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A novel flow-injection chemiluminescence-based method has been developed for determination of superoxide dismutase (SOD) activity. An in-vitro superoxide anion generation xanthine/xanthine oxidase stable source was established on line with FIA/CL-detection apparatus, for measuring SOD activity. This method can detect SOD in the linear range of 0.002–2.00 U mL–1 with a detection limit of 0.001 U mL–1. Another method for detection of superoxide anion is based on the luminol–FeCl3 chemiluminescence (CL) reaction. This method was used to evaluate superoxide release and SOD activity in rats treated with the traditional Chinese herb Pulsatilla chinensis, which resulted in high clearance of hepatitis B virus (HBV) after treatment of a hepatitis B patient. Interestingly, we found that treatment with Pulsatilla chinensis can specifically increase superoxide release by liver tissues and, at the same time, slightly increase extracellular SOD (ECSOD) activity in plasma; in particular it can markedly increase MnSOD activity in mitochondria in liver tissue. This work revealed a possible mechanism whereby Pulsatilla chinensis prevents possible infection (for example HBV) by specifically increasing superoxide release in the liver and increasing MnSOD activity to minimize superoxide-mediated toxicity.  相似文献   
23.
In this work we determine the group of modular automorphisms of the Drinfeld modular curve for any nonconstant polynomial .Received: 19 September 2002  相似文献   
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For Ω bounded and open subset of andX a reflexive Banach space with 1-symmetric basis, the function spaceJF X (Ω) is defined. This class of spaces includes the classical James function space. Every member of this class is separable and has non-separable dual. We provide a proof of topological nature thatJF X (Ω) does not contain an isomorphic copy of ℓ1. We also investigate the structure of these spaces and their duals.  相似文献   
25.
We analyze the deformation parameters and potential energy of a fissioning nucleus in the prefission state, along with its surface, Coulomb, and full kinetic energies.  相似文献   
26.
We review the recent progress made in understanding instantons at finite temperature (calorons) with non-trivial holonomy, and their monopole constituents as relevant degrees of freedom for the confined phase.  相似文献   
27.
The main paper conservation methods are presented, classified in the following categories: preparation of the intervention, disinfestation and disinfection/sterilization, surface/dry cleaning, wet cleaning, chemical stabilization, paper repairs, consolidation and strengthening. Treatment documentation is also discussed. The targets, the historical aspects, the general principles, the materials and equipment, the acceptance and criticism pertaining to each method are briefly reviewed, and the most important research for their evaluation is presented. Several paper stabilization strategies, such as deacidification and iron gall ink stabilization, applicable to paper are elucidated. Specific consolidation and strengthening methods for paper, such as lamination and paper splitting are also discussed. The review mainly focuses on the established methods, but experimental, abandoned or insufficiently documented methods are also included. Shortcomings and limitations of several methods were found in the literature, concerning health issues, limited effectiveness, adverse side-effects on the treated artefacts and restricted applicability.  相似文献   
28.
In this paper, we present sufficient conditions involving limsup which guarantee the oscillation of all solutions of a differential equation with non-monotone deviating argument and non-negative coefficients. Corresponding differential equations of both delayed and advanced type are studied. Using algorithms on MATLAB software, examples are given to demonstrate the advantage of our results.  相似文献   
29.
The Hotelling’s χ2 control chart is one of the most widely used multivariate charting procedures for monitoring the vector of means of several quality characteristics. As a Shewhart-type control chart, it incorporates information pertaining to most recently inspected sample and subsequently it is relatively insensitive in quickly detecting small magnitude shifts in the process mean vector. A popular solution suggested to overcome this handicap was the use of runs and scans rules as criteria to declare a process out-of-control. During the last years, the examination of Hotelling’s χ2 control charts supplemented with various runs rules has attracted continuous research interest. In the present article we study the performance of the Hotelling’s χ2 control chart supplemented with a r-out-of-m runs rule. The new control chart demonstrates an improved performance over other competitive runs rules based control charts.  相似文献   
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