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61.
Plasmaspheric hiss is a type of electromagnetic wave found ubiquitously in the dense plasma region that encircles the Earth, known as the plasmasphere. This important wave is known to remove the high-energy electrons that are trapped along the Earth's magnetic field lines, and therefore helps to reduce the radiation hazards to satellites and humans in space. Numerous theories to explain the origin of hiss have been proposed over the past four decades, but none have been able to account fully for its observed properties. Here we show that a different wave type called chorus, previously thought to be unrelated to hiss, can propagate into the plasmasphere from tens of thousands of kilometres away, and evolve into hiss. Our new model naturally accounts for the observed frequency band of hiss, its incoherent nature, its day-night asymmetry in intensity, its association with solar activity and its spatial distribution. The connection between chorus and hiss is very interesting because chorus is instrumental in the formation of high-energy electrons outside the plasmasphere, whereas hiss depletes these electrons at lower equatorial altitudes. 相似文献
62.
Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project 总被引:2,自引:0,他引:2
ENCODE Project Consortium Birney E Stamatoyannopoulos JA Dutta A Guigó R Gingeras TR Margulies EH Weng Z Snyder M Dermitzakis ET Thurman RE Kuehn MS Taylor CM Neph S Koch CM Asthana S Malhotra A Adzhubei I Greenbaum JA Andrews RM Flicek P Boyle PJ Cao H Carter NP Clelland GK Davis S Day N Dhami P Dillon SC Dorschner MO Fiegler H Giresi PG Goldy J Hawrylycz M Haydock A Humbert R James KD Johnson BE Johnson EM Frum TT Rosenzweig ER Karnani N Lee K Lefebvre GC Navas PA Neri F Parker SC Sabo PJ 《Nature》2007,447(7146):799-816
63.
It is well documented that the generations born around 1930 are consistently exhibiting higher rates of mortality improvement than the generations either side of them. There is currently no evidence that these differentials are declining. In current ONS National Population Projections, it is assumed that these cohorts will continue to experience higher rates of improvement. However, it is not yet precisely clear why this is so. This article details preliminary research carried out using the ONS Longitudinal Study to try to understand better why the members of the generation born around 1930 have been enjoying higher rates of mortality improvement throughout their adult life. 相似文献
64.
Nigel Aston 《Studies in history and philosophy of science》2004,35(3):625-644
This paper represents a provisional attempt to chart the intellectual construction of Hutchinsonianism over approximately a quarter of a century from the mid-1720s through to the early 1750s. It looks at how Hutchinson’s works were received and fashioned by his first followers, the means they used to communicate their conviction to others, and the extent to which their outlook can be characterised as anti-Newtonian. The paper argues for a slow take up of ‘Hutchinsonian’ views before Spearman and Bate published a collected edition of the master’s works in 1748. This single edition gave Hutchinson’s writings a coherence and a unity they were ill-designed to carry, but it created Hutchinsonianism as an appreciable force in Oxford and elsewhere. The paper concludes that the anti-Newtonian rhetoric of the movement’s founder was increasingly muted in the hands of his followers (with the exception of Bate), and by the 1750s the main bone of contention was less attitudes to Newton than approaches to Hebrew scholarship. 相似文献
65.
O'Donovan MC Craddock N Norton N Williams H Peirce T Moskvina V Nikolov I Hamshere M Carroll L Georgieva L Dwyer S Holmans P Marchini JL Spencer CC Howie B Leung HT Hartmann AM Möller HJ Morris DW Shi Y Feng G Hoffmann P Propping P Vasilescu C Maier W Rietschel M Zammit S Schumacher J Quinn EM Schulze TG Williams NM Giegling I Iwata N Ikeda M Darvasi A Shifman S He L Duan J Sanders AR Levinson DF Gejman PV Cichon S Nöthen MM Gill M Corvin A Rujescu D Kirov G Owen MJ Buccola NG Mowry BJ 《Nature genetics》2008,40(9):1053-1055
We carried out a genome-wide association study of schizophrenia (479 cases, 2,937 controls) and tested loci with P < 10(-5) in up to 16,726 additional subjects. Of 12 loci followed up, 3 had strong independent support (P < 5 x 10(-4)), and the overall pattern of replication was unlikely to occur by chance (P = 9 x 10(-8)). Meta-analysis provided strongest evidence for association around ZNF804A (P = 1.61 x 10(-7)) and this strengthened when the affected phenotype included bipolar disorder (P = 9.96 x 10(-9)). 相似文献
66.
Briggs TA Rice GI Daly S Urquhart J Gornall H Bader-Meunier B Baskar K Baskar S Baudouin V Beresford MW Black GC Dearman RJ de Zegher F Foster ES Francès C Hayman AR Hilton E Job-Deslandre C Kulkarni ML Le Merrer M Linglart A Lovell SC Maurer K Musset L Navarro V Picard C Puel A Rieux-Laucat F Roifman CM Scholl-Bürgi S Smith N Szynkiewicz M Wiedeman A Wouters C Zeef LA Casanova JL Elkon KB Janckila A Lebon P Crow YJ 《Nature genetics》2011,43(2):127-131
We studied ten individuals from eight families showing features consistent with the immuno-osseous dysplasia spondyloenchondrodysplasia. Of particular note was the diverse spectrum of autoimmune phenotypes observed in these individuals (cases), including systemic lupus erythematosus, Sj?gren's syndrome, hemolytic anemia, thrombocytopenia, hypothyroidism, inflammatory myositis, Raynaud's disease and vitiligo. Haplotype data indicated the disease gene to be on chromosome 19p13, and linkage analysis yielded a combined multipoint log(10) odds (LOD) score of 3.6. Sequencing of ACP5, encoding tartrate-resistant acid phosphatase, identified biallelic mutations in each of the cases studied, and in vivo testing confirmed a loss of expressed protein. All eight cases assayed showed elevated serum interferon alpha activity, and gene expression profiling in whole blood defined a type I interferon signature. Our findings reveal a previously unrecognized link between tartrate-resistant acid phosphatase activity and interferon metabolism and highlight the importance of type I interferon in the genesis of autoimmunity. 相似文献
67.
Goudie DR D'Alessandro M Merriman B Lee H Szeverényi I Avery S O'Connor BD Nelson SF Coats SE Stewart A Christie L Pichert G Friedel J Hayes I Burrows N Whittaker S Gerdes AM Broesby-Olsen S Ferguson-Smith MA Verma C Lunny DP Reversade B Lane EB 《Nature genetics》2011,43(4):365-369
Multiple self-healing squamous epithelioma (MSSE), also known as Ferguson-Smith disease (FSD), is an autosomal-dominant skin cancer condition characterized by multiple squamous-carcinoma-like locally invasive skin tumors that grow rapidly for a few weeks before spontaneously regressing, leaving scars. High-throughput genomic sequencing of a conservative estimate (24.2 Mb) of the disease locus on chromosome 9 using exon array capture identified independent mutations in TGFBR1 in three unrelated families. Subsequent dideoxy sequencing of TGFBR1 identified 11 distinct monoallelic mutations in 18 affected families, firmly establishing TGFBR1 as the causative gene. The nature of the sequence variants, which include mutations in the extracellular ligand-binding domain and a series of truncating mutations in the kinase domain, indicates a clear genotype-phenotype correlation between loss-of-function TGFBR1 mutations and MSSE. This distinguishes MSSE from the Marfan syndrome-related disorders in which missense mutations in TGFBR1 lead to developmental defects with vascular involvement but no reported predisposition to cancer. 相似文献
68.
Nollaig M. Bourke Silvia Napoletano Ciaran Bannan Suaad Ahmed Colm Bergin Áine McKnight Nigel J. Stevenson 《Cellular and molecular life sciences : CMLS》2018,75(5):775-783
Viral infections, including HIV, trigger the production of type I interferons (IFNs), which in turn, activate a signalling cascade that ultimately culminates with the expression of anti-viral proteins. Mounting evidence suggests that type I IFNs, in particular IFN-α, play a pivotal role in limiting acute HIV infection. Highly active anti-retroviral treatment reduces viral load and increases life expectancy in HIV positive patients; however, it fails to fully eliminate latent HIV reservoirs. To revisit HIV as a curable disease, this article reviews a body of literature that highlights type I IFNs as mediators in the control of HIV infection, with particular focus on the anti-HIV restriction factors induced and/or activated by IFN-α. In addition, we discuss the relevance of type I IFN treatment in the context of HIV latency reversal, novel therapeutic intervention strategies and the potential for full HIV clearance. 相似文献
69.
IntroductionChlorinated phenolic compounds,which aregenerated from a number of industrialmanufacturing processes,comprise the bulk of theenvironmental pollutants.Aqueous effluents fromindustrial operations such as polymeric resinproduction,oil refining,iron- steel,petroleum,pesticide,paint,solvent,pharmaceutics,woodpreserving chemicals,coke- oven,and paper andpulp industries contain chlorophenolic compounds.Their fate in the environment is of greatimportance as they are toxic,recalcitrant andb… 相似文献
70.
Turner DJ Miretti M Rajan D Fiegler H Carter NP Blayney ML Beck S Hurles ME 《Nature genetics》2008,40(1):90-95
Meiotic recombination between highly similar duplicated sequences (nonallelic homologous recombination, NAHR) generates deletions, duplications, inversions and translocations, and it is responsible for genetic diseases known as 'genomic disorders', most of which are caused by altered copy number of dosage-sensitive genes. NAHR hot spots have been identified within some duplicated sequences. We have developed sperm-based assays to measure the de novo rate of reciprocal deletions and duplications at four NAHR hot spots. We used these assays to dissect the relative rates of NAHR between different pairs of duplicated sequences. We show that (i) these NAHR hot spots are specific to meiosis, (ii) deletions are generated at a higher rate than their reciprocal duplications in the male germline and (iii) some of these genomic disorders are likely to have been underascertained clinically, most notably that resulting from the duplication of 7q11, the reciprocal of the deletion causing Williams-Beuren syndrome. 相似文献