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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Isolement et caractérisation des saponosides de trois plantes de la famille des araliaceae et dracaenaceae et évaluation de leurs activités cytotoxiques sur cellules tumorales / Isolation and caracterisation of saponins from three plants of Araliaceae and Dracaenaceae families and evaluation of their cytotoxic activities on tumoral cells

Kougan Nkwokap, Guy Beddos 20 September 2010 (has links)
L’intérêt des substances d’origine naturelle, potentiellement anti-tumorales nous a amené à nous intéresser aux saponines triterpéniques et stéroïdiques de plantes issues de la biodiversité africaine de la famille des Araliaceae et des Dracaenaceae. En effet, des études antérieures menées sur quelques plantes de ces deux familles ont conduit à l’obtention de molécules complexes et originales possédant d’excellentes propriétés cytotoxiques, immuno-modulatrices, anti-inflammatoires. Au vu de ces résultats nous avons entrepris des investigations pharmaco-chimiques sur Cussonia arborea (Araliaceae), Dracaena deisteliana et Dracaena arborea (Dracaenaceae), plantes médicinales couramment utilisées en pharmacopée traditionnelle africaine pour traiter différentes maladies. Les travaux menés ont conduit à l’isolement de 31 composés purs en utilisant les différentes techniques analytiques du laboratoire notamment les diverses techniques de chromatographie liquide successive à pression atmosphérique, moyenne pression et flash chromatographie sur silice en phase normale et en phase inverse. Les structures ont été déterminées par les méthodes de spectrométrie de masse en source FAB et de spectroscopie de RMN 1D et 2D (COSY, TOCSY, NOESY, HMBC et HSQC). Parmi les 07 composés purs obtenus des écorces de Cussonia arborea, 5 sont des nouvelles saponines triterpéniques dont un dérivé de l’acide ursolique, un dérivé de l’hédéragénine et trois dérivés de l’acide oléanolique, tous disubstitués en position 3 et 28 par des chaînes oligosaccharidiques. 13 composés purs sont obtenus à partir des feuilles de Cussonia arborea, dont 7 nouvelles saponines triterpéniques dérivés de l’acide ursolique, de l’acide 23-hydroxyursolique, de l’hédéragénine et de l’acide oléanolique dont 04 d’entre elles sont obtenues sous forme de mélanges inséparables d’isomères acide oléanolique/acide ursolique et hédéragénine/acide 23-hydroxyursolique. A partir des écorces de Dracaena arborea et des tiges de Dracaena deisteliana, nous avons isolé et caractérisé 10 saponines stéroïdiques dont 4 nouvelles et une sapogénine. Les activités de certains de ces produits purs ont été évaluées sur deux lignées de cellules cancéreuses coliques humaines HCT 116 et HT-29. / The interest of the substances from natural origin, potentially antitumor led us to interest in triterpenoid and steroidal saponins of plants from the African biodiversity belonging to the Araliaceae and Dracaenaceae families of plants. Indeed, of the former studies undertaken on some plants of these two families led to obtaining complex and original molecules having excellent cytotoxic, immuno-modulating, anti-inflammatory properties. Within sight of these results we undertook pharmaco-chemical investigations on Cussonia arborea (Araliaceae), Dracaena deisteliana, and Dracaena arborea (Dracaenaceae), medicinal plants usually used in african traditional pharmacopeia to treat various diseases. The work led to the isolation of 31 pure compounds by using the various analytical techniques in particular the various chromatography techniques (CC, MPLC, TLC, flash) on silica gel, normal and reversed phases. The structures were determined by the methods of mass spectrometry (FAB, ESI, IE) and 1D (1H and 13C) and 2D (COSY, TOCSY, NOESY, HMBC and HSQC) NMR spectroscopy. Among the 07 pure compounds obtained of the barks of Cussonia arborea, 5 are new triterpenoid saponins derivatives of ursolic acid, hederagenin and three derived from the acid oleanolic, all disubstituted in position 3 and 28 by oligosaccharidic chains. 13 pure compounds were obtained from leaves of Cussonia arborea, seven of which are new triterpenoid saponins derivatives of oleanolic acid, ursolic acid, hederagenin and 23-hydroxyursolic acid of which four were obtained as mixtures of isomers oleanolic acid/ursolic acid and hederagenin/23-hydroxyursolic acid. From the bark of Dracaena arborea and stem of Dracaena deisteliana, we isolated and characterized ten steroidal saponins including 4 new and sapogenin. The activities of some of these pure products were evaluated on two cancerous lines human colic cells HCT 116 and HT-29.
122

Preconcentration strategies in capillary electrophoresis for the determination of pharmaceutical and personal care products

Maijó Ferré, Irene 17 July 2012 (has links)
L'objectiu principal d'aquestaTesi Doctoral és el desenvolupament de diferents estratègies per disminuir els límits de detecció de l’electroforesicapil•lar per a la determinació de compostos farmacèutics i els productes de cura personal. Aquestes estratègies es basen en les tècniques de preconcentració electroforètiques i cromatogràfiques, i l'ús de l’espectrometria de masses com a sistema de detecció. Com a tècniques de preconcentració electroforètiques s'han estudiat les tècniques de samplestacking i sweeping, i com a tècnica de preconcentració cromatogràficas’ha avaluat l'acoblament en línia entre l'extracció en fase sòlida i l'electroforesicapil•lar (In-line SPE-CE). Entre elsPPCPs, aquesta tesi doctoral es centra específicament en els antiinflamatoris no esteroïdals(AINE), els parabens i els filtres ultraviolats. Un altre dels objectius d'aquestaTesi Doctoral és estudiarl’aplicabilitat de les metodologies desenvolupades per a l'anàlisi de mostres ambientals per determinar PPCP. / The main objective of this Doctoral Thesis is the development of different strategies to decrease the detection limits of capillary electrophoresis for the determination of pharmaceutical and personal care products. These strategies are based on electrophoretic and chromatographic preconcentration techniques, and the use of mass spectrometry as a detection system. The electrophoretic preconcentration techniques studied included sample stacking techniques and sweeping while the chromatographic preconcentration technique evaluated was in-line coupling between solid phase extraction and capillary electrophoresis. With respect to PPCPs, this Doctoral Thesis focuses specifically on non-steroidal anti-inflammatory drugs (NSAIDs), parabens and UV-filters. Another objective of this Doctoral Thesis is to study the suitability of the developed methodologies for the determination of PPCPs in environmental samples.
123

Farmakoterapie bolestí hlavy u dospělých / Pharmacotherapy of headaches in adults

Holinská, Eliška January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Eliška Holinská Supervisor: Prof. MUDr. Radomír Hrdina, CSc. Title of diploma thesis: Pharmacoteraphy of headache in adults Headache is one of the most common health problem that encounters almost everyone during the life. Depending on the cause, headaches can be divided on the primary headaches, which are the subject of the diploma thesis, and secondary headaches, which are caused by other diseases. The primary headaches are migraine, tension-type headache, cluster headache and primary chronic daily headache. Headache is not a life-threating condition but it can significantly reduce the quality of life, particularly the chronic forms of headache. The determination of the right diagnosis is essential for the choice of appropriate therapy. For primary headache are typical negative test results, there are no structural lesions or signs of organic brain damage. Diagnostics is comlicated and it is primarily based on a carefully processed medical history. In the therapy of primary headache are used both pharmacological and non-pharmacological methods, optimaly in combination. Pharmacological treatment consists of preventive and acute therapy. The preventive treatment is given to reduce the...
124

Vliv hyaluronanu na transdermální penetraci vybraných léčivých látek / Hyaluronan effect on transdermal penetration of selected pharmaceutical substances

Ureš, Tomáš January 2014 (has links)
This work deals with the transmittance of a family of non-steroidal anti-inflammatory drugs across biological membranes in combination with the use of hyaluronan. Hyaluronic acid (hyaluronan, HYA) is a linear polysaccharide formed from disacharide units containing N-acetyl-D-glucosamine and glucuronic acid. HYA is present in almost all biological fluids and tissues, so there is an assumption that could affect the penetration of substances through the skin. Standards were prepared by anti-inflammatory drugs in admixture with various concentrations hyaluronan and subsequently measured transmittance of such substances through the skin. Standards were applied to the skin obtained from pig auricle. The drug content was determined by HPLC.
125

Chemoprevention of Colorectal Cancer

Krishnan, K, Brenner, D E. 01 December 1996 (has links)
This review summarizes the principles of cancer chemoprevention and discusses the evidence from epidemiologic and experimental studies and preclinical and clinical trials of potential colorectal chemopreventive agents. The putative mechanisms of action of the drugs in chemoprevention and their potential to reduce the incidence and mortality rate of colorectal neoplasms are discussed. The future of colorectal chemoprevention will depend on important new insights into molecular carcinogenesis of colorectal cancer, application of molecular markers as surrogate endpoints, and ultimately on therapeutic targets of prevention in clinical trials.
126

Ketoprofen Tissue Permeation in Swine Following Cathodic Iontophoresis

Panus, Peter C., Ferslew, K E., Tober-Meyer, B, Kao, R. L. 01 January 1999 (has links)
BACKGROUND AND PURPOSE: Pharmacokinetic assessment of drug tissue permeation following iontophoresis is limited. The depth of ketoprofen tissue permeation following cathodic iontophoresis (4 mA, 40 minutes) and the stereoselectivity of drug delivery were examined in this study. SUBJECTS: Ketoprofen (750 mg) was iontophoresed onto one porcine medial thigh, with passive drug permeation conducted on the other thigh. METHODS: Skin, subcutaneous fascia, and muscle biopsies from the drug delivery sites were harvested and stored separately, and the "R" and "S" ketoprofen enantiomers were determined. Results. Iontophoretic and passive applications yielded equivalent total ketoprofen concentrations in the skin and fascia. In contrast, multivariate analysis demonstrated that the ketoprofen concentration in the first centimeter of muscle following iontophoresis was greater than the drug concentration in the deeper underlying muscle layers and greater than that delivered to any muscle layer following passive delivery. No transcutaneous stereoselective delivery) of ketoprofen was detected. CONCLUSION AND DISCUSSION: Compared with passive delivery, iontophoresis enhances nonstereoselective ketoprofen permeation into the fascia-muscle interface. With delivery to deeper tissue sites, however, there is no apparent enhancement over passive application.
127

Nové regulační mechanismy nukleace mikrotubulů / New regulatory mechanisms of microtubule nucleation

Černohorská, Markéta January 2016 (has links)
MT nucleation from γ-tubulin complexes, located at centrosome, is an essential step in the formation of MT cytoskeleton. In mammalian cells, -tubulin is encoded by two genes. We functionally characterized two γ-tubulin proteins and have found that both are functionally equivalent. γ-Tubulin 2 is able to substitute for γ-tubulin 1 in MT nucleation. However, we revealed that unlike TUBG1, TUBG2 expression is downregulated in mouse preimplantation development. Mast cells represent effectors of the allergy reaction. Their activation by antigen induces number of cellular processes such as degranulation, proliferation and cytoskeleton rearrangements. The regulatory mechanisms of MT reorganization during mast cell activation are unknown. We identified new signaling proteins, GIT1 and PIX that interact with - tubulin. Depletion of GIT1 or PIX leads to changes in MT nucleation. GIT1 is phosphorylated on tyrosine and associates with γ-tubulin in a Ca2+ -dependent manner. Our data suggested a novel signaling pathway for MT rearrangement in mast cells where tyrosine kinase-activated GIT1 and βPIX work in concert with Ca2+ signaling to regulate MT nucleation. We tested the capability of GIT1 and PIX to influence -tubulin function in more cell types. We found out that GIT1/βPIX signaling proteins together...
128

Validação do Teste de ativação de basófilos no diagnóstico de reações de hipersensibilidade a anti-inflamatórios não esteroidais / Validation of basophil activation test for the diagnosis of hypersensitivity reactions to nonsteroidal antiinflammatory drugs

Misumi, Denise Shimbo 10 May 2013 (has links)
Introdução: Atualmente, o diagnóstico das reações de hipersensibilidade a anti-inflamatórios não esteroidais (AINEs) baseia-se na história relatada pelo paciente e, em determinados casos, é realizado o Teste de Provocação. Todavia, este teste pode expor os pacientes a riscos graves, inclusive anafilaxia. Em busca de ferramenta mais segura, tem-se estudado o Teste de Ativação de Basófilos (BAT). Trata-se de um teste in vitro, no qual é possível testar diversos estímulos em uma única amostra de sangue, avaliando a ativação dos basófilos (indicativo de reação de hipersensibilidade), através do aumento da expressão de moléculas na superfície desses leucócitos, como o CD63. Objetivo: Padronizar e validar o BAT para ácido acetilsalicílico (AAS), diclofenaco, dipirona e paracetamol em pacientes com hipersensibilidade a AINEs. Metodologia: Participaram 20 (testados com os quatro AINEs) + 33 (testados somente com AAS) pacientes atendidos no Serviço de Imunologia Clínica e Alergia do HCFMUSP, que apresentaram manifestações cutâneas em até 24 horas após exposição a um ou múltiplos AINEs, bem como 13 (quatro AINEs) + 26 (AAS) controles. A técnica consistiu em incubar sangue total com os AINEs já mencionados e, depois, marcar as amostras com anticorpos monoclonais (CD45, anti-IgE e CD63) para posterior leitura por citometria de fluxo. Os resultados obtidos foram comparados com as histórias clínicas e os testes de provocação oral, quando realizados. Resultados: Utilizando os critérios de positividade do BAT empregados na literatura (isto é, porcentagem de CD45+IgE+highCD63+ e índice de estimulação), a sensibilidade e a especificidade variaram de acordo com o AINE: para ácido acetilsalicílico foram 75,0% e 16,7%, respectivamente, diclofenaco, 100% e 0%, dipirona, 23,5% e 66,7%, paracetamol, 40,0% e 42,9%. Após a realização de curvas dose-resposta e tempo-resposta somente com AAS, foi encontrado novo critério de positividade: média de intensidade de fluorescência (MFI) menor do que 6575 representava BAT positivo; com isso, os valores de sensibilidade e especificidade foram: 84,4% e 34,6%, respectivamente. O BAT foi mais sensível em pacientes cuja última reação ocorreu há menos de um ano da data de execução do BAT (93,7%). Conclusão: Devido aos baixos valores de sensibilidade e/ou especificidade, não foi possível padronizar e, por conseguinte, validar o BAT para ácido acetilsalicílico, diclofenaco, dipirona e paracetamol. / Introduction: Currently, the diagnosis of nonsteroidal antiinflammatory drugs (NSAIDs) hypersensivitity is based on patients´ clinical history and drug provocation tests, which are done in selected cases. Nevertheless, this test may expose patients to severe risks, including anaphylaxis. Looking for a safer tool, Basophil Activation Test (BAT) for allergy diagnosis has been studied in the last years. It is an in vitro method where a wide variety of stimuli can be tested, incubating them with the patient\'s blood sample, and observing basophil activation (indication of hypersensitivity) through upregulation of CD63 (or other basophil activation markers) on this leucocyte\'s membrane. Objective: To standardize and validate BAT stimulated with acetylsalicylic acid (ASA), diclophenac, dipyrone and paracetamol in NSAID hypersensitive patients. Methods: Patients which reported immediate reactions (less than 24 hours) after exposure to one or multiple NSAIDs, with cutaneous symptoms were enrolled from Clinical Immunology and Allergy outpatient clinic from HC-FMUSP. BAT with the four NSAIDs was tested on 20 patients and 13 controls and BAT with ASA only, on 33 patients and 26 controls. BAT consisted of incubating whole blood with NSAIDs, then triple-labeled with monoclonal antibodies (CD45, anti-IgE, CD63) for analysis by flow cytometry. BAT results were compared to clinical history and oral provocation tests, when available. Results: According to literature\'s positivity criteria (percentage of CD45+IgE+highCD63+ and stimulation index), sensitivity and specificity varied according to the NSAID tested: for ASA was 75.0% and 16.7% respectively, diclophenac, 100.0% and 0.0%, dipyrone, 23.5% and 66.7%, paracetamol, 40.0% and 42.9%. A new positivity criterion was possible to be defined after further dose-response and time-response curves only for ASA: Mean Fluorescence Intensity lower than 6575 (positive BAT). Accordingly, new sensitivity and specificity for BAT in ASA hypersensitivity were 84,4% and 34,6%. Patients that presented the last reaction in the last year were more likely to present a positive BAT (93.7%). Conclusion: Due to low values for sensitivity and/or specificity, it was not possible to standardize and validate BAT for ASA, diclophenac, dipyrone and paracetamol.
129

Analgesia preemptiva do cetoprofeno e do parecoxibe em cirurgia para remoção de terceiros molares inclusos / Preemptive analgesia of the ketoprofen and parecoxib in the surgery to removal of impacted third molar teeth

Arantes, Viviana Moraes Neder 03 October 2006 (has links)
Este trabalho prospectivo, duplo-cego randomizado, avaliou o efeito da analgesia preemptiva do cetoprofeno e do parecoxibe. Sessenta pacientes foram submetidos à cirurgia para remoção de terceiros molares inferiores bilaterais inclusos, sendo operado um lado de cada vez. O paciente foi seu próprio controle. Os pacientes foram separados em dois grupos de 30 pacientes. No grupo parecoxibe, na primeira operação foi usado o parecoxibe ou placebo, endovenoso, 30 minutos antes da cirurgia e imediatamente após a operação foi feita a administração do placebo ou parecoxibe, garantindo ao paciente receber parecoxibe antes ou após a operação. O lado oposto foi operado após duas semanas da primeira cirurgia e o paciente que havia recebido parecoxibe antes e placebo depois da operação recebeu placebo antes e parecoxibe depois da operação e o que havia recebido placebo antes e parecoxibe depois recebeu parecoxibe antes e placebo depois. Nos 30 pacientes do grupo cetoprofeno, o modelo foi o mesmo, substituindo-se apenas o parecoxibe pelo cetoprofeno. O paciente pôde utilizar como medicação resgate a dipirona, sempre que necessário para controlar a dor pós-operatória. Após a operação foi fornecido para todos os pacientes um questionário, contendo a escala analógica visual (EAV), a escala descritiva de dor (EDD) e uma tabela para informar o consumo de medicação resgate. Foi avaliada a dor pós-operatória por meio da EAV, da EDD e pelo consumo de medicação resgate. Não houve diferença estatisticamente relevante quanto a intensidade da dor com o uso do parecoxibe ou do cetoprofeno antes ou depois do procedimento cirúrgico. Ao comparar a analgesia proporcionada pelo cetoprofeno e pelo parecoxibe os resultados mostraram que o parecoxibe administrado antes do procedimento cirúrgico foi mais eficaz do que o cetoprofeno no controle da dor na quarta hora do pós-operatório (p=0,041), mas foi menos eficaz após 24h (p=0,003). Quando se comparou a analgesia proporcionada por esses fármacos usados após a operação, o parecoxibe foi mais eficaz do que o cetoprofeno após 6 e 8h do procedimento (p=0,003 e 0,023, respectivamente). / This is a prospective, double-blind randomized, cross over experiment, to evaluate the effect of the preemptive analgesia of ketoprofen and parecoxib. Sixity patients who had gone though surgery for removal of the impacted mandibular bilateral third molar teeth, having one side operated each time, were evaluated. The patients were separated in groups of 30, in the parecoxib group (P). On the first operation parecoxib or placebo were used 30 minutes before the surgery. Immediately after the operation, placebo or parecoxib were administred, so that the patient who had received parecoxib before the operation or after it. The opposite side was operated two weeks after the first surgery and the patients who received parecoxib before and placebo after operation received placebo before and parecoxib after operation and patients who received placebo before and parecoxib after received parecoxib before and placebo after, under the same method. In the group C (n= 30), the model was the same, using ketoprofen instead parecoxib. The patient could use dipyrone as rescue medication, in the event of postoperative pain. A questionnaire was provided to the patient after each surgery, containing a visual analogic scale, a descriptive pain scale and a table to inform the consum of rescue medication. The postoperative pain was evaluated by visual analogic scale, descriptive pain scale and rescue medicine consum. There was no statistically relevant difference as pain intensity with use of parecoxib or ketoprofen before or after the surgical procedure. Comparing ketoprofen analgesia against parecoxib analgesial, the results shown that the administration of parecoxib before the surgical procedure had a major efficacy than ketoprofen in pain control by the fourth hour post operatory (p=0,041), but was less efficient after 24 hours (p=0,003). When comparing the analgesic effect of both drugs after the operation, parecoxib was more effective than ketoprofen six and eight hours after the procedure (p=0,003 and 0,023, respectively).
130

Estudo físico-químico da sorção de diclofenaco em resina colestiramina / Physical-chemical study of the sorption of diclofenac onto cholestyramine resin

Ramos, Ingrid Graça 19 December 2007 (has links)
Os seguintes parâmetros foram investigados para a síntese do resinato de diclofenaco colestiramina: sal precursor, concentração inicial, tempo de contato, velocidade de agitação e temperatura. Dos estudos de equilíbrio, foi verificado que os íons diclofenaco foram sorvidos em dois tipos de sítios diferentes da resina e puderam ser adequadamente representados pela soma de dois termos, derivado do modelo de Boyd, para quimissorção, e Langmuir, para fisissorção. Os dados cinéticos foram ajustados pelos modelos de: pseudo-primeira ordem, pseudo-segunda ordem e difusão intrapartícula. O modelo de pseudo-segunda ordem ajustou-se aos dados experimentais para todo o período de sorção com alto coeficiente de correlação linear. Equações foram desenvolvidas a partir do modelo de pseudo-segunda ordem e puderam predizer a quantidade de íons diclofenaco sorvida em qualquer tempo para a concentração inicial de 7,5 g.L-1. Os resultados dos parâmetros termodinâmicos sugeriram que o processo de sorção é resultante de difusão e reação química em relação à temperatura. / The following parameters were investigated for the synthesis of diclofenac-cholestyramine resinate: diclofenac salt precursor, initial diclofenac concentration, contact time, stirring speed and temperature. From equilibrium studies was verified that the diclofenac ions were adsorbed on two different sites of the resin and may be adequately represented by the sum of two terms, derived from the Boyd model, for chemisorption, and Langmuir, for physisorption. The kinetic data were fitted to the pseudo-first, pseudo-second and intraparticle diffusion models. The pseudo-second order model was found to fit the experimental data for the entire sorption period with high coefficient of determination. Equations were developed using pseudo-second order model and could predict the amounts of diclofenac ions adsorbed at any contact time for the initial concentration of 7,5 g.L-1. The results of thermodynamic parameters suggest that the sorption process results for both diffusion and chemical bonding processes in relation to the temperature.

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