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Thibault ST Singer MA Miyazaki WY Milash B Dompe NA Singh CM Buchholz R Demsky M Fawcett R Francis-Lang HL Ryner L Cheung LM Chong A Erickson C Fisher WW Greer K Hartouni SR Howie E Jakkula L Joo D Killpack K Laufer A Mazzotta J Smith RD Stevens LM Stuber C Tan LR Ventura R Woo A Zakrajsek I Zhao L Chen F Swimmer C Kopczynski C Duyk G Winberg ML Margolis J 《Nature genetics》2004,36(3):283-287
With the availability of complete genome sequence for Drosophila melanogaster, one of the next strategic goals for fly researchers is a complete gene knockout collection. The P-element transposon, the workhorse of D. melanogaster molecular genetics, has a pronounced nonrandom insertion spectrum. It has been estimated that 87% saturation of the approximately 13,500-gene complement of D. melanogaster might require generating and analyzing up to 150,000 insertions. We describe specific improvements to the lepidopteran transposon piggyBac and the P element that enabled us to tag and disrupt genes in D. melanogaster more efficiently. We generated over 29,000 inserts resulting in 53% gene saturation and a more diverse collection of phenotypically stronger insertional alleles. We found that piggyBac has distinct global and local gene-tagging behavior from that of P elements. Notably, piggyBac excisions from the germ line are nearly always precise, piggyBac does not share chromosomal hotspots associated with P and piggyBac is more effective at gene disruption because it lacks the P bias for insertion in 5' regulatory sequences. 相似文献
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L. Robert 《Cellular and molecular life sciences : CMLS》1981,37(10):1055-1058
Conclusion The brief summary of our present knowledge on the aging of intercellular matrix macromolecules shows the progress which has been made since the original important discovery of Verzár, but it also points out the very considerable gaps which still have to be filled by continued research efforts in this theoretically and practically important area. It is no secret to anyone that most of the disabling and killing diseases of advanced societies concern connective tissues: arteriosclerosis, diabetes, pulmonary obstructive lung diseases, osteoarticular diseases and cancer itself are all age-dependent, so-called aging diseases. The interaction between intercellular matrix and cancer cells plays an important role in the spreading of the tumors. For these other major diseases, the direct involvement of intercellular matrix is well documented. It is therefore hoped that a better grasp of the basic mechanisms involved in these diseases will help us to understand the difference between pathology and aging per se. 相似文献
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Insertional mutagenesis in zebrafish rapidly identifies genes essential for early vertebrate development 总被引:21,自引:0,他引:21
Golling G Amsterdam A Sun Z Antonelli M Maldonado E Chen W Burgess S Haldi M Artzt K Farrington S Lin SY Nissen RM Hopkins N 《Nature genetics》2002,31(2):135-140
To rapidly identify genes required for early vertebrate development, we are carrying out a large-scale, insertional mutagenesis screen in zebrafish, using mouse retroviral vectors as the mutagen. We will obtain mutations in 450 to 500 different genes--roughly 20% of the genes that can be mutated to produce a visible embryonic phenotype in this species--and will clone the majority of the mutated alleles. So far, we have isolated more than 500 insertional mutants. Here we describe the first 75 insertional mutants for which the disrupted genes have been identified. In agreement with chemical mutagenesis screens, approximately one-third of the mutants have developmental defects that affect primarily one or a small number of organs, body shape or swimming behavior; the rest of the mutants show more widespread or pleiotropic abnormalities. Many of the genes we identified have not been previously assigned a biological role in vivo. Roughly 20% of the mutants result from lesions in genes for which the biochemical and cellular function of the proteins they encode cannot be deduced with confidence, if at all, from their predicted amino-acid sequences. All of the genes have either orthologs or clearly related genes in human. These results provide an unbiased view of the genetic construction kit for a vertebrate embryo, reveal the diversity of genes required for vertebrate development and suggest that hundreds of genes of unknown biochemical function essential for vertebrate development have yet to be identified. 相似文献
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Stöck M Lamatsch DK Steinlein C Epplen JT Grosse WR Hock R Klapperstück T Lampert KP Scheer U Schmid M Schartl M 《Nature genetics》2002,30(3):325-328
Green toads are common in the Palaearctic region, where they have differentiated into several taxa. The toads exist with variable amounts of ploidy, similar to other anuran species or reptiles. In vertebrate biology, the very rare occurrence of triploidy is coupled with infertility or unisexuality, or requires the coexistence of individuals of different ploidy in a reproductive community. The reproduction of naturally occurring triploids has been reported to occur only through parthenogenesis, gynogenesis or hybridogenesis. The bisexual reproduction of pure triploids has been considered to be impossible because of the problem of equally distributing three chromosome sets in meiosis. Here we report geographically isolated populations of green toads (Bufo viridis complex) that are all-triploid and reproduce bisexually. 相似文献
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Interaction of reelin signaling and Lis1 in brain development 总被引:1,自引:0,他引:1
Assadi AH Zhang G Beffert U McNeil RS Renfro AL Niu S Quattrocchi CC Antalffy BA Sheldon M Armstrong DD Wynshaw-Boris A Herz J D'Arcangelo G Clark GD 《Nature genetics》2003,35(3):270-276
Loss-of-function mutations in RELN (encoding reelin) or PAFAH1B1 (encoding LIS1) cause lissencephaly, a human neuronal migration disorder. In the mouse, homozygous mutations in Reln result in the reeler phenotype, characterized by ataxia and disrupted cortical layers. Pafah1b1(+/-) mice have hippocampal layering defects, whereas homozygous mutants are embryonic lethal. Reln encodes an extracellular protein that regulates layer formation by interacting with VLDLR and ApoER2 (Lrp8) receptors, thereby phosphorylating the Dab1 signaling molecule. Lis1 associates with microtubules and modulates neuronal migration. We investigated interactions between the reelin signaling pathway and Lis1 in brain development. Compound mutant mice with disruptions in the Reln pathway and heterozygous Pafah1b1 mutations had a higher incidence of hydrocephalus and enhanced cortical and hippocampal layering defects. Dab1 and Lis1 bound in a reelin-induced phosphorylation-dependent manner. These data indicate genetic and biochemical interaction between the reelin signaling pathway and Lis1. 相似文献
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