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231.
Clinical and morphologic observations are described in a 46 year old woman with fatal trichinosis. Attention is called to the occurrence of extensive ventricular endocardial damage with superimposed thrombosis; Evidence is presented to indicate that the most likely cause of the endocardial damage is the associated eosinophilia. The mechanism by which eosinophils damage endocardium, however, remains obscure.  相似文献   
232.
The objective was to determine the effect of hypophysectomy on the store of gonadotropin-releasing hormone (GnRH) in certain parts of the brain as revealed by immunocytochemistry. The antiserum used was prepared against synthetic GnRH conjugated with limpet hemocyanin. No change was observed in the store of GnRH in the organum vasculosum of the lamina terminalis or in the cephalic segment of the median eminence GnRH was depleted severely from the central and caudal (junction with the infundibular stem) segments of the median eminence. GnRH was not found in the axons of magnocellular neurons that regenerate during repair of the median eminence-pituitary stalk after hypophysectomy.  相似文献   
233.
Pulmonary function was studied in 117 men employed in three plants engaged in the mining and processing of perlite. Of these, 38 had been employed for ten years or more; 18 for 15 years or more and four men for 20 years or more. Review of chest films confirmed previous studies which showed no changes indicative of pneumoconiosis. Measurement of forced vital capacity (FVC) by Jones Pulmonor and by Collins 9-liter spirometer did not show reductions correlated with length of exposure, after effects of cigarette smoking had been taken into account. There was instead a slight increase in FVC associated with years in the perlite industry. The distribution of individuals with FVC below 80% of predicted also showed no association with duration of perlite exposure. Although there were slight reductions in forced expiratory volume in one second (FEV1) and in FEV1/FVC% which were associated with years in the perlite industry and which could not be explained by cigarette smoking, these reductions were not statistically significant. In summary, the population of men available for study in the major perlite-producing area of the United States, who have worked for periods up to 23 years, showed no evidence of pneumoconiosis by chest radiography or by measurement of forced vital capacity. Nevertheless, continued control of dust to ensure exposures below nuisance dust levels is essential. Medical surveillance should also continue with records being retained for periodic reevaluation.  相似文献   
234.
A mixture of sulfacetamide, sulfathiazole, and sulfabenzamide was used to develop a rapid high-pressure liquid chromatographic assay. In addition, this study provided a means to develop concepts relating solvent molar polarization parameters and retention times. A linear correlation between molar polarization and retention time was observed and will permit reasonably rapid predictions about the dependent variable.  相似文献   
235.
This article provides an overview of technology resources and services to assist persons with low vision in maintaining independent function in the home, community, and educational and vocational settings. Case studies are provided to demonstrate the integration of technology into the lives of persons with low vision.  相似文献   
236.
Narcolepsy in seven dogs   总被引:1,自引:0,他引:1  
Narcolepsy in 7 dogs was tentatively diagnosed on the onset of cataplexy, before or during young adulthood. Confirmatory polygraphic sleep recordings were done in 3 of the dogs. In 2 dogs, treatment with neostigmine did not cause the signs to disappear, thus ruling out myasthenia gravis; trials with imipramine reduced catapletic attacks. Data from case histories, polygraphic recordings, drug trials, and clinical tests were used to compare and contrast the disease in man and in the dog.  相似文献   
237.
238.
The vascular anatomy of the posterior tibial vessels has been studied in 20 legs of 10 cadavers. The number, size and distribution of the direct cutaneous and direct muscle branches of the posterior tibial vessels were recorded. For analysis, the leg was divided into four equal segments, Zone I being the most distal and Zone IV the most proximal. The direct cutaneous branches were found to cluster mainly around Zone II. The direct muscle branches to the soleus and flexor digitorum longus muscles arose chiefly in Zones II and III. Based on this knowledge, we performed fasciocutaneous, island soleus muscle, musculo-fasciocutaneous and flexor digitorum longus muscle flaps based on the posterior tibial vessels in 12 patients. Four were free fasciocutaneous flaps and eight were pedicled flaps. All flaps survived and there were no major complications. Delayed wound healing was encountered in three patients.  相似文献   
239.
PURPOSE: To determine whether high-density lipoprotein and total cholesterol levels were risk factors for increased intraocular pressure in patients with chronic open-angle glaucoma or ocular hypertension. METHODS: We measured total cholesterol, high-density lipoprotein, and total cholesterol/high-density lipoprotein ratio in 25 patients with open-angle glaucoma or ocular hypertension who had taken no glaucoma medications for four weeks. We individually matched these patients to 25 control subjects who had no history of open-angle glaucoma or ocular hypertension, on the basis of age, race, gender, and history of vascular disease or diabetes mellitus. RESULTS: We found no statistical difference in the high-density lipoprotein (P = .702) or total cholesterol (P = .177) levels or total cholesterol/high-density lipoprotein ratio between groups (P = .178, paired t test). CONCLUSION: This study indicates that increased high-density lipoprotein and total cholesterol levels are not risk factors for increased intraocular pressure.  相似文献   
240.
Mammary glands of pregnant, lactating and resting goats were studied by immunohistochemistry for lymphocyte subpopulations using a panel of monoclonal antibodies. All T lymphocyte subpopulations that may have a role in the immune response, CD2+, CD4+, CD8+ and gamma delta T cells and subsets, were present in the mammary gland and were noted to increase in number progressively during pregnancy, decrease significantly during lactation, and then moderately increase during the resting period. CD4+ cells, the predominant cell type in the mammary gland, were located mainly in the connective tissue, whereas CD2+, CD8+ and TcR1-N24+ cells were predominant in the intraepithelial areas. TcR1-N6+ cells were detected almost exclusively during pregnancy, being localized mainly in the connective tissue. Their proportion decreased markedly following parturition. Very few WC1-N3+ and -N4+ cells were detected in the mammary gland. It is suggested that the majority of gamma delta T lymphocytes in the mammary gland of the goat are CD2+ CD8+ WCl-, a distinctive subset from that of the WCl+ subset in peripheral blood.  相似文献   
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