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971.
Despite standards of living and life expectancy amongst the highest in Europe, Switzerland exhibits fairly substantial social inequities in health. As regards male mortality by socio-economic group, these differentials are both marked and independent of cause of death. There is a wealth of information on morbidity and disability supporting the hypothesis that people in lower socio-economic groups tend to age faster and suffer more at younger ages. It is similarly evident that infants of low class mothers, particularly those unwed, underprivileged immigrant, are at excess risk. The Swiss results are of political and scientific interest in that they suggest that the average wealth of a community does not determine health differentials.  相似文献   
972.
973.
An 80-year-old man was evaluated for an epibulbar tumor on a phthisical eye. The initial biopsy diagnosis of the epibulbar tumor was poorly differentiated neoplasm. Exenteration of the phthisical eye and orbital contents showed an extensive pleomorphic adenocarcinoma of the nonpigmented epithelium of the ciliary body with extraocular extension. There was evidence of hyaluronic acid secretion and immunohistochemical staining was strong for vimentin, focal for epithelial membrane antigen and S-100 protein, and weak for neuron-specific-enolase. Electron microscopy demonstrated desmosomes between tumor cells, areas of thick, multilaminar basement membrane production surrounding individual tumor cells, and occasional intracytoplasmic intermediate filaments.  相似文献   
974.
975.
Sodium saccharin, at high doses in the diet, has been reported to cause hyperplasia of the forestomach (squamous portion of stomach), at the limiting ridge in F344 rats, in addition to its potential to induce proliferative effects on the urinary bladder epithelium. We have characterized this hyperplasia of the squamous epithelium of the forestomach at the limiting ridge in F344 and Sprague-Dawley rats given various doses of sodium saccharin for 4 to 95 wk. With increasing doses of sodium saccharin, the limiting ridge of the forestomach showed dose-related morphological changes: basal-cell hyperplasia, early papillary hyperplasia with basal-cell hyperplasia and papillary hyperplasia. Calcium saccharin in Prolab diet caused hyperplasia of the forestomach at the limiting ridge, similar to that caused by sodium saccharin. The severity of hyperplasia was influenced by the type of diet and by the strain of rats. AIN-76A diet without added sodium saccharin caused basal-cell hyperplasia in F344 rats, whereas Prolab, Purina and NIH-07 diets without added sodium saccharin had little or no effect on the forestomach. The effect of AIN-76A diet alone persisted through 95 wk of feeding without any evidence of tumour formation. In Sprague-Dawley rats, which appeared more sensitive to effects on the forestomach than F344 rats, Prolab 3200 and Purina diets without sodium saccharin caused basal-cell hyperplasia in more than half of the treated rats. The forestomach hyperplasia associated with AIN-76A or saccharin administration appears to be mild, limited in extent to the limiting ridge, and not associated with carcinogenesis.  相似文献   
976.
We studied the spatial frequency characteristics in the upper and lower hemiretina using pattern reversal VECPs. The subjects were 56 normal volunteers ranging in age from 14 to 69 years old. The latency of the first major positive component (P100) of VECPs was measured using checker board pattern stimuli under varying conditions of spatial frequency (112', 56', 28', 14', 7'). For the upper hemiretinal stimuli, the P100 peak latency vs spatial frequencies curve reached minimum at 56' approximately 28' and increased at both lower and higher frequencies. For the lower hemiretinal stimuli, this curve shifted towards lower frequencies. The results suggested that the spatial frequency characteristics between the upper and lower hemiretina were different.  相似文献   
977.
Despite the progress achieved in the treatment of ocular diseases, removal of the eyeball still has to be resorted to rather often. The records of 12 hospitals of Moscow over a year evidence 678 enucleations and eviscerations, 248 (39 percent) of these for oncologic diseases, 189 (29.1 percent) because of injury aftereffects, 153 (24 percent) because of glaucoma, and 58 (8 percent) because of ocular inflammations. Common enucleation was carried out in 203 of +/- 400 patients (except oncologic ones) and enucleation with implantation of biological and synthetic drafts in 197 cases, i.e. in half of the patients who needed it; this is explained by the absence of the necessary implants in hospitals. A bank of grafts should be created for centralized provision of ocular hospitals.  相似文献   
978.
Immunogold localisation of laminin in normal and exfoliative iris.   总被引:1,自引:1,他引:0       下载免费PDF全文
Immunoelectron microscopic studies of exfoliative iris tissue (seven specimens) revealed the presence of laminin in the fibrillar component of exfoliation material. The immunogold label was uniformly distributed on the exfoliation fibres. Deposition of laminin labelled exfoliation material in the dilator muscle was a noteworthy feature, as was an apparent depletion of laminin in the basement membranes of ostensibly unaffected vessels. In control iris tissue (five enucleated eyes) laminin was identified in the basement membrane round vascular contractile cells, but not beneath the endothelium.  相似文献   
979.
980.
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