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991.
Cree leukoencephalopathy is a rapidly fatal infantile autosomal recessive leukodystrophy of unknown cause observed in the native North American Cree and Chippewayan indigenous population. We found in the brain of affected individuals the typical foamy cells with the oligodendroglial phenotype described in central hypomyelination syndrome/vanishing white matter, a syndrome related to mutations in the genes encoding the five subunits of the eucaryotic translation initiation factor eIF2B. In three patients of two Cree families, we found a homozygous missense mutation resulting in a histidine substitution at arginine 195 of epsilon-eIF2B.  相似文献   
992.
The DYT1 dystonia mutation is associated with an abnormal metabolic brain network characterized by hypermetabolism of the basal ganglia, supplementary motor area, and the cerebellum. In this study, we quantified the activity of this network in carriers of other dystonia mutations to determine whether this functional abnormality is linked to genotype. The findings suggest that the DYT1 metabolic topography is not genotype specific and may be present in carriers of other dystonia mutations.  相似文献   
993.
Anti-S-100 Serum blocks long-term potentiation in the hippocampal slice   总被引:2,自引:0,他引:2  
S-100 is a calcium-binding, glial protein which has been shown to be involved in behavioral learning and memory tasks. Long-term potentiation (LTP) in the hippocampus is a long-lasting enhancement of synaptic efficacy evoked by repetitive afferent stimulation. When anti-S-100 serum is applied by pressure ejection onto the stratum radiatum of area CA1 of the hippocampal slice, the amplitude of the extracellularly recorded population spike is not affected. However, repetitive stimulation of the afferents during S-100 application failed to produce LTP. At a distant site in the same slice, LTP occurs normally. Preimmune normal rabbit serum had no effect on the development of LTP. It appears that S-100 protein is involved in the establishment of LTP.  相似文献   
994.
PROBLEM. Resolution of alcohol problems without formal treatment or participation in self-help groups.
METHODS. Qualitative study using grounded theory (N = 11).
FINDINGS. The onset of alcohol problems begins with negligible penalties. Over time, the cost-benefit ratio of drinking habits continues to rise and the risks become too great. Individuals find it necessary to change their drinking patterns by reinvesting in themselves. Assets such as the ongoing availability of information, life-management skills, and self-confidence promote the change process; cultural mores and behaviors of some healthcare providers serve as liabilities. The dividends of self-resolving alcohol problems include self-pride, mental and physical health, conscientious work performance, rewarding relationships, enhancement of creative talents, and spiritual well-being.
CONCLUSIONS. Nurses can play an important role in promoting self-resolution of alcohol problems by providing accurate information and encouraging clients to reinvest in long-standing priorities and values.  相似文献   
995.
Conduction was studied in the sacral ventral roots and ventral tail nerves of dystrophic mice (dy/dy) and phenotypically normal littermates. In myelinated ventral root fibers of normal mice, conduction velocity was uniform with internodal conduction time45 ± 5 μsec (26 °C). In ventral root fibers of dystrophic mice, conduction velocity was decreased and strikingly non-uniform; both saltatory and continuous conduction were observed in different portions of the same nerve fiber. Continuous conduction with velocity <2 m/sec (26 °C) was characteristically observed in mid-root where the axons are bare; conduction was saltatory close to the exit from the spinal canal and near the spinal cord where the axons are myelinated.Maximum conduction velocity in ventral tail nerves was21 ± 3 m/sec for dystrophic mice and31 ± 4 m/sec for littermate controls (37 °C). Internodal lengths were somewhat decreased in the dystrophic peripheral nerves but there was no significant difference in maximum fiber diameters, myelin thickness or nodal morphology between dystrophic and normal nerves.  相似文献   
996.
Emerging methodological research suggests that the World Wide Web (“Web”) is an appropriate venue for survey data collection, and a promising area for delivering behavioral intervention. However, the use of the Web for research raises concerns regarding sample validity, particularly when the Web is used for recruitment and enrollment. The purpose of this paper is to describe the challenges experienced in two different Web‐based studies in which participant misrepresentation threatened sample validity: a survey study and an online intervention study. The lessons learned from these experiences generated three types of strategies researchers can use to reduce the likelihood of participant misrepresentation for eligibility in Web‐based research. Examples of procedural/design strategies, technical/software strategies and data analytic strategies are provided along with the methodological strengths and limitations of specific strategies. The discussion includes a series of considerations to guide researchers in the selection of strategies that may be most appropriate given the aims, resources and target population of their studies. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
997.
Empirical evidence shows that care management is an effective tool for improving depression treatment in primary care patients. However, several conceptual and practical issues have not been sufficiently addressed. This article explores questions concerning the scope of care management services within the chronic illness care model; optimal ways to identify depressed patients in the primary care setting; responsibilities and desirable qualifications of depression care managers; the location and manner in which care managers interact with patients; costs of services provided by care managers; and the level of supervision by mental health specialists that is necessary to ensure quality care.  相似文献   
998.
999.
The diagnosis of juvenile spondyloarthritis (JSA) is rarely entertained in young children who present with back and leg pain. We present a case of a 6-year-old male who presented with a 3-year history of severe back and leg pain and a positive Gower’s sign, and was given a presumed diagnosis of muscular dystrophy. Presenting serologic evaluation included a mildly elevated sedimentation rate and C-reactive protein (CRP). Computed tomography of the pelvis demonstrated large erosions affecting both sacro-iliac joints. Despite the unusually young age of this patient, ankylosing spondylitis seemed the most plausible diagnosis. Following rheumatological evaluation and treatment for JSA, he showed significant clinical improvement. His disease, however, has not entirely remitted with signs of enthesitis at the Achilles tendon and knees. We present this case to illustrate that JSA could account for symptoms at an early age and not considering it could lead to multiple medical visits and diagnoses. To our knowledge, based on a search of the World literature, this would appear to be the youngest case of JSA reported with demonstrable severe sacroiliitis. Presented at the 31st Annual members Meeting of the International Skeletal Society in Malta, September 2004.  相似文献   
1000.
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