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221.
The genome of the model beetle and pest Tribolium castaneum 总被引:6,自引:0,他引:6
Tribolium Genome Sequencing Consortium Richards S Gibbs RA Weinstock GM Brown SJ Denell R Beeman RW Gibbs R Beeman RW Brown SJ Bucher G Friedrich M Grimmelikhuijzen CJ Klingler M Lorenzen M Richards S Roth S Schröder R Tautz D Zdobnov EM Muzny D Gibbs RA Weinstock GM Attaway T Bell S Buhay CJ Chandrabose MN Chavez D Clerk-Blankenburg KP Cree A Dao M Davis C Chacko J Dinh H Dugan-Rocha S Fowler G Garner TT Garnes J Gnirke A Hawes A Hernandez J Hines S Holder M Hume J Jhangiani SN Joshi V Khan ZM 《Nature》2008,452(7190):949-955
Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory receptors, as well as P450 and other detoxification enzymes. Development in Tribolium is more representative of other insects than is Drosophila, a fact reflected in gene content and function. For example, Tribolium has retained more ancestral genes involved in cell-cell communication than Drosophila, some being expressed in the growth zone crucial for axial elongation in short-germ development. Systemic RNA interference in T. castaneum functions differently from that in Caenorhabditis elegans, but nevertheless offers similar power for the elucidation of gene function and identification of targets for selective insect control. 相似文献
222.
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
223.
Tarpey P Thomas S Sarvananthan N Mallya U Lisgo S Talbot CJ Roberts EO Awan M Surendran M McLean RJ Reinecke RD Langmann A Lindner S Koch M Jain S Woodruff G Gale RP Bastawrous A Degg C Droutsas K Asproudis I Zubcov AA Pieh C Veal CD Machado RD Backhouse OC Baumber L Constantinescu CS Brodsky MC Hunter DG Hertle RW Read RJ Edkins S O'Meara S Parker A Stevens C Teague J Wooster R Futreal PA Trembath RC Stratton MR Raymond FL Gottlob I 《Nature genetics》2006,38(11):1242-1244
Idiopathic congenital nystagmus is characterized by involuntary, periodic, predominantly horizontal oscillations of both eyes. We identified 22 mutations in FRMD7 in 26 families with X-linked idiopathic congenital nystagmus. Screening of 42 singleton cases of idiopathic congenital nystagmus (28 male, 14 females) yielded three mutations (7%). We found restricted expression of FRMD7 in human embryonic brain and developing neural retina, suggesting a specific role in the control of eye movement and gaze stability. 相似文献
224.
Dave JR Connors RA Genovese RF Whipple RA Chen RW DeFord SM Moran AV Tortella EC 《Cellular and molecular life sciences : CMLS》2007,64(21):2823-2828
The objective of this study was to determine levels of DNA fragmentation in blood leukocytes and parietal cortex from guinea
pigs following repeated lowlevel exposure to the chemical warfare nerve agent (CWNA) sarin. Guinea pigs were injected (s.c.)
once a day for 10 days with saline, or 0.1, 0.2, or 0.4 LD50 (50% mean lethal dose) sarin dissolved in sterile physiological saline. Blood and parietal cortex was collected after injection
at 0, 3, and 17 days recovery and evaluated for DNA fragmentation using single-cell gel electrophoresis (Comet assay). Cells
were imaged using comet analysis software and three parameters of DNA fragmentation measured: tail length, percent DNA in
the tail, and tail moment arm. Repeated low-dose exposure to sarin produced a dose-dependent response in leukocytes at 0 and
3 days post-exposure. There was a significant increase in all measures of DNA fragmentation at 0.2 and 0.4 LD50, but not at 0.1 LD50. There was no significant increase in DNA fragmentation in any of the groups at 17 days post-exposure. Sarin did not produce
a systematic dose-dependent response in parietal cortex at any of the time points. However, significant increases in DNA fragmentation
at 0.1 and 0.4 LD50 were observed at 0 and 3 days post-exposure. All measures of DNA fragmentation in both leukocytes and neurons returned to
control levels by 17 days post-exposure, indicating a small and non-persistent increase in DNA fragmentation following repeated
low-level exposure to sarin.
Received 23 July 2007; received after revision 23 August 2007; accepted 3 September 2007
Research was conducted in compliance with the Animal Welfare Act, and other Federal statutes and regulation relating to animals
and experiments involving animals and adheres to the principles
stated in the Guide for the Care and Use of Laboratory Animals, NIH publication 85-23. The views of the authors do not purport
to reflect the position of the Department of the Army or the Department of Defense (para 4-3), AR 360–365. 相似文献
225.
Norman PJ Abi-Rached L Gendzekhadze K Korbel D Gleimer M Rowley D Bruno D Carrington CV Chandanayingyong D Chang YH Crespí C Saruhan-Direskeneli G Fraser PA Hameed K Kamkamidze G Koram KA Layrisse Z Matamoros N Milà J Park MH Pitchappan RM Ramdath DD Shiau MY Stephens HA Struik S Verity DH Vaughan RW Tyan D Davis RW Riley EM Ronaghi M Parham P 《Nature genetics》2007,39(9):1092-1099
Interactions of killer cell immunoglobulin-like receptors (KIRs) with major histocompatibility complex (MHC) class I ligands diversify natural killer cell responses to infection. By analyzing sequence variation in diverse human populations, we show that the KIR3DL1/S1 locus encodes two lineages of polymorphic inhibitory KIR3DL1 allotypes that recognize Bw4 epitopes of protein">HLA-A and HLA-B and one lineage of conserved activating KIR3DS1 allotypes, also implicated in Bw4 recognition. Balancing selection has maintained these three lineages for over 3 million years. Variation was selected at D1 and D2 domain residues that contact HLA class I and at two sites on D0, the domain that enhances the binding of KIR3D to HLA class I. HLA-B variants that gained Bw4 through interallelic microconversion are also products of selection. A worldwide comparison uncovers unusual KIR3DL1/S1 evolution in modern sub-Saharan Africans. Balancing selection is weak and confined to D0, KIR3DS1 is rare and KIR3DL1 allotypes with similar binding sites predominate. Natural killer cells express the dominant KIR3DL1 at a high frequency and with high surface density, providing strong responses to cells perturbed in Bw4 expression. 相似文献
226.
227.
Stream denitrification across biomes and its response to anthropogenic nitrate loading 总被引:11,自引:0,他引:11
Mulholland PJ Helton AM Poole GC Hall RO Hamilton SK Peterson BJ Tank JL Ashkenas LR Cooper LW Dahm CN Dodds WK Findlay SE Gregory SV Grimm NB Johnson SL McDowell WH Meyer JL Valett HM Webster JR Arango CP Beaulieu JJ Bernot MJ Burgin AJ Crenshaw CL Johnson LT Niederlehner BR O'Brien JM Potter JD Sheibley RW Sobota DJ Thomas SM 《Nature》2008,452(7184):202-205
Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20-25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating that substantial sinks for nitrogen must exist in the landscape. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks. 相似文献
228.
本文研究了多变量最小拍控制原理,给出了多变量开环系统最小拍控制值的计算公式,对多变量闭环系统最小拍控制的物理意义作了进一步的论证.着重研究将最小拍控制用于抑制机械手振动的思想和控制方法的建立,并给出了在计算机上伤真及在装置上的试验结果. 相似文献
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