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41.
F Z Yetkin W M Mueller G L Morris T L McAuliffe J L Ulmer R W Cox D L Daniels V M Haughton 《AJNR. American journal of neuroradiology》1997,18(7):1311
PURPOSETo evaluate the spatial specificity of functional MR imaging by comparing it with intraoperative electrocortical mapping.METHODSFunctional MR imaging was performed in 28 patients before awake craniotomy and intraoperative electrocortical mapping. Activation was mapped for finger movement, lip movement, tongue movement, word generation, and counting paradigms. During surgery, finger movement, lip movement, tongue movement, counting, and/or speaking were mapped. The functional images and the photographic recordings of the brain functions mapped during surgery were converted to bit maps and coregistered by a computer program. The distance between the intraoperatively mapped function site and the MR activation site for a comparable function was measured.RESULTSForty-six functions were recorded on MR images and intraoperative maps. In 100% of correlations, the intraoperative site and the MR activation site were within 20 mm; in 87% of correlations they were within 10 mm. For each paradigm, 67% or more of the intraoperative stimulation maps correlated within 10 mm of the MR activation site.CONCLUSIONSFor the tasks used in this study, the activation site on functional MR images correlated well with the site at which intraoperative stimulation identified function. 相似文献
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The effects of sustained changes in sympathetic activity, produced by intracisternal (i.c.) infusion of yohimbine or clonidine, on the formation of the intraneuronal noradrenaline metabolite, dihydroxyphenylglycol (DHPG), and on the efficiency of noradrenaline reuptake were examined in conscious rabbits. Noradrenaline spillover was estimated by radiotracer dilution analysis of i.v. infused [3H]noradrenaline. Noradrenaline reuptake was estimated from the amount of DHPG derived from recaptured neurotransmitter and the effects of desipramine-induced neuronal uptake blockade on noradrenaline clearance and plasma [3H]DHPG. The efficiency of neuronal reuptake was assessed from relationships between noradrenaline reuptake and spillover. Sustained sympathetic activation with i.c. yohimbine increased the amount of plasma DHPG that was derived from recaptured noradrenaline as well as that derived from other sources. Acute administration of desipramine decreased both components so that the decrease in plasma DHPG overestimated the amount derived from recaptured noradrenaline. Thus, estimation of the component of plasma DHPG that was derived from recaptured noradrenaline was most accurately achieved by examination of relationships between plasma noradrenaline and DHPG. Noradrenaline reuptake and spillover into plasma were decreased by i.c. infusion of clonidine and increased by i.c. infusion of yohimbine. Neither i.c. infusion of clonidine nor yohimbine altered relationships between noradrenaline reuptake and spillover indicating that the efficiency of neuronal reuptake was unaltered by sustained changes in sympathetic activity. 相似文献
46.
A total of 143 patients underwent radical prostatectomy. Surgical specimens were evaluated with respect to local extent of disease, Gleason grade of the primary and relative nuclear roundness of the surgical specimen. The probability of disease control in the total population was 88 per cent at 5 years. Only 8 per cent of the patients who had disease confined to the specimen failed compared to 14 per cent of those who demonstrated extension outside of the surgical margins. The incidence of failure increased as a function of seminal vesicle involvement. Seminal vesicle involvement was greatest among patients with a Gleason grade greater than 7. Postoperative radiation did not offer any apparent advantage in patients with positive margins. 相似文献
47.
The autopsy findings in a clinically and biochemically documented case of adult-onset acid maltase deficiency presenting with limb girdle myopathy are presented. The skeletal muscles, tongue, extraocular and smooth muscles of gut and arterioles showed a vacuolar myopathy, most severely affecting proximal skeletal muscles. Muscle spindles were severely affected in all muscles. The heart showed basophilic degeneration and a vacuolar myopathy. The visceral organs and nervous system were morphologically normal. Possible mechanisms for this differential involvement of muscles and tissues are discussed. 相似文献
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Safety, tolerance, and pharmacokinetics of atevirdine mesylate (U-87201E) in asymptomatic human immunodeficiency virus-infected patients. 下载免费PDF全文
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Emphysema of early onset associated with a complete deficiency of alpha-1-antitrypsin (null homozygotes) 总被引:6,自引:0,他引:6
We have compared lung function in 3 subjects with no alpha 1-antitrypsin (alpha 1-protease inhibitor) (null homozygotes) with subjects having the typical deficiency, PIZZ. We identified a 31-yr-old woman, presenting with severe obstructive lung disease, who had no detectable plasma alpha 1-antitrypsin, indicating homozygosity for a "null" (or PI*QO) allele of alpha 1-antitrypsin. Two of her sisters have a similar deficiency, one with an onset of symptoms at 17 yr of age. Because of the likelihood that there are a number of different PI*QO alleles, the type in this family has been named null Mattawa (QOmattawa). All 3 homozygotes have shown a marked deterioration of lung function over a 7-yr period of follow-up. In contrast, lung function tests of 6 age-matched nonsmoking subjects with alpha 1-antitrypsin deficiency, PI type ZZ, showed no abnormalities of lung function. The 15 to 20% of the normal plasma concentration of alpha 1-antitrypsin associated with the PI*Z allele appears to provide some protection to the lung in comparison with a complete deficiency state. 相似文献