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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
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The effects of chronic alcohol consumption and withdrawal on the organization of the basal dendrites of layer III pyramidal cells of the prelimbic cortex were studied in groups of rats fed on alcohol for 6 or 18 months, and in a group fed for 12 months, then switched to water for a further 6 months (withdrawal group). Three-dimensional analysis of the dendritic arborizations showed an age-dependent increase in several dendritic parameters, but a net stability was found in the metrical parameters between alcohol-fed and respective control rats. Conversely, a dendritic impoverishment occurred in the withdrawal group. The linear density of dendritic spines remained stable in all groups studied. Together with the previously found marked loss of the neurons after alcohol consumption and withdrawal, these findings point to a decrease in the available targets for afferents and therefore to the presence of probable functional alterations as a consequence of those in the connectivity patterns of the prelimbic area occurring under these conditions.  相似文献   
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Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
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Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
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The supraoptic nuclei of both male and female 30-day-old rats rendered hypothyroid by daily subcutaneous injection of propylthiouracil were studied and the results were compared with age- and sex-matched rats fed ad libitum (control rats) and with undernourished rats. Morphometric methods were used to evaluate the volume of the supraoptic nucleus and the areal and numerical densities of its neurons. These parameters allowed us to estimate the total number of neurons of this nucleus. In addition, the mean cross-sectioned area and mean nuclear diameter of the same neurons were also evaluated. The volume of the supraoptic nucleus was reduced both in hypothyroid and undernourished animals when compared with normal controls. The areal and numerical densities of neurons from the former groups were increased and the volume density of the neuropil was reduced. As a consequence, the total number of neurons was found to be identical in all groups studied. Furthermore, the mean nuclear diameters and cross-sectioned areas of the supraoptic neurons were similar in all groups. The volumetric differences and the increased packing found were always more marked for hypothyroid than for undernourished rats. Differences were not detected between male and female groups. The present results support the view that the increased cell packing in hypothyroid animals depends upon a reduction in the neuropil of the nucleus, as has been described under similar conditions in other central nervous system areas displaying identical patterns of neurogenesis. In addition, it was found that the effects of undernourishment cannot be discriminated from those dependent on neonatal hypothyroidism.  相似文献   
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