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1.
INTRODUCTION: Heterozygous beta-thalassemia manifests hematologically with microcytosis, reduced red blood cell hemoglobin concentration and high hemoglobin A2 levels. Almost all molecular alterations are due to point mutations. We attempt to determinate the frequency of that mutations in the Oriental Andalusia Area, and its relationship with the hematological phenotype. PATIENTS AND METHODS: We have studied 45 heterozygous patients. DNA samples were amplified by PCR, using the printers CD7 and HI1. A 16 Kb fragment corresponding to beta globin gene was obtained and analyzed by Dot Blot assay and hybridized with allelic specific oligonucleotide (ASO) probes to detect the 6 more frequent mutations found in the South of Spain. RESULTS: Codon 39 nonsense mutation (31.1%) was the most frequent finding followed by IVS-1 NT 110 (26.7%). The relationship between hematological parameters and molecular mutations concluded that IVS-I NT 6 mutation developed a minimal anemia. DISCUSSION: From the practical point of view, this study indicates that we were able to detect more than 90% of heterozygous beta-tal. with 5 out of 6 ASO probes used in this work. Thus, our data also provides a further implication in prenatal diagnosis.  相似文献   
2.
Nowadays any Knowledge Based System (KBS) realization needs of intercommunication among distributed components and to use non-connected and distributed data sources, which poses several challenges to the classical Artificial Intelligence field of KBS.

The multiagent paradigm and the use of ontologies are considered to be suitable tools to face the problems of designing and developing today KBS. On the other hand, using such networked KBS through handheld devices makes more efficient exploitation and interaction with the system.

This paper presents an open and flexible architecture for a distributed KBS and an application of it to construct a system for Psychological Disorders consulting, the so called PDA2 (Psychological Disorder Assistant through PDA). We analyze the main features of the architecture as well as the agent tools we may use to construct it. Additionally, we present a support ontology for Psychological Disorders.  相似文献   

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An efficient method for computing the fields of large scatterers is presented. The current is expanded in terms of modes defined as complex exponential functions. The modes are represented efficiently by means of spline functions. Analytical expressions have been obtained to compute efficiently the fields due to the current modes.  相似文献   
5.
We present the results of modeling the response of a Rotating Polarizer Interferometer (RPI), an actual design and the evaluation of it. The RPI was introduced almost 10 years ago by Erickson [1] and since then it has not received too much attention from the millimeter wave community despite its very attractive characteristics, this is perhaps due to a lack of proven designs to encourage potential users. Here we show that with proper design equations a predictable result can be achieved and that a working device with a low-loss dielectric filling (Teflon) is feasible  相似文献   
6.
Computer-aided engineering tools are routinely used to simulate forging and heat-treatment operations and to perform thermal and stress analyses. This review gives a few examples of the current uses of process modeling tools and outlines some developing capabilities and near-term applications.  相似文献   
7.
In this article, a simple and inexpensive experimental technique easy to build in laboratory, for the measurement of tortuosity of a packed bed of inert particles, is described. Experimental values of the tortuosity were obtained with four different packed beds of sand. The experimental results obtained are in good agreement with the theoretical values of tortuosity in a porous media; and the data reported showed the tortuosity to increase with decrease in the void fraction of the packed bed as expected.  相似文献   
8.
Molecular (or tracer) diffusion coefficient data were obtained for 2-naphthol, benzoic acid, salicylic acid, camphor, and cinnamic acid in water at temperatures that differ significantly from ambient value. Experimental values were determined for the dissolution of 2-naphthol in water at 283 to 368 K, of benzoic acid in water at 283 to 338 K, of salicylic acid in water at 283 to 343 K, of camphor in water at 283 to 318 K, and of cinnamic acid in water at 283 to 318 K. Empirical correlations are presented for the prediction of molecular diffusion coefficient over the entire range of temperatures studied, and they are shown to predict the obtained data with very good accuracy.  相似文献   
9.
Functionalized latexes coated by antibodies are used in diagnostic tests for the detection of antigens in biological fluids. A simple kinetic model is presented which is related to the optical monitoring of the formation of specific complexes between antigen and antibody amplified by latex beads. The antibodies are chemically coupled onto chloromethylstyrene (CMST) particles. The kinetic model is able to describe the immunoprecipitin curves of immunolatex beads. The number of fitting parameters is relatively reduced (only three), and the meaning of these parameters can be interpreted in terms of the chemical equilibrium constant, the percentage of active IgG on the latex beads, and optical response. The model explains very well the optical response of immunolatex prepared by covalent coupling of antibodies on polymer carriers.  相似文献   
10.
Summary Three copolymers of ethylene and 1-decene, covering a wide range of compositions, have been synthesized with a MgCl2-supported Ziegler-Natta catalyst. The analysis by DSC and X-ray shows a great degree of heterogeneity in these copolymers and appreciable levels of crystallinity, corresponding to the orthorhombic lattice of polyethylene, are present even for very high 1-decene contents.  相似文献   
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