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排序方式: 共有410条查询结果,搜索用时 15 毫秒
241.
Hatlestad GJ Sunnadeniya RM Akhavan NA Gonzalez A Goldman IL McGrath JM Lloyd AM 《Nature genetics》2012,44(7):816-820
Anthocyanins are red and violet pigments that color flowers, fruits and epidermal tissues in virtually all flowering plants. A single order, Caryophyllales, contains families in which an unrelated family of pigments, the betalains, color tissues normally pigmented by anthocyanins. Here we show that CYP76AD1 encoding a novel cytochrome P450 is required to produce the red betacyanin pigments in beets. Gene silencing of CYP76AD1 results in loss of red pigment and production of only yellow betaxanthin pigment. Yellow betalain mutants are complemented by transgenic expression of CYP76AD1, and an insertion in CYP76AD1 maps to the R locus that is responsible for yellow versus red pigmentation. Finally, expression of CYP76AD1 in yeast verifies its position in the betalain biosynthetic pathway. Thus, this cytochrome P450 performs the biosynthetic step that provides the cyclo-DOPA moiety of all red betacyanins. This discovery will contribute to our ability to engineer this simple, nutritionally valuable pathway into heterologous species. 相似文献
242.
TGFB2 mutations cause familial thoracic aortic aneurysms and dissections associated with mild systemic features of Marfan syndrome 总被引:1,自引:0,他引:1
C Boileau DC Guo N Hanna ES Regalado D Detaint L Gong M Varret SK Prakash AH Li H d'Indy AC Braverman B Grandchamp CS Kwartler L Gouya RL Santos-Cortez M Abifadel SM Leal C Muti J Shendure MS Gross MJ Rieder A Vahanian DA Nickerson JB Michel;National Heart Lung Blood Institute 《Nature genetics》2012,44(8):916-921
A predisposition for thoracic aortic aneurysms leading to acute aortic dissections can be inherited in families in an autosomal dominant manner. Genome-wide linkage analysis of two large unrelated families with thoracic aortic disease followed by whole-exome sequencing of affected relatives identified causative mutations in TGFB2. These mutations-a frameshift mutation in exon 6 and a nonsense mutation in exon 4-segregated with disease with a combined logarithm of odds (LOD) score of 7.7. Sanger sequencing of 276 probands from families with inherited thoracic aortic disease identified 2 additional TGFB2 mutations. TGFB2 encodes transforming growth factor (TGF)-β2, and the mutations are predicted to cause haploinsufficiency for TGFB2; however, aortic tissue from cases paradoxically shows increased TGF-β2 expression and immunostaining. Thus, haploinsufficiency for TGFB2 predisposes to thoracic aortic disease, suggesting that the initial pathway driving disease is decreased cellular TGF-β2 levels leading to a secondary increase in TGF-β2 production in the diseased aorta. 相似文献
243.
KU Ludwig E Mangold S Herms S Nowak H Reutter A Paul J Becker R Herberz T Alchawa E Nasser AC Böhmer M Mattheisen MA Alblas S Barth N Kluck C Lauster B Braumann RH Reich A Hemprich S Pötzsch B Blaumeiser N Daratsianos T Kreusch JC Murray ML Marazita I Ruczinski AF Scott TH Beaty FJ Kramer TF Wienker RP Steegers-Theunissen M Rubini PA Mossey P Hoffmann C Lange S Cichon P Propping M Knapp MM Nöthen 《Nature genetics》2012,44(9):968-971
We have conducted the first meta-analyses for nonsyndromic cleft lip with or without cleft palate (NSCL/P) using data from the two largest genome-wide association studies published to date. We confirmed associations with all previously identified loci and identified six additional susceptibility regions (1p36, 2p21, 3p11.1, 8q21.3, 13q31.1 and 15q22). Analysis of phenotypic variability identified the first specific genetic risk factor for NSCLP (nonsyndromic cleft lip plus palate) (rs8001641; P(NSCLP) = 6.51 × 10(-11); homozygote relative risk = 2.41, 95% confidence interval (CI) 1.84-3.16). 相似文献
244.
Jaeger E Webb E Howarth K Carvajal-Carmona L Rowan A Broderick P Walther A Spain S Pittman A Kemp Z Sullivan K Heinimann K Lubbe S Domingo E Barclay E Martin L Gorman M Chandler I Vijayakrishnan J Wood W Papaemmanuil E Penegar S Qureshi M;CORGI Consortium Farrington S Tenesa A Cazier JB Kerr D Gray R Peto J Dunlop M Campbell H Thomas H Houlston R Tomlinson I 《Nature genetics》2008,40(1):26-28
We mapped a high-penetrance gene (CRAC1; also known as HMPS) associated with colorectal cancer (CRC) in the Ashkenazi population to a 0.6-Mb region on chromosome 15 containing SCG5 (also known as SGNE1), GREM1 and FMN1. We hypothesized that the CRAC1 locus harbored low-penetrance variants that increased CRC risk in the general population. In a large series of colorectal cancer cases and controls, SNPs near GREM1 and SCG5 were strongly associated with increased CRC risk (for rs4779584, P = 4.44 x 10(-14)). 相似文献
245.
Sequence variants in the autophagy gene IRGM and multiple other replicating loci contribute to Crohn's disease susceptibility 总被引:14,自引:0,他引:14
Parkes M Barrett JC Prescott NJ Tremelling M Anderson CA Fisher SA Roberts RG Nimmo ER Cummings FR Soars D Drummond H Lees CW Khawaja SA Bagnall R Burke DA Todhunter CE Ahmad T Onnie CM McArdle W Strachan D Bethel G Bryan C Lewis CM Deloukas P Forbes A Sanderson J Jewell DP Satsangi J Mansfield JC;Wellcome Trust Case Control Consortium Cardon L Mathew CG 《Nature genetics》2007,39(7):830-832
A genome-wide association scan in individuals with Crohn's disease by the Wellcome Trust Case Control Consortium detected strong association at four novel loci. We tested 37 SNPs from these and other loci for association in an independent case-control sample. We obtained replication for the autophagy-inducing IRGM gene on chromosome 5q33.1 (replication P = 6.6 x 10(-4), combined P = 2.1 x 10(-10)) and for nine other loci, including NKX2-3, PTPN2 and gene deserts on chromosomes 1q and 5p13. 相似文献
246.
New models of collaboration in genome-wide association studies: the Genetic Association Information Network 总被引:7,自引:0,他引:7
GAIN Collaborative Research Group Manolio TA Rodriguez LL Brooks L Abecasis G;Collaborative Association Study of Psoriasis Ballinger D Daly M Donnelly P Faraone SV;International Multi-Center ADHD Genetics Project Frazer K Gabriel S Gejman P;Molecular Genetics of Schizophrenia Collaboration Guttmacher A Harris EL Insel T Kelsoe JR;Bipolar Genome Study Lander E McCowin N Mailman MD Nabel E Ostell J Pugh E Sherry S 《Nature genetics》2007,39(9):1045-1051
The Genetic Association Information Network (GAIN) is a public-private partnership established to investigate the genetic basis of common diseases through a series of collaborative genome-wide association studies. GAIN has used new approaches for project selection, data deposition and distribution, collaborative analysis, publication and protection from premature intellectual property claims. These demonstrate a new commitment to shared scientific knowledge that should facilitate rapid advances in understanding the genetics of complex diseases. 相似文献
247.
Sotoodehnia N Isaacs A de Bakker PI Dörr M Newton-Cheh C Nolte IM van der Harst P Müller M Eijgelsheim M Alonso A Hicks AA Padmanabhan S Hayward C Smith AV Polasek O Giovannone S Fu J Magnani JW Marciante KD Pfeufer A Gharib SA Teumer A Li M Bis JC Rivadeneira F Aspelund T Köttgen A Johnson T Rice K Sie MP Wang YA Klopp N Fuchsberger C Wild SH Mateo Leach I Estrada K Völker U Wright AF Asselbergs FW Qu J Chakravarti A Sinner MF Kors JA Petersmann A Harris TB Soliman EZ Munroe PB Psaty BM 《Nature genetics》2010,42(12):1068-1076
248.
249.
Pounds JA Bustamante MR Coloma LA Consuegra JA Fogden MP Foster PN La Marca E Masters KL Merino-Viteri A Puschendorf R Ron SR Sánchez-Azofeifa GA Still CJ Young BE 《Nature》2006,439(7073):161-167
As the Earth warms, many species are likely to disappear, often because of changing disease dynamics. Here we show that a recent mass extinction associated with pathogen outbreaks is tied to global warming. Seventeen years ago, in the mountains of Costa Rica, the Monteverde harlequin frog (Atelopus sp.) vanished along with the golden toad (Bufo periglenes). An estimated 67% of the 110 or so species of Atelopus, which are endemic to the American tropics, have met the same fate, and a pathogenic chytrid fungus (Batrachochytrium dendrobatidis) is implicated. Analysing the timing of losses in relation to changes in sea surface and air temperatures, we conclude with 'very high confidence' (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. We propose that temperatures at many highland localities are shifting towards the growth optimum of Batrachochytrium, thus encouraging outbreaks. With climate change promoting infectious disease and eroding biodiversity, the urgency of reducing greenhouse-gas concentrations is now undeniable. 相似文献
250.
P2X receptors are membrane ion channels activated by the binding of extracellular adenosine triphosphate (ATP). For years their functional significance was consigned to distant regions of the autonomic nervous system, but recent work indicates several further key roles, such as afferent signalling, chronic pain, and in autocrine loops of endothelial and epithelial cells. P2X receptors have a molecular architecture distinct from other ion channel protein families, and have several unique functional properties. 相似文献