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901.
902.
High mutation rates have driven extensive structural polymorphism among human Y chromosomes 总被引:15,自引:0,他引:15
Repping S van Daalen SK Brown LG Korver CM Lange J Marszalek JD Pyntikova T van der Veen F Skaletsky H Page DC Rozen S 《Nature genetics》2006,38(4):463-467
Although much structural polymorphism in the human genome has been catalogued, the kinetics of underlying change remain largely unexplored. Because human Y chromosomes are clonally inherited, it has been possible to capture their detailed relationships in a robust, worldwide genealogical tree. Examination of structural variation across this tree opens avenues for investigating rates of underlying mutations. We selected one Y chromosome from each of 47 branches of this tree and searched for large-scale variation. Four chromosomal regions showed extensive variation resulting from numerous large-scale mutations. Within the tree encompassed by the studied chromosomes, the distal-Yq heterochromatin changed length > or = 12 times, the TSPY gene array changed length > or = 23 times, the 3.6-Mb IR3/IR3 region changed orientation > or = 12 times and the AZFc region was rearranged > or = 20 times. After determining the total time spanned by all branches of this tree (approximately 1.3 million years or 52,000 generations), we converted these mutation counts to lower bounds on rates: > or = 2.3 x 10(-4), > or = 4.4 x 10(-4), > or = 2.3 x 10(-4) and > or = 3.8 x 10(-4) large-scale mutations per father-to-son Y transmission, respectively. Thus, high mutation rates have driven extensive structural polymorphism among human Y chromosomes. At the same time, we found limited variation in the copy number of Y-linked genes, which raises the possibility of selective constraints. 相似文献
903.
Service S DeYoung J Karayiorgou M Roos JL Pretorious H Bedoya G Ospina J Ruiz-Linares A Macedo A Palha JA Heutink P Aulchenko Y Oostra B van Duijn C Jarvelin MR Varilo T Peddle L Rahman P Piras G Monne M Murray S Galver L Peltonen L Sabatti C Collins A Freimer N 《Nature genetics》2006,38(5):556-560
The genome-wide distribution of linkage disequilibrium (LD) determines the strategy for selecting markers for association studies, but it varies between populations. We assayed LD in large samples (200 individuals) from each of 11 well-described population isolates and an outbred European-derived sample, using SNP markers spaced across chromosome 22. Most isolates show substantially higher levels of LD than the outbred sample and many fewer regions of very low LD (termed 'holes'). Young isolates known to have had relatively few founders show particularly extensive LD with very few holes; these populations offer substantial advantages for genome-wide association mapping. 相似文献
904.
905.
Herring CD Raghunathan A Honisch C Patel T Applebee MK Joyce AR Albert TJ Blattner FR van den Boom D Cantor CR Palsson BØ 《Nature genetics》2006,38(12):1406-1412
We applied whole-genome resequencing of Escherichia coli to monitor the acquisition and fixation of mutations that conveyed a selective growth advantage during adaptation to a glycerol-based growth medium. We identified 13 different de novo mutations in five different E. coli strains and monitored their fixation over a 44-d period of adaptation. We obtained proof that the observed spontaneous mutations were responsible for improved fitness by creating single, double and triple site-directed mutants that had growth rates matching those of the evolved strains. The success of this new genome-scale approach indicates that real-time evolution studies will now be practical in a wide variety of contexts. 相似文献
906.
Sandilands A Terron-Kwiatkowski A Hull PR O'Regan GM Clayton TH Watson RM Carrick T Evans AT Liao H Zhao Y Campbell LE Schmuth M Gruber R Janecke AR Elias PM van Steensel MA Nagtzaam I van Geel M Steijlen PM Munro CS Bradley DG Palmer CN Smith FJ McLean WH Irvine AD 《Nature genetics》2007,39(5):650-654
We recently reported two common filaggrin (FLG) null mutations that cause ichthyosis vulgaris and predispose to eczema and secondary allergic diseases. We show here that these common European mutations are ancestral variants carried on conserved haplotypes. To facilitate comprehensive analysis of other populations, we report a strategy for full sequencing of this large, highly repetitive gene, and we describe 15 variants, including seven that are prevalent. All the variants are either nonsense or frameshift mutations that, in representative cases, resulted in loss of filaggrin production in the epidermis. In an Irish case-control study, the five most common European mutations showed a strong association with moderate-to-severe childhood eczema (chi2 test: P = 2.12 x 10(-51); Fisher's exact test: heterozygote odds ratio (OR) = 7.44 (95% confidence interval (c.i.) = 4.9-11.3), and homozygote OR = 151 (95% c.i. = 20-1,136)). We found three additional rare null mutations in this case series, suggesting that the genetic architecture of filaggrin-related atopic dermatitis consists of both prevalent and rare risk alleles. 相似文献
907.
Steinthorsdottir V Thorleifsson G Reynisdottir I Benediktsson R Jonsdottir T Walters GB Styrkarsdottir U Gretarsdottir S Emilsson V Ghosh S Baker A Snorradottir S Bjarnason H Ng MC Hansen T Bagger Y Wilensky RL Reilly MP Adeyemo A Chen Y Zhou J Gudnason V Chen G Huang H Lashley K Doumatey A So WY Ma RC Andersen G Borch-Johnsen K Jorgensen T van Vliet-Ostaptchouk JV Hofker MH Wijmenga C Christiansen C Rader DJ Rotimi C Gurney M Chan JC Pedersen O Sigurdsson G Gulcher JR Thorsteinsdottir U Kong A 《Nature genetics》2007,39(6):770-775
908.
den Hollander AI Koenekoop RK Mohamed MD Arts HH Boldt K Towns KV Sedmak T Beer M Nagel-Wolfrum K McKibbin M Dharmaraj S Lopez I Ivings L Williams GA Springell K Woods CG Jafri H Rashid Y Strom TM van der Zwaag B Gosens I Kersten FF van Wijk E Veltman JA Zonneveld MN van Beersum SE Maumenee IH Wolfrum U Cheetham ME Ueffing M Cremers FP Inglehearn CF Roepman R 《Nature genetics》2007,39(7):889-895
909.
Lennart Zabeau Cathy J. Jensen Sylvie Seeuws Koen Venken Annick Verhee Dominiek Catteeuw Geert van Loo Hui Chen Ken Walder Jacob Hollis Simon Foote Margaret J. Morris José Van der Heyden Frank Peelman Brian J. Oldfield Justin P. Rubio Dirk Elewaut Jan Tavernier 《Cellular and molecular life sciences : CMLS》2015,72(3):629-644
910.
We investigate learning dynamics in the formation of household inflation expectations in the six largest euro area countries. Our findings reveal heterogeneity in the learning rules that European households use to forecast inflation. We also find pronounced heterogeneity in the way consumers process new data. These differences vary not only across countries but also over time, suggesting that the learning behavior of households is state dependent. 相似文献