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991.
James Wickham Tania Pizzari Katie Stansfeld Amanda Burnside Lyn Watson 《Journal of electromyography and kinesiology》2010,20(2):212-222
The purpose of this experiment was to obtain electromyographic (EMG) activity from a sample of healthy shoulders to allow a reference database to be developed and used for comparison with pathological shoulders. Temporal and intensity shoulder muscle activation characteristics during a coronal plane abduction/adduction movement were evaluated in the dominant healthy shoulder of 24 subjects. Surface and intramuscular fine wire electrodes recorded EMG activity from 15 shoulder muscles (deltoid × 3, trapezius × 3, subscapularis × 2, latissimus dorsi, pectoralis major, pectoralis minor, supraspinatus, infraspinatus, serratus anterior and rhomboids) at 2000 Hz for 10 s whilst each subject performed 10 dynamic coronal plane abduction/adduction movements from 0° to 166° to 0° with a light dumbbell. Results revealed that supraspinatus (?.102 s before movement onset) initiated the movement with middle trapezius (?.019 s) and middle deltoid (?.014 s) also activated before the movement onset. Similar patterns were also found in the time of peak amplitude and %MVC with a pattern emerging where the prime movers (supraspinatus and middle deltoid) were among the first to reach peak amplitude or display the highest %MVC values. In conclusion, the most reproducible patterns of activation arose from the more prime mover muscle sites in all EMG variables analysed and although variability was present, there emerged ‘invariant characteristics’ that were considered ‘normal’ for this group of non pathological shoulders. The authors believe that the methodology and certain parts of the analysis in this study can be duplicated and used by future researchers who require a reference database of muscle activity for use as a control group in comparisons to their respective pathological shoulder group. 相似文献
992.
Rita Barallon Steven R. Bauer John Butler Amanda Capes-Davis Wilhelm G. Dirks Eugene Elmore Manohar Furtado Margaret C. Kline Arihiro Kohara Georgyi V. Los Roderick A. F. MacLeod John R. W. Masters Mark Nardone Roland M. Nardone Raymond W. Nims Paul J. Price Yvonne A. Reid Jaiprakash Shewale Gregory Sykes Anton F. Steuer Douglas R. Storts Jim Thomson Zenobia Taraporewala Christine Alston-Roberts Liz Kerrigan 《In vitro cellular & developmental biology. Animal》2010,46(9):727-732
Cell misidentification and cross-contamination have plagued biomedical research for as long as cells have been employed as research tools. Examples of misidentified cell lines continue to surface to this day. Efforts to eradicate the problem by raising awareness of the issue and by asking scientists voluntarily to take appropriate actions have not been successful. Unambiguous cell authentication is an essential step in the scientific process and should be an inherent consideration during peer review of papers submitted for publication or during review of grants submitted for funding. In order to facilitate proper identity testing, accurate, reliable, inexpensive, and standardized methods for authentication of cells and cell lines must be made available. To this end, an international team of scientists is, at this time, preparing a consensus standard on the authentication of human cells using short tandem repeat (STR) profiling. This standard, which will be submitted for review and approval as an American National Standard by the American National Standards Institute, will provide investigators guidance on the use of STR profiling for authenticating human cell lines. Such guidance will include methodological detail on the preparation of the DNA sample, the appropriate numbers and types of loci to be evaluated, and the interpretation and quality control of the results. Associated with the standard itself will be the establishment and maintenance of a public STR profile database under the auspices of the National Center for Biotechnology Information. The consensus standard is anticipated to be adopted by granting agencies and scientific journals as appropriate methodology for authenticating human cell lines, stem cells, and tissues. 相似文献
993.
Genetic Analysis and Molecular Mapping of a Novel Gene Conferring Resistance to Rice Stripe Virus 总被引:1,自引:0,他引:1
Feng Zhao Zhijun Cai Tiezhu Hu Haigen Yao Li Wang Na Dong Bin Wang Zhengang Ru Wenxue Zhai 《Plant Molecular Biology Reporter》2010,28(3):512-518
Rice stripe virus (RSV) is one of the most damaging diseases affecting rice in East Asia. Rice variety 502 is highly resistant
to RSV, while variety 5112 is extremely susceptible. Field statistical data revealed that all “502 × 5112” F1 individuals were resistant to RSV and the ratio of resistant to susceptible plants was 3:1 in the F2 population and 1:1 in the BC1F1 population. These results indicated that a dominant gene, designated RSV1, controlled the resistance. Simple sequence repeat (SSR) analysis was subsequently carried out in an F2 population. Sixty SSR markers evenly distributed on the 12 rice chromosomes were screened and tested. Two markers, RM229
and RM206, showed linkage with RSV1. Based on this result, six SSR markers flanking RM229 and RM206 were further selected and tested. Results indicated that
SSR markers RM457 and RM473E were linked to RSV1 with a genetic distance of 4.5 and 5.0 cM, respectively. All of the four SSR markers (RM229, RM473E, RM457 and RM206) linked
to RSV1 were all located on chromosome 11, therefore RSV1 should be located on chromosome 11 also. In order to find some new markers more closely linked to the RSV1 gene, sequence-related amplified polymorphism (SRAP) analysis was performed. A total of 30 SRAP primer-pairs were analyzed,
and one marker SR1 showed linkage with RSV1 at a genetic distance of 2.9 cM. Finally, RSV1 gene was mapped on chromosome 11 between SSR markers RM457 and SRAP marker SR1 with a genetic distance of 4.5 cM and 2.9 cM,
respectively. 相似文献
994.
995.
William J. Mitsch Amanda Nahlik Piotr Wolski Blanca Bernal Li Zhang Lars Ramberg 《Wetlands Ecology and Management》2010,18(5):573-586
This paper summarizes the importance of climate on tropical wetlands. Regional hydrology and carbon dynamics in many of these
wetlands could shift with dramatic changes in these major carbon storages if the inter-tropical convergence zone (ITCZ) were
to change in its annual patterns. The importance of seasonal pulsing hydrology on many tropical wetlands, which can be caused
by watershed activities, orographic features, or monsoonal pulses from the ITCZ, is illustrated by both annual and 30-year
patterns of hydrology in the Okavango Delta in southern Africa. Current studies on carbon biogeochemistry in Central America
are attempting to determine the rates of carbon sequestration in tropical wetlands compared to temperate wetlands and the
effects of hydrologic conditions on methane generation in these wetlands. Using the same field and lab techniques, we estimated
that a humid tropical wetland in Costa Rica accumulated 255 g C m−2 year−1 in the past 42 years, 80% more than a similar temperate wetland in Ohio that accumulated 142 g C m−2 year−1 over the same period. Methane emissions averaged 1,080 mg-C m−2 day−1 in a seasonally pulsed wetland in western Costa Rica, a rate higher than methane emission rates measured over the same period
from humid tropic wetlands in eastern Costa Rica (120–278 mg-C m−2 day−1). Tropical wetlands are often tuned to seasonal pulses of water caused by the seasonal movement of the ITCZ and are the most
likely to be have higher fire frequency and changed methane emissions and carbon oxidation if the ITCZ were to change even
slightly. 相似文献
996.
Junhua Xiao Yinming Liang Kai Li Yuxuan Zhou Wenqian Cai Yumei Zhou Ying Zhao Zhenghong Xing Guoqiang Chen Li Jin 《Mammalian genome》2010,21(7-8):370-376
The mouse is an irreplaceable model for understanding the precise genetic mechanisms of mammalian physiological pathways. Thousands of quantitative trait loci (QTLs) have been mapped onto the mouse genome during the last two decades. However, only a few genes’ underlying complex traits have been successfully identified, and rapid fine mapping of QTL genes still remains a challenge for mouse geneticists. Currently, the Collaborative Cross (CC) has proceeded to the goal of establishing more than 1,000 recombinant inbred strains for the sub-centimorgan mapping resolution of QTL loci. In this article, a novel complementary strategy, designated as population of specific chromosome substitution strains or PSCSS, is proposed for rapid fine mapping of QTLs on the substituted chromosome. One specific chromosome (Chr 1) of recipient mouse strain C57BL/6 J has been substituted by homologous counterparts from five different inbred strains (C3H/He, FVB/N, AKR, NOD/LtJ, NZW/LacJ), an outbred line Kunmin mouse in China, and 23 wild mice captured in different localities. The primary genetic studies on the structure of these wild donor chromosomes (Chr 1) show that these donor chromosomes harbor extensive genetic polymorphisms, with a high density of SNP distribution, abundant variations of STR alleles, and a high level of historical recombination accumulation. These specific chromosome substitution strains eventually form a special population that has the identical genetic background of the recipient strain and differs only in the donor chromosomes. With simple association studies, known QTLs on the donor chromosome can be rapidly mapped in high resolution without requirement of further crosses. This approach, taking advantage of the extensive genetic polymorphisms of wild resources and chromosome substitution strategy, brings a new outlook for genetic dissection of complex traits. 相似文献
997.
The identification of a series of novel, soluble non-peptidic neuropeptide Y Y2 receptor antagonists
Lunniss GE Barnes AA Barton N Biagetti M Bianchi F Blowers SM Caberlotto LL Emmons A Holmes IP Montanari D Norris R Puckey GV Walters DJ Watson SP Willis J 《Bioorganic & medicinal chemistry letters》2010,20(24):7341-7344
The identification and subsequent optimisation of a selective non-peptidic NPY Y2 antagonist series is described. This led to the development of amine 2, a selective, soluble NPY Y2 receptor antagonist with enhanced CNS exposure. 相似文献
998.
Nilantha Sirisoma Azra Pervin Hong Zhang Songchun Jiang J. Adam Willardsen Mark B. Anderson Gary Mather Christopher M. Pleiman Shailaja Kasibhatla Ben Tseng John Drewe Sui Xiong Cai 《Bioorganic & medicinal chemistry letters》2010,20(7):2330-2334
As a continuation of our efforts to discover and develop apoptosis inducing N-methyl-4-(4-methoxyanilino)quinazolines as novel anticancer agents, we explored substitution at the 5-, 6-, 7-positions of the quinazoline and replacement of the quinazoline by other nitrogen-containing heterocycles. A small group at the 5-position was found to be well tolerated. At the 6-position a small group like an amino was preferred. Substitution at the 7-position was tolerated much less than at the 6-position. Replacing the carbon at the 8-position or both the 5- and 8-positions with nitrogen led to about 10-fold reductions in potency. Replacement of the quinazoline ring with a quinoline, a benzo[d][1,2,3]triazine, or an isoquinoline ring showed that the nitrogen at the 1-position is important for activity, while the carbon at the 2-position can be replaced by a nitrogen and the nitrogen at the 3-position can be replaced by a carbon. Through the SAR study, several 5- or 6-substituted analogs, such as 2a and 2c, were found to have potencies approaching that of lead compound N-(4-methoxyphenyl)-N,2-dimethylquinazolin-4-amine (1g, EP128495, MPC-6827, Azixa®). 相似文献
999.
Jiaqiang Cai D. Jonathan Bennett Zoran Rankovic Maureen Dempster Xavier Fradera Jonathan Gillespie Iain Cumming William Finlay Mark Baugh Sylviane Boucharens John Bruin Kenneth S. Cameron William Hamilton Jennifer Kerr Emma Kinghorn George McGarry John Robinson Paul Scullion Joost C.M. Uitdehaag Mario van Zeeland Eric Nicolai 《Bioorganic & medicinal chemistry letters》2010,20(15):4447-4450
Starting from previously disclosed equally potent cathepsin K and S inhibitor 4-propyl-6-(3-trifluoromethylphenyl)pyrimidine-2-carbonitrile 1, a novel 2-phenyl-9H-purine-6-carbonitrile scaffold was identified to provide potent and selective cathepsin S inhibitors. 相似文献
1000.
Laszlo Revesz Achim Schlapbach Reiner Aichholz Janet Dawson Roland Feifel Stuart Hawtin Amanda Littlewood-Evans Guido Koch Markus Kroemer Henrik Möbitz Clemens Scheufler Juraj Velcicky Christine Huppertz 《Bioorganic & medicinal chemistry letters》2010,20(15):4719-4723
Spirocyclopropane- and spiroazetidine-substituted tetracycles 13D–E and 16A are described as orally active MK2 inhibitors. The spiroazetidine derivatives are potent MK2 inhibitors with IC50 <3 nM and inhibit the release of TNFα (IC50<0.3 μM) from hPBMCs and hsp27 phosphorylation in anisomycin stimulated THP-1 cells. The spirocyclopropane analogues are less potent against MK2 (IC50 = 0.05–0.23 μM), less potent in cells (IC50 <1.1 μM), but show good oral absorption. Compound 13E (100 mg/kg po; bid) showed oral activity in rAIA and mCIA, with significant reduction of swelling and histological score. 相似文献