978 resultados para Series Summation Method
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The Topliss method was used to guide a synthetic path in support of drug discovery efforts toward the identification of potent antimycobacterial agents. Salicylic acid and its derivatives, p-chloro, p-methoxy, and m-chlorosalicylic acid, exemplify a series of synthetic compounds whose minimum inhibitory concentrations for a strain of Mycobacterium were determined and compared to those of the reference drug, p-aminosalicylic acid. Several physicochemical descriptors (including Hammett`s sigma constant, ionization constant, dipole moment, Hansch constant, calculated partition coefficient, Sterimol-L and -B-4 and molecular volume) were considered to elucidate structure-activity relationships. Molecular electrostatic potential and molecular dipole moment maps were also calculated using the AM1 semi-empirical method. Among the new derivatives, m-chlorosalicylic acid showed the lowest minimum inhibitory concentration. The overall results suggest that both physicochemical properties and electronic features may influence the biological activity of this series of antimycobacterial agents and thus should be considered in designing new p-aminosalicylic acid analogs.
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Lychnophora ericoides Mart. (Asteraceae, Vernonieae) is a plant, endemic to Brazil, with occurrence restricted to the ""cerrado"" biome. Traditional medicine employs alcoholic and aqueous-alcoholic preparations of leaves from this species for the treatment of wounds, inflammation, and pain. Furthermore, leaves of L. ericoides are also widely used as flavorings for the Brazilian traditional spirit ""cachaca"". A method has been developed for the extraction and HPLC-DAD analysis of the secondary metabolites of L. ericoides leaves. This analytical method was validated with 11 secondary metabolites chosen to represent the different classes and polarities of secondary metabolites occurring in L. ericoides leaves, and good responses were obtained for each validation parameter analyzed. The same HPLC analytical method was also employed for online secondary metabolite identification by HPLC-DAD-MS and HPLC-DAD-MS/MS, leading to the identification of di-C-glucosylflavones, coumaroylglucosylflavonols, flavone, flavanones, flavonols, chalcones, goyazensolide, and eremantholide-type sesquiterpene lactones and positional isomeric series of chlorogenic acids possessing caffeic and/or ferulic moieties. Among the 52 chromatographic peaks observed, 36 were fully identified and 8 were attributed to compounds belonging to series of caffeoylferuloylquinic and diferuloylquinic acids that could not be individualized from each other.
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The structure constants of quantum Lie algebras depend on a quantum deformation parameter q and they reduce to the classical structure constants of a Lie algebra at q = 1. We explain the relationship between the structure constants of quantum Lie algebras and quantum Clebsch-Gordan coefficients for adjoint x adjoint --> adjoint We present a practical method for the determination of these quantum Clebsch-Gordan coefficients and are thus able to give explicit expressions for the structure constants of the quantum Lie algebras associated to the classical Lie algebras B-l, C-l and D-l. In the quantum case the structure constants of the Cartan subalgebra are non-zero and we observe that they are determined in terms of the simple quantum roots. We introduce an invariant Killing form on the quantum Lie algebras and find that it takes values which are simple q-deformations of the classical ones.
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The purpose is to present the studies of RET gene expression and acetylcholinesterase activity in 23 patients operated for Hirschsprung`s disease (HD). The patients underwent either transanal endorectal pull-through or Duhamell`s procedure. Full-thickness intestinal samples from the three different segments (ganglionic, intermediate and aganglionic) were collected. Each tissue sample was divided in two portions, one for AChE histochemical staining and the other for examination of RET mRNA expression level. All patients had an uneventful postoperative recovery. In all patients, the AChE stainings demonstrated the absence of activity in the ganglionic area, the marked increase of positive fibers in the aganglionic area, and little increase of positive fibers in the intermediate area. In the ganglionic and intermediate areas, all patients (100%) showed significant RET gene expression. In the aganglionic area, 18 patients (78.3%) did not present gene expression and the other five patients (21.7%) presented gene expression that was similar to the ganglionic and intermediate areas. The results reinforce the conclusion that the method of AChE staining is effective for the diagnosis of intestinal aganglionosis and confirm the knowledge that genes beyond RET may be implicated in the genesis of sporadic cases of HD.
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Recently, Barrett's esophagus and early adenocarcinomas have been detected increasingly frequently in routine follow-up of patients with gastroesophageal reflux. Although surgery is the treatment of choice, some patients are medically unfit for esophagectomy and, in this case, the only alternative curative therapy is radical chemoradiation therapy. In addition, some patients who present with symptoms have small tumors that cannot be localized accurately using routine imaging techniques. This report describes a series of eight patients with small esophageal cancers in whom the tumors were successfully localized following endoscopic injection of contrast, and treated with chemoradiation therapy. The treatment was successful in seven patients. This method of tumor localization demonstrated that conventional techniques are mostly, unreliable when applied to very early cancers.
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A new method to extract MOSFET's threshold voltage VT by measurement of the gate-to-substrate capacitance C-gb of the transistor is presented. Unlike existing extraction methods based on I-V data, the measurement of C-gb does not require de drain current to now between drain and source thus eliminating the effects of source and drain series resistance R-S/D, and at the same time, retains a symmetrical potential profile across the channel. Experimental and simulation results on devices with different sizes are presented to justify the proposed method.
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A detailed analysis procedure is described for evaluating rates of volumetric change in brain structures based on structural magnetic resonance (MR) images. In this procedure, a series of image processing tools have been employed to address the problems encountered in measuring rates of change based on structural MR images. These tools include an algorithm for intensity non-uniforniity correction, a robust algorithm for three-dimensional image registration with sub-voxel precision and an algorithm for brain tissue segmentation. However, a unique feature in the procedure is the use of a fractional volume model that has been developed to provide a quantitative measure for the partial volume effect. With this model, the fractional constituent tissue volumes are evaluated for voxels at the tissue boundary that manifest partial volume effect, thus allowing tissue boundaries be defined at a sub-voxel level and in an automated fashion. Validation studies are presented on key algorithms including segmentation and registration. An overall assessment of the method is provided through the evaluation of the rates of brain atrophy in a group of normal elderly subjects for which the rate of brain atrophy due to normal aging is predictably small. An application of the method is given in Part 11 where the rates of brain atrophy in various brain regions are studied in relation to normal aging and Alzheimer's disease. (C) 2002 Elsevier Science Inc. All rights reserved.
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A new wavelet-based adaptive framework for solving population balance equations (PBEs) is proposed in this work. The technique is general, powerful and efficient without the need for prior assumptions about the characteristics of the processes. Because there are steeply varying number densities across a size range, a new strategy is developed to select the optimal order of resolution and the collocation points based on an interpolating wavelet transform (IWT). The proposed technique has been tested for size-independent agglomeration, agglomeration with a linear summation kernel and agglomeration with a nonlinear kernel. In all cases, the predicted and analytical particle size distributions (PSDs) are in excellent agreement. Further work on the solution of the general population balance equations with nucleation, growth and agglomeration and the solution of steady-state population balance equations will be presented in this framework. (C) 2002 Elsevier Science B.V. All rights reserved.
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Introduction / Aims: Adopting the important decisions represents a specific task of the manager. An efficient manager takes these decisions during a sistematic process with well-defined elements, each with a precise order. In the pharmaceutical practice and business, in the supply process of the pharmacies, there are situations when the medicine distributors offer a certain discount, but require payment in a shorter period of time. In these cases, the analysis of the offer can be made with the help of the decision tree method, which permits identifying the decision offering the best possible result in a given situation. The aims of the research have been the analysis of the product offers of many different suppliers and the establishing of the most advantageous ways of pharmacy supplying. Material / Methods: There have been studied the general product offers of the following medical stores: A&G Med, Farmanord, Farmexim, Mediplus, Montero and Relad. In the case of medicine offers including a discount, the decision tree method has been applied in order to select the most advantageous offers. The Decision Tree is a management method used in taking the right decisions and it is generally used when one needs to evaluate the decisions that involve a series of stages. The tree diagram is used in order to look for the most efficient means to attain a specific goal. The decision trees are the most probabilistic methods, useful when adopting risk taking decisions. Results: The results of the analysis on the tree diagrams have indicated the fact that purchasing medicines with discount (1%, 10%, 15%) and payment in a shorter time interval (120 days) is more profitable than purchasing without a discount and payment in a longer time interval (160 days). Discussion / Conclusion: Depending on the results of the tree diagram analysis, the pharmacies would purchase from the selected suppliers. The research has shown that the decision tree method represents a valuable work instrument in choosing the best ways for supplying pharmacies and it is very useful to the specialists from the pharmaceutical field, pharmaceutical management, to medicine suppliers, pharmacy practitioners from the community pharmacies and especially to pharmacy managers, chief – pharmacists.
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Mestrado em Medicina Nuclear.
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This paper presents the Pseudo phase plane (PPP) method for detecting the existence of a nanofilm on the nitroazobenzene-modified glassy carbon electrode (NAB-GC) system. This modified electrode systems and nitroazobenze-nanofilm were prepared by the electrochemical reduction of diazonium salt of NAB at the glassy carbon electrodes (GCE) in nonaqueous media. The IR spectra of the bare glassy carbon electrodes (GCE), the NAB-GC electrode system and the organic NAB film were recorded. The IR data of the bare GC, NAB-GC and NAB film were categorized into five series consisting of FILM1, GC-NAB1, GC1; FILM2, GC-NAB2, GC2; FILM3, GC-NAB3, GC3 and FILM4, GC-NAB4, GC4 respectively. The PPP approach was applied to each group of the data of unmodified and modified electrode systems with nanofilm. The results provided by PPP method show the existence of the NAB film on the modified GC electrode.
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In this work, we present the explicit series solution of a specific mathematical model from the literature, the Deng bursting model, that mimics the glucose-induced electrical activity of pancreatic beta-cells (Deng, 1993). To serve to this purpose, we use a technique developed to find analytic approximate solutions for strongly nonlinear problems. This analytical algorithm involves an auxiliary parameter which provides us with an efficient way to ensure the rapid and accurate convergence to the exact solution of the bursting model. By using the homotopy solution, we investigate the dynamical effect of a biologically meaningful bifurcation parameter rho, which increases with the glucose concentration. Our analytical results are found to be in excellent agreement with the numerical ones. This work provides an illustration of how our understanding of biophysically motivated models can be directly enhanced by the application of a newly analytic method.
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Introduction: Visceral leishmaniasis is an endemic protozoan found in Brazil. It is characterized by fever, pallor, hepatosplenomegaly, lymphadenopathy, and progressive weakness in the patient. It may lead to death if untreated. The drug of choice for treatment is meglumine antimoniate (Glucantime®). The aim of this study was to evaluate patients with visceral leishmaniasis according to criteria used for diagnosis, possible reactions to Glucantime® and blood pressure measured before and after treatment. Methods: 89 patients admitted to the Teaching Hospital Dr. Hélvio Auto (HEHA) in Maceió-AL, in the period from May 2006 to December 2009 were evaluated. Data were collected on age, sex, origin, method of diagnosis, adverse effects of drugs, duration of hospitalization, duration of treatment and dosage up to the onset of adverse effects. Results: There was a predominance of child male patients, aged between one and five years old, from the interior of the State of Alagoas. Parasitological diagnosis was made by bone marrow aspirate; three (3.37%) patients died, 12 (13.48%) had adverse reactions and treatment was changed to amphotericin B, and 74 (83.14%) were cured. Changes that led to replacing Glucantime® were persistent fever, jaundice, rash, bleeding and cyanosis. Conclusion: During the study, 89 patients hospitalized for VL were analyzed: 74 were healed, 12 were replaced by amphotericin B treatment and three died. Most of them were under five years old, male and came from the interior. The dosage and duration of treatment with Glucantime® were consistent with that advocated by the Ministry of Health. Persistence of fever, jaundice, rash, cyanosis and bleeding were the reactions that led the physician to modify treatment. No change was observed in blood pressure before and after treatment. This study demonstrated the work of a hospital, a reference in the treatment of leishmaniasis, which has many patients demanding its services in this area. It demonstrates that this disease is still important today, and needs to be addressed properly to prevent injury and death due to the disease.
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Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores
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Publicado em "AIP Conference Proceedings", Vol. 1648