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541.
Stout D Chaminade T 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2012,367(1585):75-87
Long-standing speculations and more recent hypotheses propose a variety of possible evolutionary connections between language, gesture and tool use. These arguments have received important new support from neuroscientific research on praxis, observational action understanding and vocal language demonstrating substantial functional/anatomical overlap between these behaviours. However, valid reasons for scepticism remain as well as substantial differences in detail between alternative evolutionary hypotheses. Here, we review the current status of alternative 'gestural' and 'technological' hypotheses of language origins, drawing on current evidence of the neural bases of speech and tool use generally, and on recent studies of the neural correlates of Palaeolithic technology specifically. 相似文献
542.
Allyson K. Palmer Ming Xu Yi Zhu Tamar Pirtskhalava Megan M. Weivoda Christine M. Hachfeld Larissa G. Prata Theo H. van Dijk Esther Verkade Grace Casaclang‐Verzosa Kurt O. Johnson Hajrunisa Cubro Ewald J. Doornebal Mikolaj Ogrodnik Diana Jurk Michael D. Jensen Eduardo N. Chini Jordan D. Miller Aleksey Matveyenko Michael B. Stout Marissa J. Schafer Thomas A. White LaTonya J. Hickson Marco Demaria Vesna Garovic Joseph Grande Edgar A. Arriaga Folkert Kuipers Thomas von Zglinicki Nathan K. LeBrasseur Judith Campisi Tamar Tchkonia James L. Kirkland 《Aging cell》2019,18(3)
Adipose tissue inflammation and dysfunction are associated with obesity‐related insulin resistance and diabetes, but mechanisms underlying this relationship are unclear. Although senescent cells accumulate in adipose tissue of obese humans and rodents, a direct pathogenic role for these cells in the development of diabetes remains to be demonstrated. Here, we show that reducing senescent cell burden in obese mice, either by activating drug‐inducible “suicide” genes driven by the p16Ink4a promoter or by treatment with senolytic agents, alleviates metabolic and adipose tissue dysfunction. These senolytic interventions improved glucose tolerance, enhanced insulin sensitivity, lowered circulating inflammatory mediators, and promoted adipogenesis in obese mice. Elimination of senescent cells also prevented the migration of transplanted monocytes into intra‐abdominal adipose tissue and reduced the number of macrophages in this tissue. In addition, microalbuminuria, renal podocyte function, and cardiac diastolic function improved with senolytic therapy. Our results implicate cellular senescence as a causal factor in obesity‐related inflammation and metabolic derangements and show that emerging senolytic agents hold promise for treating obesity‐related metabolic dysfunction and its complications. 相似文献
543.
Luísa Gigante Carvalheiro Jacobus Christiaan Biesmeijer Gita Benadi Jochen Fründ Martina Stang Ignasi Bartomeus Christopher N. Kaiser‐Bunbury Mathilde Baude Sofia I. F. Gomes Vincent Merckx Katherine C. R. Baldock Andrew T. D. Bennett Ruth Boada Riccardo Bommarco Ralph Cartar Natacha Chacoff Juliana Dänhardt Lynn V. Dicks Carsten F. Dormann Johan Ekroos Kate S.E. Henson Andrea Holzschuh Robert R. Junker Martha Lopezaraiza‐Mikel Jane Memmott Ana Montero‐Castaño Isabel L. Nelson Theodora Petanidou Eileen F. Power Maj Rundlöf Henrik G. Smith Jane C. Stout Kehinde Temitope Teja Tscharntke Thomas Tscheulin Montserrat Vilà William E. Kunin 《Ecology letters》2014,17(11):1389-1399
Co‐flowering plant species commonly share flower visitors, and thus have the potential to influence each other's pollination. In this study we analysed 750 quantitative plant–pollinator networks from 28 studies representing diverse biomes worldwide. We show that the potential for one plant species to influence another indirectly via shared pollinators was greater for plants whose resources were more abundant (higher floral unit number and nectar sugar content) and more accessible. The potential indirect influence was also stronger between phylogenetically closer plant species and was independent of plant geographic origin (native vs. non‐native). The positive effect of nectar sugar content and phylogenetic proximity was much more accentuated for bees than for other groups. Consequently, the impact of these factors depends on the pollination mode of plants, e.g. bee or fly pollinated. Our findings may help predict which plant species have the greatest importance in the functioning of plant–pollination networks. 相似文献
544.
Agricultural Policies Exacerbate Honeybee Pollination Service Supply-Demand Mismatches Across Europe
Tom D. Breeze Bernard E. Vaissière Riccardo Bommarco Theodora Petanidou Nicos Seraphides Lajos Kozák Jeroen Scheper Jacobus C. Biesmeijer David Kleijn Steen Gyldenk?rne Marco Moretti Andrea Holzschuh Ingolf Steffan-Dewenter Jane C. Stout Meelis P?rtel Martin Zobel Simon G. Potts 《PloS one》2014,9(1)
Declines in insect pollinators across Europe have raised concerns about the supply of pollination services to agriculture. Simultaneously, EU agricultural and biofuel policies have encouraged substantial growth in the cultivated area of insect pollinated crops across the continent. Using data from 41 European countries, this study demonstrates that the recommended number of honeybees required to provide crop pollination across Europe has risen 4.9 times as fast as honeybee stocks between 2005 and 2010. Consequently, honeybee stocks were insufficient to supply >90% of demands in 22 countries studied. These findings raise concerns about the capacity of many countries to cope with major losses of wild pollinators and highlight numerous critical gaps in current understanding of pollination service supplies and demands, pointing to a pressing need for further research into this issue. 相似文献
545.
Melissa Braga Srinivasa T. Reddy Laurent Vergnes Shehla Pervin Victor Grijalva David Stout John David Xinmin Li Venina Tomasian Christopher B. Reid Keith C. Norris Sherin U. Devaskar Karen Reue Rajan Singh 《Journal of lipid research》2014,55(3):375-384
Follistatin (Fst) functions to bind and neutralize the activity of members of the transforming growth factor-β superfamily. Fst has a well-established role in skeletal muscle, but we detected significant Fst expression levels in interscapular brown and subcutaneous white adipose tissue, and further investigated its role in adipocyte biology. Fst expression was induced during adipogenic differentiation of mouse brown preadipocytes and mouse embryonic fibroblasts (MEFs) as well as in cold-induced brown adipose tissue from mice. In differentiated MEFs from Fst KO mice, the induction of brown adipocyte proteins including uncoupling protein 1, PR domain containing 16, and PPAR gamma coactivator-1α was attenuated, but could be rescued by treatment with recombinant FST. Furthermore, Fst enhanced thermogenic gene expression in differentiated mouse brown adipocytes and MEF cultures from both WT and Fst KO groups, suggesting that Fst produced by adipocytes may act in a paracrine manner. Our microarray gene expression profiling of WT and Fst KO MEFs during adipogenic differentiation identified several genes implicated in lipid and energy metabolism that were significantly downregulated in Fst KO MEFs. Furthermore, Fst treatment significantly increases cellular respiration in Fst-deficient cells. Our results implicate a novel role of Fst in the induction of brown adipocyte character and regulation of energy metabolism. 相似文献
546.
Hoge KM Ryan ED Costa PB Herda TJ Walter AA Stout JR Cramer JT 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(10):2618-2626
The purpose of the present study was to examine musculotendinous stiffness (MTS) and ankle joint range of motion (ROM) in men and women after an acute bout of passive stretching. Thirteen men (mean ± SD age = 21 ± 2 years; body mass = 79 ± 15 kg; and height = 177 ± 7 cm) and 19 women (21 ± 3 years; 61 ± 9 kg; 165 ± 8 cm) completed stretch tolerance tests to determine MTS and ROM before and after a stretching protocol that consisted of 9 repetitions of passive, constant-torque stretching. The women were all tested during menses. Each repetition was held for 135 seconds. The results indicated that ROM increased after the stretching for the women (means ± SD pre to post: 109.39° ± 10.16° to 116.63° ± 9.63°; p ≤ 0.05) but not for the men (111.79° ± 6.84° to 113.93° ± 8.15°; p > 0.05). There were no stretching-induced changes in MTS (women's pre to postchange in MTS: -0.35 ± 0.38; men's MTS: +0.17 ± 0.40; p > 0.05), but MTS was higher for the men than for the women (MTS: 1.34 ± 0.41 vs. 0.97 ± 0.38; p ≤ 0.05). electromyographic amplitude for the soleus and medial gastrocnemius during the stretching tests was unchanged from pre to poststretching (p > 0.05); however, it increased with joint angle during the passive movements (p ≤ 0.05). Passively stretching the calf muscles increased stretch tolerance in women but not in men. But the stretching may not have affected the viscoelastic properties of the muscles. Practitioners may want to consider the possible gender differences in passive stretching responses and that increases in ROM may not always reflect decreases in MTS. 相似文献
547.
E. Paige Stout Jacques Prudhomme Karine Le Roch Craig R. Fairchild Scott G. Franzblau William Aalbersberg Mark E. Hay Julia Kubanek 《Bioorganic & medicinal chemistry letters》2010,20(19):5662-5665
Three antimalarial meroditerpenes have been isolated from two Fijian red macroalgae. The absolute stereochemistry of callophycolide A (1), a unique macrolide from Callophycus serratus, was determined using a combination of Mosher’s ester analysis, circular dichroism analysis with a dimolybdenum tetraacetate complex, and conformational analysis using NOEs. In addition, two known tocopherols, β-tocopherylhydroquinone (4) and δ-tocopherylhydroquinone (5), were isolated from Amphiroa crassa. By oxidizing 5 to the corresponding δ-tocopherylquinone (6), antimalarial activity against the human malaria parasite Plasmodium falciparum was increased by more than 20-fold. 相似文献
548.
Travis W. Beck Terry J. Housh Joel T. Cramer Jeffrey R. Stout Eric D. Ryan Trent J. Herda Pablo B. Costa Jason M. Defreitas 《Journal of electromyography and kinesiology》2009,19(4):660-666
The purpose of this study was to use a wavelet-based signal processing technique to examine the influence of electrode placement over the innervation zone (IZ) on the shape of the electromyographic (EMG) frequency spectrum. Ten healthy males (mean ± SD age = 23.6 ± 3.0 years) performed isometric muscle actions of the dominant leg extensors at 10%, 40%, 70%, and 100% of the maximum voluntary contraction (MVC). Surface EMG signals were detected simultaneously from the vastus lateralis with two bipolar electrode arrangements. One of the electrode arrangements had its center point located directly over the IZ, while the other arrangement had its center point distal to the IZ (i.e., 20 mm away). All EMG signals were processed with a wavelet-based procedure. The results showed that for all isometric torque levels, the EMG signals from the distal electrode arrangement demonstrated greater total intensity values than those for the IZ arrangement for frequencies ranging from approximately 2 to 110 Hz. There were no consistent differences, however, between the IZ and distal electrode arrangements for total EMG intensity values above 110 Hz. Thus, these findings indicated that electrode placement over the IZ affected primarily the low-, rather than the high-frequency portion of the EMG frequency spectrum. 相似文献
549.
550.