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51.
52.
The temperature dependence of the diffusion of ammonia is studied by a new absorption spectroscopic method in 14 transparent filmforming polymers in the range from 15 to 90°C. A linear free-energie-relationship between the activation energy of the diffusion (ED) and the preexponential factor (D0) in the Arrhenius-equation corresponds to the behaviour of permanent gases in the glassy state of polymers, but the diffusion coefficients are approximately one order of magnitude lower. A comparison in the activation energies for the diffusion of oxygen and ammonia in three polymers shows that this is due to the decreased activation entropy rather than to a larger Van-der-Waals diameter. 相似文献
53.
Marx Elisabeth M.; Williams J. Mark; Claridge Gordon C. 《Canadian Metallurgical Quarterly》1992,101(1):78
20 depressed patients with major depressive disorder, 20 nondepressed matched control Ss, and 17 patients with anxiety disorders were compared in different measures of social problem solving. Problem solving was assessed with the Means-Ends Problem-Solving Test (Study 1), the solution of personal problems, and a problem-solving questionnaire (Study 2). Results showed that, as predicted, depressed Ss suffered from a deficit in problem solving in all 3 measures. The majority of these deficits were also displayed by the clinical control group rather than being specific to a diagnosis of depression. However, depressed Ss produced less effective solutions than did normal and clinical control Ss. The results suggest that depressed and anxious patients may have difficulties at different stages of the problem-solving process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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K. Millies F. Marx P. Schreier M. Kellert H. -P. Thier H. Miethke Kl. Guthy B. Fretzdorff K. Pfeilsticker H. -J. Kleinan J. Buchberger D. Eppert M. Teubner H. Wieczorek H. Ebertzhagen W. Groth M. Petz F. Kiermeier W. Hartmeier E. Lück F. I. Schäfers 《European Food Research and Technology》1986,183(6):426-434
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TI Huo JC Wu YH Huang UC Yang IJ Sheen FY Chang SD Lee 《Canadian Metallurgical Quarterly》1998,13(11):1138-1142
Despite advances in postnatal care, patients born with a congenital diaphragmatic hernia (CDH) suffer substantial morbidity and mortality. The present study was undertaken to determine the prognostic influence of prenatally-diagnosed liver herniation in the hemithorax in fetuses with CDH. The medical records of 48 patients evaluated for a prenatally-diagnosed left CDH were retrospectively reviewed. Patients were analysed according to the position of the liver by prenatal ultrasound; 32 fetuses had a major portion of the liver herniated into the left hemithorax ('liver up') and 16 had an intra-abdominal liver ('liver down'). Liver position was determined using colour-flow Doppler ultrasonography. There were two fetal deaths in the liver-up group and one in the liver-down group. The liver-up group more frequently required extracorporeal membrane oxygenation (ECMO) support (53 per cent) compared with the liver-down group (19 per cent). Postnatal survival was significantly less in the liver-up group (43 per cent) vs. the liver-down group (93 per cent). Fetuses with congenital diaphragmatic hernia and liver herniated into the hemithorax have a much worse prognosis than similarly afflicted fetuses without liver herniation. Prenatal ultrasonographic diagnosis of congenital diaphragmatic hernia allows for preparation for a critically ill newborn and aids in prenatal family counselling. 相似文献
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N Marx U Sch?nbeck MA Lazar P Libby J Plutzky 《Canadian Metallurgical Quarterly》1998,83(11):1097-1103
Mesenchymal hamartomas of the liver are the second most common benign liver tumor of childhood. The experience with this tumor at Egleston's Children Hospital at Emory University from 1989 to 1994 is reviewed. Eight patients presented with abdominal distention or an upper abdominal mass. Six patients presented at a mean age of 8 months, and two patients presented at 17 and 23 years of age, respectively. Four patients displayed normal alpha-fetoprotein levels, whereas one patient had an elevated level. Liver function studies were normal in all patients. Abdominal ultrasonography and CT scans revealed a cystic, septated mass within the liver or on a pedicle in all patients. Five patients had simple excision of the tumor, and two had major hepatic resections. The cysts were multiloculated and lined with cuboidal bile duct epithelium surrounded by stroma containing proliferating bile ducts, blood vessels, and compressed liver tissue with no calcifications. In one patient, some pathologists favored the diagnosis of malignant myxoid fibrous histiocytoma because of similar-appearing stroma. Follow-up (mean, 35 months) revealed one symptomatic recurrence after initial resection was incomplete. There were no other recurrences and no malignant transformations. A septated, noncalcified, cystic hepatic mass in an infant with normal liver function studies and characteristic ultrasound or CT is likely a benign mesenchymal hamartoma that can be cured by total local excision. 相似文献
60.
This study investigates the relation between performance on simple tasks dependent on proprioception, and performance of complex perceptual-motor skills in clumsy children and age-matched control children. One hundred and forty-six right-handed children aged between 5 and 8 years were tested on non-visual aiming, non-visual posture matching, the Kinaesthetic Sensitivity Test (KST), and the Movement Assessment Battery for Children (ABC). Half of the children had scores below the 15th centile on the Movement ABC and were classed into the developmental coordination disorder (clumsiness) group. Scores on the proprioceptive tasks were used to predict performance on complex tasks of the subscales of the Movement ABC (manual dexterity, ball skills, and balance). Specific relations were found between the proprioceptive tasks and the subscales of the Movement ABC, but the KST did not predict differences in motor skills, and no relation was found between tasks carried out without vision. Simple non-visual movement tasks do predict performance in more complex skilled tasks but this is affected by many task features rather than simply the reliance on proprioception for information about movement. 相似文献