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GeroScience - Adjustment of cerebral blood flow (CBF) to the increased oxygen and nutrient demands of active brain regions via neurovascular coupling (NVC) has an essential role in maintenance of...  相似文献   
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The consumption of alcoholic beverages has been classified as carcinogenic to humans by the International Agency for Research on Cancer (IARC) since 1988. More recently, in 2010, ethanol as the major constituent of alcoholic beverages and its metabolite acetaldehyde were also classified as carcinogenic to humans. Alcoholic beverages as multi-component mixtures may additionally contain further known or suspected human carcinogens as constituent or contaminant. This review will discuss the occurrence and toxicology of eighteen carcinogenic compounds (acetaldehyde, acrylamide, aflatoxins, arsenic, benzene, cadmium, ethanol, ethyl carbamate, formaldehyde, furan, glyphosate, lead, 3-MCPD, 4-methylimidazole, N-nitrosodimethylamine, pulegone, ochratoxin A, safrole) occurring in alcoholic beverages as identified based on monograph reviews by the IARC. For most of the compounds of alcoholic beverages, quantitative risk assessment provided evidence for only a very low risk (such as margins of exposure above 10,000). The highest risk was found for ethanol, which may reach exposures in ranges known to increase the cancer risk even at moderate drinking (margin of exposure around 1). Other constituents that could pose a risk to the drinker were inorganic lead, arsenic, acetaldehyde, cadmium and ethyl carbamate, for most of which mitigation by good manufacturing practices is possible. Nevertheless, due to the major effect of ethanol, the cancer burden due to alcohol consumption can only be reduced by reducing alcohol consumption in general or by lowering the alcoholic strength of beverages.  相似文献   
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The aim of this study was to assess intra- and inter-observer variability of left (LA) and right atrial (RA) strain indices obtained by two-dimensional speckle-tracking echocardiography (2D-STE) in a healthy group of individuals at low-altitude and after rapid ascent to high-altitude in order to provoke altered systemic and pulmonary hemodynamics otherwise seen in various cardiac diseases. Twenty healthy subjects underwent transthoracic echocardiography during a baseline examination at low-altitude (424 m) as well as 7, 20 and 44 h after arrival at high-altitude (4559 m). Atrial strain indices (i.e. reservoir, conduit and contractile strain) were determined off-line by two independent observers. Intra- and inter-observer reproducibility of variables was assessed by intra-class correlation coefficients (ICCs), coefficients of variation and Bland Altman plots. Heart rate, systemic blood pressure and pulmonary artery pressure increased significantly from low-altitude to the first examination at high-altitude. Intra-observer ICCs were ≥0.90 except for RA conduit strain with an ICC of 0.86. The mean intra-observer differences were small and limits of agreement of relative differences were narrow for all atrial strain parameters (<3 and <16%, respectively). Inter-observer ICCs (0.80–0.90), mean biases and limits of agreement (<4 and <20%, respectively) were greater than intra-observer results for all parameters. Intra- and inter-obserer ICCs for all atrial strain variables did not differ between low- and high-altitude. 2D-STE-derived bi-atrial strain indices have excellent intra- and moderate inter-observer reproducibility with no effect of high-altitude-induced hemodynamic changes on reliability results.  相似文献   
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Neurofeedback training has been shown to influence behavior in healthy participants as well as to alleviate clinical symptoms in neurological, psychosomatic, and psychiatric patient populations. However, many real‐time fMRI neurofeedback studies report large inter‐individual differences in learning success. The factors that cause this vast variability between participants remain unknown and their identification could enhance treatment success. Thus, here we employed a meta‐analytic approach including data from 24 different neurofeedback studies with a total of 401 participants, including 140 patients, to determine whether levels of activity in target brain regions during pretraining functional localizer or no‐feedback runs (i.e., self‐regulation in the absence of neurofeedback) could predict neurofeedback learning success. We observed a slightly positive correlation between pretraining activity levels during a functional localizer run and neurofeedback learning success, but we were not able to identify common brain‐based success predictors across our diverse cohort of studies. Therefore, advances need to be made in finding robust models and measures of general neurofeedback learning, and in increasing the current study database to allow for investigating further factors that might influence neurofeedback learning.  相似文献   
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If humans are exposed prenatally to antiepileptic drugs (AEDs), cognitive impairment may be the consequence. Driven by results of experimental work showing that AEDs may induce neuronal death in the developing rodent brain, we wanted to explore whether prenatal exposure to AEDs (PAE) may result in structural changes in the human brain. For this purpose we investigated a group of healthy young adults with PAE and a group of age-matched unexposed healthy controls by magnetic resonance imaging (MRI) of the brain. Local differences in cerebral morphology associated with PAE were analysed in volumetric MRI data by use of voxelwise comparisons of grey and white matter images. Significant regional decreases of grey matter volumes were found in PAE subjects in the area of the lentiform nucleus, including both pallidum and putamen bilaterally, and the hypothalamus. No significant regional differences in white matter volumes were found. We conclude that PAE causes subtle morphological changes in grey matter of the human brain which are conform with lower cell numbers in the basal ganglia and the hypothalamus.  相似文献   
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PURPOSE: The combination of paclitaxel with carboplatin is effective in advanced-stage non-small cell lung cancer (NSCLC). This phase III study was designed to compare the efficacy and tolerability of a weekly versus an every-3-week schedule in the first-line treatment of advanced-stage NSCLC. PATIENTS AND METHODS: Chemotherapy-naive patients were randomized to receive paclitaxel 100 mg/m2 and carboplatin at an area under the curve of 2 once weekly for 6-8 weeks (arm A) or paclitaxel 200 mg/m2 and carboplatin at an area under the curve of 6 on day 1 every 21 days (arm B). RESULTS: A total of 883 patients received >or= 1 chemotherapy cycle and were included in the results. The objective response rates observed (complete response plus partial response) were 38% for arm A and 33% for arm B. Median times to progression and median survival times were 6.1 months and 8.9 months in arm A and 7.2 months and 9.5 months in arm B, respectively. There were no significant differences between treatment arms. The chemotherapy was well tolerated in both schedules. However, grade 3/4 sensory neuropathy occurred more frequently with the every-3-week schedule (9.1% vs. 4.4%), whereas grade 3/4 diarrhea occurred more frequently with the weekly schedule (4.2% vs. 1.1%). CONCLUSION: In terms of response and survival, paclitaxel/carboplatin administered once weekly is comparable with the every-3-week schedule. Toxicity differences should be considered when choosing the appropriate schedule for the individual.  相似文献   
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