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21.
Protein C activity was determined in 70 patients with liver disease, 30 with acute viral hepatitis and 40 with liver cirrhosis. Statistical comparison of the values for patients with those for healthy Ivorians showed a significant decrease in protein C activity, positively correlated with a prolongation of the prothrombin time.  相似文献   
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Microsystem Technologies - In this work, we propose a geometrical analysis of a biosensor with microelectrodes of interdigitated structures, based on the method of impedance spectroscopy in the...  相似文献   
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In this article we describe a demonstrator that shows how the cognitive resource manager (CRM) and the radio-environmental map (REM) can be efficiently implemented in full commercial grade cellular system (i.e., LTE system). The demonstrator shows how the modular CRM together with its open interface, the universal link-layer API (ULLA), facilitates the implementation of efficient radio resource management techniques guaranteeing the quality of service in the LTE system. The CRM, through ULLA, is able to obtain PHY/MAC status information of the link between the tested eNode B and the user equipment, and reconfigure link parameters. This measure-and-control by CRM/ULLA is independent of the underlying radio access technology, which shows the neutrality of CRM/ULLA towards PHY/MAC characteristics. The article also shows how the REM can be easily implemented in such system and how the REM provides the CRM with environmental information that enhances system management performance.  相似文献   
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Summary The principle of maximum entropy is used under two different sets of mean value constraints to analyse a stableG/G/1 queue withR priority classes under preemptive-resume (PR) and non-preemptive head-of-line (HOL) scheduling disciplines. New one-step recursions for the maximum entropy state probabilities are established and closed form approximations for the marginal queue length distribution per priority class are derived. To expedite the utility of the maximum entropy solutions exact analysis, based on the generalised exponential (GE) distribution, is used to approximate the marginal mean queue length and idle state probability class constraints for both the PR and HOLG/G/1 priority queues. Moreover, these results are used as building blocks in order to provide new approximate formulae for the mean and coefficient of variation of the effective priority service-time and suggest a maximum entropy algorithm for general open queueing networks with priorities in the context of the reduced occupancy approximation (ROA) method. Numerical examples illustrate the accuracy of the proposed maximum entropy approximations in relation to simulations involving different interarrival-time and service-time distributions per class. Comments on the extension of the work to more complex types of queueing systems are included.This work is sponsored in part by the Science and Engineering Research Council (SERC), UK, under grant GR/D/12422 and in part by the Ministry of Higher Education of the Algerian Government  相似文献   
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Intimal hyperplasia, a vascular pathology characterized by vessel wall thickening, is implicated in vein graft failures. For efficient prevention, a biodegradable drug delivery system should be applied externally to the graft for an extended time. Finding a gel suitable for such a system is challenging. We have synthesized HA-Dopamine conjugates (HA-Dop) with several degrees of substitution (DS) and used two crosslinking methods: initiator-free crosslinking by basic pH shift or commonly used crosslinking by a strong oxidizer, sodium periodate. The rheological properties, bioadhesion to vascular tissue, cytocompatibility with fibroblasts have been compared for both methods. Our results suggest that initiator-free crosslinking provides HA-Dop gels with more adequate properties with regards to vascular application than crosslinking by strong oxidizer. We have also established the cytocompatibility of the initiator-free crosslinked HA-Dop gels and the cytotoxicity of dopamine-sodium periodate combinations. Furthermore, we have incorporated a drug with anti-restenotic effect in perivascular application, atorvastatin, into the gel, which showed adequate release profile for intimal hyperplasia prevention. The oxidizer-free formulation with improved bioadhesion holds promise as an efficient and safe drug delivery system for vascular applications.  相似文献   
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In this paper, we propose an evolution of adaptive power control algorithms for Universal Mobile Telecommunications System (Umts). The proposed mechanism uses an adaptive power step to carry out with high fluctuations in the radio interface. Furthermore, we propose the integration of a stabilization zone where the transmitted power is kept constant to reduce oscillations around the target QoS level. In this algorithm, only the interpretation of power control feedback commands is ameliorated by adding some intelligence to mobiles and base stations. Moreover, the standardized radio interface protocol is used without modification. The algorithm can be used in both link directions of the Frequency Division Duplex (Fdd) mode and in the downlink of the Time Division Duplex (Tdd) mode, where closed-loop power control algorithms are used. Simulation results show that the proposed algorithm decreases the outage probability and reduces drastically the transmitted power, which are the main objectives of power control algorithms.  相似文献   
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