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OL Lopez RP Brenner JT Becker RF Ulrich F Boller ST DeKosky 《Canadian Metallurgical Quarterly》1997,48(6):1521-1525
We examined whether either psychotic features (e.g., delusions and hallucinations) or EEG abnormalities are associated with more rapid progression of Alzheimer's disease (AD). AD patients with psychosis have exhibited more EEG abnormalities than those without psychosis, and both abnormal EEG and psychosis have been noted to be predictors of functional and cognitive decline in AD. Ninety-five probable AD patients participating in a longitudinal study of dementia had an EEG and a semistructured psychiatric interview at baseline. Using EEG spectral analysis, we classified records as normal/abnormal based on the parasagittal mean frequency. Patients with abnormal EEGs were more functionally (e.g., Blessed Rating Scale for activities of daily living) and cognitively (e.g., Mini-Mental State) impaired than patients with normal EEG. AD patients with psychosis were only more functionally impaired than patients without psychosis. A two-factor analysis showed no interaction between abnormal EEG and psychosis. In addition, using a Cox proportional hazard model adjusted for age and education, the presence of an abnormal EEG or psychotic symptom at study entry was associated with higher risk of reaching severe cognitive and functional impairment during follow-up. Neither abnormal EEG nor the presence of psychosis predicted death. These results indicate that both abnormal EEG and psychosis are independent predictors of disease progression but not of physical survival. 相似文献
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It has been shown that rabbit liver NAD-kinase is a Ca(2+)-dependent, calmodulin-regulated enzyme. Differences were found between the sensitivity of the alpha- and beta-forms of the enzyme to calmodulin. The maximal activation of the NAD-kinase alpha-form was observed at a calmodulin/NAD-kinase ratio equal to 2, that of the beta-form--at 4. Further increases in the above parameter (up to 10) had no effect on the activity of the alpha-form, whereas that of the beta-form dropped down to the initial (basal) level. 相似文献
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AR Elbers PJ Blaauw M de Vries PJ van Gulick OL Smithuis RP Gerrits MJ Tielen 《Canadian Metallurgical Quarterly》1996,18(4):127-131
The prevalence of allergy, lung function disorders, and bronchial hyperreactivity was studied in 102 Dutch veterinarians, subdivided into five professional groups (predominantly working with either swine, cattle, poultry, companion animals, or as a non-practitioner). The mean age of the participants was 43 years; 6 participants were females. Twenty-two per cent of the participants were overweight, and relatively more non-practitioners than practitioners were overweight. Approximately 23% of the vets reported complaints of prolonged fatigue. The data suggest a relationship between complaints of prolonged fatigue and a more than average number of daily working hours. Only a small proportion of vets were sensitized against several allergens. There were no significant differences in prevalence of distinct lung function disorders or bronchial hyperreactivity between professional groups. It is hypothesized that the respiratory complaints (chronic coughing, chronic phlegm production, stuffed nose, sneezing) reported by the vets predominantly working in swine and/or poultry practice could be caused by irritation and/or inflammation of the first part of the trachea-bronchial tree that has no measurable and permanent consequences for changes in lung function or increased bronchial hyperreactivity. The results of a skin test against allergens and determination of allergen-specific IgE in blood indicated that the respiratory complaints were probably not related to allergy against the panel of allergens tested. 相似文献
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This report describes a presumed choroidal granuloma with vitreous hemorrhage resembling choroidal melanoma. A healthy 31-year-old man, who had progressive vision loss in the right eye during 1 month, was found to have a yellow-white juxtapapillary choroidal mass. Fluorescein angiography demonstrated a choroidal neovascular membrane over the lesion. There was focal persistent hypofluorescence in the late phase of fluorescein angiography. The thickness of the lesion increased from 3.0 mm to 7.1 mm during 1 month. Subretinal and vitreous hemorrhage developed. The patient was suspected to have a choroidal granuloma and choroidal neovascular membrane, and was treated with oral steroids. Ten months later, the vitreous blood cleared completely with an attached retina. Control of inflammation may have a role in the treatment of idiopathic choroidal granulomas and some choroidal neovascular membranes secondary to ocular inflammation. 相似文献
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In this paper efficiency of applied fertilizers under tropical conditions is examined. Understanding of the fertilizer efficiency is particularly important for the developing countries mainly because there is need for enhancement of crop yields at a reduced cost. Many of the soil, plant and climatic factors of the tropical regions that contribute to the efficiency of the applied fertilizers have been discussed. Many of the tropical soils are acidic in nature and in these soils efficiency of applied fertilizer is relatively poor, mainly because plant roots are unable to grow and function to their fullest extent in utilizing the soils available nutrients. To enhance yield potentials there is need for understanding of interaction between crop species and soil and climatic variables. Incorporation and adoptation of a suitable application time can greatly enhance efficiency of urea form of nitrogen. Research findings in tropical soils have shown that an initial broadcast application of P and subsequent band treatment is more effective than either method of application alone. Current crop yields in tropical countries are far below the known yield potentials. Such low production potentials are attributed to the lack of suitable crop germplasms and understanding of improved agronomic practices. Intensification of research activities in fertilizer use efficiency in tropical countries is suggested.Senior author formerly was a Research Advisor to EMBRAPA/IICA/World Bank Program in Brazil. 相似文献
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A method has been developed for determining sterigmatocystin in yellow and white corn, barley, oats, rye, sorghum, brown and wild rice, and soybeans. A partition column packed with activated magnesium silicate was used for cleanup. Averaged recoveries are 104% in white corn, 114% in rye, 100% in oats, 134% in brown rice, 96% in barley, 105% in sorghum and wild rice, and 92% in soybeans. The limit of sensitivity is 50 mug/kg for any of these commodities. 相似文献
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Obese people have a higher risk of sternal wound dehiscence resulting from traction of suprasternal tissue. In such patients we recommend the use of retention sutures with extracorporeal plates to improve tissue connection and to disburden fascia and skin sutures. This augmented closure is simple and effective and, since 1996, has prevented wound healing problems in more than 50 patients with a body mass index greater than 27. 相似文献