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991.
Behavioral and neuroimaging studies in patients with borderline personality disorder (BPD) have associated orbitofrontal cortex (OFC) dysfunction with distinct symptom clusters such as impulsivity. It is unclear, however, whether abnormal patterns of OFC activity are also present during resting-state conditions and whether OFC dysfunction is specifically associated with impulsivity in BPD. This study tested the hypothesis that BPD patients would exhibit changes of OFC baseline perfusion and explored the relationship between regional cerebral blood flow and distinct BPD symptom clusters, such as impulsivity, dissociation tension and depressive symptoms. Using continuous arterial spin labeling magnetic resonance imaging at 3 Tesla, we investigated 16 women with BPD according to DSM-IV criteria and 16 healthy female control participants during resting-state conditions. Between-group comparisons were conducted using an analysis of variance (p?<?0.05 cluster corrected). Compared to controls, BPD patients exhibited decreased blood flow in the medial OFC, whereas increased blood flow was found in the left and right lateral OFC. Correlation analyses revealed a positive relationship between medial and lateral orbitofrontal blood flow and impulsivity scores, whereas measures of dissociation tension and depression did not exhibit a significant correlation with OFC perfusion. These data suggest that dysfunction of medial and lateral regions of the OFC could specifically mediate symptoms of impulsivity in BPD.  相似文献   
992.
For more than a decade numerous evidence has been reported on the mechanisms of toxicity of α-synuclein(αS) oligomers and aggregates in α-synucleinopathies.These species were thought to form freely in the cytoplasm but recent reports of αS multimer conformations when bound to synaptic vesicles in physiological conditions,have raised the question about where αS aggregation initiates.In this review we focus on recent literature regarding the impact on membrane binding and subcellular localization of αS toxic species to understand how regular cellular function of αS contributes to pathology.Notably αS has been reported to mainly associate with specific membranes in neurons such as those of synaptic vesicles,ER/Golgi and the mitochondria,while toxic species of αS have been shown to inhibit,among others,neurotransmission,protein trafficking and mitochondrial function.Strategies interfering with αS membrane binding have shown to improve αS-driven toxicity in worms and in mice.Thus,a selective membrane binding that would result in a specific subcellular localization could be the key to understand how aggregation and pathology evolves,pointing out to αS functions that are primarily affected before onset of irreversible damage.  相似文献   
993.
Intracranial large artery stenosis and occlusion disease has been considered to be the cause of 8–10 % of ischaemic strokes in North America, and 30–50 % of strokes and more than 50 % of transient ischaemic attacks in Chinese population. So far we do not know the real prevalence of intracranial disease (ID) and the distribution of its risk factors in European population. We aimed to determine the prevalence and risk factors of ID in a European stroke population with computed tomography angiography (CTA). A retrospective study of consecutive ischaemic patients at the Stroke Unit of Utrecht, The Netherlands, from September 2006 to August 2008 was conducted. We assessed the presence of occlusion and/or stenosis of intracranial Internal Carotid Artery (ICA) and Middle Cerebral Artery on post-contrast 30-mm reconstruction axial CTA images. We analyzed the proportion of patients with ID, and the association of ID with risk factors and stroke subtype. In 220 patients (187 with stroke, 33 with TIA; mean age was 65 years, 57.3 % were male), intracranial stenosis was found in 6.4 % (95 % CI 3.9–10.4), intracranial occlusion in 34.5 % (95 % CI 28.6–41.0), and both occlusion and stenosis in 2.3 % (95 % CI 1.0–5.2). Multivariate analysis showed that the variables independently associated with ID were: extracranial ICA atherosclerosis (OR, 24.64; 95 % CI 6.30–96.38) and stroke subtypes TACS–PACS (OR, 7.61; 95 % CI 3.31–17.49). In conclusion, prevalence of intracranial stenosis in our study may well be consistent with previous observations in European and non-European population. ID may have been an underestimated condition in ischaemic Caucasian population.  相似文献   
994.
We described a rare case in which a congenital abnormal vascular structure associated with mild hyperhomocysteinemia could have caused an ischemic stroke, with an unusual localization in the border-zone of MCA and PCA. We think that the lack of compensatory flow distribution from the right vertebral artery and the right posterior communicating artery probably determined the bilateral ischemic lesions in a patient, who possibly had hypotensive crisis.  相似文献   
995.
996.
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care.  相似文献   
997.
998.
Baboon syndrome is a combination of diffuse symmetrical erythema on the major flexural areas and V‐shaped erythema on both upper anteromedial thighs. Infectious agents have been described as possible triggers. We describe for the first time baboon syndrome in a child induced by a coinfection with Epstein‐Barr virus and cytomegalovirus.  相似文献   
999.
Raynaud's phenomenon (RP) is a vasospastic disorder characterized by recurrent self‐limited episodes of skin pallor, cyanosis, and hyperemia caused by paroxysmal spasms in the small arteries of the fingers and toes and can occur in any age group. Hands, feet, nose, ears, and nipples can be affected. The diagnosis is made clinically, assessing varying degrees of ischemia in the involved areas of skin, but this transient ischemia may also herald the onset of connective tissue disease. Investigation is recommended when RP starts in childhood to exclude an underlying autoimmune condition and close follow‐up for its development. Management of RP in children includes conservative and pharmacologic treatments.  相似文献   
1000.
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