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1.
背景与目的:由于缺乏特异性临床和影像表现,肿块型中枢神经系统原发性血管炎(primary angiitris of central nervous system,PACNS)常被误诊为胶质瘤.本文旨在探讨肿块型PACNS的诊断与鉴别诊断。方法:回顾性分析手术治疗的37例肿块型PACNS患者的临床及影像表现。结果:85.3%的患者出现局灶性神经功能减退,55.9%患者有不同程度皮层高级功能减退症状。70.6%的颅内病变累及脑皮层:73.5%患者的正常区域脑血管周围间隙增宽,其中76%出现血管强化;病变出现特征性的“C”形强化。结论:局灶性神经功能和高级功能减退、病变累及皮层和“C”形强化等特征.有助于诊断肿块型PACNS。  相似文献   
2.
Park use is associated with health, yet our understanding of park features related to their use is limited. Singapore's parks were audited for 30 micro-features, then geospatial analysis characterized micro-features scores for parks nearest to participants' homes. Adults (3,435) reported their park use and park-based physical activity. Using linear regression models, we found living near a park with higher micro-features scores was associated with more time in parks and park-based physical activity. Specific micro-features were associated with more park time (wildlife areas, water features, forested areas, unpaved trails (2–2.6 h/month, p < 0.05)) and with physical activity in parks (water features, forested areas, large playground, open green spaces (1.8–2.2 h/month, p < 0.05)). These findings could inform parks planning to support population-health.  相似文献   
3.
The foodscape (the built food environment) is considered one of the driving factors of the higher burden of obesity and chronic disease observed in low socio-economic status (SES) groups. Traditional data collection methods struggle to accurately capture actual access and exposure to the foodscape (realised foodscape). We assess the use of anonymised mobile phone location data (location data) in foodscape studies by applying them to a case study in Perth, Western Australia to test the hypothesis that lower SES groups have poorer realised foodscapes than high SES groups. Kernel density estimation was used to calculate realised foodscapes of different SES groups and home foodscape typologies, which were compared to home foodscapes of the different groups. The location data enabled us to measure realised foodscapes of multiple groups over an extended period and at the city scale. Low SES groups had poor availability of food outlets, including unhealthy outlets, in their home and realised foodscapes and may be more susceptible to a poor home foodscape because of low mobility.  相似文献   
4.
Cytoarchitectonic and neurochemical studies of the dorsal vagal complex in the caudal medulla oblongata of rats indicate the existence of distinct anatomical and functional compartments within its components. We applied morphometric methods to discern whether capillary networks differed quantitatively between subregions and zones of area postrema, nucleus tractus solitarii (NTS), and dorsal motor nucleus of the vagus nerve (DMN) of rats. Analysis of 11 subdivisions of area postrema identified both "true" (range in luminal diameter of 3-7.5 microns) and sinusoidal (luminal diameter greater than 7.5 microns) capillaries that, together, made the capillary density for most of area postrema 75% greater than that found in NTS and DMN (526/mm2 vs about 300/mm2). The rank order of true capillary density in area postrema along its rostracaudal axis was caudal greater than central greater than rostral, whereas the reverse order was true for sinusoidal capillaries. Dorsal (periventricular) and medial zones of area postrema throughout its rostrocaudal axis tended to have higher values for capillary density, volume, surface area, luminal diameter, and pericapillary space volume than lateral or ventral zones bordering NTS. Within 200 microns of obex, the ventral zone of rostral area postrema was distinct, having a relatively sparse capillary density that may indicate morphological specializations limiting blood-tissue communication in this subregion. There were no quantitative differences in capillary dimensions between DMN and three subnuclei of NTS. These studies add to extant evidence that the dorsal vagal complex is differentiated for specific functions. Area postrema, especially, has topographical diversity in its capillary organization that likely corresponds to complex roles in neuroendocrine, autonomic, and chemosensory mechanisms.  相似文献   
5.
We describe two patients with mild ventricular dilatation, shown to have cystic spaces in the midbrain, which we interpreted as greatly enlarged Virchow-Robin spaces. We discuss the pathophysiology and the possible relations to the mild hydrocephalus. Received: 1 September 1999/Accepted: 22 October 1999  相似文献   
6.
Aim To provide an original perspective on the power and status of first-line nurse managers by observing their working environment. Background The role of first-line nurse managers includes clinical, administrative and managerial components, with their responsibilities not always reflected in their level of organizational power. The business literature suggests that an appropriately resourced workspace is not merely functional, it also confers power and status. Method Twenty Australian rural nurse managers’ workspaces were observed, as part of a larger qualitative study that explored their role and organizational power using semi-structured interviews. The observational data consisted of detailed researcher notes that were analysed thematically. Results The nurse managers’ workspaces were suboptimal and did not provide sufficient physical space or resources for the participants’ to manage tasks effectively. These results were considered using Kanter’s theory of organizational power. Implications for nursing management The findings support those reported in the business literature that inadequate physical workspaces are counterproductive in terms of both functionality and organizational power. Suggestions are made regarding the workspace needs of first-line nurse managers, based on a closer alignment between the work environment and their role responsibilities. These findings have implications for decisions regarding organizational support of first-line nurse managers.  相似文献   
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8.
Enlarged perivascular spaces (EPVS), visible in brain MRI, are an important marker of small vessel disease and neuroinflammation. We systematically evaluated the literature up to June 2012 on possible methods for their computational assessment and analyzed confounds with lacunes and small white matter hyperintensities. We found six studies that assessed/identified EPVS computationally by seven different methods, and four studies that described techniques to automatically segment similar structures and are potentially suitable for EPVS segmentation. T2‐weighted MRI was the only sequence that identified all EPVS, but FLAIR and T1‐weighted images were useful in their differentiation. Inconsistency within the literature regarding their diameter and terminology, and overlap in shape, intensity, location, and size with lacunes, conspires against their differentiation and the accuracy and reproducibility of any computational segmentation technique. The most promising approach will need to combine various MR sequences and consider all these features for accurate EPVS determination. J. Magn. Reson. Imaging 2013;38:774–785. © 2013 Wiley Periodicals, Inc.  相似文献   
9.
White matter abnormalities on magnetic resonance imaging (MRI) are associated with dementia and include white matter hyperintensities (WMH; also termed leukoaraiosis) and visible perivascular spaces (PVS). We review the potential role of impaired drainage of interstitial fluid in the pathogenesis of WMH and PVS. Whereas the volume of extracellular space in the grey matter is tightly controlled, fluid accumulates and expands the extracellular spaces of the white matter in acute hydrocephalus, vasogenic edema and WMH. Although there are no conventional lymphatic vessels in the brain, there is very effective lymphatic drainage for fluid and solutes along restricted pathways in the basement membranes of cerebral capillaries and arteries in young individuals. Lymphatic drainage of the brain is impaired with age and in association with apolipoprotein E ε4, risk factors for Alzheimer's disease and cerebral amyloid angiopathy (CAA). Deposition of proteins in the lymphatic drainage pathways in the walls of cerebral arteries with age is recognized as protein elimination failure angiopathy (PEFA), as in CAA and cerebral autosomal dominant arteriopathy and leukoencephalopathy (CADASIL). Facilitating perivascular lymphatic drainage from the aging brain may play a significant role in the prevention of CAA, WMH and Alzheimer's disease and may enhance the efficacy of immunotherapy for Alzheimer's disease.  相似文献   
10.
Social network and area level characteristics have been linked to substance use. We used snowball sampling to recruit 90 predominantly African American emerging adult men who provided typical locations visited (n=510). We used generalized estimating equations to examine social network and area level predictors of substance use. Lower social network quality was associated with days of marijuana use (B=−0.0037, p<0.0001) and problem alcohol use (B=−0.0050, p=0.0181). The influence of area characteristics on substance use differed between risky and non-risky spaces. Peer and area influences are important for substance use among men, and may differ for high and low risk places.  相似文献   
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