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111.
A variety of adrenal imaging agents have been used in nuclear medicine, but no agent has been developed for magnetic resonance (MR) imaging. The authors have previously observed accumulation of aminated macromolecules in adrenal glands. They now report the synthesis of a model polymeric aminated contrast agent for enhanced MR imaging of the adrenal glands. The model agent consisted of a poly-L-lysine conjugate (molecular weight, 245 kd) that had 70% free epsilon amino groups and 30% diethylenetriaminepentaacetic acid (DTPA)-derivatized amino groups to bind indium-111 or gadolinium. One hour after intravenous administration of this compound, adrenal uptake was 10.1% +/- 0.7 of injected dose per gram of tissue. When all free epsilon amino groups of the polylysine were completely substituted with DTPA, adrenal uptake was 3.4 times lower, indicating the importance of free amino groups for adrenal uptake. MR imaging in rats showed that a dose of 0.08 mmol of gadolinium per kilogram of the agent was sufficient to enhance the signal intensity of adrenal glands. There hours after intravenous administration of the agent, signal intensity of the adrenal glands was 186% of precontrast values (liver, 165%; kidney, 91%). Fluorescence microscopy showed that the agent accumulated primarily in the cortical zona glomerulosa and in the adrenal medulla. These initial studies demonstrate the feasibility of designing contrast agents for MR imaging of the adrenal glands.  相似文献   
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The various doses of dopamine efficacy, applied for the inotropic support in 30 donors of kidneys, was investigated, as well as the preparation influence on the renal transplantation function. Inotropic support of donor using dopamine was needed in 21 donors. The occurrence rate of an acute necrosis of tubules have depended upon dopamine doses. Dopamine is the preparation of choice for the intensive therapy conduction and securing of cardiovascular stability of the donors kidneys.  相似文献   
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Studies of the factor structure of the SF-36 Health Survey are an important step in its construct validation. Its structure is also the psychometric basis for scoring physical and mental health summary scales, which are proving useful in simplifying and interpreting statistical analyses. To test the generalizability of the SF-36 factor structure, product-moment correlations among the eight SF-36 Health Survey scales were estimated for representative samples of general populations in each of 10 countries. Matrices were independently factor analyzed using identical methods to test for hypothesized physical and mental health components, and results were compared with those published for the United States. Following simple orthogonal rotation of two principal components, they were easily interpreted as dimensions of physical and mental health in all countries. These components accounted for 76% to 85% of the reliable variance in scale scores across nine European countries, in comparison with 82% in the United States. Similar patterns of correlations between the eight scales and the components were observed across all countries and across age and gender subgroups within each country. Correlations with the physical component were highest (0.64 to 0.86) for the Physical Functioning, Role Physical, and Bodily Pain scales, whereas the Mental Health, Role Emotional, and Social Functioning scales correlated highest (0.62 to 0.91) with the mental component. Secondary correlations for both clusters of scales were much lower. Scales measuring General Health and Vitality correlated moderately with both physical and mental health components. These results support the construct validity of the SF-36 translations and the scoring of physical and mental health components in all countries studied.  相似文献   
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This study tested the hypothesis that infants with iron-deficiency anemia show behaviors, such as increased proximity to caregivers, increased wariness or hesitance, and decreased activity, that could contribute to "functional isolation." The behavior of 52 Costa Rican 12- to 23-month-old infants with iron-deficiency anemia was contrasted with that of 139 comparison group infants with better iron status during free play and mental and motor testing and in the home. Infants with iron-deficiency anemia maintained closer contact with caregivers; showed less pleasure and delight; were more wary, hesitant, and easily tired; made fewer attempts at test items; were less attentive to instructions and demonstrations; and were less playful. Adult behavior also differed. The results indicate that iron-deficiency anemia in infancy is associated with alterations in affect and activity, suggesting that functional isolation is a useful framework for understanding poorer developmental outcome in iron-deficiency anemia, the world's most common single nutrient deficiency.  相似文献   
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介绍了一种碳酸盐岩储集层裂缝堵水的方法.对堵水工程的设计、工程实施过程中技术参数的变化以及在碳酸盐岩储集层中沿着注水井裂缝的堵水实验区开发方式进行了分析.  相似文献   
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An evaluation was done of respiratory failure in 149 children aged 3 to 15 presenting with funnel-shaped chest deformity (FCD). An original classification is suggested of degree of respiratory failure in FCD in children. Based on the index assessment of clinical and functional parameters an outline has been worked out for degree of respiratory failure. The criteria obtained are statistically significant; being able of giving quantitative assessment of degree of respiratory failure they can serve as control figures to be used in evaluations designed to study time course of changes in respiratory failure.  相似文献   
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