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991.
992.
Calcarine sulcal cortex possibly contributes to semantic recognition memory in early blind (EB). We assessed a recognition memory role using vibrotactile rhythms and a retrieval success paradigm involving learned "old" and "new" rhythms in EB and sighted. EB showed no activation differences in occipital cortex indicating retrieval success but replicated findings of somatosensory processing. Both groups showed retrieval success in primary somatosensory, precuneus, and orbitofrontal cortex. The S1 activity might indicate generic sensory memory processes. 相似文献
993.
994.
Influence of urbanization on riparian forest diversity and structure in the Georgia Piedmont, US 总被引:1,自引:0,他引:1
Riparian forests are increasingly threatened by urban expansion and land use change worldwide. This study examined the relationships
between landscape characteristics and woody plant diversity, structure, and composition of small order riparian corridors
along an urban-rural land use gradient in the Georgia Piedmont, US. Riparian plant diversity, structure, and composition were
related to landscape metrics and land use. Species richness was negatively associated with impervious surfaces and landscape
diversity, and positively associated with forest cover and largest forest patch index. Shannon species diversity was strongly
related to the biomass of non-native species, especially for the regeneration layer. Urban sites were characterized by high
richness of non-native and pioneer species. Developing sites were dominated by the non-native shrub, Ligustrum sinense Lour., and several native overstory trees, mainly Acer negundo L. While agricultural and managed forest sites were composed of ubiquitous species, unmanaged forest sites had a structurally
distinct midstory indicative of reduced disturbance. Urban and agricultural land uses showed decreased native stem densities
and signs of overstory tree regeneration failure. Results from this study highlight the impact of the surrounding landscape
matrix upon riparian forest plant diversity and structure. 相似文献
995.
Aaron S. Burton Rowan A. Madix Nilesh Vaidya Craig A. Riley Eric J. Hayden Andre Chepetan Carolina Díaz Arenas Brian C. Larson Niles Lehman 《Analytical biochemistry》2009,388(2):351-352
RNA and DNA oligonucleotides radiolabeled with 32P or 33P often require gel electrophoresis to remove undesired side and/or degradation products. Common ways to visualize these molecules after electrophoresis are by ultraviolet (UV) shadowing, which necessarily reduces the specific activity of the oligonucleotide, and by autoradiography using film, which is cumbersome and increases the cost of generating the radiolabeled molecule. A more cost-effective method is to physically inject the gel with a “Dip-N-Dot” solution of dye and radionuclide after electrophoresis but prior to phosphorimaging. The gel can be overlaid on its computer-generated image, allowing the labeled molecules to be visualized quickly. 相似文献
996.
997.
Leandra R. Mangieri Burton J. Mader Cailin E. Thomas Charles A. Taylor Austin M. Luker Tonia E. Tse Carrie Huisingh John J. Shacka 《PloS one》2014,9(4)
ATP6V0C is the bafilomycin A1-binding subunit of vacuolar ATPase, an enzyme complex that critically regulates vesicular acidification. We and others have shown previously that bafilomycin A1 regulates cell viability, autophagic flux and metabolism of proteins that accumulate in neurodegenerative disease. To determine the importance of ATP6V0C for autophagy-lysosome pathway function, SH-SY5Y human neuroblastoma cells differentiated to a neuronal phenotype were nucleofected with non-target or ATP6V0C siRNA and following recovery were treated with either vehicle or bafilomycin A1 (0.3–100 nM) for 48 h. ATP6V0C knockdown was validated by quantitative RT-PCR and by a significant decrease in Lysostracker Red staining. ATP6V0C knockdown significantly increased basal levels of microtubule-associated protein light chain 3-II (LC3-II), α-synuclein high molecular weight species and APP C-terminal fragments, and inhibited autophagic flux. Enhanced LC3 and LAMP-1 co-localization following knockdown suggests that autophagic flux was inhibited in part due to lysosomal degradation and not by a block in vesicular fusion. Knockdown of ATP6V0C also sensitized cells to the accumulation of autophagy substrates and a reduction in neurite length following treatment with 1 nM bafilomycin A1, a concentration that did not produce such alterations in non-target control cells. Reduced neurite length and the percentage of propidium iodide-positive dead cells were also significantly greater following treatment with 3 nM bafilomycin A1. Together these results indicate a role for ATP6V0C in maintaining constitutive and stress-induced ALP function, in particular the metabolism of substrates that accumulate in age-related neurodegenerative disease and may contribute to disease pathogenesis. 相似文献
998.
999.
Cavalier JF Burton M Dussart F Marchand C Rees JF Marchand-Brynaert J 《Bioorganic & medicinal chemistry》2001,9(4):1037-1044
A series of 5-aryl- and 3,5-bis-aryl-2-amino-1,4-pyrazine derivatives 4 and 6, and related imidazolopyrazinones 7, has been synthesized, the aryl groups of which are catechol and/or phenol substituents. These compounds, tested against human keratinocyte cells stressed by UVB irradiation, showed high antioxidative properties. One compound (6f) was more active than EGCG/ECG (green tea extract) in reducing cell mortality. 相似文献
1000.
Denise M. Barbulescu Wayne A. Burton Philip A. Salisbury 《In vitro cellular & developmental biology. Plant》2011,47(2):282-288
Recalcitrance to tissue culture is observed in some genotypes of Brassica napus. Several studies have confirmed that Pluronic F-68 has growth-promoting effects on numerous tissue types. This work investigated
the effect of the non-ionic surfactant Pluronic F-68 at four concentrations (0.1%, 0.25%, 0.5%, and 1% (w/v)) on the responsiveness of recalcitrant B. napus lines to tissue culture. Microspores from seven populations of B. napus were cultured on Nitsch and Nitsch medium with this compound. The embryos obtained were plated on solid B5 medium supplemented
with zeatin for shoot induction. Pluronic F-68 had a highly significant effect on the proportion of shoot regeneration (P < 0.05) in some of the recalcitrant populations. However, no strong dose–response effect was observed. The estimated probability
of a shoot occurring in the absence of Pluronic F-68 ranged from 0.04 to 0.31 depending on the genotype, while in the presence
of Pluronic F-68, it ranged from 0.07 to 0.53, respectively. 相似文献