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L Marsh MJ Morrell PK Shear EV Sullivan H Freeman A Marie KO Lim A Pfefferbaum 《Canadian Metallurgical Quarterly》1997,38(5):576-587
PURPOSE: To use quantitative magnetic resonance imaging (MRI) methods to examine the extent of volume abnormalities in the hippocampus and in extrahippocampal brain regions in localization-related epilepsy of temporal lobe origin (TLE). METHODS: Hippocampal, temporal lobe, and extratemporal lobe volumes were examined with 3-mm spin-echo coronal MRI scans in patients with unilateral TLE who were candidates for temporal lobe resection. Measures were adjusted for normal variation due to intracranial volume and age based on 72 healthy male controls. Group differences between 14 male TLE [7 left TLE (LTLE), 7 right TLE (RTLE)] patients and a subset of 49 age range-matched controls were examined with analysis of variance (ANOVA). RESULTS: As compared with controls, patients with TLE had smaller temporal lobe and frontoparietal region gray matter volumes, bilaterally, smaller temporal lobe white matter volumes bilaterally, and larger ventricular volumes. In contrast to these bilateral tissue volume deficits, hippocampal volume deficits in TLE were ipsilateral to the epileptogenic temporal lobe. CONCLUSIONS: Extrahippocampal volume abnormalities were bilateral and occurred in both temporal and extra-temporal cortical regions in TLE, whereas hippocampal deficits were related to the side of the epileptogenic focus. These data suggest that brain abnormalities in TLE are not limited to the epileptogenic region. 相似文献
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To clean the exhaust emissions as one of the most important tasks in pollution control, a study on the treatment of engine emissions with discharge assistance was reported. A DBD plasma source shaped in grid and cylinder was examined in different engine operational modes to reduce the NOX content of diesel engine exhaust. The composition of the exhaust gases and chemical reactions initiated by the discharge were analyzed. The discharge frequency had a crucial impact on the device’s performance and gas treatment. The voltages applied to the discharge gap could alter the chemical reactions occurring in the treated gases, which were indicated by the NO to NO2 ratio. The operation of the system was studied at frequencies ranging from 400 Hz to 16 kHz. 相似文献
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A Mustonen HK Ploos van Amstel R Berger MK Salo L Viinikka KO Simola 《Canadian Metallurgical Quarterly》1997,17(10):964-966
Presentation of 11 cases of retroperitoneal sarcoma. Mean time from the beginning of symptoms to diagnosis is 6 months. The primary complementary study is CT. Surgery was performed in all cases, using complete resection in 6 cases, and partial resection in 5. Ten patients relapsed. 9 of which were treated with surgical rescue, in one or more occasions; chemotherapy was added in 6 cases and radiotherapy in 7. Survival at five years is 68%, with a mean follow-up of 66 months. 相似文献