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The aim of this study was to investigate the possible role of excitatory amino acids (EAAs) and cysteine in the development of brain damage after hypoxia-ischemia (HI) in neonates. In a rat model of neonatal HI, changes in extracellular (ec) amino acids in cerebral cortex were measured with microdialysis and correlated with the extent of brain damage at the site of probe placement. Extracellular concentrations of glutamate, aspartate and cysteine increased during HI and remained elevated during reperfusion. During HI the pattern of EAA changes was the same in the infarcted, undamaged and border zone regions. During reperfusion, however, the ec concentrations of glutamate, aspartate and cysteine were higher in infarcted and border zone areas compared to undamaged tissue. HI also produced a slight increase of tissue concentration of cysteine and decrease of tissue concentration of glutamate in parietal cortex of the HI hemisphere. The effect of cysteine on brain damage induced by HI and glutamate was also investigated. A subtoxic dose of cysteine potentiated glutamate toxicity in the arcuate nucleus and enhanced brain infarction after HI in neonatal rats. The results show that in neonatal HI the extracellular levels of EAAs during HI are not directly related to brain injury but the EAA levels during reflow predict the extent of infarction. Cysteine increases HI-induced brain injury and potentiates glutamate toxicity in neonatal rats. Speculatively, elevated level of cysteine during reperfusion may participate in the excitotoxic cascade leading to brain injury.  相似文献   
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Two hundred consecutively seen patients who had an injury to either the anterior cruciate ligament or the medial collateral ligament, or both, were randomly allocated to treatment by either conservative or a surgical regimen. Injuries to the medial collateral ligament could not be demonstrated to benefit from surgical treatment in any respect--with or without surgery the results were excellent. With injuries to the anterior cruciate ligament, recovery was more rapid without surgery but otherwise the results differed between the groups in only one respect: the pivot-shift test was more often positive after conservative treatment. The results were good in both treatment groups even though most of the patients who had an injury of the anterior cruciate ligament were somewhat less pleased with the outcome after a period of time.  相似文献   
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Nutritional dwarfing refers to a condition in which maladaptive eating patterns play a primary role in poor linear growth and delayed pubertal development. The present controlled study assesses whether nutritionally dwarfed children and adolescents differ in their psychosocial adjustment from healthy children and adolescents of comparable height in ways that might account for their undernutrition. Children with nutritional dwarfing (n = 16) were compared by standardized questionnaires with a short-stature (ie, heights below the fifth percentile) control group composed of children and adolescents with constitutional growth delay and/or familial short stature (n = 31). Scores on a self-report screening questionnaire for eating disorders did not differentiate the groups. Moreover, the vast majority of nutritionally dwarfed patients expressed a desire to have a heavier physical appearance. Whereas the groups were generally similar in self-perceptions of domain-specific competencies and positive psychosocial adjustment, the parents of nutritionally dwarfed children reported that their children showed significantly fewer externalized behavior problems. These findings suggest the existence of an eating disturbance that compromises growth in childhood and/or adolescence which, unlike anorexia nervosa, is not associated with evidence of psychopathology.  相似文献   
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The ulcerogenic effect of five different salts of alprenolol were tested against placebo in a porcine oesophageal test model. The salts with high water solubility, such as the hydrochloride and the fumarate, gave rise to the highest plasma concentrations of alprenolol and evoked serious oesophageal lesions, while the salts with low solubility-the benzoate, maleate and sebacate-had no irritative effect on the oesophagus. The plasma levels of alprenolol were much higher following administration of alprenolol hydrochloride in the oesophagus than after an identical intraduodenal dose of the same salt possibly because of the avoidance of the first-pass degradation during oesophageal absorption.  相似文献   
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Summary Two hundred patients were randomly selected for either a partial or a total meniscectomy for a meniscal tear during open operation. They were followed for a median of 7.8 years after operation. After partial meniscectomy, posterior horn tears had the worst outcome, but this was only apparent when more than two-thirds of the meniscus had been removed. The amount of meniscal tissue excised was inversely related to the function of the knee, except with bucket-handle tears treated by partial meniscectomy. Patients with bucket-handle, anterior and posterior horn tears had similar functional results after total meniscectomy. Preservation of the peripheral rim of the meniscus following partial meniscectomy produces the best functional results.
Résumé Deux cents patients atteints de lésion méniscale ont été répartis en cours d'opération, de façon randomisée, entre méniscectomie partielle et méniscectomie totale. Ces patients ont été revus, au dernier examen, de 6.3 à 9.8 ans après l'intervention (à 7.8 ans en moyenne). Après méniscectomie partielle c'étaient les lésions de la corne postérieure qui avaient les moins bons résultats fonctionnels, mais les différences de résultat selon les types de lésion n'étaient observées que lorsque plus d'un tiers de la surface méniscale avait été réséquée. La quantité de tissu méniscal enlevé était inversement proportionnelle à la qualité de la fonction du genou, sauf dans les déchirures en anse de seau traitées par méniscectomie partielle. Ces lésions étaient celles où la plus forte proportion de tissu méniscal avait été réséquée, mais dont les résultats fonctionnels étaient meilleurs que ceux des lésions de la corne postérieure. Les patients présentant des anses de seau, des lésions de la corne antérieure ou de la corne postérieure, avaient des résultats fonctionnels similaires après méniscectomie totale. La conservation de la périphérie du ménisque après méniscectomie partielle est le facteur essentiel d'un bon résultat fonctionnel post-opératoire.
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