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1.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
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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Serum levels of Epinephrine (E), norepinephrine (NE), heart rate (HR), skin conductance reaction (SCR) and skin conductance level (SCL) were measured in schizophrenic, endogenous depressed and anxiety patients as well as in normal controls. Conditions were rest, noise and a mental arithmetic (MA) task. Schizophrenic and depressed patients had an attenuated HR response to MA. Moreover, Schizophrenic patients also had higher NE base level and the highest NE secretion during noise. Anxiety and depressed patients showed significantly lower phasic electrodermal activity (SCR) throughout the whole trial, exclusively anxiety patients had significantly higher tonic electrodermal activity (SCL). These findings indicate that autonomous reactions discriminate between patient groups and controls as well as between each other.  相似文献   
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Thiopental-induced EEG beta activity was analyzed both visually and by computer in 33 patients with complex partial epilepsy. Studies were done in 16 patients with depth electrodes in limbic structures and 17 patients with scalp and sphenoidal electrodes. The percentage of drug-induced change in beta activity was quantified by computer using spectral analysis. The statistical significance of asymmetries between homologous sites in the amount of change was determined. The spatial distribution of significant asymmetries was used for localization and compared with the results of independent visual analysis of the thiopental EEG. Concordance between computer and visual evaluation occurred in 10 of 17 scalp/sphenoidal and 10 of 16 depth electrode tests. The accuracy of visual and computer localization was determined by comparing them with locus of itcal EEG onset, interictal spikes, and positron emission tomography. In scalp/sphenoidal studies, computer analysis indicating asymmetry appeared more likely to correlate with independent clinical criteria than visual analysis. In depth studies the reverse appeared to be true. Scalp/sphenoidal tests yielded positive results in 25-30% of patients whereas depth electrode tests were positive in 50-70% of patients. The results indicate that computer analysis of surface thiopental tests is an accurate and useful supplement to visual evaluation of these tests.  相似文献   
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The activity of stereoisomeric [1,2-bis(3-hydroxyphenyl)ethylenediamine] dichloroplatinum(II)-complexes (1-PtCl2,R,S; 2-PtCl2, R,R/S,S; 3-PtCl2, R,R; 4-PtCl2, S,S) on several tumor models (MDA-MB 231 breast cancer cell line; P 388 leukemia, mouse; L 1210 leukemia, mouse; L 5222 leukemia, rat; Ehrlich ascites tumor, mouse--wildtype; cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.) is described. For comparison the analogous [1,2-bis(4-hydroxyphenyl)ethylendiamine]dichloroplatinum (II)-complexes (5-PtCl2, R, S; 6-PtCl2, R,R/S,S; 7-PtCl2, R,R; 8-PtCl2, S,S) and cisplatin are used. 1-PtCl2 to 4-PtCl2 (OH in 3,3'-positions) show their maximum antitumor effect at lower doses than 5-PtCl2 to 8-PtCl2 (OH in 4,4'-positions). 2-PtCl2 and 6-PtCl2 (R,R/S,S) are more active than 1-PtCl2 and 5-PtCl2 (R,S). 4-PtCl2 and 8-PtCl2 (S,S) are superior to 3-PtCl2 and 7-PtCl2 (R,R). On the L 5222 leukemia 2-PtCl2 (R,R/S,S), 4-PtCl2 (S,S) and 8-PtCl2 (S,S) markedly surpass cisplatin. Strong effects are produced by 2-PtCl2 to 4-PtCl2 on the Ehrlich ascites tumor (wildtype, cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.). The combination of 4-PtCl2 with cisplatin results in a weakly synergistic effect.  相似文献   
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We present a case of volar luxation of the scaphotrapezial bone, in which radiographs suggested luxation of the scaphoid, but unclear relations to the other carpal bones. Computer tomographic reconstruction showed an isolated scaphotrapezial luxation. This was treated by closed reduction and a plaster cast, after which the patient regained normal function of her wrist.  相似文献   
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During the development of a silicone rubber implant for the delivery of estradiol 17-beta some batches of implants made from a certain lot of commercial estradiol inexplicably developed surface crystals of estradiol after several days of storage. An impurity profile was obtained for 28 lots of estradiol by a newly developed HPLC method. One or more impurities may have had a role in the spontaneous crystal growth on the surface of the implants, because the one lot of estradiol that initially had surface crystals on aging produced acceptable implants after multiple recrystallizations. Attempts to isolate suspected impurities for characterization were unsuccessful. During the manufacture of the implants, temperatures sufficient to melt the estradiol (mp, 173-179 degrees C) were used. It was expected that, upon implant cooling, melted impure estradiol would form a thermodynamically more active (i.e., noncrystalline) physical form. This metastable form could have migrated to the implant surface, where ambient conditions favored crystallization. Because melted estradiol of a higher purity tended to crystallize more readily, it was less likely to form a glass upon cooling. The phenomenon of surface crystallization was limited to one lot of estradiol with the highest level of impurities. Data from differential scanning calorimetry studies supported this conclusion.  相似文献   
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