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991.
992.
In a 81-year-old woman, who for many years had been treated with iron and vitamin B12 injections because of a 'tendency to anaemia', congenital haemolytic anaemia on the basis of glucose-6-phosphate dehydrogenase (G6PD) deficiency was diagnosed. The iron and vitamin medication was discontinued and after a blood transfusion because of signs of heart failure, the patient could leave the hospital in good condition. After instruction with regard to provocative factors, like eating of broad beans, no more haemolytic events occurred. Of her children and grandchildren, 2 sons and 1 granddaughter were G6PD deficient.  相似文献   
993.
OBJECTIVE: To assess dynamic Gd-DTPA-enhanced magnetic resonance (MR) imaging in the diagnosis of primary breast pathology, and to test the hypothesis that analysis of contrast agent kinetics increases specificity. METHODS: Forty-seven women underwent breast MR imaging using three-dimensional and dynamic spoiled gradient-recalled sequences. Image interpretation was based on the evaluation of lesion conspicuity, signal intensity, contour and enhancement pattern from the static acquisitions. Assessment of contrast kinetics was based on pixel-by-pixel analysis of the dynamic data. A two-compartment model described by three parameters (amplitude of uptake, exchange rate and washout rate), and a three-compartment model described by two parameters (permeability and exchange rate) were used. Regions of interest were drawn for all lesions found in the dynamic sections. Mean regional pixel values were calculated for each parameter and tested for diagnostic efficacy. RESULTS: Twenty-two malignant and 36 benign lesions were examined. Fibroadenomas accounted for 86% of the benign tumours. Image interpretation had a sensitivity of 0.95 and specificity of 0.86. The fat-suppressed post-contrast images permitted good visualization of the contour and matrix characteristics of fibroadenomas, but all non-fibroadenomatous benign lesions were classified as indeterminate or suspicious. Significant differences were found between benign and malignant lesions in the amplitude of uptake (P = 0.0008) and exchange rate (P < 0.00005) of the two-compartment model, and permeability (P=0.0001) and exchange rate (P < 0.00005) of the three-compartment model. However, image interpretation was superior to the isolated use of quantitative indices (P=0.02). The most discriminating parameters were the exchange rates of both models, with no significant difference between them. CONCLUSION: Assessment of lesion morphology is essential and probably sufficient for the differentiation of fibroadenomas from malignant tumours. However, specificity of conventional MR imaging may be much lower for other types of primary benign breast pathology. Analysis of Gd-DTPA kinetics improves the specificity obtained using simple enhancement measurements and can be used to produce parametric images that provide information about lesion heterogeneity, permeability and vascularity.  相似文献   
994.
995.
The reversal of heparin by protamine may cause severe hemodynamic deterioration, characterized by systemic hypotension, pulmonary hypertension, and bronchoconstriction. A case report is presented concerning the administration of ketanserin in the treatment of pulmonary vasoconstriction and right ventricular failure following the infusion of protamine in a patient undergoing coronary artery bypass surgery and mitral valve replacement. The potential role of serotonin in the development of this serious complication is discussed.  相似文献   
996.
997.
Brain areas involved in the expression of incubation behaviour were identified in male ring dove at the onset of incubation using quantitative [14C]2-deoxyglucose (2DG) autoradiography. The uptake of 2DG in twenty-eight areas found in the hypothalamus and thalamus, and six areas in the forebrain were compared in control non-breeding and incubating birds. Although 2DG utilisation varied significantly between brain areas, significant differences between non-breeding males and incubating males were observed only in 4 of them. These were the nucleus tuberis, nucleus preopticus medialis, nucleus ovoidalis and paleostriatum primitivum. The uptake of 2DG was increased at the onset of incubation in the nucleus tuberis, nucleus preopticus medialis and nucleus ovoidalis and decrease in the paleostriatum primitivum. These findings are consistent with the hypothesis that these brain areas play a role in the initiation of incubation behaviour.  相似文献   
998.
Unreliability of numerical data causes difficulties in computer systems for decision-making, risk assessment, and similar activities. Much human judgment is non-numerical and able to make useful evaluations of alternatives under uncertainty. The Logic of Argumentation (LA) offers a basis for computerized support of decision-making in the absence of numerical data, and it is being used in a project on carcinogenic risk assessment, StAR. There are potential applications of LA in other artificial intelligence systems in chemistry, such as for synthesis planning.  相似文献   
999.
When estrogen (1 mg/mouse) was subcutaneously administered once into mice, the number of liver MNC increased but the number of thymocytes decreased profoundly from Day 3 to Day 20. Phenotypic characterization revealed that the proportion of intermediate (int) TCR cells with IL-2 receptor beta-chain (IL-2R beta) was elevated in both the liver and the thymus. Attention was then focused on how forbidden clones were distributed among various T-cell subsets, including IL-2R beta+ int TCR cells and IL-2R beta-high TCR cells. IL-2R beta+ int TCR cells are generated through the extrathymic pathway in the liver and an alternative intrathymic pathway, whereas IL-2R beta- high TCR cells are generated through the mainstream of T-cell differentiation in the thymus. It was demonstrated that forbidden clones, V beta 3+ and V beta 11+ cells, in BALB/C mice (Mls-1b2a) were confined to IL-2R beta+ int TCR cells, irrespective of the administration of estrogen. Interestingly, the proportion of forbidden clones among int TCR cells increased in the liver but decreased in the thymus after the administration of estrogen. Liver MNC that contained a high level of forbidden clones showed unexpected high levels of spontaneous proliferation and of the proliferative response to immobilized anti-V beta mAb (even in the combination of forbidden clone stimulations). The present results reveal that the levels of both int TCR cells and forbidden clones that induce hepatocyte damage preferentially increase in the liver, one of the prime target organs in autoimmune diseases, when estrogen is administered.  相似文献   
1000.
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