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41.
Two cases of intracerebral pneumatocele following trauma are presented. One to two months after initial treatment both patients had deteriorating neurologic status. The diagnosis was made by radiography. When a pneumatocele is suspected clinically, computed tomography can play a vital role in determining the precise location of the gas collection, its relationship to the fracture site, and the amount of mass effect on the brain.  相似文献   
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We report a 16-month-old boy with psychomotor regression, muscle hypotonia, peripheral neuropathy, and lactic acidosis. Brain magnetic resonance imaging showed a bilateral abnormal signal in the substantia nigra and in the subthalamic nucleus, suggestive of Leigh disease. Histochemical analysis of skeletal muscle showed decreased cytochrome-c oxidase activity. Biochemical analysis of respiratory chain enzymes in muscle homogenate and in cultured fibroblasts showed isolated cytochrome-c oxidase deficiency. Western blot analysis in fibroblasts showed the absence of Surf1 protein. Genetic analysis of the SURF1 gene revealed that the patient was compound heterozygous for a previously reported mutation at the splice-junction site of intron 3 (240 + 1G > T), and for a novel 4-bp deletion in exon 6 (531_534delAAAT). Our data further enlarge the spectrum of mutations in SURF1 gene in patients with Leigh disease and cytochrome-c oxidase deficiency, contributing to better characterization of the clinical and neuroradiologic features of this group of patients for genotype-phenotype correlations.  相似文献   
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Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant role in mediatingtat induced T-cell apoptosis.  相似文献   
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BACKGROUND: Technical advances in radiation oncology provide new opportunities to study neurobehavioral outcomes of radiation therapy (RT) in children treated for brain tumors. METHODS: In this study, we describe an approach to modeling late-effects using integral biologically effective dose (IBED) combined with improved measurement of critical neuropsychological functions. RESULTS: IBED was found to provide more differentiated information about dose distribution than prescribed dose in five subjects treated for brain tumors. Furthermore, IBED was more closely related than was prescribed dose to specific changes in Attention 2-3 years post-RT. CONCLUSIONS: Results support the feasibility of this methodology as well as promising preliminary evidence of the relationship of IBED to the construct of Attention. Improved modeling could lead to more refined radiation therapy protocols that preserve critical neuropsychological functions and also provide new insights into the treatment of neurobehavioral sequelae.  相似文献   
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Acanthosis nigricans (AN) and scleredema are two skin conditions that have been reported in association with diabetes mellitus. Few cases associating scleredema and AN have been reported. A literature search did not reveal any reports of diabetic patients developing AN on top of a scleredema plaque. Here we report a patient with diabetes mellitus who developed AN within the same indurated scleredema plaque.  相似文献   
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The aim of this study was to demonstrate the equivalence of 12-Lead Electrocardiograms (EKG) obtained with the new V-Quick patch and traditional tab-style electrodes. Using a within-subject design, a convenience sample of 100 subjects with either cardiac or pulmonary disease underwent two 12-lead EKGs, one with the traditional tab-style electrodes and one with the precordial patch. Computer-generated measurements of waveform axes and amplitude were obtained for both EKGs. Comparison of mean and 95% confidence intervals revealed no significant differences in Q, R or S wave amplitude across the six precordial leads. Furthermore, a four-factor ANOVA found no significant difference (p > 0.05) in the Q, R and S wave amplitude between the type of electrode, gender and type of disease. A subset of 29 EKGs read by three experts found intra- (.90) and inter-rater (.84) reliability to be strong. In conclusion, the precordial V-Quick patch provided equivalent EKGs to those obtained using standard tab-style electrodes.  相似文献   
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