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排序方式: 共有216条查询结果,搜索用时 62 毫秒
141.
Impaired T(H)17 cell differentiation in subjects with autosomal dominant hyper-IgE syndrome 总被引:1,自引:0,他引:1
Milner JD Brenchley JM Laurence A Freeman AF Hill BJ Elias KM Kanno Y Spalding C Elloumi HZ Paulson ML Davis J Hsu A Asher AI O'Shea J Holland SM Paul WE Douek DC 《Nature》2008,452(7188):773-776
142.
Cyclical DNA methylation of a transcriptionally active promoter 总被引:3,自引:0,他引:3
Métivier R Gallais R Tiffoche C Le Péron C Jurkowska RZ Carmouche RP Ibberson D Barath P Demay F Reid G Benes V Jeltsch A Gannon F Salbert G 《Nature》2008,452(7183):45-50
143.
Alternative isoform regulation in human tissue transcriptomes 总被引:13,自引:0,他引:13
Wang ET Sandberg R Luo S Khrebtukova I Zhang L Mayr C Kingsmore SF Schroth GP Burge CB 《Nature》2008,456(7221):470-476
144.
The potential usefulness of human embryonic stem cells for therapy derives from their ability to form any cell in the body. This potential has been used to justify intensive research despite some ethical concerns. In parallel, scientists have searched for adult stem cells that can be used as an alternative to embryonic cells, and, for the heart at least, these efforts have led to promising results. However, most adult cardiomyocytes are unable to divide and form new cardiomyocytes and would therefore be unable to replace those lost as a result of disease. Basic questions--for example, whether cardiomyocyte replacement or alternatives, such as providing the damaged heart with new blood vessels or growth factors to activate resident stem cells, are the best approach--remain to be fully addressed. Despite this, preclinical studies on cardiomyocyte transplantation in animals and the first clinical trials with adult stem cells have recently been published with mixed results. 相似文献
145.
Strigolactone inhibition of shoot branching 总被引:16,自引:0,他引:16
Gomez-Roldan V Fermas S Brewer PB Puech-Pagès V Dun EA Pillot JP Letisse F Matusova R Danoun S Portais JC Bouwmeester H Bécard G Beveridge CA Rameau C Rochange SF 《Nature》2008,455(7210):189-194
A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence that carotenoid cleavage dioxygenase 8 shoot branching mutants of pea are strigolactone deficient and that strigolactone application restores the wild-type branching phenotype to ccd8 mutants. Moreover, we show that other branching mutants previously characterized as lacking a response to the branching inhibition signal also lack strigolactone response, and are not deficient in strigolactones. These responses are conserved in Arabidopsis. In agreement with the expected properties of the hormonal signal, exogenous strigolactone can be transported in shoots and act at low concentrations. We suggest that endogenous strigolactones or related compounds inhibit shoot branching in plants. Furthermore, ccd8 mutants demonstrate the diverse effects of strigolactones in shoot branching, mycorrhizal symbiosis and parasitic weed interaction. 相似文献
146.
Verpy E Weil D Leibovici M Goodyear RJ Hamard G Houdon C Lefèvre GM Hardelin JP Richardson GP Avan P Petit C 《Nature》2008,456(7219):255-258
Although the cochlea is an amplifier and a remarkably sensitive and finely tuned detector of sounds, it also produces conspicuous mechanical and electrical waveform distortions. These distortions reflect nonlinear mechanical interactions within the cochlea. By allowing one tone to suppress another (masking effect), they contribute to speech intelligibility. Tones can also combine to produce sounds with frequencies not present in the acoustic stimulus. These sounds compose the otoacoustic emissions that are extensively used to screen hearing in newborns. Because both cochlear amplification and distortion originate from the outer hair cells-one of the two types of sensory receptor cells-it has been speculated that they stem from a common mechanism. Here we show that the nonlinearity underlying cochlear waveform distortions relies on the presence of stereocilin, a protein defective in a recessive form of human deafness. Stereocilin was detected in association with horizontal top connectors, lateral links that join adjacent stereocilia within the outer hair cell's hair bundle. These links were absent in stereocilin-null mutant mice, which became progressively deaf. At the onset of hearing, however, their cochlear sensitivity and frequency tuning were almost normal, although masking was much reduced and both acoustic and electrical waveform distortions were completely lacking. From this unique functional situation, we conclude that the main source of cochlear waveform distortions is a deflection-dependent hair bundle stiffness resulting from constraints imposed by the horizontal top connectors, and not from the intrinsic nonlinear behaviour of the mechanoelectrical transducer channel. 相似文献
147.
148.
Ellinor PT Lunetta KL Albert CM Glazer NL Ritchie MD Smith AV Arking DE Müller-Nurasyid M Krijthe BP Lubitz SA Bis JC Chung MK Dörr M Ozaki K Roberts JD Smith JG Pfeufer A Sinner MF Lohman K Ding J Smith NL Smith JD Rienstra M Rice KM Van Wagoner DR Magnani JW Wakili R Clauss S Rotter JI Steinbeck G Launer LJ Davies RW Borkovich M Harris TB Lin H Völker U Völzke H Milan DJ Hofman A Boerwinkle E Chen LY Soliman EZ Voight BF Li G Chakravarti A Kubo M Tedrow UB Rose LM Ridker PM Conen D Tsunoda T 《Nature genetics》2012,44(6):670-675
149.
Rivière JB Mirzaa GM O'Roak BJ Beddaoui M Alcantara D Conway RL St-Onge J Schwartzentruber JA Gripp KW Nikkel SM Worthylake T Sullivan CT Ward TR Butler HE Kramer NA Albrecht B Armour CM Armstrong L Caluseriu O Cytrynbaum C Drolet BA Innes AM Lauzon JL Lin AE Mancini GM Meschino WS Reggin JD Saggar AK Lerman-Sagie T Uyanik G Weksberg R Zirn B Beaulieu CL;Finding of Rare Disease Genes 《Nature genetics》2012,44(8):934-940
Megalencephaly-capillary malformation (MCAP) and megalencephaly-polymicrogyria-polydactyly-hydrocephalus (MPPH) syndromes are sporadic overgrowth disorders associated with markedly enlarged brain size and other recognizable features. We performed exome sequencing in 3 families with MCAP or MPPH, and our initial observations were confirmed in exomes from 7 individuals with MCAP and 174 control individuals, as well as in 40 additional subjects with megalencephaly, using a combination of Sanger sequencing, restriction enzyme assays and targeted deep sequencing. We identified de novo germline or postzygotic mutations in three core components of the phosphatidylinositol 3-kinase (PI3K)-AKT pathway. These include 2 mutations in AKT3, 1 recurrent mutation in PIK3R2 in 11 unrelated families with MPPH and 15 mostly postzygotic mutations in PIK3CA in 23 individuals with MCAP and 1 with MPPH. Our data highlight the central role of PI3K-AKT signaling in vascular, limb and brain development and emphasize the power of massively parallel sequencing in a challenging context of phenotypic and genetic heterogeneity combined with postzygotic mosaicism. 相似文献
150.
Haiman CA Chen GK Vachon CM Canzian F Dunning A Millikan RC Wang X Ademuyiwa F Ahmed S Ambrosone CB Baglietto L Balleine R Bandera EV Beckmann MW Berg CD Bernstein L Blomqvist C Blot WJ Brauch H Buring JE Carey LA Carpenter JE Chang-Claude J Chanock SJ Chasman DI Clarke CL Cox A Cross SS Deming SL Diasio RB Dimopoulos AM Driver WR Dünnebier T Durcan L Eccles D Edlund CK Ekici AB Fasching PA Feigelson HS Flesch-Janys D Fostira F Försti A Fountzilas G 《Nature genetics》2011,43(12):1210-1214
Estrogen receptor (ER)-negative breast cancer shows a higher incidence in women of African ancestry compared to women of European ancestry. In search of common risk alleles for ER-negative breast cancer, we combined genome-wide association study (GWAS) data from women of African ancestry (1,004 ER-negative cases and 2,745 controls) and European ancestry (1,718 ER-negative cases and 3,670 controls), with replication testing conducted in an additional 2,292 ER-negative cases and 16,901 controls of European ancestry. We identified a common risk variant for ER-negative breast cancer at the TERT-CLPTM1L locus on chromosome 5p15 (rs10069690: per-allele odds ratio (OR) = 1.18 per allele, P = 1.0 × 10(-10)). The variant was also significantly associated with triple-negative (ER-negative, progesterone receptor (PR)-negative and human epidermal growth factor-2 (HER2)-negative) breast cancer (OR = 1.25, P = 1.1 × 10(-9)), particularly in younger women (<50 years of age) (OR = 1.48, P = 1.9 × 10(-9)). Our results identify a genetic locus associated with estrogen receptor negative breast cancer subtypes in multiple populations. 相似文献