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971.
A. T. Adorno C. R. S. Beatrice A. V. Benedetti P. L. Cabot 《Journal of Materials Science》1993,28(2):411-414
Electrical resistivity measurements and scanning electron microscopy was used to study the dissolution of silver on Cu-Ag and Cu-Al-Ag alloys. The results seem to indicate that the dissolution temperature is affected by the addition of aluminium. 相似文献
972.
973.
D Brodaty G Dreyfus C Dubois P De Lentdecker C Barbagelatta PF Bouchet LJ Couderc O Bletry P Honderlick D Guilmet 《Canadian Metallurgical Quarterly》1998,91(12):1525-1529
The authors report a case of giant cell myocarditis leading to rapidly progressive cardiac failure despite immuno-suppressor treatment in a 20 year old woman. The cardiac failure was successfully managed by implantation of a left ventricular assist device and then cardiac transplantation. The problems encountered underline the importance of accurate diagnosis by endomyocardial biopsy before undertaking treatment and the difficulties in the choice of appropriate method of assistance in this indication. Giant cell myocarditis is a rare cause of cardiac failure and should be considered in the differential diagnosis in view of its clinical features and risk of progression. The literature and the therapeutic implications are discussed. 相似文献
974.
S Chasserot-Golaz P Hubert D Thiersé S Dirrig CJ Vlahos D Aunis MF Bader 《Canadian Metallurgical Quarterly》1998,70(6):2347-2356
Several lines of evidence suggest that phosphorylated products of phosphatidylinositol play critical functions in the regulation of membrane trafficking along the secretory pathway. To probe the possible involvement of phosphatidylinositol 3-kinase (PI 3-kinase) in regulated exocytosis, we have examined its subcellular distribution in cultured chromaffin cells by immunoreplica analysis and confocal immunofluorescence. We found that the PI 3-kinase heterodimer consisting of the regulatory and catalytic subunits was associated essentially with the subplasmalemmal cytoskeleton in both resting and nicotine-stimulated chromaffin cells. Attempts to immunoprecipitate PI 3-kinase with anti-phosphotyrosine antibodies failed, suggesting that the activity of PI 3-kinase was not modulated by tyrosine phosphorylation and/or physical interaction with SH2-containing proteins in stimulated chromaffin cells. LY294002 [2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one], a potent inhibitor of PI 3-kinase, produced a dose-dependent inhibition of catecholamine secretion evoked by various secretagogues. Furthermore, cytochemical experiments with rhodamine-labeled phalloidin revealed that LY294002 blocked the disassembly of cortical actin in chromaffin cells stimulated by a depolarizing concentration of potassium. Our results suggest that PI 3-kinase may be one of the important regulatory exocytotic components involved in the signaling cascade controlling actin rearrangements required for catecholamine secretion. 相似文献
975.
In 28 dogs, oral malodor was assessed organoleptically (0-3 scale) and by measurement of volatile sulfur components (VSC), using two positions ('intraoral' and 'tooth surface') for sampling VSC. Significant correlations were found between: intraoral and tooth surface VSC collection positions (p < 0.0001) and between organoleptic and tooth surface VSC data (p < 0.0001). VSC measurement is a sensitive, repeatable and non-subjective method of assessing oral malodor in dogs. 相似文献
976.
977.
AF da Silva P McCollum T Szymanska L de Cossart 《Canadian Metallurgical Quarterly》1996,83(10):1370-1372
A total of 700 patients who had carotid endarterectomy (CEA) in the UK and Ireland during a 6-month interval between March and August 1994 were studied prospectively. Some 108 patients (15.4 per cent) had a contralateral internal carotid artery occlusion. Previous reports have shown an associated stroke rate of about 10 per cent in these patients. This study assessed complications and outcome for patients undergoing CEA with contralateral internal carotid artery occlusion compared with those without. The indications for surgery were comparable between the two groups although the patients with occlusion had a slightly higher incidence of arrhythmia and stroke. Intraoperative shunts were used in a significantly higher proportion of those with occlusion (83.3 versus 64.7 per cent, P = 0.0001). The combined death and stroke rate for patients with occlusion was 5.6 per cent compared with 2.4 per cent for the remainder (P not significant). On the basis of the present data, CEA with a contralateral carotid artery occlusion carries only a slight increase in the rate of postoperative stroke and death. This increase was not statistically significant and is lower than that reported previously. 相似文献
978.
979.
OBJECTIVE: To evaluate the efficacy of exploratory vitrectomy for certain traumatized eyes with no light perception (NLP) and dense vitreous hemorrhage. METHOD: We performed vitrectomy on 10 patients with NLP eyes after ocular trauma. Of them, eight had open globe injuries and two had closed blunt ocular trauma. RESULTS: Postoperatively, six had visual acuities of light perception to 0.25 and four remained NLP. In most eyes, a potentially functional posterior retina and optic disc were observed during surgery. CONCLUSION: Dense vitreous hemorrhage could be the most important factor for NLP after severe ocular trauma. Therefore, NLP does not always mean permanent loss of vision. Proper primary repair of the wound and timely vitrectomy may give a chance of visual recovery in selected traumatized eyes. 相似文献
980.
Cordella L.P. De Stefano C. Tortorella F. Vento M. 《Neural Networks, IEEE Transactions on》1995,6(5):1140-1147
Criteria for evaluating the classification reliability of a neural classifier and for accordingly making a reject option are proposed. Such an option, implemented by means of two rules which can be applied independently of topology, size, and training algorithms of the neural classifier, allows one to improve the classification reliability. It is assumed that a performance function P is defined which, taking into account the requirements of the particular application, evaluates the quality of the classification in terms of recognition, misclassification, and reject rates. Under this assumption the optimal reject threshold value, determining the best trade-off between reject rate and misclassification rate, is the one for which the function P reaches its absolute maximum. No constraints are imposed on the form of P, but the ones necessary in order that P actually measures the quality of the classification process. The reject threshold is evaluated on the basis of some statistical distributions characterizing the behavior of the classifier when operating without reject option; these distributions are computed once the training phase of the net has been completed. The method has been tested with a neural classifier devised for handprinted and multifont printed characters, by using a database of about 300000 samples. Experimental results are discussed. 相似文献