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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
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Millicent Ford Rauch Sara Royce Hynes James Bertram y Redmond Rebecca Robinson Cicely Williams Hao Xu Joseph A. Madri Erin B. Lavik 《The European journal of neuroscience》2009,29(1):132-145
Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair. 相似文献
34.
Beatriz Luna Sara K Doll Stephen J Hegedus Nancy J Minshew John A Sweeney 《Neuropsychopharmacology》2007,61(4):474-481
BACKGROUND: Executive dysfunction has been reported at different ages in autism. It is not clear however, when this impairment emerges or how its expression is affected by development. METHODS: 61 non-mentally retarded autism participants (AUT) and 61 age, gender, and IQ matched typically developing participants (CON) were assessed with two oculomotor executive function tasks, the oculomotor delayed response task (ODR) and the antisaccade task (AS), as well as a visually-guided saccade sensorimotor task (VGS). RESULTS: The AUT group demonstrated impairments in response inhibition and spatial working memory at all ages tested. Developmental improvements in speed of sensorimotor processing and voluntary response inhibition were similar in both groups indicating sparing of some attentional control of behavior. Developmental progression in the speed of initiating a cognitive plan and maintaining information on line over time, however, was impaired in the AUT group indicating abnormal development of working memory. CONCLUSIONS: These results indicate that while executive dysfunction is present throughout development, there is evidence for both typical and atypical developmental progression of executive functions in autism. The plasticity suggested by the developmental improvements may have implications regarding appropriate developmental epochs and types of interventions aimed at enhancing cognitive capacities in individuals with autism. 相似文献
35.
Juan Francisco Sánchez Muñoz-Torrero Paloma Barquilla Raul Velasco Maria del Carmen Fernández Capitan Nazaret Pacheco Lucia Vicente Jose Luis Chicón Sara Trejo Jose Zamorano Alicia Lorenzo Hernandez 《European journal of clinical pharmacology》2010,66(12):1257-1264
Objectives
This study was designed to assess the prevalence of adverse drug reactions (ADRs) in the internal medicine wards of two teaching Hospitals, identify the most common ADRs, the principal medications involved, and determine the risk factors implicated in the occurrence of such ADRs. 相似文献36.
Sara A. Mueting Shawn L. Gerstenberger 《Bulletin of environmental contamination and toxicology》2010,84(4):497-501
The recent invasion of the Dressenid species, the quagga mussel, Dreissena bugensis, into Lakes Mead, Mohave and Havasu has raised questions about their ability to alter contaminant cycling. Mussels were collected
from 25 locations in the three lakes. The overall average was 0.036 ± 0.016 μg g−1 Hg dry wt. The range of the three lakes was from 0.014–0.093 μg g−1 Hg dry wt. There were no significant differences in mercury concentrations among the three lakes (F = 0.07; p = 0.794). From this baseline data of contaminants in quagga mussels from the lower Colorado River, this species may be used
to biomonitor lake health. 相似文献
37.
Katherine P Rankin Anli A Liu Sara Howard Hilary Slama Craig E Hou Karen Shuster Bruce L Miller 《Cognitive and behavioral neurology》2007,20(1):48-61
OBJECTIVE: To characterize dementia-induced changes in visual art production. BACKGROUND: Although case studies show altered visual artistic production in some patients with neurodegenerative disease, no case-controlled studies have quantified this phenomenon across groups of patients. METHOD: Forty-nine subjects [18 Alzheimer disease, 9 frontotemporal dementia (FTD), 9 semantic dementia (SD), 15 healthy older controls (NC)] underwent formal neuropsychologic testing of visuospatial, perceptual, and creative functioning, and produced 4 drawings. Subjective elements of drawings were rated by an expert panel that was blind to diagnosis. RESULTS: Despite equal performance on standard visuospatial tests, dementia groups produced distinct patterns of artistic features that were significantly different from NCs. FTDs used more disordered composition and less active mark-making (P<0.05). Both FTDs and SDs drawings were rated as more bizarre and demonstrated more facial distortion than NCs (P<0.05). Also, SDs drastically failed a standardized test of divergent creativity. Alzheimer disease artwork was more similar to controls than to FTDs or SDs, but showed a more muted color palette (P<0.05) and trends toward including fewer details, less ordered compositions, and occasional facial distortion. CONCLUSIONS: These group differences in artistic style likely resulted from disease-specific focal neurodegeneration, and elucidate the contributions of particular brain regions to the production of visual art. 相似文献
38.
Sara Townsend Diane Palmer & John MacFie 《Journal of human nutrition and dietetics》1997,10(3):193-195
Seven days or more of inadequate oral intake (IOI) inevitably results in a deterioration in nutritional status. Despite this well-known fact, little information is available as to the frequency with which such periods of IOI occur in clinical practice. This study results from an audit of IOI in a gastroenterological unit over a 6-month period. The results demonstrate that 17% of patients sustained significant periods of IOI of 7 days or longer. This has important implications with regard to the provision of adjuvant nutritional support. 相似文献
39.
Daniel A Waschbusch Normand J Carrey Michael T Willoughby Sara King Brendan F Andrade 《Journal of clinical child and adolescent psychology》2007,36(4):629-644
This study examined whether response to behavior modification with and without methylphenidate differed for children with attention-deficit/hyperactivity disorder (ADHD) and conduct problems (CP) depending on the presence of callous/unemotional (CU) traits. Participants were 37 children ages 7 to 12, including 19 with ADHD/CP-only and 18 with ADHD/CP-CU, referred to a university-based summer treatment program. Results showed that ADHD/CP-CU children had worse behavior in the behavior-therapy-only (BT-only) condition, especially on measures of CP, noncompliance, and rule violations, but these differences largely disappeared when medication was added to BT. Children with ADHD/CP-CU were also less likely to be normalized by treatment than were children with ADHD/CP-only. These findings, though tentative, suggest that children with ADHD/CP-CU may not show a sufficient positive response to BT alone and that the combination of medication and BT may be especially important for them. 相似文献
40.