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61.
62.
Michael C Madigan Ryan M McEnaney Ankur J Shukla Guiying Hong Eric E Kelley Margaret M Tarpey Mark Gladwin Brian S Zuckerbraun Edith Tzeng 《Molecular medicine (Cambridge, Mass.)》2015,21(1):313-322
Chronic, nonhealing wounds result in patient morbidity and disability. Reactive oxygen species (ROS) and nitric oxide (NO) are both required for normal wound repair, and derangements of these result in impaired healing. Xanthine oxidoreductase (XOR) has the unique capacity to produce both ROS and NO. We hypothesize that XOR contributes to normal wound healing. Cutaneous wounds were created in C57Bl6 mice. XOR was inhibited with dietary tungsten or allopurinol. Topical hydrogen peroxide (H2O2, 0.15%) or allopurinol (30 μg) was applied to wounds every other day. Wounds were monitored until closure or collected at d 5 to assess XOR expression and activity, cell proliferation and histology. The effects of XOR, nitrite, H2O2 and allopurinol on keratinocyte cell (KC) and endothelial cell (EC) behavior were assessed. We identified XOR expression and activity in the skin and wound edges as well as granulation tissue. Cultured human KCs also expressed XOR. Tungsten significantly inhibited XOR activity and impaired healing with reduced ROS production with reduced angiogenesis and KC proliferation. The expression and activity of other tungsten-sensitive enzymes were minimal in the wound tissues. Oral allopurinol did not reduce XOR activity or alter wound healing but topical allopurinol significantly reduced XOR activity and delayed healing. Topical H2O2 restored wound healing in tungsten-fed mice. In vitro, nitrite and H2O2 both stimulated KC and EC proliferation and EC migration. These studies demonstrate for the first time that XOR is abundant in wounds and participates in normal wound healing through effects on ROS production. 相似文献
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64.
Entrainment mapping of ischemic ventricular tachycardia at a site in the left ventricle where radiofrequency ablation was successful in terminating the tachycardia revealed a post-pacing interval shorter than the tachycardia cycle length. The reason for the same is explained in the current report. 相似文献
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66.
Sethy NK Singh M Kumar R Ilavazhagan G Bhargava K 《Functional & integrative genomics》2011,11(1):119-137
Exposure to high altitude (and thus hypobaric hypoxia) induces electrophysiological, metabolic, and morphological modifications
in the brain leading to several neurological clinical syndromes. Despite the known fact that hypoxia episodes in brain are
a common factor for many neuropathologies, limited information is available on the underlying cellular and molecular mechanisms.
In this study, we investigated the temporal effect of short-term (0–12 h) chronic hypobaric hypoxia on global gene expression
of rat brain followed by detailed canonical pathway analysis and regulatory network identification. Our analysis revealed
significant alteration of 33, 17, 53, 81, and 296 genes (p < 0.05, <1.5-fold) after 0.5, 1, 3, 6, and 12 h of hypoxia, respectively. Biological processes like regulation, metabolic,
and transport pathways are temporally activated along with anti- and proinflammatory signaling networks like PI3K/AKT, NF-κB,
ERK/MAPK, IL-6 and IL-8 signaling. Irrespective of exposure durations, nuclear factor (erythroid-derived 2)-like 2 (NRF2)-mediated oxidative stress response pathway and genes were detected at all time points suggesting activation of NRF2-ARE antioxidant defense system. The results were further validated by assessing the expression levels of selected genes in
temporal as well as brain regions with quantitative RT-PCR and western blot. In conclusion, our whole brain approach with
temporal monitoring of gene expression patterns during hypobaric hypoxia has resulted in (1) deciphering sequence of pathways
and signaling networks activated during onset of hypoxia, and (2) elucidation of NRF2-orchestrated antioxidant response as a major intrinsic defense mechanism. The results of this study will aid in better understanding
and management of hypoxia-induced brain pathologies. 相似文献
67.
Identification of haptoglobin and apolipoprotein A-I as biomarkers for high altitude pulmonary edema
Ahmad Y Shukla D Garg I Sharma NK Saxena S Malhotra VK Bhargava K 《Functional & integrative genomics》2011,11(3):407-417
We have investigated the plasma proteome using 2D gel electrophoresis and matrix-assisted laser desorption/ionization tandem
time of flight from patients with high altitude pulmonary edema (HAPE). A complete proteomic analysis was performed on 20
patients with HAPE and ten healthy sea level controls. In total, we have identified 25 protein spots in human plasma and found
that 14 of them showed altered changes in HAPE patients, which mainly were acute phase proteins (APPs), compliment components,
and apolipoproteins among others. Among the APPs, haptoglobin α2 chain, haptoglobin β chain, transthyretin, and plasma retinol
binding precursor showed overexpression in HAPE patients as compared to controls. To validate the result of proteomic analysis,
two proteins were selected for enzyme-linked immunosorbent assay and Western blotting analysis. Our data conclusively shows
that two proteins, haptoglobin and apolipoprotein A-I are upregulated in plasma of HAPE patients. These proteins may provide
a fast and effective control of inflammatory damage until the subsequent mechanisms can begin to operate. Taken together,
our findings further support the hypothesis that inflammatory response system is linked to the pathophysiology of HAPE. 相似文献
68.
Infrared spectroscopic imaging for histopathologic recognition 总被引:5,自引:0,他引:5
69.
A screen for mutants of budding yeast defective in meiotic gene conversion identified a novel allele of the POL3 gene. POL3 encodes the catalytic subunit of DNA polymerase delta, an essential DNA polymerase involved in genomic DNA replication. The new allele, pol3-ct, specifies a protein missing the last four amino acids. pol3-ct shows little or no defect in DNA replication, but displays a reduction in the length of meiotic gene conversion tracts and a decrease in crossing over. We propose a model in which DNA synthesis determines the length of strand exchange intermediates and influences their resolution toward crossing over. 相似文献
70.
Ecoinformatics using wireless sensor networks: An overview 总被引:1,自引:0,他引:1
Wireless sensor networks have the potential to become significant subsystems of ecological experiment. Sensor networks consist of large number of tiny sensor nodes, all of which have sensing capabilities. These networks allow coordinated signal detection, monitoring, and tracking to enable sensor nodes to simultaneously capture geographically distinct measurements. Sensor nodes do not require predetermined positioning making such networks especially useful for applications in remote, inhospitable environments. In this paper we have tried to see the various ecological experimental scenarios, and how wireless sensor networks can be used in that field. One of the most challenging bottlenecks in the usage of wireless sensor networks in large scale experiments is the energy constraint. Various routing protocols which have tried to optimize the energy usage are also studied in the paper. 相似文献