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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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The authors present the results of a transmission electron-microscopic study performed on a tissue sample obtained by an intraocular fine-needle aspiration biopsy in a case of retinoma. The ultrastructural study showed that the tumor was composed mainly of granular osmiophilic material which contained some tumor cells. These cells showed peculiar ultrastructural characteristics, which demonstrated their neural character, and appeared in different degenerative stages. Apparently, this is the first case in whom ultrastructural technique have been applied to study an intraocular tumor sample obtained by intraocular fine-needle aspiration biopsy, and the first case of retinoma studied by such a diagnostic approach.  相似文献   
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We present 5 patients with cyanotic congenital heart disease in whom a pulmonary valvuloplasty was performed as palliative therapy. The patients symptoms were hypoxemic spells, very low oxygen saturation and no weight gain. The oxygenation improved and symptoms disappeared. We believe that in properly selected patients this technique represents a good therapeutic modality.  相似文献   
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The aetiology of porphyria cutanea tarda (PCT) has not been elucidated, but the possibility of an autoimmune mechanism has been proposed. We report a case of an unknown clinical combination of PCT with autoimmune hypothyroidism, alopecia universalis and vitiligo with thyroid and parietal cell circulating antibodies. This is highly suggestive of underlying autoimmune damage in this patient.  相似文献   
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A polymerase chain reaction (PCR) assay was developed for detection of Chlamydia trachomatis DNA. One primer set was used, from the published sequence of the common C. trachomatis plasmid. Detection of amplified sequences was carried out by agarose gel electrophoresis. Analysis of 106 clinical samples tested by cell culture and PCR showed a sensitivity of 100% when PCR was compared with cell culture.  相似文献   
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