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Biomedical literature incorporates millions of figures, which are a rich and important knowledge resource for biomedical researchers. Scientists need access to the figures and the knowledge they represent in order to validate research findings and to generate new hypotheses. By themselves, these figures are nearly always incomprehensible to both humans and machines and their associated texts are therefore essential for full comprehension. The associated text of a figure, however, is scattered throughout its full-text article and contains redundant information content. In this paper, we report the continued development and evaluation of several figure summarization systems, the FigSum+ systems, that automatically identify associated texts, remove redundant information, and generate a text summary for every figure in an article. Using a set of 94 annotated figures selected from 19 different journals, we conducted an intrinsic evaluation of FigSum+. We evaluate the performance by precision, recall, F1, and ROUGE scores. The best FigSum+ system is based on an unsupervised method, achieving F1 score of 0.66 and ROUGE-1 score of 0.97. The annotated data is available at figshare.com (http://figshare.com/articles/Figure_Associated_Text_Summarization_and_Evaluation/858903). 相似文献
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Mycobacterium vanbaalenii PYR-1 is well known for its ability to degrade a wide range of high-molecular-weight (HMW) polycyclic aromatic hydrocarbons
(PAHs). The genome of this bacterium has recently been sequenced, allowing us to gain insights into the molecular basis for
the degradation of PAHs. The 6.5 Mb genome of PYR-1 contains 194 chromosomally encoded genes likely associated with degradation
of aromatic compounds. The most distinctive feature of the genome is the presence of a 150 kb major catabolic region at positions
494 ~ 643 kb (region A), with an additional 31 kb region at positions 4,711 ~ 4,741 kb (region B), which is predicted to encode
most enzymes for the degradation of PAHs. Region A has an atypical mosaic structure made of several gene clusters in which
the genes for PAH degradation are complexly arranged and scattered around the clusters. Significant differences in the gene
structure and organization as compared to other well-known aromatic hydrocarbon degraders including Pseudomonas and Burkholderia were revealed. Many identified genes were enriched with multiple paralogs showing a remarkable range of diversity, which
could contribute to the wide variety of PAHs degraded by M. vanbaalenii PYR-1. The PYR-1 genome also revealed the presence of 28 genes involved in the TCA cycle. Based on the results, we proposed
a pathway in which HMW PAHs are degraded into the β-ketoadipate pathway through protocatechuate and then mineralized to CO2 via TCA cycle. We also identified 67 and 23 genes involved in PAH degradation and TCA cycle pathways, respectively, to be
expressed as proteins. 相似文献
127.
Haywood-Watson RJ Holcomb JB Gonzalez EA Peng Z Pati S Park PW Wang W Zaske AM Menge T Kozar RA 《PloS one》2011,6(8):e23530
The early use of fresh frozen plasma as a resuscitative agent after hemorrhagic shock has been associated with improved survival, but the mechanism of protection is unknown. Hemorrhagic shock causes endothelial cell dysfunction and we hypothesized that fresh frozen plasma would restore endothelial integrity and reduce syndecan-1 shedding after hemorrhagic shock. A prospective, observational study in severely injured patients in hemorrhagic shock demonstrated significantly elevated levels of syndecan-1 (554±93 ng/ml) after injury, which decreased with resuscitation (187±36 ng/ml) but was elevated compared to normal donors (27±1 ng/ml). Three pro-inflammatory cytokines, interferon-γ, fractalkine, and interleukin-1β, negatively correlated while one anti-inflammatory cytokine, IL-10, positively correlated with shed syndecan-1. These cytokines all play an important role in maintaining endothelial integrity. An in vitro model of endothelial injury then specifically examined endothelial permeability after treatment with fresh frozen plasma orlactated Ringers. Shock or endothelial injury disrupted junctional integrity and increased permeability, which was improved with fresh frozen plasma, but not lactated Ringers. Changes in endothelial cell permeability correlated with syndecan-1 shedding. These data suggest that plasma based resuscitation preserved endothelial syndecan-1 and maintained endothelial integrity, and may help to explain the protective effects of fresh frozen plasma after hemorrhagic shock. 相似文献
128.
Tissue partitioning of cadmium in transgenic tobacco seedlings and field grown plants expressing the mouse metallothionein I gene 总被引:4,自引:0,他引:4
Ricky Yeargan Indu B. Maiti Mark T. Nielsen Arthur G. Hunt George J. Wagner 《Transgenic research》1992,1(6):261-267
Since agricultural crops contribute >70% of human cadmium (Cd) intake, modification of crops to reduce accumulation of this
pollutant metal during plant growth is desirable. Here we describe Cd accumulation characteristics of seedlings and field
grown tobacco plants expressing the Cd-chelating protein, mouse metallothionein I. The objective of the transformation is
to entrap Cd in roots as Cd-metallothionein and thereby reduce its accumulation in the shoot. Transformed and control seedlings
were exposed for 15 days in liquid culture at a field soil-solution-like Cd concentration of 0.02 μm. Transformed seedlings ofNicotiana tabacum cultivar KY 14 contained about 24% lower Cd concentration in shoots and about 5% higher Cd concentration in roots than control
seedlings. Dry weights of transformed and control tissues did not differ significantly. In the field in 1990, mature transformedN. tabacum cv. KY 14 plants exposed only to endogenous soil Cd contained about 14% lower leaf lamina Cd concentration than did controls.
Differences were significant at thep≤0.1 level in 13 of 16 leaf positions. Leaf dry weight did not differ significantly but transformed field plants had 12% fewer
leaves and were 9% shorter than the controls. Copper (Cu) concentration was significantly higher (ca10%) in the bottom nine
leaf positions of transformed plants suggesting that reduced leaf number and plant height may be due to Cu deficiency or toxicity.
Alternatively, somaclonal variation or gene position effects may be involved. No differences were found in zinc levels. WithN. tabacum cv. Petit Havana, transformed seedlings contained no less Cd in shoots but 48% higher Cd concentration in roots. However,
dry weights of shoots and roots of transformed seedlings were 25% and 26%, respectively, greater than in controls. In the
field, transformed and control plants of this cultivar showed little significant differences in leaf Cd content, plant height
or leaf number. Although comparison of additional metallothionein-expressing tobaccos and other plants is needed, results
obtained with cultivar KY 14 support the hypothesis that sequestration of Cd in roots as Cd-metallothionein may have potential
for reducing Cd content of above root tissues of certain plants. 相似文献
129.
Ricky C. K. Cheng Denis B. Tikhonov Boris S. Zhorov 《European biophysics journal : EBJ》2010,39(5):839-853
Calcium channels play crucial physiological roles. In the absence of high-resolution structures of the channels, the mechanism
of ion permeation is unknown. Here we used a method proposed in an accompanying paper (Cheng and Zhorov in Eur Biophys J,
2009) to predict possible chelation patterns of calcium ions in a structural model of the L-type calcium channel. We compared
three models in which two or three calcium ions interact with the four selectivity filter glutamates and a conserved aspartate
adjacent to the glutamate in repeat II. Monte Carlo energy minimizations yielded many complexes with calcium ions bound to
at least two selectivity filter carboxylates. In these complexes calcium-carboxylate attractions are counterbalanced by calcium-calcium
and carboxylate-carboxylate repulsions. Superposition of the complexes suggests a high degree of mobility of calcium ions
and carboxylate groups of the glutamates. We used the predicted complexes to propose a permeation mechanism that involves
single-file movement of calcium ions. The key feature of this mechanism is the presence of bridging glutamates that coordinate
two calcium ions and enable their transitions between different chelating patterns involving four to six oxygen atoms from
the channel protein. The conserved aspartate is proposed to coordinate a calcium ion incoming to the selectivity filter from
the extracellular side. Glutamates in repeats III and IV, which are most distant from the repeat II aspartate, are proposed
to coordinate the calcium ion that leaves the selectivity filter to the inner pore. Published experimental data and earlier
proposed permeation models are discussed in view of our model. 相似文献
130.
Chun-Ting Poon Cornelia Man Ricky Ngok Shun Wong Daniel W.J. Kwong Sai-Wah Tsao 《Journal of inorganic biochemistry》2010,104(1):62-10800
An amphiphilic porphyrin appended with a Ru(II)-polypyridyl complex (Ru-P) showing a moderate two-photon absorption cross-section (178.0 ± 26.8 GM), high singlet oxygen quantum yield and rapid cellular uptake was synthesized. In vitro study using human nasopharyngeal carcinoma cells showed that Ru-P exhibited a strong two-photon induced fluorescence upon uptake, lysosomal localization and potent two-photon induced cytotoxicity. These results show that Ru-P, which was designed to enhance its cellular uptake, can potentially be used as an efficacious bifunctional two-photon tumor-imaging and photodynamic therapeutic agent despite its moderate two-photon absorption cross-section. 相似文献