversity regarding growth responses to environmental conditions and explore evidence for variation of community interactions across Microcystis strains. Potential links and tradeoffs between traits are identified and discussed. The resulting picture, while incomplete, highlights key knowledge gaps that need to be filled to enable new models for predicting strain-level dynamics, which influence the development, toxicity and cosmopolitan nature of Microcystis blooms. 相似文献
997.
Competitive Mechanisms for Inhibition of Sulfate Reduction and Methane Production in the Zone of Ferric Iron Reduction in Sediments 总被引:12,自引:18,他引:12 下载免费PDF全文
Mechanisms for inhibition of sulfate reduction and methane production in the zone of Fe(III) reduction in sediments were investigated. Addition of amorphic iron(III) oxyhydroxide to sediments in which sulfate reduction was the predominant terminal electron-accepting process inhibited sulfate reduction 86 to 100%. The decrease in electron flow to sulfate reduction was accompanied by a corresponding increase in electron flow to Fe(III) reduction. In a similar manner, Fe(III) additions also inhibited methane production in sulfate-depleted sediments. The inhibition of sulfate reduction and methane production was the result of substrate limitation, because the sediments retained the potential for sulfate reduction and methane production in the presence of excess hydrogen and acetate. Sediments in which Fe(III) reduction was the predominant terminal electron-accepting process had much lower concentrations of hydrogen and acetate than sediments in which sulfate reduction or methane production was the predominant terminal process. The low concentrations of hydrogen and acetate in the Fe(III)-reducing sediments were the result of metabolism by Fe(III)-reducing organisms of hydrogen and acetate at concentrations lower than sulfate reducers or methanogens could metabolize them. The results indicate that when Fe(III) is in a form that Fe(III)-reducing organisms can readily reduce, Fe(III)-reducing organisms can inhibit sulfate reduction and methane production by outcompeting sulfate reducers and methanogens for electron donors. 相似文献
998.
Six1 is required for the early organogenesis of mammalian kidney 总被引:12,自引:0,他引:12
999.
1000.
Reassessing Ethnic Differences in Mean BMI and Changes Between 2007 and 2013 in English Children 下载免费PDF全文