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1.
Iclea Rocha Gama Euclides Marinho Trindade-Filho Suzana Lima Oliveira Nassib Bezerra Bueno Isabelle Tenório Melo Cyro Rego Cabral-Junior Elenita M. Barros Jaqueline A. Galvão Wanessa S. Pereira Raphaela C. Ferreira Bruna R. Domingos Terezinha da Rocha Ataide 《Metabolic brain disease》2015,30(1):93-98
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Intratemporal vascular tumors: detection with CT and MR imaging 总被引:1,自引:0,他引:1
Lo WW; Shelton C; Waluch V; Solti-Bohman LG; Carberry JN; Brackmann DE; Wade CT 《Radiology》1989,171(2):445-448
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion. 相似文献
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骨巨细胞瘤的MRI诊断价值 总被引:10,自引:0,他引:10
目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料,分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号,T2WI上为不均匀高信号,Gd-DTPA增强扫描呈中度到明显强化。此外,MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息,可提高对骨巨细胞瘤诊断的准确性。 相似文献
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A López Granados M Anguita Sánchez M D Mesa Rubio M Franco Zapata R Vivancos Delgado G Bueno Ferrer J Suárez de Lezo F Vallés Belsúe 《Revista espa?ola de cardiología》1991,44(3):210-212
Almost 90% of primary acute pericarditis are idiopathic. Between specifics forms, a very low percentage of cases are due to chronic rheumatic diseases. A case of adult Still's disease (juvenile chronic rheumatoid arthritis) with acute pericarditis being the first clinical manifestation (besides fever and general syndrome) is presented. Therapy with oral prednisone was rapidly effective, and pericardial effusion resolved after 3 weeks of treatment, as echocardiography showed. 相似文献
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Agma J. M. Tbaina Afonso H. M. A. Prado Josiane M. Bueno 《Journal of medical systems》1997,21(6):353-367
This paper presents a full reconstruction process of magnetic resonance images. The first step is to bring the acquired data from the frequency domain, using a Fast Fourier Transform algorithm. A Tomographic Image Interpolation is then used to transform a sequence of tomographic slices in an isotropic volume data set, a process also called 3D Reconstruction. This work describes an automatic method whose interpolation stage is based on a previous matching stage using Delaunay Triangulation. The reconstruction approach uses an extrapolation procedure that permits appropriate treatment of the boundaries of the object under analysis. 相似文献
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The role of endogenous opiates and cholecystokinin (CCK) in the control of postprandial pyloric myoelectric activity was investigated in conscious dogs with chronically implanted intraparietal electrodes at the gastroduodenal junction. Meals consisted of either 20 g/kg of canned food (standard meal) or the same food supplemented with 0.5 mL/kg of arachis oil (fat meal). During the 6 hours after standard and fat meals, the number of pyloric spike bursts, 2-4 seconds in duration, was 61.8 +/- 15.8 and 49.9 +/- 12.7/15 minutes, respectively. Administered 15 minutes before a fat meal, naloxone (50 micrograms/kg IV) decreased the number of spike bursts by 31.4%, whereas methyl-levallorphan, a peripheral opiate antagonist, increased postprandial spike activity by 22.2% when administered IV (0.5 mg/kg) and decreased it when administered intracerobroventricularly at a dose of 10 micrograms/kg. These two antagonists administered in the same conditions before a standard meal had no effect on the postprandial spike activity. A 1-hour infusion of cholecystokinin octapeptide (CCK-8), 500 ng.kg-1.h-1 IV and 50 ng.kg-1.h-1 intracerebroventricularly, performed 1 hour after a standard meal induced a 19.6% and 15.8% decrease in the number of pyloric spike bursts, respectively. Both naloxone IV (50 micrograms/kg) and methyl-levallorphan intracerebroventricularly (10 micrograms/kg) administered before the infusion of CCK-8 reinforced this pyloric inhibition, which was antagonized by methyl-levallorphan IV (0.5 mg/kg). The CCK antagonist asperlicin, 200 micrograms/kg IV and 20 micrograms/kg intracerebroventricularly, administered before a fat meal increased pyloric spike bursts by 22.0% and 31.5%, respectively. These results indicate that after a fat meal, endogenous opiates exert a peripheral inhibitory and central stimulatory control of pyloric motility; they suggest the involvement of both peripheral and central release of CCK. 相似文献
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The role of central versus peripheral influence of dopamine (DA) in the genesis of emotional stress (ES) induced by fear to receive electric footshocks on colonic motility was evaluated in rats equipped with implanted electrodes on the proximal colon. In control rats, the frequency of colonic spike bursts increased from 7.5 +/- 1.9 to 16.0 +/- 2.1 per 10 min when the rats were placed in a test box where they had previously received electric footshocks. This increase induced by ES was significantly p less than 0.05, reduced by previous ICV or IP administration of (+)SCH 23390 (a D1 receptor antagonist) at doses of 10 and 100 micrograms/Kg, respectively. Although sulpiride (a D2 antagonist) injected ICV or IP at similar doses had no effect on the ES-induced increase in the frequency of colonic spike bursts. DA (100 micrograms/kg), and the selective D1 (SKF 38383) or D2 (quinpirole) receptor agonist injected ICV at a dose of 5 micrograms/kg also increased significantly by 48.7, 54.8, and 68.7%, respectively, the colonic spike burst frequency whereas they are inactive when injected IP at similar and higher doses. These results suggest that, in rats, (a) emotional stress stimulates colonic motility through the stimulation of dopaminergic neurons involving D1 receptors and (b) exogenous activation of central D1 and D2 receptors similarly stimulate colonic motility by increasing the occurrence of colonic spike bursts. 相似文献
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