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21.
Pedro Monterroso Paulo Célio Alves Pablo Ferreras 《Ethology : formerly Zeitschrift fur Tierpsychologie》2013,119(12):1044-1056
The activity patterns exhibited by animals are shaped by evolution, but additionally fine‐tuned by flexible responses to the environment. Predation risk and resource availability are environmental cues which influence the behavioural decisions that make both predators and prey engage in activity bursts, and depending on their local importance, can be strong enough to override the endogenous regulation of an animals’ circadian clock. In Southern Europe, wherever the European rabbit (Oryctolagus cuniculus) is abundant, it is the main prey of most mammalian mesopredators, and rodents are generally the alternative prey. We evaluated the bidirectional relation between the diel activity strategies of these mammalian mesopredators and prey coexisting in south‐western Europe. Results revealed that even though predation risk enforced by mammalian mesocarnivores during night‐time was approximately twice and five times higher than during twilight and daytime, respectively, murids consistently displayed unimodal nocturnal behaviour. Conversely, the European rabbits exhibited a bimodal pattern that peaked around sunrise and sunset. Despite the existence of some overlap between the diel rhythms of mesocarnivores and rabbits, their patterns were not synchronized. We suggest that the environmental stressors in our study areas are not severe enough to override the endogenous regulation of the circadian cycle in murids. European rabbits, however, are able to suppress their biological tendency for nocturnality by selecting a predominantly crepuscular pattern. In spite of the higher energetic input, mesocarnivores do not completely track rabbits’ activity pattern. They rather track rodents’ activity. We propose that these systems have probably evolved towards a situation where some degree of activity during high‐risk periods benefits the overall prey population survival, while the accessibility to sufficient prey prevents predators to completely track them. 相似文献
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Chang KH Multani PS Sun KH Vincent F de Pablo Y Ghosh S Gupta R Lee HP Lee HG Smith MA Shah K 《Molecular biology of the cell》2011,22(9):1452-1462
Nuclear fragmentation is a common feature in many neurodegenerative diseases, including Alzheimer's disease (AD). In this study, we show that nuclear lamina dispersion is an early and irreversible trigger for cell death initiated by deregulated Cdk5, rather than a consequence of apoptosis. Cyclin-dependent kinase 5 (Cdk5) activity is significantly increased in AD and contributes to all three hallmarks: neurotoxic amyloid-β (Aβ), neurofibrillary tangles (NFT), and extensive cell death. Using Aβ and glutamate as the neurotoxic stimuli, we show that deregulated Cdk5 induces nuclear lamina dispersion by direct phosphorylation of lamin A and lamin B1 in neuronal cells and primary cortical neurons. Phosphorylation-resistant mutants of lamins confer resistance to nuclear dispersion and cell death on neurotoxic stimulation, highlighting this as a major mechanism for neuronal death. Rapid alteration of lamin localization pattern and nuclear membrane change are further supported by in vivo data using an AD mouse model. After p25 induction, the pattern of lamin localization was significantly altered, preceding neuronal death, suggesting that it is an early pathological event in p25-inducible transgenic mice. Importantly, lamin dispersion is coupled with Cdk5 nuclear localization, which is highly neurotoxic. Inhibition of nuclear dispersion rescues neuronal cells from cell death, underscoring the significance of this event to Cdk5-mediated neurotoxicity. 相似文献
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Juliana Stein Silvina C. Pessino Eric J. Martínez María Pía Rodriguez Lorena A. Siena Camilo L. Quarin Juan Pablo Amelio Ortiz 《Molecular breeding : new strategies in plant improvement》2007,20(2):153-166
Paspalum notatum Flügge is a warm-season forage grass with mainly diploid (2n = 20) and autotetraploid (2n = 40) representatives. Diploid
races reproduce sexually and require crosspollination due to a self-incompatible mating system, while autotetraploids reproduce
by aposporous apomixis. The objectives of this work were to develop a genetic linkage map of Paspalum notatum Flügge at the tetraploid level, identify the linkage/s group/s associated with apomixis and carry out a general characterization
of its mode of inheritance. A pseudo test-cross F1 family of 113 individuals segregating for the mode of reproduction was obtained by crossing a synthetic completely sexual
tetraploid plant (Q4188) as female parent with a natural aposporous individual (Q4117) as pollen donor. Map construction was
based on single-dose markers (SDAFs) segregating from both parents. Two linkage maps (female and male) were constructed. Within
each map, homologous groups were assembled by detecting repulsion-phase linked SDAFs. Putative Q4188 and Q4117 homolog groups
were identified by mapping shared single dose markers (BSDF). The Q4188 map consisted of 263 markers distributed on 26 co-segregation
groups over a total genetic distance of 1.590.6 cM, while the Q4117 map contained 216 loci dispersed on 39 co-segregation
groups along 2.265.7 cM, giving an estimated genome coverage of 88% and 83%, respectively. Seven and 12 putative homologous
chromosomes were detected within Q4188 and Q4117 maps, respectively. Afterward, ten female and male homologous chromosomes
were identified by mapping BSDFs. In the Q4117 map, a single linkage group was associated with apospory. It was characterized
by restriction in recombination and preferential chromosome pairing. A BPSD marker mapping within this group allowed the detection
of the female homolog and the putative four male groups of the set carrying apospory. 相似文献
26.
Jesús Vaquero Mercedes Zurita Miguel A. Rico Concepcion Aguayo Celia Bonilla Esperanza Marin Noemi Tapiador Marta Sevilla David Vazquez Joaquin Carballido Cecilia Fernandez Gregorio Rodriguez-Boto Mercedes Ovejero 《Cytotherapy》2018,20(6):806-819
Background aims
Cell therapy with autologous mesenchymal stromal cells (MSCs) in patients with spinal cord injury (SCI) is beginning, and the search for its better clinical application is an urgent need.Methods
We present a phase 2 clinical trial in patients with chronic SCI who received three intrathecal administrations of 100 x 106 MSCs and were followed for 10 months from the first administration. Efficacy analysis was performed on nine patients, and safety analysis was performed on 11 patients. Clinical scales, urodynamic, neurophysiological and neuroimaging studies were performed previous to treatment and at the end of the follow-up.Results
The treatment was well-tolerated, without any adverse event related to MSC administration. Patients showed variable clinical improvement in sensitivity, motor power, spasms, spasticity, neuropathic pain, sexual function or sphincter dysfunction, regardless of the level or degree of injury, age or time elapsed from the SCI. In the course of follow-up three patients, initially classified as ASIA A, B and C, changed to ASIA B, C and D, respectively. In urodynamic studies, at the end of follow-up, 66.6% of the patients showed decrease in postmicturition residue and improvement in bladder compliance. At this time, neurophysiological studies showed that 55.5% of patients improved in somatosensory or motor-evoked potentials, and that 44.4% of patients improved in voluntary muscle contraction together with infralesional active muscle reinnervation.Conclusions
The present guideline for cell therapy is safe and shows efficacy in patients with SCI, mainly in recovery of sphincter dysfunction, neuropathic pain and sensitivity. 相似文献27.
Maria Laura Aon-Bertolino Juan Ignacio Romero Pablo Galeano Mariana Holubiec Maria Sol Badorrey Gustavo Ezequiel Saraceno Eva-Maria Hanschmann Christopher Horst Lillig Francisco Capani 《Biochimica et Biophysica Acta (BBA)/General Subjects》2011
Background
The oxidoreductases of the thioredoxin (Trx) family of proteins play a major role in the cellular response to oxidative stress. Redox imbalance is a major feature of brain damage. For instance, neuronal damage and glial reaction induced by a hypoxic–ischemic episode is highly related to glutamate excitotoxicity, oxidative stress and mitochondrial dysfunction. Most animal models of hypoxia–ischemia in the central nervous system (CNS) use rats to study the mechanisms involved in neuronal cell death, however, no comprehensive study on the localization of the redox proteins in the rat CNS was available.Methods
The aim of this work was to study the distribution of the following proteins of the thioredoxin and glutathione/glutaredoxin (Grx) systems in the rat CNS by immunohistochemistry: Trx1, Trx2, TrxR1, TrxR2, Txnip, Grx1, Grx2, Grx3, Grx5, and γ-GCS, peroxiredoxin 1 (Prx1), Prx2, Prx3, Prx4, Prx5, and Prx6. We have focused on areas most sensitive to a hypoxia–ischemic insult: Cerebellum, striatum, hippocampus, spinal cord, substantia nigra, cortex and retina.Results and conclusions
Previous studies implied that these redox proteins may be distributed in most cell types and regions of the CNS. Here, we have observed several remarkable differences in both abundance and regional distribution that point to a complex interplay and crosstalk between the proteins of this family.General significance
We think that these data might be helpful to reveal new insights into the role of thiol redox pathways in the pathogenesis of hypoxia–ischemia insults and other disorders of the CNS.This article is part of a Special Issue entitled Human and Murine Redox Protein Atlases. 相似文献28.
Ramiro S. Arrieta Darío A. Lijtmaer Pablo L. Tubaro 《Biological journal of the Linnean Society. Linnean Society of London》2013,110(3):528-542
The process of speciation is a crucial aspect of evolutionary biology. In this study, we analysed the patterns of evolution of postzygotic reproductive isolation in Galliformes using information on hybridization and genetic distance among species. Four main patterns arose: (1) hybrid inviability and sterility in F1 hybrids increase as species diverge; (2) the presence of geographical overlap does not affect the evolution of postzygotic isolation; (3) the galliforms follow Haldane's rule; (4) hybrid inviability is higher in F2 than in F1 hybrids, but does not appear to be increased in the backcrosses. This study contributes to the growing evidence suggesting that the patterns of evolution of postzygotic isolation and the process of speciation are shared among avian groups (and animals in general). In particular, our results support the notion of F2 hybrid inviability as being key for the maintenance of species genetic integrity when prezygotic isolation barriers are overcome in closely related species, in which postzygotic isolation in the F1 hybrid might still not be fully developed. To the contrary, hybrids from backcrosses did not show serious inviability problems (at least not more than F1 hybrids), demonstrating that they could generate gene flow among bird species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 528–542. 相似文献
29.
Shuttle vectors useful for the genetic manipulation of several moderately halophilic bacteria have been constructed. These vectors are based on the minimal replicon of pCM1, a cryptic plasmid fromChromohalobacter marismortui,combined with the useful properties of pUC18 plasmid (i.e., small size, high copy number, multiple cloning sites,lacZfragment), as well as with the trimethoprim resistance gene as a selection marker for moderate halophiles. These vectors can be efficiently transferred by RP4-mediated conjugation fromEscherichia colito the moderate halophilesChromohalobacter marismortui, Deleya halophila, Halomonas elongata, Halomonas subglaciescola,andVolcaniella eurihalina. 相似文献
30.