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The sp act of galactose-1-phosphate uridyltransferase has been measured in individual regions of adult rat brain to see if site-specific differences in enzyme activity can aid in the understanding of brain abnormalities observed in well-treated galactosemic patients. The sp act in the cerebellum, brain stem, and midbrain were higher than in the cortex, hippocampus, and striatum. Activity in the cerebellum was 2-fold greater than that found in the cortex. Steady state levels of mRNA of the enzyme in the cerebellum were twice that of the cortex corresponding to the ratio of enzyme sp act in the two regions. Measurement of the kinetic parameters in tissue from the cerebellum and cortex revealed that the regional specificity in enzyme activity observed in the brain represents differences in the Vmax. Inhibition of the enzyme by uridine and uridine triphosphate was essentially the same for all regions and was not influenced by the 2-fold differences observed in the levels of enzyme. Inhibition by uridine was significantly greater than that for uridine triphosphate. 相似文献
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Ofer Gemer Benjamin Piura Shmuel Segal Ilana Yanai Inbar 《International journal of gynecological pathology》2003,22(4):398-400
Chondroid syringoma of the vulva is an extremely rare tumor. Of the previously reported cases, only one was clinically malignant. The authors describe a case of chondroid syringoma of the right labium majus from which arose a papillary adenocarcinoma. A right inguinal lymph node was replaced with metastatic adenocarcinoma. 相似文献
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Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
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Seventy-three patients with lip carcinoma were treated from 1970 to 1988 in the Otolaryngology Department of the Beilinson Medical Center. The most common histological type was squamous cell carcinoma which occurred in 68 patients; four tumours were basal cell carcinoma and one acinic cell carcinoma. Carcinoma of the lip is more frequent in males. Nevertheless, the frequency of carcinoma in females in our series was substantially higher than the average reported in the literature. Forty-nine patients were treated surgically and 24 patients were treated by irradiation. Analysis of the results among those treated by surgery and those treated by irradiation shows a difference in tumour local control which was statistically significant (p = 0.025). Surgical treatment is recommended because of the advantage of tumour margin assessment, avoidance of radiotherapy complications and rapid rehabilitation. Two rare cases of carcinoma of the lip in young patients (age under 20 years) are presented. 相似文献
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Modulating role of dopamine on anesthetic requirements 总被引:6,自引:0,他引:6
I S Segal J K Walton I Irwin L E DeLanney G A Ricaurte J W Langston M Maze 《European journal of pharmacology》1990,186(1):9-15
The influence of dopamine on halothane anesthetic requirements was determined in mice. Halothane anesthetic requirement was defined as the minimum anesthetic concentration (MAC) that prevented 50% animals from moving in response to a supramaximal stimulus. Levodopa (L-DOPA) dose-dependently decreased halothane MAC to a maximum of 49% of control; over the same dose range L-DOPA increased striatal dopamine nearly 4-fold. The MAC-reducing effect of L-DOPA was attenuated by selective antagonism of the D2 dopamine receptor with YM-09151-2 while selective blockade of the D1 dopamine receptor with SCH-23390 did not alter L-DOPA's effect on the MAC for halothane. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) decreased striatal dopamine by 82% and increased the MAC for halothane by 27%. Repletion of striatal dopamine with L-DOPA, in MPTP-treated mice, restored the MAC for halothane back to the control state. The regression line derived from the plot of halothane MAC versus striatal dopamine content shows a highly significant correlation between the two variables (r2 = 0.94). These are the first results to suggest that anesthetic requirements can be modulated directly and precisely by increasing or decreasing the content of a single neurotransmitter in the central nervous system. 相似文献
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Adequate fixation with several commonly used anterior cervical plate systems requires that the screws penetrate both the anterior and posterior cortices of the vertebral bodies. This report emphasizes the shortcomings of plain film and fluoroscopic examinations in confirming screw position through the posterior vertebral cortex in three patients with lower cervical trauma or tumor. These cases and radiographs of isolated vertebrae from the cervicothoracic region demonstrate the inadequacy of plain film/fluoroscopy for determination of the position of anterior cervical plate screws in relation to the posterior cortex. Only axial images such as those obtained with computed tomography are able to show the exact relationship of the screws to the posterior cortical curvature in C7 and T1. 相似文献