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Nicolae Danet 《Proceedings of the American Mathematical Society》2001,129(2):539-542
If and are Banach lattices such that is separable and has the countable interpolation property, then the space of all continuous regular operators has the Riesz decomposition property. This result is a positive answer to a conjecture posed by A. W. Wickstead.
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Cholinesterase immobilisation on the surface of screen-printed electrodes based on concanavalin A affinity 总被引:1,自引:0,他引:1
This paper reports a new method for the immobilisation of acetylcholine esterase (AChE) on the surface of screen-printed electrodes (SPEs) based on the affinity between the glycoprotein enzyme and concavalin A (Con A). The surface of the working electrode has been modified with a Nafion layer that contains graphite, the mediator 7,7,8,8-tetracyanoquinodimethane (TCNQ) and heptylamine. The enzyme-free SPEs were characterised by cyclic voltammetry in buffer solutions and amperometry using cysteamine as analyte. The AChE immobilisation process leads to the sandwich structure: electrode-carbohydrate-Con A-enzyme. The first step of the immobilisation is the covalent activation of an amino group bound in a Nafion layer. The following steps are based on the affinity. The non-specific adsorption has been totally eliminated using BSA solutions at two different pHs. Various amounts of enzyme, from 0.1 to more than 2 mIU AChE, have been loaded on the electrode surface. The method offers the advantage of a free diffusion, which allows obtaining a response time of less than 2 min. An operational stability of more than 10 measurements was registered, while the active surface of the electrode was successfully reloaded for three consecutive times without any important change of the analytical performances. 相似文献
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Yan X MacLeod AM Gillespie WA Knippels GM Oepts D van Der Meer AF Seidel W 《Physical review letters》2000,85(16):3404-3407
Time-resolved measurements of the transverse electric field associated with relativistic electron bunches are presented. Using an ultrafast electro-optic sensor close to the electron beam, the longitudinal profile of the electric field was measured with subpicosecond time resolution and without time-reversal ambiguity. Results are shown for two cases: inside the vacuum beam line in the presence of wake fields, and in air behind a beryllium window, effectively probing the near-field transition radiation. Especially in the latter case, reconstruction of the longitudinal electron bunch shape is straightforward. 相似文献
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T. Tomiyama H. Suetomi R. A. Schrabstein R. Danet G. J. Sizoo C. P. Koene und R. Kolkwitz 《Fresenius' Journal of Analytical Chemistry》1939,118(5-6):187-188
Ohne Zusammenfassung 相似文献
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Claudia Valentina Popa Liliana Lungu Ligia Florentina Cristache Crinu Ciuculescu Andrei Florin Danet 《Natural product research》2015,29(18):1744-1747
To gain new insight into the antimicrobial potential of Ailanthus altissima Swingle, ethanol leaf extracts were evaluated for the antifungal effects against the model yeast Saccharomyces cerevisae. The extracts inhibited the yeast growth in a dose-dependent manner, and this effect could be augmented by heat shock, exposure to visible light or exposure to high concentrations of Ca2+. Using transgenic yeast cells expressing the Ca2+-dependent photoprotein, aequorin, it was found that the leaf extracts induced cytosolic Ca2+ elevation. Experiments on yeast mutants with defects in Ca2+ transport demonstrated that the cytotoxicity of the A. altissima leaf extracts (AaLEs) was mediated by transient pulses of Ca2+ ions which were released into the cytosol predominantly from the vacuole. The investigation of the antifungal synergies involving AaLEs may contribute to the development of optimal and safe combination therapies for the treatment of drug-resistant fungal infections. 相似文献