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Growing interest has developed in hippocampal subfield volumetry over the past few years and an increasing number of studies use the automatic segmentation algorithm implemented in FreeSurfer. However, this approach has not been validated on standard resolution T1‐weighted magnetic resonance (MR) as used in most studies. We aimed at comparing hippocampal subfield segmentation using FreeSurfer on standard T1‐weighted images versus manual delineation on dedicated high‐resolution hippocampal scans. Hippocampal subfields were segmented in 133 individuals including 98 cognitively normal controls aged 19–84 years, 17 mild cognitive impairment and 18 Alzheimer's disease (AD) patients using both methods. Intraclass correlation coefficients (ICC) and Bland–Altman plots were computed to assess the consistency between both methods, and the effects of age and diagnosis were assessed from both measures. Low to moderate ICC (0.31–0.74) were found for the subiculum and other subfields as well as for the whole hippocampus, and the correlations were very low for cornu ammonis (CA)1 (<0.1). FreeSurfer CA1 volume estimates were found to be much lower than those obtained from manual segmentation, and this bias was proportional to the volume of this structure so that no effect of age or AD could be detected on FreeSurfer CA1 volumes. This study points to the differences in the anatomic definition of the subfields between FreeSurfer and manual delineation, especially for CA1, and provides clue for improvement of this automatic technique for potential clinical application on standard T1‐weighted MR. Hum Brain Mapp 36:463–474, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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Despite the public concern about the controversial use and abuse of marijuana, the scientific community has focused on the therapeutic potentials of cannabinoid compounds and had highlighted the importance of endocannabinoids and their receptors in physiology and disease. Endocannabinoids have been shown to be important mediators in neuroendocrine and psychiatric processes such as food intake, drug reward and energy metabolism. Cannabinoid receptors are expressed by several cell lines in the liver, such as hepatocytes, myofibroblastic cells, endothelial cells and probably cholangiocytes. A perpetuating role in liver damage for the endocannabinoid system has been proposed in several steps of chronic liver disease progression. Being a major cause of death worldwide, chronic liver disease is an important problem. New therapies are needed in order to stop or slow damage progression. This review summarizes the results of experimental studies involving the endocannabinoid system in liver disease and their clinical and therapeutical implications in hepatology.  相似文献   
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Epidemiological studies have demonstrated adverse health effects of environmental pollution. Diesel exhaust (DE) is an important contributor to ambient particulate matter pollution. DE exposure has been shown to induce a pronounced inflammatory response in the airways, with an enhanced epithelial expression of IL-8, and Gro-alpha in healthy subjects. The present investigation was aimed to further characterise the epithelial response to DE in vivo, with particular reference to possible TH2 response, in non-atopic healthy subjects. To determine this response, 15 healthy, non-atopic non-smoking subjects with normal lung function were exposed to DE (PM10 300 microg/m3) and filtered air during 1 h on two separate randomised occasions. Bronchoscopy sampling of bronchial mucosal biopsies was performed 6 h after exposure. Immunohistochemical staining were performed using mAb for IL-10, IL-13 and IL-18 expression. DE exposure induced a significant increase in the expression of IL-13 in the bronchial epithelium cells, 2.1 (1.35-4.88) Md (Q1-Q3) vs. air 0.94 (0.53-1.23); P = 0.009. No significant changes were seen in IL-10 and IL-18 expression. This finding suggests an TH2-inflammatory response in the airways of non-atopic healthy individuals.  相似文献   
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This paper distinguishes between the uses of empowerment across different contexts in healthcare policy and health promotion, providing a model for the ethical and political scrutiny of those uses. We argue that the controversies currently engendered by empowerment are better understood by means of a historical distinction between two concepts of empowerment, namely, what we call the radical empowerment approach and the new wave of empowerment. Building on this distinction, we present a research agenda for ethicists and policy makers, highlighting three domains of controversy raised by the new wave of empowerment, namely: (1) the relationship between empowerment and paternalistic interferences on the part of professionals; (2) the evaluative commitment of empowerment strategies to the achievement of health‐related goals; and (3) the problems arising from the emphasis on responsibility for health in recent uses of empowerment. Finally, we encourage the explicit theorisation of these moral controversies as a necessary step for the development and implementation of ethically legitimate empowerment processes.  相似文献   
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