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991.
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Daily situations involve many objects and behaviors. To comprehend the meaning of situations, the relationships between objects, behaviors, and the situational context are important. To reveal the cortical networks involved in processing these relationships we used functional magnetic resonance imaging to compare brain activation during processing of behavior–situation and object–situation relationships. Each session examined two aspects of situational relationship processing: monitoring of the situational relationship and responses to irrelevant relationships. Monitoring was analyzed by comparing cortical activation during a situational relevance judgment task with that during a physical appropriateness judgment task. Responses were analyzed by comparing neural responses to situationally irrelevant and situationally relevant components. The left medial frontal cortex, fusiform gyrus, inferior frontal gyrus, calcarine sulcus, right anterior middle temporal gyrus, orbitoinsular junction, and occipito-temporo-parietal junction were commonly activated while monitoring relationships of both types. The right anterior middle temporal gyrus and orbitoinsular junction were considered to have roles in implicit monitoring because they were more deactivated during physical judgment tasks than during the resting state; this deactivation seemed to reflect unconscious situational monitoring in the resting state. Other regions seemed to be linked to explicit conscious monitoring. Responses to irrelevance were linked to separate and category-specific cortical activation in the left medial frontal cortex and frontal pole for behavioral irrelevance and in the left orbitofrontal cortex for irrelevant objects. We demonstrated that the hierarchical structure of processing situational relationships consisted of implicit monitoring, explicit monitoring, and category-specific responses to irrelevance.  相似文献   
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A previous systematic review revealed that lutein intake leads to improved cognitive function among older adults. However, the association between lutein intake and brain health remains unclear. Methods: We searched the Web of Science, PubMed, PsycInfo, and Cochrane Library for research papers. The criteria were (1) an intervention study using oral lutein intake or a cross-sectional study that examined lutein levels and the brain, (2) participants were older adults, and (3) brain activities or structures were measured using a brain imaging technique (magnetic resonance imaging (MRI) or electroencephalography (EEG)). Results: Seven studies using MRI (brain activities during rest, cognitive tasks, and brain structure) and two studies using EEG were included. We mainly focused on MRI studies. Three intervention studies using MRI indicated that 10 mg lutein intake over 12 months had a positive impact on healthy older adults’ brain activities during learning, resting-state connectivity, and gray matter volumes. Four cross-sectional studies using MRI suggested that lutein was positively associated with brain structure and neural efficiency during cognitive tasks. Conclusion: Although only nine studies that used similar datasets were reviewed, this systematic review indicates that lutein has beneficial effects on healthy older adults’ brain health.  相似文献   
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Although it is known that health is not merely the absence of disease, the positive aspects of mental health have been less comprehensively researched compared with its negative aspects. Subjective well-being (SWB) is one of the indicators of positive psychology, and high SWB is considered to benefit individuals in multiple ways. However, the neural mechanisms underlying individual differences in SWB remain unclear, particularly in terms of brain microstructural properties as detected by diffusion tensor imaging. The present study aimed to investigate the relationship between measurements of diffusion tensor imaging [mean diffusivity (MD) and fractional anisotropy] and the degree of SWB as measured using a questionnaire. Voxel-based analysis was used to investigate the association between MD and SWB scores in healthy young adults (age, 20.7 ± 1.8 years; 695 males and 514 females). Higher levels of SWB were found to be associated with lower MD in areas surrounding the right putamen, insula, globus pallidus, thalamus and caudate. These results indicated that individual SWB is associated with variability in brain microstructural properties.  相似文献   
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A case is presented of giant renal arteriovenous malformation (AVM). A 61-year-old woman was admitted to the National Defense Medical College Hospital for further evaluation of a renal cyst. Doppler ultrasonography and magnetic resonance imaging revealed a giant renal AVM, although the patient had no history nor clinical sign suggesting an AVM. Under the diagnosis of a right renal AVM, the patient underwent AVM resection.  相似文献   
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Balloon-occluded retrograde transvenous obliteration (B-RTO) is an interventional radiologic technique that obliterates gastric fundal varices (GFV) from draining veins under balloon occlusion. Few reports have described the use of B-RTO in children. Here, we report a case of B-RTO in a 2-year-old female patient with isolated huge varices in the gastric fundus associated with portal hypertension after surgery for biliary atresia. There was no complication and thrombosis of the varices was achieved. Our results demonstrate that B-RTO is an efficacious and safe treatment for children with isolated GFV.  相似文献   
1000.
Brain MR images of a 14-month-old boy with lissencephaly and cerebellar hypoplasia showed numerous radiating linear structures in the white matter. This finding was identical to the tigroid or leopard-skin pattern that is seen in Pelizaeus-Merzbacher disease or metachromatic leukodystrophy and represents the perivascular white matter spared from demyelination. We speculate that mutations of the reelin gene, expressed both in the cortex and in the white matter, may play an important role in its development.  相似文献   
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