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M Miranda F Amicarelli AR Volpe A Poma L Masciocco M Carmignani 《Canadian Metallurgical Quarterly》1993,24(6):1319-1322
1. The present paper reports the effects of liposome-entrapped tyrosinase (EC 1.14.18.1. L-Tyrosine, L-3,4-dihydroxyphenylalanine: oxygen oxidoreductase) infusion on the catecholamine contents of rat plasma. The actions of liposomes and free tyrosinase have also been investigated. 2. From the experiments, evidence has been obtained that liposome-entrapped tyrosinase is able to affect specifically L-3,4-dihydroxyphenylalanine (L-DOPA) levels which increase dramatically. 3. The possible use of liposome-entrapped tyrosinase to raise L-DOPA levels in catecholamine related disorders is discussed. 4. Liposomes without tyrosinase provoke no significant changes of catecholamine or L-DOPA levels while free tyrosinase does induce a change but in a less constant fashion than the liposome-entrapped enzyme. 相似文献
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Time-scaling properties of the isothermal transformation kinetics have been tested for three Fe-B-based metallic glasses exhibiting two crystallization stages. The time scale was defined as the time at which crystallization has reached half completion and is derived from calorimetric (DSC) data. The temperature dependence of the time-scaling parameter shows a lowtemperature freezing behaviour and can be described by empirical functions based on free-volume considerations. 相似文献
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OBJECTIVE: To analyze the short- and medium-term results of the Burch-like urethropexy with bone anchors in the treatment of genuine stress urinary incontinence. METHODS: We performed the conventional Burch technique which was modified with the use of 4 bone anchors for bony fixation. Forty-four female patients with genuine stress urinary incontinence were operated on from November, 1995 to November, 1997. RESULTS: The patients had a bladder catheter indwelling for 4 to 9 days and only 3 of them required intermittent catheterization during two months. All patients recovered spontaneous micturition. The postoperative urinary continence was 93% at a mean follow-up of 11 months. CONCLUSIONS: Although our initial results seem encouraging, a continuous and objective follow-up is warranted to assess the long-term efficacy of this technique. 相似文献
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NP Pereira TM Monteiro AC Freitas EJ Barreiro AL Miranda 《Canadian Metallurgical Quarterly》1998,137(3):82-86
A new series 5-thio aryl pyrazole derivatives were proposed aiming analgesic activity. In this work, 8 new compounds of this class were synthesized using usual synthetic methodology, having as key intermediate the 3-methyl-4-nitro-5-chloropyrazole-1-phenyl derivative and subsequent reaction with several nucleophiles sulfides. Pharmacological evaluation of this series showed analgesic activity in the some extent in especially for 5-(4-bromophenyl)-thio-3-methyl-4-nitro-1-phenylpyrazole which was the most potent in this series, presenting an analgesic action comparable to that show by dipyrone. 相似文献
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A. H. Bott J. C. Suita A. G. da Silva P. E. V. de Miranda 《Surface & coatings technology》1995,70(2-3):257-260
1H(,p) 4He scattering cross-sections were determined for the 6.5–13 MeV (incident energy) range, thereby extending the energy range for such data beyond that available in the literature. These values are essential for the further development of hydrogen concentration profiling by the transmission elastic recoil detection technique, of particular interest in the design of surface-engineered hydrogen contamination barriers for steels. 相似文献
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Beatriz Miranda Eva Díaz Salvador Ordez Fernando V. Díez 《Catalysis communications》2006,7(12):945-949
The performance of 0.5% Ru/Al2O3 for the deep oxidation of trichloroethene (1000–2500 ppmV, WHSV = 55 h−1) in air was studied in this work. Experiments were carried out both at dry and wet (20,000 ppmV of H2O) conditions. Catalytic performance was studied in terms of activity and selectivity for the different reaction products (CO2, HCl, Cl2, C2Cl4, CCl4 and CHCl3). Both the activity and the selectivity for total combustion are higher than other catalysts suggested in the literature for this process (especially Pd and Pt).The main organic by-products are CCl4 and CHCl3, whereas in all the other catalysts tested in the literature, tetrachloroethene is the main organic by-product. This fact suggests that the mechanism of the combustion reaction, involving a double-bond scission, is essentially specific for this catalyst.Kinetic data was fit to a pseudo-first order kinetic expression, providing fairly good fit. 相似文献