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991.
AGTR2 mutations in X-linked mental retardation 总被引:1,自引:0,他引:1
Vervoort VS Beachem MA Edwards PS Ladd S Miller KE de Mollerat X Clarkson K DuPont B Schwartz CE Stevenson RE Boyd E Srivastava AK 《Science (New York, N.Y.)》2002,296(5577):2401-2403
Two angiotensin II (Ang II)-specific receptors, AGTR1 and AGTR2, are expressed in the mammalian brain. Ang II actions on blood pressure regulation, water electrolyte balance, and hormone secretion are primarily mediated by AGTR1. The function of AGTR2 remains unclear. Here, we show that expression of the AGTR2 gene was absent in a female patient with mental retardation (MR) who had a balanced X;7 chromosomal translocation. Additionally, 8 of 590 unrelated male patients with MR were found to have sequence changes in the AGTR2 gene, including one frameshift and three missense mutations. These findings indicate a role for AGTR2 in brain development and cognitive function. 相似文献
992.
The structure of haplotype blocks in the human genome 总被引:1,自引:0,他引:1
Gabriel SB Schaffner SF Nguyen H Moore JM Roy J Blumenstiel B Higgins J DeFelice M Lochner A Faggart M Liu-Cordero SN Rotimi C Adeyemo A Cooper R Ward R Lander ES Daly MJ Altshuler D 《Science (New York, N.Y.)》2002,296(5576):2225-2229
Haplotype-based methods offer a powerful approach to disease gene mapping, based on the association between causal mutations and the ancestral haplotypes on which they arose. As part of The SNP Consortium Allele Frequency Projects, we characterized haplotype patterns across 51 autosomal regions (spanning 13 megabases of the human genome) in samples from Africa, Europe, and Asia. We show that the human genome can be parsed objectively into haplotype blocks: sizable regions over which there is little evidence for historical recombination and within which only a few common haplotypes are observed. The boundaries of blocks and specific haplotypes they contain are highly correlated across populations. We demonstrate that such haplotype frameworks provide substantial statistical power in association studies of common genetic variation across each region. Our results provide a foundation for the construction of a haplotype map of the human genome, facilitating comprehensive genetic association studies of human disease. 相似文献
993.
Goff SA Ricke D Lan TH Presting G Wang R Dunn M Glazebrook J Sessions A Oeller P Varma H Hadley D Hutchison D Martin C Katagiri F Lange BM Moughamer T Xia Y Budworth P Zhong J Miguel T Paszkowski U Zhang S Colbert M Sun WL Chen L Cooper B Park S Wood TC Mao L Quail P Wing R Dean R Yu Y Zharkikh A Shen R Sahasrabudhe S Thomas A Cannings R Gutin A Pruss D Reid J Tavtigian S Mitchell J Eldredge G Scholl T Miller RM Bhatnagar S Adey N Rubano T Tusneem N Robinson R Feldhaus J Macalma T Oliphant A 《Science (New York, N.Y.)》2002,296(5565):92-100
The genome of the japonica subspecies of rice, an important cereal and model monocot, was sequenced and assembled by whole-genome shotgun sequencing. The assembled sequence covers 93% of the 420-megabase genome. Gene predictions on the assembled sequence suggest that the genome contains 32,000 to 50,000 genes. Homologs of 98% of the known maize, wheat, and barley proteins are found in rice. Synteny and gene homology between rice and the other cereal genomes are extensive, whereas synteny with Arabidopsis is limited. Assignment of candidate rice orthologs to Arabidopsis genes is possible in many cases. The rice genome sequence provides a foundation for the improvement of cereals, our most important crops. 相似文献
994.
Calibrating the end-Permian mass extinction 总被引:2,自引:0,他引:2
Shen SZ Crowley JL Wang Y Bowring SA Erwin DH Sadler PM Cao CQ Rothman DH Henderson CM Ramezani J Zhang H Shen Y Wang XD Wang W Mu L Li WZ Tang YG Liu XL Liu LJ Zeng Y Jiang YF Jin YG 《Science (New York, N.Y.)》2011,334(6061):1367-1372
The end-Permian mass extinction was the most severe biodiversity crisis in Earth history. To better constrain the timing, and ultimately the causes of this event, we collected a suite of geochronologic, isotopic, and biostratigraphic data on several well-preserved sedimentary sections in South China. High-precision U-Pb dating reveals that the extinction peak occurred just before 252.28 ± 0.08 million years ago, after a decline of 2 per mil (‰) in δ(13)C over 90,000 years, and coincided with a δ(13)C excursion of -5‰ that is estimated to have lasted ≤20,000 years. The extinction interval was less than 200,000 years and synchronous in marine and terrestrial realms; associated charcoal-rich and soot-bearing layers indicate widespread wildfires on land. A massive release of thermogenic carbon dioxide and/or methane may have caused the catastrophic extinction. 相似文献
995.
Seife C 《Science (New York, N.Y.)》2003,302(5651):1651
996.
Climate-driven increases in global terrestrial net primary production from 1982 to 1999 总被引:15,自引:0,他引:15
Nemani RR Keeling CD Hashimoto H Jolly WM Piper SC Tucker CJ Myneni RB Running SW 《Science (New York, N.Y.)》2003,300(5625):1560-1563
Recent climatic changes have enhanced plant growth in northern mid-latitudes and high latitudes. However, a comprehensive analysis of the impact of global climatic changes on vegetation productivity has not before been expressed in the context of variable limiting factors to plant growth. We present a global investigation of vegetation responses to climatic changes by analyzing 18 years (1982 to 1999) of both climatic data and satellite observations of vegetation activity. Our results indicate that global changes in climate have eased several critical climatic constraints to plant growth, such that net primary production increased 6% (3.4 petagrams of carbon over 18 years) globally. The largest increase was in tropical ecosystems. Amazon rain forests accounted for 42% of the global increase in net primary production, owing mainly to decreased cloud cover and the resulting increase in solar radiation. 相似文献
997.
Yarovinsky F Zhang D Andersen JF Bannenberg GL Serhan CN Hayden MS Hieny S Sutterwala FS Flavell RA Ghosh S Sher A 《Science (New York, N.Y.)》2005,308(5728):1626-1629
Mammalian Toll-like receptors (TLRs) play an important role in the innate recognition of pathogens by dendritic cells (DCs). Although TLRs are clearly involved in the detection of bacteria and viruses, relatively little is known about their function in the innate response to eukaryotic microorganisms. Here we identify a profilin-like molecule from the protozoan parasite Toxoplasma gondii that generates a potent interleukin-12 (IL-12) response in murine DCs that is dependent on myeloid differentiation factor 88. T. gondii profilin activates DCs through TLR11 and is the first chemically defined ligand for this TLR. Moreover, TLR11 is required in vivo for parasite-induced IL-12 production and optimal resistance to infection, thereby establishing a role for the receptor in host recognition of protozoan pathogens. 相似文献
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