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101.
Van Ly D Burgess JK Brock TG Lee TH Black JL Oliver BG 《American journal of physiology. Lung cellular and molecular physiology》2012,303(3):L239-L250
Eicosanoids are lipid-signaling mediators released by many cells in response to various stimuli. Increasing evidence suggests that eicosanoids such as leukotrienes and prostaglandins (PGs) may directly mediate remodeling. In this study, we assessed whether these substances could alter extracellular matrix (ECM) proteins and the inflammatory profiles of primary human airway smooth muscle cells (ASM) and fibroblasts. PGE(2) decreased both fibronectin and tenascin C in fibroblasts but only fibronectin in ASM. PGD(2) decreased both fibronectin and tenascin C in both ASM and fibroblasts, whereas PGF(2α) had no effect on ECM deposition. The selective PGI(2) analog, MRE-269, decreased fibronectin but not tenascin C in both cell types. All the PGs increased IL-6 and IL-8 release in a dose-dependent manner in ASM and fibroblasts. Changes in ECM deposition and cytokine release induced by prostaglandins in both ASM and fibroblasts were independent of an effect on cell number. Neither the acute nor repeated stimulation with leukotrienes had an effect on the deposition of ECM proteins or cytokine release from ASM or fibroblasts. We concluded that, collectively, these results provide evidence that PGs may contribute to ECM remodeling to a greater extent than leukotrienes in airway cells. 相似文献
102.
Protection from type 1 diabetes by invariant NK T cells requires the activity of CD4+CD25+ regulatory T cells 总被引:2,自引:0,他引:2
Ly D Mi QS Hussain S Delovitch TL 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(6):3695-3704
Invariant NK T (iNKT) cells regulate immune responses, express NK cell markers and an invariant TCR, and recognize lipid Ags in a CD1d-restricted manner. Previously, we reported that activation of iNKT cells by alpha-galactosylceramide (alpha-GalCer) protects against type 1 diabetes (T1D) in NOD mice via an IL-4-dependent mechanism. To further investigate how iNKT cells protect from T1D, we analyzed whether iNKT cells require the presence of another subset(s) of regulatory T cells (Treg), such as CD4+ CD25+ Treg, for this protection. We found that CD4+ CD25+ T cells from NOD.CD1d(-/-) mice deficient in iNKT cell function similarly in vitro to CD4+ CD25+ T cells from wild-type NOD mice and suppress the proliferation of NOD T responder cells upon alpha-GalCer stimulation. Cotransfer of NOD diabetogenic T cells with CD4+ CD25+ Tregs from NOD mice pretreated with alpha-GalCer demonstrated that activated iNKT cells do not influence the ability of T(regs) to inhibit the transfer of T1D. In contrast, protection from T1D mediated by transfer of activated iNKT cells requires the activity of CD4+ CD25+ T cells, because splenocytes pretreated with alpha-GalCer and then inactivated by anti-CD25 of CD25+ cells did not protect from T1D. Similarly, mice inactivated of CD4+ CD25+ T cells before alpha-GalCer treatment were also not protected from T1D. Our data suggest that CD4+ CD25+ T cells retain their function during iNKT cell activation, and that the activity of CD4+ CD25+ Tregs is required for iNKT cells to transfer protection from T1D. 相似文献
103.
Kyung Dong Lee Elizabeth J. Gray Fazli Mabood Woo-Jin Jung Trevor Charles Scott R. D. Clark Anh Ly Alfred Souleimanov Xiaomin Zhou Donald Lawrence Smith 《Planta》2009,229(4):747-755
The mechanisms by which many plant growth promoting rhizobacteria (PGPR) affect plants are unknown. We recently isolated a
rhizosphere bacterium (Bacillus thuringiensis NEB17), that promotes soybean growth and screened the liquid growth medium in which it grew for plant growth stimulating
materials. We have also shown that it produces a bacteriocin (named by us as thuricin-17 and a member of the recently described
class IId bacteriocins). Here we show that application of this bacteriocin to leaves (spray) or roots (drench) directly stimulates
the growth of both a C3 dicot (soybean) and a C4 monocot (corn). This growth stimulation is similar in nature to that previously seen when plants are treated with Nod factors.
Strain NEB17 contains three copies of the gene for thuricin 17 that code for identical amino acid sequences. These two lines
of evidence suggest that the dual functions of these proteins may have constrained their evolution. This is the first report
of direct plant growth enhancement by a bacteriocin. 相似文献
104.
Upul Bandarage Brian Hare Jonathan Parsons Ly Pham Craig Marhefka Guy Bemis Qing Tang Cameron Stuver Moody Steve Rodems Sundeep Shah Chris Adams Jose Bravo Emmanuelle Charonnet Vladimir Savic Jon H. Come Jeremy Green 《Bioorganic & medicinal chemistry letters》2009,19(17):5191-5194
We report herein the design and synthesis of 4-(benzimidazol-2-yl)-1,2,5-oxadiazol-3-amine derivatives as inhibitors of p70S6 kinase. Screening hits containing the 4-(benzimidazol-2-yl)-1,2,5-oxadiazol-3-ylamine scaffold were optimized for p70S6K potency and selectivity against related kinases. Structure-based design employing an active site homology model derived from PKA led to the preparation of benzimidazole 5-substituted compounds 26 and 27 as highly potent inhibitors (Ki <1 nM) of p70S6K, with >100-fold selectivity against PKA, ROCK and GSK3. 相似文献
105.
Maria D. Van Kerkhove Sowath Ly Javier Guitian Davun Holl Sorn San Punam Mangtani Azra Ghani Sirenda Vong 《PloS one》2009,4(7)
Background
Since 2004, 21 highly pathogenic avian influenza H5N1 outbreaks in domestic poultry and eight human cases have been confirmed in Cambodia. As a result, a large number of avian influenza education campaigns have been ongoing in provinces in which H5N1outbreaks have occurred in humans and/or domestic poultry.Methodology/Principal Findings
Data were collected from 1,252 adults >15 years old living in two southern provinces in Cambodia where H5N1 has been confirmed in domestic poultry and human populations using two cross-sectional surveys conducted in January 2006 and in November/December 2007. Poultry handling behaviors, poultry mortality occurrence and self-reported notification of suspect H5N1 poultry cases to animal health officials in these two surveys were evaluated. Our results demonstrate that although some at risk practices have declined since the first study, risky contact with poultry is still frequent. Improved rates of reporting poultry mortality were observed overall, but reporting to trained village animal health workers decreased by approximately 50%.Conclusions/Significance
Although some improvements in human behavior have occurred, there are still areas—particularly with respect to the handling of poultry among children and the proper treatment of poultry and the surrounding household environment—that need to be addressed in public health campaigns. Though there were some differences in the sampling methods of the 2006 and 2007 surveys, our results illustrate the potential to induce considerable, potentially very relevant, behavioral changes over a short period of time. 相似文献106.
107.
108.
Paul J. Converse Kathleen D. Eisenach Sue A. Theus Eric L. Nuermberger Sandeep Tyagi Lan H. Ly Deborah E. Geiman Haidan Guo Scott T. Nolan Nicole C. Akar Lee G. Klinkenberg Radhika Gupta Shichun Lun Petros C. Karakousis Gyanu Lamichhane David N. McMurray Jacques H. Grosset William R. Bishai 《PloS one》2010,5(4)
Background
It has been hypothesized that the virulence of lab-passaged Mycobacterium tuberculosis and recombinant M. tuberculosis mutants might be reduced due to multiple in vitro passages, and that virulence might be augmented by passage of these strains through mice before quantitative virulence testing in the mouse or guinea pig aerosol models.Methodology/Principal Findings
By testing three M. tuberculosis H37Rv samples, one deletion mutant, and one recent clinical isolate for survival by the quantitative organ CFU counting method in mouse or guinea pig aerosol or intravenous infection models, we could discern no increase in bacterial fitness as a result of passaging of M. tuberculosis strains in mice prior to quantitative virulence testing in two animal models. Surface lipid expression as assessed by neutral red staining and thin-layer chromatography for PDIM analysis also failed to identify virulence correlates.Conclusions/Significance
These results indicate that animal passaging of M. tuberculosis strains prior to quantitative virulence testing in mouse or guinea pig models does not enhance or restore potency to strains that may have lost virulence due to in vitro passaging. It is critical to verify virulence of parental strains before genetic manipulations are undertaken and comparisons are made. 相似文献109.
Anthony M. Oliva Ernesto Salcedo Jennifer L. Hellier Xuan Ly Kanthaiah Koka Daniel J. Tollin Diego Restrepo 《PloS one》2010,5(6)
In this report we demonstrate that differences in cage type brought unexpected effects on aggressive behavior and neuroanatomical features of the mouse olfactory bulb. A careful characterization of two cage types, including a comparison of the auditory and temperature environments, coupled with a demonstration that naris occlusion abolishes the neuroanatomical changes, lead us to conclude that a likely important factor mediating the phenotypic changes we find is the olfactory environment of the two cages. We infer that seemingly innocuous changes in cage environment can affect sensory input relevant to mice and elicit profound effects on neural output. Study of the neural mechanisms underlying animal behavior in the laboratory environment should be broadened to include neuroethological approaches to examine how the laboratory environment (beyond animal well-being and enrichment) influences neural systems and behavior. 相似文献
110.
Vong S Khieu V Glass O Ly S Duong V Huy R Ngan C Wichmann O Letson GW Margolis HS Buchy P 《PLoS neglected tropical diseases》2010,4(11):e903