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Anna Cleta Croce Uliana De Simone Mariapia Vairetti Andrea Ferrigno Eleonora Boncompagni Isabel Freitas Giovanni Bottiroli 《Photochemical & photobiological sciences》2008,7(9):1046-1053
Autofluorescence spectroscopy is a promising and powerful approach for an in vivo, real time characterization of liver functional properties. In this work, preliminary results on the dependence of liver autofluorescence parameters on the nutritional status are reported, with particular attention to vitamin A and lipid accumulation in liver tissue. Normally fed and 24 h starving rats were used as animal models. Histochemical and autofluorescence analysis showed that lipids and vitamin A colocalize in the liver parenchyma. Fasting condition results in a parallel increase in both lipids and vitamin A. Autofluorescence imaging and microspectrofluorometric analysis carried out on unfixed, unstained tissue sections under 366 nm excitation, evidenced differences in both spectral shape and response to continuous irradiation between liver biopsies from fed and starving rats. As to photobleaching, in particular, fitting analysis evidenced a reduction of about 85% of the signal attributable solely to vitamin A during the first 10 s of irradiation. The tissue whole emission measured in fed and starving rat livers exhibited reductions of about 35% and 52%, respectively, that are closely related to vitamin A contents. The findings open interesting perspectives for the set up of an in situ, real time diagnostic procedure for the assessment of liver lipid accumulation, exploiting the photophysical properties of vitamin A. 相似文献
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Alex J. Bartholomew Eleonora M. Lad Dingcai Cao Michael Bach Elizabeth T. Cirulli 《PloS one》2016,11(2)
Despite the large amount of variation found in the night (scotopic) vision capabilities of healthy volunteers, little effort has been made to characterize this variation and factors, genetic and non-genetic, that influence it. In the largest population of healthy observers measured for scotopic visual acuity (VA) and contrast sensitivity (CS) to date, we quantified the effect of a range of variables on visual performance. We found that young volunteers with excellent photopic vision exhibit great variation in their scotopic VA and CS, and this variation is reliable from one testing session to the next. We additionally identified that factors such as Circadian preference, iris color, astigmatism, depression, sex and education have no significant impact on scotopic visual function. We confirmed previous work showing that the amount of time spent on the vision test influences performance and that laser eye surgery results in worse scotopic vision. We also showed a significant effect of intelligence and photopic visual performance on scotopic VA and CS, but all of these variables collectively explain <30% of the variation in scotopic vision. The wide variation seen in young healthy volunteers with excellent photopic vision, the high test-retest agreement, and the vast majority of the variation in scotopic vision remaining unexplained by obvious non-genetic factors suggests a strong genetic component. Our preliminary genome-wide association study (GWAS) of 106 participants ruled out any common genetic variants of very large effect and paves the way for future, larger genetic studies of scotopic vision. 相似文献
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In an uncertain environment, probabilities are key to predicting future events and making adaptive choices. However, little is known about how humans learn such probabilities and where and how they are encoded in the brain, especially when they concern more than two outcomes. During functional magnetic resonance imaging (fMRI), young adults learned the probabilities of uncertain stimuli through repetitive sampling. Stimuli represented payoffs and participants had to predict their occurrence to maximize their earnings. Choices indicated loss and risk aversion but unbiased estimation of probabilities. BOLD response in medial prefrontal cortex and angular gyri increased linearly with the probability of the currently observed stimulus, untainted by its value. Connectivity analyses during rest and task revealed that these regions belonged to the default mode network. The activation of past outcomes in memory is evoked as a possible mechanism to explain the engagement of the default mode network in probability learning. A BOLD response relating to value was detected only at decision time, mainly in striatum. It is concluded that activity in inferior parietal and medial prefrontal cortex reflects the amount of evidence accumulated in favor of competing and uncertain outcomes. 相似文献
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Any Bernstein Amanda Mangeon Janice Almeida-Engler Gilbert Engler Marc Van Montagu Gilberto Sachetto-Martins Dulce Eleonora de Oliveira 《Plant signaling & behavior》2015,10(1)
Over the past decades, several studies indicate a correlation between the phytohormone auxin and cell division. The molecular players of this signaling pathway are now being uncovered. DNA Binding Protein1 from Arabidopsis (AtDBP1) is an auxin-inducible gene able to bind DNA non-specifically. In this work the tissue-expression pattern of this gene was investigated. Promoter-GUS analysis demonstrated that the AtDBP1 promoter is active in regions exhibiting intense cell division such as meristems and nematode feeding sites. Also, the promoter expression was modulated upon incubation with cell cycle blockers, indicating a potential role in cell division for this gene. Lastly, AtDBP1 antisense plants presented a higher insensitivity to auxin, and interfered negatively with auxin–induced callus formation and reduced apical dominance. 相似文献
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Francesca Scazzina Daniele Del Rio Luca Serventi Eleonora Carini Elena Vittadini 《Food biophysics》2008,3(2):235-240
Large interest has recently risen in the development of “functional” foods, products that may provide a health benefit beyond
the traditional nutrients. Foods rich in antioxidants and, simultaneously, characterized by a low glycemic index (GI), can
reduce, through a double mechanism, the risk of increased postprandial oxidative stress, which is one of the constituent of
the onset of several chronic diseases. Nutritionally enhanced tortillas were therefore developed by incorporating ingredients
with well-documented nutritional functionality (carrots, soy, and wholemeal kamut) in a standard wheat tortillas formulation,
in an attempt to create low GI and antioxidant-rich products while preserving sensory acceptability and physico-chemical properties.
Five tortilla prototypes were developed and characterized for sensory acceptability, textural attributes, color, total antioxidant
capacity, and in vivo GI. The simultaneous combination of carrot juice, soy, and wholemeal kamut resulted in a very interesting
product that was not only the most acceptable by the consumers (although slightly harder than the standard control) but also
showed the lowest GI and was relatively high in total antioxidant capacity.
This work was presented at the 2nd International Symposium on: Delivery of Functionality in Complex Food Systems, Amherst,
MA, USA, October 8–10, 2007. 相似文献