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Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
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BackgroundThe aim of this study was to estimate the prevalence of dental prosthetic treatment and to investigate the demographic, social, economic and medical factors associated with the use of fixed and removable dentures in a representative sample of adults living in France.MethodsThe data were obtained from the 2002–2003 Decennial Health Survey, a cross-sectional study of a representative sample of the population living in France, which included 29,679 adults. Information was collected by interview. The variables collected were fixed denture, removable denture, age, gender, number of children, area of residence, nationality, educational attainment, family social status, employment status, annual household income per capita, supplementary insurance, chronic disease, eyesight problems/glasses, hearing problems/hearing aids. Multinomial logistic regression models were used to study the relationship between prosthetic treatment and demographic, socioeconomic and medical characteristics unadjusted, adjusted for age and adjusted for all the characteristics.ResultsThe prevalence of prosthetic treatment was 34.6% (95% confidence interval (CI): [34.1; 35.2]) for fixed prosthetic dentures and 13.8% (95% CI: [13.4; 14.2]) for removable prosthetic dentures. We showed a gradient between educational attainment and removable dentures; the odds ratio adjusted for all the variables (aOR) associated with no or primary education compared to post-secondary education was 2.56; 95% CI: [2.09; 3.13]. When annual household income per capita was low, subjects were less likely to report fixed dentures (aOR = 0.68; 95% CI: [0.62; 0.75]) than those with high annual household income per capita. Individuals without insurance less often reported fixed dentures than those with private insurance. Those reporting chronic disease were less likely to report fixed dentures (aOR = 0.87; 95% CI: [0.79; 0.95]) but more likely to report removable dentures (aOR = 1.29; 95% CI: [1.17; 1.43]) than those without chronic disease.ConclusionThis study reveals social, economic and medical inequalities in fixed and removable prosthetic treatment among adults in France.  相似文献   
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<正>随着科技的进步,医疗技术的不断提高,使得诸多影像学检查在临床疾病诊断和治疗工作中发挥了重要作用。20世纪90年代末推出了数字X线成像(digital radiography,DR)成像系统,DR数字影像具有成像质量高,成像速度快,辐射剂量小等优点通过该系统,可以直接将X线信号转换为数字信号,既缩短了拍摄时间,同时由于自带显示系统,医生可以第一时间获得有关患者病情的清晰影像资料,这对于  相似文献   
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Background: Traumatic brain injury (TBI) results in verbal recall deficits and impaired processing of emotion encoded in facial appearance, prosody and the linguistic content of messages. Emotion facilitates memory (emotional memory advantage) for non-brain injured (NBI) individuals but the impact of emotion on verbal recall for linguistically encoded stimuli in TBI has not been explored.

Aims: The purpose of this study was to determine the effects of stimulus emotional content on verbal recall of words and paragraphs in TBI compared to NBI individuals.

Methods and procedures: Six 10-item lists, each with five emotional and five neutral words, and six paragraphs (three emotional, three neutral) were counterbalanced and presented in random order to 20 individuals with TBI and 44 NBI. The number of words from lists and the number of content units from paragraphs were compared for the two groups.

Outcomes and results: The NBI participants recalled more words from the lists and content units from the paragraphs than the individuals with TBI. Both groups recalled significantly more emotional than neutral words. NBI but not TBI participants had significantly greater recall for information in paragraphs with emotional content.

Conclusions: Participants with TBI showed impaired recall of words and paragraph content. Emotion facilitated word and paragraph content recall for neurotypical individuals but emotional memory advantage was limited to words for the TBI participants.  相似文献   

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