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排序方式: 共有108条查询结果,搜索用时 15 毫秒
41.
Regulation of progenitor cell proliferation and granulocyte function by microRNA-223 总被引:1,自引:0,他引:1
Johnnidis JB Harris MH Wheeler RT Stehling-Sun S Lam MH Kirak O Brummelkamp TR Fleming MD Camargo FD 《Nature》2008,451(7182):1125-1129
42.
Grbić M Van Leeuwen T Clark RM Rombauts S Rouzé P Grbić V Osborne EJ Dermauw W Ngoc PC Ortego F Hernández-Crespo P Diaz I Martinez M Navajas M Sucena É Magalhães S Nagy L Pace RM Djuranović S Smagghe G Iga M Christiaens O Veenstra JA Ewer J Villalobos RM Hutter JL Hudson SD Velez M Yi SV Zeng J Pires-daSilva A Roch F Cazaux M Navarro M Zhurov V Acevedo G Bjelica A Fawcett JA Bonnet E Martens C Baele G Wissler L Sanchez-Rodriguez A Tirry L Blais C Demeestere K Henz SR Gregory TR Mathieu J 《Nature》2011,479(7374):487-492
43.
44.
Santiago Montoya-Molina Fernando Z. Vaz-De-Mello 《Journal of Natural History》2019,53(45-46):2763-2769
ABSTRACTWe found that Pinotus foveicollis synonym of D. agenor, does not belong to this group of species, neither is synonym of D. agenor. Here the species is revalidated to Dichotomius (Luederwaldtinia) foveicollis, the female is re-described, and the male is described for the first time. Based on male diagnostic characters the species is moved from D. agenor to D. inachus species-group. 相似文献
45.
Hundreds of variants clustered in genomic loci and biological pathways affect human height 总被引:2,自引:0,他引:2
Lango Allen H Estrada K Lettre G Berndt SI Weedon MN Rivadeneira F Willer CJ Jackson AU Vedantam S Raychaudhuri S Ferreira T Wood AR Weyant RJ Segrè AV Speliotes EK Wheeler E Soranzo N Park JH Yang J Gudbjartsson D Heard-Costa NL Randall JC Qi L Vernon Smith A Mägi R Pastinen T Liang L Heid IM Luan J Thorleifsson G Winkler TW Goddard ME Sin Lo K Palmer C Workalemahu T Aulchenko YS Johansson A Zillikens MC Feitosa MF Esko T Johnson T Ketkar S Kraft P Mangino M Prokopenko I Absher D Albrecht E 《Nature》2010,467(7317):832-838
Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P?0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways. 相似文献
46.
Mantle wedge control on back-arc crustal accretion 总被引:1,自引:0,他引:1
At mid-ocean ridges, plate separation leads to upward advection and pressure-release partial melting of fertile mantle material; the melt is then extracted to the spreading centre and the residual depleted mantle flows horizontally away. In back-arc basins, the subducting slab is an important control on the pattern of mantle advection and melt extraction, as well as on compositional and fluid gradients. Modelling studies predict significant mantle wedge effects on back-arc spreading processes. Here we show that various spreading centres in the Lau back-arc basin exhibit enhanced, diminished or normal magma supply, which correlates with distance from the arc volcanic front but not with spreading rate. To explain this correlation we propose that depleted upper-mantle material, generated by melt extraction in the mantle wedge, is overturned and re-introduced beneath the back-arc basin by subduction-induced corner flow. The spreading centres experience enhanced melt delivery near the volcanic front, diminished melting within the overturned depleted mantle farther from the corner and normal melting conditions in undepleted mantle farther away. Our model explains fundamental differences in crustal accretion variables between back-arc and mid-ocean settings. 相似文献
47.
Given a set of objects and a symmetric matrix of dissimilarities between them,
Unidimensional Scaling is the problem of finding a representation by locating points on a
continuum. Approximating dissimilarities by the absolute value of the difference between
coordinates on a line constitutes a serious computational problem. This paper presents an
algorithm that implements Simulated Annealing in a new way, via a strategy based on a
weighted alternating process that uses permutations and point-wise translations to locate
the optimal configuration. Explicit implementation details are given for least squares loss
functions and for least absolute deviations. The weighted, alternating process is shown
to outperform earlier implementations of Simulated Annealing and other optimization
strategies for Unidimensional Scaling in run time efficiency, in solution quality, or in
both. 相似文献
48.
Kobasa D Jones SM Shinya K Kash JC Copps J Ebihara H Hatta Y Kim JH Halfmann P Hatta M Feldmann F Alimonti JB Fernando L Li Y Katze MG Feldmann H Kawaoka Y 《Nature》2007,445(7125):319-323
The 1918 influenza pandemic was unusually severe, resulting in about 50 million deaths worldwide. The 1918 virus is also highly pathogenic in mice, and studies have identified a multigenic origin of this virulent phenotype in mice. However, these initial characterizations of the 1918 virus did not address the question of its pathogenic potential in primates. Here we demonstrate that the 1918 virus caused a highly pathogenic respiratory infection in a cynomolgus macaque model that culminated in acute respiratory distress and a fatal outcome. Furthermore, infected animals mounted an immune response, characterized by dysregulation of the antiviral response, that was insufficient for protection, indicating that atypical host innate immune responses may contribute to lethality. The ability of influenza viruses to modulate host immune responses, such as that demonstrated for the avian H5N1 influenza viruses, may be a feature shared by the virulent influenza viruses. 相似文献
49.
50.
Andrey V. Frolov Federico C. Ocampo Lilia A. Akhmetova Fernando Vaz-de-Mello 《Journal of Natural History》2017,51(29-30):1759-1765
The new hybosorine genus Taisia Frolov, Ocampo, Akhmetova et Vaz-de-Mello, gen. nov. is described from T. cornitermitis Frolov, Ocampo, Akhmetova et Vaz-de-Mello, sp. nov. from Mato Grosso State, Brazil. Taisia gen. nov. can be easily distinguished from the rest of the Neotropical Hybosorinae genera by the following characters: mandibular teeth long and robust; pronotum with serrate lateral margins; scutellum with two deep rectangular fossae basally; and metatibial apex protruding. Males of T. cornitermitis sp. nov. differ in having feather-like setae on the three basal tarsomeres of meso- and protarsi. The new taxon is associated with termites Cornitermes cf. bequaerti Emerson, 1952.
www.zoobank.org/urn:lsid:zoobank.org:pub:439DDABB-EBC2-4870-AA05-76ADC3BDB7D9 相似文献