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101.
A retained intron in the 3′‐UTR of Calm3 mRNA mediates its Staufen2‐ and activity‐dependent localization to neuronal dendrites
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102.
Background
Recently, activation-dependant structural brain plasticity in humans has been demonstrated in adults after three months of training a visio-motor skill. Learning three-ball cascade juggling was associated with a transient and highly selective increase in brain gray matter in the occipito-temporal cortex comprising the motion sensitive area hMT/V5 bilaterally. However, the exact time-scale of usage-dependant structural changes occur is still unknown. A better understanding of the temporal parameters may help to elucidate to what extent this type of cortical plasticity contributes to fast adapting cortical processes that may be relevant to learning.Principal Findings
Using a 3 Tesla scanner and monitoring whole brain structure we repeated and extended our original study in 20 healthy adult volunteers, focussing on the temporal aspects of the structural changes and investigated whether these changes are performance or exercise dependant. The data confirmed our earlier observation using a mean effects analysis and in addition showed that learning to juggle can alter gray matter in the occipito-temporal cortex as early as after 7 days of training. Neither performance nor exercise alone could explain these changes.Conclusion
We suggest that the qualitative change (i.e. learning of a new task) is more critical for the brain to change its structure than continued training of an already-learned task. 相似文献103.
Mahasweta Saha Francisco R. Barboza Paul J. Somerfield Balsam Al‐Janabi Miriam Beck Janina Brakel Maysa Ito Christian Pansch Jennifer C. Nascimento‐Schulze Stina Jakobsson Thor Florian Weinberger Yvonne Sawall 《Global Change Biology》2020,26(2):417-430
Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticity. 相似文献
104.
Janina Gajc-Wolska Henryk Skąpski Jolanta A. Szymczak 《Acta Physiologiae Plantarum》2000,22(3):369-373
The physical and sensory characteristics of tomato fruits (cf. Gajc-Wolska et al.: Physical and sensory characteristics of the fruits …, this issue) were supplemented by total sugars and titratable acid
analysis and flavor. The instrumental and sensory methods were highly statistically correlated. Comparison of cultivars always
requires that physical and chemical analysis of tomato fruit quality should always include results of sensory evaluation. 相似文献
105.
106.
L-2,4-Diaminobutyric acid (Dab) reacts with K2PtCl4 yielding PtCl2(N,O-Dab), which rearranges to PtCl2(N,N-Dab). Reaction with L-ornithine and L-lysine yields the corresponding PtCl2(N,O-Orn) and PtCl2(N,O-Lys), respectively, whereas reaction with 4,5-diaminovaleric acid (Dav) yields PtCl2(N,N- Dav). 相似文献
107.
Macronuclear differentiation in conjugating pairs of Tetrahymena treated with the antitubulin drug nocodazole 总被引:2,自引:0,他引:2
Andrzej Kaczanowski Malgorzata Ramel Janina Kaczanowska Denys Wheatley 《Experimental cell research》1991,195(2):330-337
During Tetrahymena conjugation gamic nuclei (pronuclei) are produced, reciprocally exchanged, and fused in each mate. The synkaryon divides twice; the two anterior nuclei develop into new macronuclei while the two posterior nuclei become micronuclei. The postzygotic divisions were blocked with the antitubulin drug nocodazole (ND). Then pronuclei (gamic nuclei) developed directly into macronuclear anlagen (primordial macronuclei), inducing amicronucleate cells with two anlagen, or, rarely, cells with one anlagen and one micronucleus. ND had a similar effect on cells that passed the first postzygotic division inducing amicronucleate cells with two anlagen, while cells treated with ND at the synkarya stage produced only one large anlage. Different intracytoplasmic positioning of the nuclei treated with ND (pronuclei, synkarya and two products of the first division) shows that most of cell cytoplasm is competent for inducing macronuclear development. Only posteriorly positioned nuclei--products of the second postzygotic division--remain micronuclei. The total cell DNA content, measured cytophotometrically in control and in ND-induced amicronucleate conjugant cells with one and two anlagen, was similar in all three samples at 12 h of conjugation. Eventually, at 24 h this content was about 2 pg (8 C) per anlagen both in nonrefed control and in amicronucleate exconjugants. Therefore "large" nuclei developing in the presence of ND were true macronuclear anlagen. 相似文献
108.
The effects of amphotericin B on lipid metabolism in cultured human skin fibroblasts 总被引:4,自引:0,他引:4
Richard A. Levy Richard E. Ostlund Jr. Janina Brajtburg 《In vitro cellular & developmental biology. Plant》1985,21(1):26-31
Summary Amphotericin B inhibits hydroxymethylglutarylcoenzyme A (HMGCoA) reductase activity and incorporation of [3H]acetate into sterols and fatty acids of human skin fibroblasts. Delivery of cholesterol to cells via the low density lipoprotein
receptor pathway is not altered. The effects of amphotericin B on cell lipid metabolism are partially reversed by both potassium
and insulin.
Portions of this work were presented at the Southern Regional Meeting of the American Federation for Clinical Research, January
1983. 相似文献
109.