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Spinal dysraphism is usually accompanied with lumbosacral lipoma. The neurological deficits such as lower extremities sensorimotor disturbances, bowel and bladder dysfunction are produced by tethering, compression of lipoma and direct transmission of external force on the spinal cord during growth period. 25 patients treated surgically at our hospital between May, 1985, and January, 1993, were reviewed. Surgical approach was designed for debulking the lipomatous mass, untethering and decompressing the cord, repairing the dural defect and paraspinal muscle cleft. 2-59 months (mean 37.5 mons) after operation the 2 patients whose neurological system were normal before operation remained intact. In other 23 patients, bowel function recovered in 75%, active urination restored and improved in 66.2%. Motor dysfunction and paresthesia of the lower extremities alleviated in 78.3%. A case of mild uremia returned to normal and another moderate case improved. None was deteriorated by the operative procedure except one case in which a posterior nerve root was injured.  相似文献   
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Diagnosis of the neoplastic progression in Barrett's esophagus using the histologic classification of dysplasia is frequently difficult. The tumor suppressor protein p53, when mutated, confers a promoter effect on cell growth. The purpose of this study was to evaluate the applicability of p53 as an intermediate biomarker of malignancy in Barrett's esophagus. Archival analysis of 100 biopsy specimens of Barrett's esophagus and 10 esophageal adenocarcinomas were compared with 35 chronic esophagitis biopsy specimens. Immunocytochemistry using an anti-p53 monoclonal antibody was performed and elevated immunoreactivity quantitated microscopically. Data were analyzed using a logistic regression model. Significant p53 immunoreactivity occurred as follows: chronic esophagitis (0%), Barrett's esophagus without dysplasia (10%), with low-grade dysplasia (60%), with high-grade dysplasia (100%), and adenocarcinoma (70%). All cases of Barrett's esophagus were significantly immunoreactive when compared with the chronic esophagitis cases (p = 0.001). There was an increase in p53 immunoreactivity as the histologic classification progressed toward adenocarcinoma (p = 0.001). Progression to high-grade dysplasia may be predicted based on p53 immunoreactivity. These findings suggest a role for p53 as an intermediate biomarker in Barrett's esophagus.  相似文献   
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Rats were handled for the first 20 days of life or were not disturbed. When adults, they were trained to approach and drink from a bottle containing sweetened milk and were then given an injection of lithium chloride to induce a taste aversion conditioned emotional response. Others were injected with physiological saline. Rats within each of the treatment groups were then randomly assigned to 4 surgical procedures: removal of the right or left neocortex; sham surgery; or no surgery. Postoperatively, they were tested for retention of taste aversion by presenting the sweetened milk and recording the amount consumed. The initial consummatory behavior was very low (showing retention of the aversion) and increased over time. There were no differences in the reacquisition curves of the non-handled groups which had received lithium chloride. The curves of the handled groups did differ: thos with an intact right hemisphere (left neocortical lesion) had the lowest asymptote, followed by the group with an intact left brain, while those with intact whole brains consumed the greatest amount of milk. In the groups given an injection of physiological saline, those with a left hemisphere lesion consumed less milk than the other groups, regardless of their early handling experience. The data show: (1) that the rat's brain is lateralized, with the right hemisphere being preferentially involved in conditioned emotional behavior; and (2) that handling in infancy makes the left hemisphere less suceptible to conditioned fear.  相似文献   
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BXSB mice have an approximately 40-60% incidence of neocortical ectopias in layer I of the prefrontal/motor cortex. Prior studies have found major behavioral differences between those with ectopias and their non-ectopic littermates. Some of these findings indicate that the two groups differ with respect to spatial reference and working memory. The purpose of this study was to measure reference and working memory in the same animals to test the hypothesis that the ectopics would have better reference memory but less effective working memory. The Lashley III maze has cul-de-sacs which must be eliminated, and T-choices where the animal has to decide whether to go left or right. Ectopic and non-ectopic mice were equally able to learn the maze and did not differ on cul-entry or T-choice errors. Then the maze was inverted and the animals were retested. Turning the maze upside down did not change the relative status of the blind alleys. Therefore, the reference memory knowledge from the prior week's training could be used to avoid entering the culs. However, inverting the maze caused a left-right mirror image reversal of the T-choices. Therefore, prior reference memory information would interfere with learning the new path through the maze, whereas working memory would enable the mouse to eliminate T-choice errors. Ectopic mice made less cul-entry errors and more T-choice errors than their non-ectopic littermates, as predicted.  相似文献   
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