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91.
Buzzi Maria Claudia Buzzi Marina Leporini Barbara Trujillo Amaury 《Multimedia Tools and Applications》2017,76(4):5141-5169
Multimedia Tools and Applications - We present an analysis of how visually impaired people perform gestures on touch-screen smartphones and report their preferences, explaining the procedure and... 相似文献
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Cenk Aktas Eva Dörrschuck Cathrin Schuh Marina Martinez Miró Juseok Lee Norbert Pütz Gunther Wennemuth Wolfgang Metzger Martin Oberringer Michael Veith Hashim Abdul-Khaliq 《Materials science & engineering. C, Materials for biological applications》2012,32(5):1017-1024
The effect of the micro- and nanotopography on vascular cell-surface interaction is investigated using nano- and microstructured Al2O3 as model substrate. Two different nanostructured Al2O3 surfaces composed of low density (LD) and high density (HD) nanowires (NWs) were synthesized by chemical vapour deposition (CVD) and commercially available microstructured Al2O3 plates were used for comparison. A clear diverging response of human umbilical vein endothelial cells (HUVEC) and human umbilical vein smooth muscle cells (HUVSMC) was observed on these nano- and microstructured surfaces. LD Al2O3 NWs seem to enhance the proliferation of HUVECs selectively. This selective control of the cell-surface interaction by topography may represent a key issue for the future stent material design. 相似文献
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Rafael Llobet Marina Pollán Joaquín Antón Josefa Miranda-García María Casals Inmaculada Martínez Francisco Ruiz-Perales Beatriz Pérez-Gómez Dolores Salas-Trejo Juan-Carlos Pérez-Cortés 《Computer methods and programs in biomedicine》2014
The task of breast density quantification is becoming increasingly relevant due to its association with breast cancer risk. In this work, a semi-automated and a fully automated tools to assess breast density from full-field digitized mammograms are presented. The first tool is based on a supervised interactive thresholding procedure for segmenting dense from fatty tissue and is used with a twofold goal: for assessing mammographic density (MD) in a more objective and accurate way than via visual-based methods and for labeling the mammograms that are later employed to train the fully automated tool. Although most automated methods rely on supervised approaches based on a global labeling of the mammogram, the proposed method relies on pixel-level labeling, allowing better tissue classification and density measurement on a continuous scale. The fully automated method presented combines a classification scheme based on local features and thresholding operations that improve the performance of the classifier. A dataset of 655 mammograms was used to test the concordance of both approaches in measuring MD. Three expert radiologists measured MD in each of the mammograms using the semi-automated tool (DM-Scan). It was then measured by the fully automated system and the correlation between both methods was computed. The relation between MD and breast cancer was then analyzed using a case–control dataset consisting of 230 mammograms. The Intraclass Correlation Coefficient (ICC) was used to compute reliability among raters and between techniques. The results obtained showed an average ICC = 0.922 among raters when using the semi-automated tool, whilst the average correlation between the semi-automated and automated measures was ICC = 0.838. In the case–control study, the results obtained showed Odds Ratios (OR) of 1.38 and 1.50 per 10% increase in MD when using the semi-automated and fully automated approaches respectively. It can therefore be concluded that the automated and semi-automated MD assessments present a good correlation. Both the methods also found an association between MD and breast cancer risk, which warrants the proposed tools for breast cancer risk prediction and clinical decision making. A full version of the DM-Scan is freely available. 相似文献
95.
Annalisa Marcuzzi Elisa Piscianz Marina Zweyer Roberta Bortul Claudia Loganes Martina Girardelli Gabriele Baj Lorenzo Monasta Claudio Celeghini 《International journal of molecular sciences》2016,17(3)
Deregulation of the cholesterol pathway is an anomaly observed in human diseases, many of which have in common neurological involvement and unknown pathogenesis. In this study we have used Mevalonate Kinase Deficiency (MKD) as a disease-model in order to investigate the link between the deregulation of the mevalonate pathway and the consequent neurodegeneration. The blocking of the mevalonate pathway in a neuronal cell line (Daoy), using statins or mevalonate, induced an increase in the expression of the inflammasome gene (NLRP3) and programmed cell death related to mitochondrial dysfunction. The morphology of the mitochondria changed, clearly showing the damage induced by oxidative stress and the decreased membrane potential associated with the alterations of the mitochondrial function. The co-administration of geranylgeraniol (GGOH) reduced the inflammatory marker and the damage of the mitochondria, maintaining its shape and components. Our data allow us to speculate about the mechanism by which isoprenoids are able to rescue the inflammatory marker in neuronal cells, independently from the block of the mevalonate pathway, and about the fact that cell death is mitochondria-related. 相似文献
96.
Marina Contini Simone Baccelloni Maria Teresa Frangipane Nicolò Merendino Riccardo Massantini 《Journal of Functional Foods》2012,4(1):137-146
The simultaneous consumption of different classes of phytochemical antioxidants in the diet can result in more beneficial effects than when consumed alone. In the present study, the in vitro and in vivo antioxidative effects of espresso coffee brew (EC) (rich in chlorogenic acids) with added crude hazelnut skin phenolic extract (HSPE) from hazelnut skin waste (rich in flavonoids) were studied. Both post-brewing and pre-brewing phenolic-enriched espresso coffees (PE-ECs) were analysed for total phenols and screened for their in vitro antiradical ability. Moreover, the in vivo biological effect on the antioxidant potential of plasma in rats was evaluated. The PE-ECs showed increased both in vitro and in vivo antiradical activity proportional to the added HSPE. The in vivo experiments suggested that HSPE was much more antioxidant active than the phenolic fraction naturally contained in EC. Moreover, evidence of possible synergic effects of EC and HSPE phenolics was observed in vivo. 相似文献
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Ray Lara A.; Miranda Robert Jr.; MacKillop James; McGeary John; Tidey Jennifer W.; Rohsenow Damaris J.; Gwaltney Chad; Swift Robert W.; Monti Peter M. 《Canadian Metallurgical Quarterly》2009,17(2):122
Topiramate, an anticonvulsant medication, is an efficacious treatment for alcohol dependence. To date, little is known about genetic moderators of side effects from topiramate. The objective of this study was to examine 3 single nucleotide polymorphisms (SNPs) of the glutamate receptor GluR5 gene (GRIK1) as predictors of topiramate-induced side effects in the context of a laboratory study of topiramate. Heavy drinkers (n = 51, 19 women and 32 men), 75% of whom met criteria for an alcohol use disorder, completed a 5-week dose escalation schedule to a target dose of either 200 or 300 mg or matched placebo. The combined medication groups were compared with placebo-treated individuals for side effects at target dose. Analyses revealed that an SNP in intron 9 of the GRIK1 gene (rs2832407) was associated with the severity of topiramate-induced side effects and with serum levels of topiramate. Genes underlying glutamatergic neurotransmission, such as the GRIK1 gene, may help predict heterogeneity in topiramate-induced side effects. Future studies in larger samples are needed to more fully establish these preliminary findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Igor Jerković Marina Rajić Zvonimir Marijanović Mate Bilić Stela Jokić 《分离科学与技术》2016,51(18):2925-2931
Supercritical (SC) CO2 extraction of dried Immortelle flowers was performed at different process parameters. The optimal extraction conditions related to the yield were determined by response surface methodology (yield 4.09% at 20 MPa and 52°C). The extracts were analyzed by GC-MS and tremetone derivatives dominated: bitalin A, 12-acetoxytremetone, gnaphaliol, 1-[2-(2-methyl-2,3-dihydroxypropyl)-2,3-dihydro-1-benzofuran-5-yl]ethanone, isobutyl bitalin A, and 1-[2-(acetylprop-1-en-2-yl)-3-hydroxy-2,3-dihydro-1-benzofuran-5-yl]ethanone. Striking differences were found among the essential oil and SC-CO2 extracts composition. The major oil compounds were γ-curcumene, α-pinene, β-selinene, α-selinene, and limonene. Mono- and sesquiterpene were found among minor constituents of the extracts. Neryl acetate was present in the extracts and essential oil. 相似文献