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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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This paper is a review of currently available data concerning interactions of tRNAs with the eukaryotic ribosome at various stages of translation. These data include the results obtained by means of cryo-electron microscopy and X-ray crystallography applied to various model ribosomal complexes, site-directed cross-linking with the use of tRNA derivatives bearing chemically or photochemically reactive groups in the CCA-terminal fragment and chemical probing of 28S rRNA in the region of the peptidyl transferase center. Similarities and differences in the interactions of tRNAs with prokaryotic and eukaryotic ribosomes are discussed with concomitant consideration of the extent of resemblance between molecular mechanisms of translation in eukaryotes and bacteria.  相似文献   
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The physicochemical properties of crude oil feedstock are determined by the change in its disperse structure during production, shipment, and refining to a significant degree. For this reason, it is important to determine the parameters of petroleum disperse systems (PDS) and the correlation with their macroscopic characteristics [1].  相似文献   
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The process of heat conduction through periodically contacting rods has been considered. On the basis of the method of eigenfunction expansion of the boundary-value problem an evolutionary algorithm for constructing a solution for any cycle of contacting has been proposed, an explicit solution for the first cycle has been found, and a computer program of temperature field calculation with a given accuracy from the viewpoint of the proposed mathematical model has been developed. The dependence of the total heat resistance to the thermal flow through periodically contacting metallic surfaces of two rods in the presence or absence heat resistance on the material of the contact pair, the temperature conditions, the landed forces, the geometry of the contacting surfaces, and the contact frequency and time has been established experimentally. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 81, No. 5, pp. 977–988, September–October, 2008.  相似文献   
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Based on the findings of 206 examinations, the authors advance their opinion of the role of X-ray computed tomography (XRCT) in the diagnosis of gastric cancer. The authors think that if their developed procedure for X-ray computed tomography based on the use of usual air as the only contrast agent by measuring it out in doses and administering into the gastric at CT scanning, which is called pneumoroentgenocomputered tomography (PRCT), is employed, it, preserving all the traditional, already known, advances of XRCT additionally yields highly valuable information on a direct damage to the gastric wall itself. The findings suggest that PRCT is especially effective in intramurally growing gastric cancers, the so-called squamous carcinomas, which are hardly differentiated for diagnosis and which are most common. Noteworthy is the fact that in seemingly unquestionable exophytic gastric cancer, detecting intramural tumorous infiltration adjacent to the exophyte, PRCT thus provides evidence that the exophyte revealed is the peculiar top of an iceberg, whose base shows a significant exophytic gastric carcinoma.  相似文献   
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A specific interaction of [3H]Glu with T lymphocytes from the blood of healthy donors (Kd = 0.236 microM) was revealed and described. It was found that unlabeled quisqualate, a structural analogue of L-glutamic acid, and unlabeled dipeptides Ala-Glu, Glu-Ala, and Glu-Glu competitively inhibit the specific binding of [3H]Glu to T lymphocytes (with Ki 0.19, 2.4, 3.4, and 1.2 microM, respectively). Binding experiments with conjugates of labeled and unlabeled glutamic acid with dextran showed that the receptors of [3H]Glu are localized on the outer surface of the plasma membrane of T lymphocytes.  相似文献   
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