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71.
A problem situation that is at the heart of a New Zealand higher education institute applying for university status is meeting the requirement for sufficient academic staff with postgraduate qualifications. For this particular New Zealand higher education institute that was originally a teaching institution offering only sub-degree qualifications, the move to firstly offering degrees and secondly seeking university status has meant that employment conditions have shifted for many academics. In order to explore the multiple world views on the impact to the whole system of a significant number of staff upgrading qualifications whilst engaged in full-time teaching at the same time, views were sought from senior executives, heads of schools, human resource personnel and staff engaged in their own postgraduate study. Multiple conceptual models have been utilised to gain an understanding of this problem situation: Soft Systems Methodology (Checkland and Scholes, 1990, 1999) in both its original and its current form; complexity theory (McKenna, 1999; Merry, 1995; Stacey, 1996) and context-dependent cluster model (CDCM) (Fielden and London, 2001). These multiple conceptual models have all contributed to providing a basis upon which to compare multiple-perceived worlds with appropriate conceptual models upon which to base a future action plan.Outcomes discussed are both positive and negative factors including: recognition, time, stress, employment contracts, senior staff expectations, family, collegial and institutional support and the integration of own study with teaching practice and content. Implications for alignment across institutional organisational levels and also for higher education outside of the university sector are also discussed. 相似文献
72.
Regulation of phyllotaxis by polar auxin transport 总被引:5,自引:0,他引:5
Reinhardt D Pesce ER Stieger P Mandel T Baltensperger K Bennett M Traas J Friml J Kuhlemeier C 《Nature》2003,426(6964):255-260
The regular arrangement of leaves around a plant's stem, called phyllotaxis, has for centuries attracted the attention of philosophers, mathematicians and natural scientists; however, to date, studies of phyllotaxis have been largely theoretical. Leaves and flowers are formed from the shoot apical meristem, triggered by the plant hormone auxin. Auxin is transported through plant tissues by specific cellular influx and efflux carrier proteins. Here we show that proteins involved in auxin transport regulate phyllotaxis. Our data indicate that auxin is transported upwards into the meristem through the epidermis and the outermost meristem cell layer. Existing leaf primordia act as sinks, redistributing auxin and creating its heterogeneous distribution in the meristem. Auxin accumulation occurs only at certain minimal distances from existing primordia, defining the position of future primordia. This model for phyllotaxis accounts for its reiterative nature, as well as its regularity and stability. 相似文献
73.
Supernova explosions in the Universe 总被引:1,自引:0,他引:1
During the lifetime of our Milky Way galaxy, there have been something like 100 million supernova explosions, which have enriched the Galaxy with the oxygen we breathe, the iron in our cars, the calcium in our bones and the silicon in the rocks beneath our feet. These exploding stars also influence the birth of new stars and are the source of the energetic cosmic rays that irradiate us on the Earth. The prodigious amount of energy (approximately 10(51), or approximately 2.5 x 10(28) megatonnes of TNT equivalent) and momentum associated with each supernova may even have helped to shape galaxies as they formed in the early Universe. Supernovae are now being used to measure the geometry of the Universe, and have recently been implicated in the decades-old mystery of the origin of the gamma-ray bursts. Together with major conceptual advances in our theoretical understanding of supernovae, these developments have made supernovae the centre of attention in astrophysics. 相似文献
74.
Soderberg AM Berger E Page KL Schady P Parrent J Pooley D Wang XY Ofek EO Cucchiara A Rau A Waxman E Simon JD Bock DC Milne PA Page MJ Barentine JC Barthelmy SD Beardmore AP Bietenholz MF Brown P Burrows A Burrows DN Bryngelson G Byrngelson G Cenko SB Chandra P Cummings JR Fox DB Gal-Yam A Gehrels N Immler S Kasliwal M Kong AK Krimm HA Kulkarni SR Maccarone TJ Mészáros P Nakar E O'Brien PT Overzier RA de Pasquale M Racusin J Rea N York DG 《Nature》2008,453(7194):469-474
Massive stars end their short lives in spectacular explosions--supernovae--that synthesize new elements and drive galaxy evolution. Historically, supernovae were discovered mainly through their 'delayed' optical light (some days after the burst of neutrinos that marks the actual event), preventing observations in the first moments following the explosion. As a result, the progenitors of some supernovae and the events leading up to their violent demise remain intensely debated. Here we report the serendipitous discovery of a supernova at the time of the explosion, marked by an extremely luminous X-ray outburst. We attribute the outburst to the 'break-out' of the supernova shock wave from the progenitor star, and show that the inferred rate of such events agrees with that of all core-collapse supernovae. We predict that future wide-field X-ray surveys will catch each year hundreds of supernovae in the act of exploding. 相似文献
75.
Listed are 96 species of Scolytidae (Coleoptera) from Montana. Eighteen species reported from Montana for the first time are: Scierus pubescens Swaine, Hylastinus obscurus (Marsham), Hylesinus aculeatus Say, Hylesinus californicus (Swaine), Hylesinus criddlei (Swaine), Pseudohylesinus granulatus (LeConte), Dendroctunus punctatus LeConte, Phloeosinus hoferi Blackman, Phloeosinus pini Swaine, Carphoborus pinicolens Wood, Scolytus subscaber LeConte, Ips grandicollis (Eichhoff), Trypodendron betulae Swaine, Trypodendron retusum (LeConte), Trypophloeus populi Hopkins, Procryphalus mucronatus, (LeConte), Pityophthorus alpinensis G. Hopping, and Gnathotrichus denticulatus Blackman. 相似文献
76.
Evans DM Spencer CC Pointon JJ Su Z Harvey D Kochan G Oppermann U Opperman U Dilthey A Pirinen M Stone MA Appleton L Moutsianas L Moutsianis L Leslie S Wordsworth T Kenna TJ Karaderi T Thomas GP Ward MM Weisman MH Farrar C Bradbury LA Danoy P Inman RD Maksymowych W Gladman D Rahman P;Spondyloarthritis Research Consortium of Canada 《Nature genetics》2011,43(8):761-767
Ankylosing spondylitis is a common form of inflammatory arthritis predominantly affecting the spine and pelvis that occurs in approximately 5 out of 1,000 adults of European descent. Here we report the identification of three variants in the RUNX3, LTBR-TNFRSF1A and IL12B regions convincingly associated with ankylosing spondylitis (P < 5 × 10(-8) in the combined discovery and replication datasets) and a further four loci at PTGER4, TBKBP1, ANTXR2 and CARD9 that show strong association across all our datasets (P < 5 × 10(-6) overall, with support in each of the three datasets studied). We also show that polymorphisms of ERAP1, which encodes an endoplasmic reticulum aminopeptidase involved in peptide trimming before HLA class I presentation, only affect ankylosing spondylitis risk in HLA-B27-positive individuals. These findings provide strong evidence that HLA-B27 operates in ankylosing spondylitis through a mechanism involving aberrant processing of antigenic peptides. 相似文献
77.
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
78.
Haiman CA Patterson N Freedman ML Myers SR Pike MC Waliszewska A Neubauer J Tandon A Schirmer C McDonald GJ Greenway SC Stram DO Le Marchand L Kolonel LN Frasco M Wong D Pooler LC Ardlie K Oakley-Girvan I Whittemore AS Cooney KA John EM Ingles SA Altshuler D Henderson BE Reich D 《Nature genetics》2007,39(5):638-644
After the recent discovery that common genetic variation in 8q24 influences inherited risk of prostate cancer, we genotyped 2,973 SNPs in up to 7,518 men with and without prostate cancer from five populations. We identified seven risk variants, five of them previously undescribed, spanning 430 kb and each independently predicting risk for prostate cancer (P = 7.9 x 10(-19) for the strongest association, and P < 1.5 x 10(-4) for five of the variants, after controlling for each of the others). The variants define common genotypes that span a more than fivefold range of susceptibility to cancer in some populations. None of the prostate cancer risk variants aligns to a known gene or alters the coding sequence of an encoded protein. 相似文献
79.
80.
INTERMEDIUM-C, a modifier of lateral spikelet fertility in barley, is an ortholog of the maize domestication gene TEOSINTE BRANCHED 1 总被引:1,自引:0,他引:1
Ramsay L Comadran J Druka A Marshall DF Thomas WT Macaulay M MacKenzie K Simpson C Fuller J Bonar N Hayes PM Lundqvist U Franckowiak JD Close TJ Muehlbauer GJ Waugh R 《Nature genetics》2011,43(2):169-172
The domestication of cereals has involved common changes in morphological features, such as seed size, seed retention and modification of vegetative and inflorescence architecture that ultimately contributed to an increase in harvested yield. In barley, this process has resulted in two different cultivated types, two-rowed and six-rowed forms, both derived from the wild two-rowed ancestor, with archaeo-botanical evidence indicating the origin of six-rowed barley early in the domestication of the species, some 8,600-8,000 years ago. Variation at SIX-ROWED SPIKE 1 (VRS1) is sufficient to control this phenotype. However, phenotypes imposed by VRS1 alleles are modified by alleles at the INTERMEDIUM-C (INT-C) locus. Here we show that INT-C is an ortholog of the maize domestication gene TEOSINTE BRANCHED 1 (TB1) and identify 17 coding mutations in barley TB1 correlated with lateral spikelet fertility phenotypes. 相似文献