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排序方式: 共有198条查询结果,搜索用时 328 毫秒
161.
162.
A naturally occurring epigenetic mutation in a gene encoding an SBP-box transcription factor inhibits tomato fruit ripening 总被引:26,自引:0,他引:26
Manning K Tör M Poole M Hong Y Thompson AJ King GJ Giovannoni JJ Seymour GB 《Nature genetics》2006,38(8):948-952
A major component in the regulatory network controlling fruit ripening is likely to be the gene at the tomato Colorless non-ripening (Cnr) locus. The Cnr mutation results in colorless fruits with a substantial loss of cell-to-cell adhesion. The nature of the mutation and the identity of the Cnr gene were previously unknown. Using positional cloning and virus-induced gene silencing, here we demonstrate that an SBP-box (SQUAMOSA promoter binding protein-like) gene resides at the Cnr locus. Furthermore, the Cnr phenotype results from a spontaneous epigenetic change in the SBP-box promoter. The discovery that Cnr is an epimutation was unexpected, as very few spontaneous epimutations have been described in plants. This study demonstrates that an SBP-box gene is critical for normal ripening and highlights the likely importance of epialleles in plant development and the generation of natural variation. 相似文献
163.
Crow YJ Leitch A Hayward BE Garner A Parmar R Griffith E Ali M Semple C Aicardi J Babul-Hirji R Baumann C Baxter P Bertini E Chandler KE Chitayat D Cau D Déry C Fazzi E Goizet C King MD Klepper J Lacombe D Lanzi G Lyall H Martínez-Frías ML Mathieu M McKeown C Monier A Oade Y Quarrell OW Rittey CD Rogers RC Sanchis A Stephenson JB Tacke U Till M Tolmie JL Tomlin P Voit T Weschke B Woods CG Lebon P Bonthron DT Ponting CP Jackson AP 《Nature genetics》2006,38(8):910-916
Aicardi-Goutières syndrome (AGS) is an autosomal recessive neurological disorder, the clinical and immunological features of which parallel those of congenital viral infection. Here we define the composition of the human ribonuclease H2 enzyme complex and show that AGS can result from mutations in the genes encoding any one of its three subunits. Our findings demonstrate a role for ribonuclease H in human neurological disease and suggest an unanticipated relationship between ribonuclease H2 and the antiviral immune response that warrants further investigation. 相似文献
164.
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
165.
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
166.
Bruno Madio Steve Peigneur Yanni K. Y. Chin Brett R. Hamilton Sónia Troeira Henriques Jennifer J. Smith Ben Cristofori-Armstrong Zoltan Dekan Berin A. Boughton Paul F. Alewood Jan Tytgat Glenn F. King Eivind A. B. Undheim 《Cellular and molecular life sciences : CMLS》2018,75(24):4511-4524
Sea anemone venoms have long been recognized as a rich source of peptides with interesting pharmacological and structural properties, but they still contain many uncharacterized bioactive compounds. Here we report the discovery, three-dimensional structure, activity, tissue localization, and putative function of a novel sea anemone peptide toxin that constitutes a new, sixth type of voltage-gated potassium channel (KV) toxin from sea anemones. Comprised of just 17 residues, κ-actitoxin-Ate1a (Ate1a) is the shortest sea anemone toxin reported to date, and it adopts a novel three-dimensional structure that we have named the Proline-Hinged Asymmetric β-hairpin (PHAB) fold. Mass spectrometry imaging and bioassays suggest that Ate1a serves a primarily predatory function by immobilising prey, and we show this is achieved through inhibition of Shaker-type KV channels. Ate1a is encoded as a multi-domain precursor protein that yields multiple identical mature peptides, which likely evolved by multiple domain duplication events in an actinioidean ancestor. Despite this ancient evolutionary history, the PHAB-encoding gene family exhibits remarkable sequence conservation in the mature peptide domains. We demonstrate that this conservation is likely due to intra-gene concerted evolution, which has to our knowledge not previously been reported for toxin genes. We propose that the concerted evolution of toxin domains provides a hitherto unrecognised way to circumvent the effects of the costly evolutionary arms race considered to drive toxin gene evolution by ensuring efficient secretion of ecologically important predatory toxins. 相似文献
167.
Mutations in COL11A2 cause non-syndromic hearing loss (DFNA13) 总被引:13,自引:0,他引:13
McGuirt WT Prasad SD Griffith AJ Kunst HP Green GE Shpargel KB Runge C Huybrechts C Mueller RF Lynch E King MC Brunner HG Cremers CW Takanosu M Li SW Arita M Mayne R Prockop DJ Van Camp G Smith RJ 《Nature genetics》1999,23(4):413-419
We report that mutation of COL11A2 causes deafness previously mapped to the DFNA13 locus on chromosome 6p. We found two families (one American and one Dutch) with autosomal dominant, non-syndromic hearing loss to have mutations in COL11A2 that are predicted to affect the triple-helix domain of the collagen protein. In both families, deafness is non-progressive and predominantly affects middle frequencies. Mice with a targeted disruption of Col11a2 also were shown to have hearing loss. Electron microscopy of the tectorial membrane of these mice revealed loss of organization of the collagen fibrils. Our findings revealed a unique ultrastructural malformation of inner-ear architecture associated with non-syndromic hearing loss, and suggest that tectorial membrane abnormalities may be one aetiology of sensorineural hearing loss primarily affecting the mid-frequencies. 相似文献
168.
169.
Anne Stephens Chris Jacobson Christine King 《Systemic Practice and Action Research》2010,23(5):371-386
This paper provides the findings of a study to locate the similarity and/or differences between two epistemologies: critical
systems thinking and cultural ecofeminism. Selected texts from authors in each field were coded and compared using the Constant
comparative analysis, grounded theory method. The analysis revealed a multitude of similarities across a range of concepts,
including systems thinking language; challenges to positivist science, reason and instrumentalism; ethics and morality and
praxis. The analysis also revealed several emergent principles for working towards a feminist systems theory of practice. 相似文献
170.
Preweaning malnutrition permanently reduced brain size and cellular content but in spite of changes in the adrenocotical stress response no learning deficit was observed. Differential rearing environments did not influence the effects of malnutrition. 相似文献