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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

Development of a high pressure liquid chromatographic method for the simultaneous analysis of sulphamethoxazole and trimethoprim and its application to biological fluids and dissolution rate studies on solid oral dosage forms

Gochin, Rosa January 1980 (has links)
Co-trimoxazole, a combination of a 5-to-l ratio of Sulphamethoxazole (SMZ) and Trimethoprim (TMP) , is a highly effective, broad-spectrum antibacterial agent. Since its introduction in 1968, it has been extensively used in infections of the respiratory and urinary tracts. Co-trimoxazole was developed by the systematic investigation of a series of compounds whose mechanism of action was already known. As early as 1950 synergy between sulphonamides and 2,4-diaminopyrimidines was reported. This was to be expected as both groups of drugs exert their antibacterial activity by interfering with the same biochemical pathway in bacteria. TMP was chosen from among many 2,4-diaminopyrimidines tested because of its good antibacterial activity and low toxicity. SMZ was chosen from the sulphonamides available for combination with TMP because of similarity of their biological half-lives. The widespread use of the combination coupled with the fact that monitoring of the levels of all drugs in the body is becoming increasingly important has stimulated research into rapid and efficient methods for the analysis of TMP and SMZ in biological fluids. Another consequence of the immense popularity of the combination is the appearance on the market of several generic preparations of Co-trimoxazole. It is now generally recognized that drug products from different manufacturers which are chemically equivalent may not be therapeutically equivalent. This is due to the fact that the absorption rate and/or bioavailability (extent of absorption) of a poorly soluble drug may be markedly affected by its release rate from the product and by its subsequent dissolution rate in gastrointestinal fluids. Hence bioequivalence of these various products should be established
122

Development and assessment of azithromycin paediatric suppository formulations

Mollel, Happiness January 2006 (has links)
The use of the oral route of administration for the treatment of young children with antibiotics can at times be problematic since, factors such as nausea, vomiting, taste and/or smell, in addition to the challenges associated with the administration of suspensions, may contribute to poor patient compliance. In such cases, the use of the rectal route of administration may be appropriate. Therefore, suppositories containing 250 mg azithromycin (AZI) were manufactured and assessed for potential as an antibiotic suppository dosage form. Suppositories, containing AZI dihydrate were manufactured by the fusion method, using different grades of PEG, Witepsol® and Suppocire® bases. The rate and extent of AZI release was evaluated using USP apparatus I, and samples were analyzed using a validated HPLC method. Differences in the rate and extent of AZI release were observed with the greatest amount of AZI being released from PEG formulations. The rate and extent of AZI release from formulations manufactured using fatty bases were influenced by physicochemical properties, such as melting rate and hydroxyl value, of the bases. In addition drug partitioning appeared to favor the lipid phase and had a negative impact on AZI release characteristics. Two different formulation approaches were used in an attempt to increase the rate and extent of AZI release from fatty base formulations. The use of surfactants significantly increased AZI release from formulations manufactured with fatty bases with high hydroxyl values. The use of urea or Povidone K25 in combination with AZI as a physical mixture or solid dispersion did not increase the rate and extent of AZI release from the fatty suppositories, to any significant extent. The mechanism of drug release was evaluated using several mathematical models, including the Higuchi, Korsmeyer- eppas, Zero and, First order models. In addition, in vitro dissolution profiles were characterized by the difference and similarity factors, f1 and f2 and by use of the Gohel similarity factor, Sd. AZI release kinetics were best described by the Higuchi and Korsmeyer-Peppas models and the values of the release exponent, n, revealed that drug release was a consequence of the combined effects of AZI diffusion, rate of melting of the base and partitioning of the drug which can be considered to be anomalous release.
123

Farmacomagnetografia colônia: estudo in vitro da desintegração de comprimidos magnéticos revestidos

Andreis, Uilian de [UNESP] 21 December 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-21Bitstream added on 2014-06-13T21:03:25Z : No. of bitstreams: 1 andreis_u_dr_botib.pdf: 1982280 bytes, checksum: 3d2499c3ae7d16a4f3593d5077238d10 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A avaliação dos parâmetros motores do trato gastrintestinal é condição necessária para caracterizar o comportamento de formas farmacêuticas sólidas administradas pela via oral. A função motora gastrintestinal pode ser alterada em detrimento de doenças, interações com medicamentos ou intervenções cirúrgicas. Essas alterações, por sua vez, podem influenciar diversos processos farmacêuticos e, consequentemente, a biodisponibilidade dos fármacos. Comprimidos são as formas farmacêuticas mais utilizadas na terapia. Para garantir a eficácia e segurança dessas preparações, são necessários testes in vitro que simulam o trato gastrintestinal. Entretanto, não é possível estimar com precisão a influencia dos parâmetros gastrintestinais na liberação do fármaco. Por essa razão, os ensaios in vivo realizados por técnicas não invasivas e inócuas ao indivíduo são necessários, pois permitem monitorar simultaneamente os parâmetros motores e suas interrelações com os processos de liberação e biodisponibilidade dos fármacos. O objetivo desse trabalho foi empregar a técnica de Biosusceptometria AC associada à farmacocinética para avaliar a influência da motilidade gastrintestinal, bem como das alterações induzidas nessa função pela administração prévia de um procinético (Domperidona) e um antimuscarínico (Butilbrometo de Escopolamina). Além disso, foram avaliadas as influências desses parâmetros no processo de liberação e biodisponibilidade de um fármaco modelo (Diclofenaco Sódico) adicionado a comprimidos revestidos / The evaluation of gastrointestinal motor parameters is necessary towards characterize the behavior of solid dosage forms orally administered. The gastrointestinal motor function may be altered by diseases, drugs or surgery. These alterations may influence a number of pharmaceutical processes and consequently the bioavailability of drugs. Tablets are the dosage forms most commonly used in therapy. To ensure the efficacy and safety of these formulations, in vitro tests in simulated gastrointestinal conditions are needed. However, such conditions as well as the influence of gastrointestinal parameters on drug release cannot be fully predicted. For these reasons, in vivo studies are realized by noninvasive and harmless techniques, since they allows monitoring gastrointestinal motor parameters and the relationships with drug delivery and bioavailability. The aim of this work was to employ the AC Biosusceptometry to evaluate the influence of gastrointestinal motility as well as the induced changes on this function by previous administration of a prokinetic drug (domperidone) and an antimuscarinic agent (scopolamine butilbromide). In addition, it have been evaluated how these alterations influenced the drug release and bioavailability of a model drug (sodium diclofenac) added to coated tablets
124

A biosusceptometria AC aplicada à tecnologia farmacêutica

Corá, Luciana Aparecida [UNESP] 18 September 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-18Bitstream added on 2014-06-13T20:03:09Z : No. of bitstreams: 1 cora_la_dr_botib.pdf: 5114466 bytes, checksum: ae97ba77c87f4a9ec255be22db0f2b7f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A administração oral de drogas é uma prática comum na terapia e as formas farmacêuticas sólidas são amplamente utilizadas. A variação no perfil de absorção ao longo do trato gastrintestinal (TGI) humano e a possibilidade de liberar drogas em diferentes regiões são os maiores desafios para o desenvolvimento de novos produtos. Desse modo, avaliar formas farmacêuticas sólidas in vivo fornece um entendimento mais profundo quando um efeito sistêmico ou local é desejado. Geralmente, estes estudos são realizados por meio da cintilografia e técnicas biomagnéticas. A Biosusceptometria de Corrente Alternada (BAC) é uma técnica que merece destaque por suas características, acurácia dos resultados obtidos e versatilidade. A BAC propiciou imagens do processo de desintegração de comprimidos tanto in vitro quanto no estômago humano, introduzindo outra perspectiva na análise desse processo. Os resultados também foram correlacionados com sucesso com aqueles obtidos por metodologias específicas, garantindo uma análise mais acurada dos parâmetros físicos envolvidos com a desintegração de comprimidos. A utilização da BAC permitiu avaliar a motilidade gastrintestinal e o processo de desintegração de cápsulas de hidroxipropilmetilcelulose (HPMC) revestidas no cólon humano. Além disso, também foi possível investigar a influência do estado prandial no esvaziamento gástrico e no trânsito gastrintestinal de um sistema multiparticulado magnético. Todos esses trabalhos fortaleceram a BAC como um método alternativo na pesquisa farmacêutica demonstrando seu potencial para avaliar diferentes processos, apesar das suas limitações. Sintetizando, a BAC é uma ferramenta valiosa, com a vantagem de ser livre de radiação e inócua aos voluntários, e vasta aplicabilidade na pesquisa farmacêutica, farmacológica e fisiológica. / Oral administration is widely accepted route for drug delivery and solid dosage forms are commonly administered. The variation of absorption profiles along the human gastrointestinal tract (GIT) and the ability to target drugs by adequate dosage forms to distinct sites is the challenge in the pharmaceutical development of solid dosage forms. An understanding of the factors involved in drug absorption and how the gastrointestinal variables can interfere with this process is important to develop more reliable drug delivery systems. The performance of pharmaceutical dosage forms must be fully investigated in vivo to provide more reliable information when a local or systemic effect is desirable. Generally, in vivo investigation on the behavior of dosage forms has been made by using gamma‐scintigraphy and biomagnetic techniques. AC Biosusceptometry (ACB) deserves consideration due to its features, accuracy and versatility. By using ACB technique, it was possible to monitor the disintegration process through acquisition of magnetic images in vitro and in human stomach. The results also were successfully correlated with those obtained with standard methods which provided a more reliable analysis on the physical parameters involved in the disintegration process of tablets. ACB allowed evaluating the gastrointestinal motility and the disintegration of hydroxipropylmethylcellulose (HPMC) coated capsules in human colon. Moreover, it was possible to investigate the gastric emptying and gastrointestinal transit of a magnetic multiparticulate system under influence of prandial state. All these studies have contributed to establish the ACB as an alternative method for pharmaceutical research and, despite some limitations, it was feasible to evaluate different pharmaceutical processes. In summary, ACB is a radiation free and non‐invasive technique with wide applicability in pharmaceutical, physiological and pharmacological researches.
125

Avaliação da dose de radiação absorvida em exames radiológicos durante o planejamento radioterápico

Camargo, Rafaela Ferraz de [UNESP] 18 March 2014 (has links) (PDF)
Made available in DSpace on 2015-01-26T13:21:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-18Bitstream added on 2015-01-26T13:30:40Z : No. of bitstreams: 1 000794951.pdf: 1115711 bytes, checksum: 4c1e59b3111229911b6794fde269fab1 (MD5) / A radioterapia é uma modalidade médica que emprega radiações ionizantes para o tratamento de doenças. O sucesso da terapêutica depende de vários fatores, dentre eles a liberação precisa da dose de radiação no volume tumoral e a perfeita reprodutibilidade diária das orientações prescritas na ficha técnica do paciente. A delimitação do campo de radiação, o qual deve abranger todo o tumor e permitir uma margem de segurança que considere a movimentação anatômica, é feita durante os procedimentos de planejamento radioterápico. Nesta etapa do tratamento, o médico radioterapeuta, auxiliado pelo físico médico e o tecnólogo em radiologia, utiliza técnicas radiográficas através de um sistema de escopia para visualização do volume alvo de irradiação, e realiza imagens radiográficas estáticas para documentação do caso clínico. Na rotina dos procedimentos de planejamento radioterápico, normalmente não é feita a quantificação da dose de radiação liberada no procedimento, devido principalmente à grande e exaustiva agenda de atividades dos profissionais envolvidos. Neste trabalho foi avaliada a dose de radiação liberada em exames radiológicos realizados durante o planejamento radioterápico, avaliando a influência desta dose no total de exposições em que o paciente foi submetido durante todo o curso da radioterapia. A pesquisa consistiu no acompanhamento dos procedimentos de planejamento radioterápico executadas no Serviço Técnico de Radioterapia da Faculdade de Medicina da UNESP de Botucatu, extraindo os valores das técnicas radiográficas empregas para diferentes planejamentos. Após a caracterização individualizada do planejamento, as técnicas radiográficas utilizadas em cada um dos casos clínicos, foram repetidas e as doses de radiação liberadas no procedimento foram quantificadas por meio de detectores de radiação específicos e calibrados para a energia dos raios-x de ... / Radiotherapy is a medical modality that uses ionizing radiation for the treatment of diseases. The treatment success depends on several factors, including the precise release of the radiation dose in the tumor volume and the perfect daily reproducibility of the guidelines prescribed in the technical sheet of the patient. The delimitation of the radiation field, which should cover the entire tumor and allow a safety margin that considers the anatomical movement, is taken during the procedures of the radiotherapy planning. At this stage of treatment, the radiotherapist physician, aided by the medical physicist and the technologist in radiology, utilizes radiographic techniques through a system of scopy to visualize the target volume of irradiation, and performs static radiographic images to document the clinical case. In the routine of the radiotherapy planning procedures, usually is not performed the quantification of the radiation dose released in the procedure, mainly due to the large and exhaustive schedule of activities of the professionals involved. In this study, was assessed the radiation dose released in radiological examinations performed during the radiotherapy planning, evaluating the influence of this dose in the exposures total in which the patient has undergone throughout the radiotherapeutic procedure. The research consisted in monitoring the radiotherapy planning procedures performed at UNESP, “Serviço Técnico de Radioterapia” of “Faculdade de Medicina de Botucatu”, extracting the radiographic technique values used for different plannings. After the individualized characterization of the plannning, the radiographic techniques used in each clinical case, were repeated and the radiation doses released in the procedure were quantified by specific radiation detectors and they were calibrated to the energy of the simulation x-ray. It is concluded that the absorbed radiation dose, which ...
126

Idealizações de um programa baseado em redes neurais para dosagem de concreto / Idealizations of a program based on neural networks for concrete strength

Bolognini, Enio José [UNESP] 02 September 2016 (has links)
Submitted by ENIO JOSÉ BOLOGNINI null (ejbolognini@gmail.com) on 2016-10-31T18:28:26Z No. of bitstreams: 1 DISSERTAÇÃO FINAL CORRIGIDA.pdf: 5151071 bytes, checksum: 5ee75ea3a591ae39228c7aaf567a29bc (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-11-08T11:31:17Z (GMT) No. of bitstreams: 1 bolognini_ej_me_ilha.pdf: 4791439 bytes, checksum: fdf2bbe8d623111701e126b75d7a4fbd (MD5) / Made available in DSpace on 2016-11-08T11:31:17Z (GMT). No. of bitstreams: 1 bolognini_ej_me_ilha.pdf: 4791439 bytes, checksum: fdf2bbe8d623111701e126b75d7a4fbd (MD5) Previous issue date: 2016-09-02 / A produção de concreto está cada vez mais exigente. Medidas de prevenção e correção são empregadas na dosagem do concreto, gerando lucros e economia no preparo. A fim de obter economia e praticidade na dosagem de concretos, neste estudo foi desenvolvido, após a coleta de dados experimentais, a criação de rede neural artificial feedforward, utilizando algoritmo genético de retropropagação (backpropagation). A rede neural artificial (RNA) é composta de quatro camadas, entre entradas, pesos, bias, função de ativação sigmóide e saída desejada. O modelo conta com funções sigmoides, a fim de calcular e otimizar o erro através das camadas anteriores, até a entrada. Este modelo, por ser mais preciso, conta com certo momento e taxa de aprendizagem. A proposta da rede neural artificial (RNA) em feedforward, com o algoritmo genético de retropropagação (backpropagation), foi implementada em forma estrutural, e com uma interface gráfica, na qual o usuário final possa escolher a resistência desejada, tipo de cimento, tipo e dimensão de agregados graúdos, dimensão de agregados miúdos, tipo de concreto e aditivo, se for o caso de concretos de alta resistência (CAR). Nesta pesquisa, a coleta de dados, para armazenar no programa, foi realizada por meio de ensaios de caracterização dos materiais e de dosagem e resistência do concreto. A linguagem de programação Java foi utilizada para programar o algoritmo genético e a interface usuário. Foram realizados os testes e manutenção da ferramenta computacional, seguindo regras importantes no desenvolvimento de softwares. O resultado final, deste desenvolvimento, foi um software capaz de calcular a dosagem do concreto para o usuário, quando este insere valores de resistência à compressão axial desejada e o material que será usado na confecção do concreto. / The concrete production is increasingly demanding. preventive and corrective measures are used in concrete dosage, generating profits and savings in preparation. In order to achieve economy and practicality in the dosage of concrete in this study was developed after the collection of experimental data, the creation of artificial neural network feedforward using genetic algorithm backpropagation. The artificial neural network (ANN) is composed of four layers, between inputs, weights, biases, sigmoid activation functions and output desired. The model has sigmoid functions in order to calculate and optimize the error by the preceding layers, until the entrance. This model, to be more precise, has the right time and learning rate. The proposed artificial neural network (ANN) in feedforward, with the genetic algorithm backpropagation, was implemented in structural form, and with a graphical interface, in which the end user can choose the desired strength, cement type, and size of coarse aggregates, fine aggregates dimension, type of concrete and additives, if any of high strength concrete (CAR). In this research, data collection, to store the program, was carried out by means of characterization tests of materials and dosage and strength of concrete. The Java programming language was used to program the genetic algorithm and the user interface. testing and maintaining software tool were conducted following important rules in the software development. The end result of this development was an able to calculate the dosage of specific software for the user, when it enters resistance values to the desired axial compression and the material that will be used in the manufacture of concrete.
127

Determination of effective dose and entrance skin dose from dose area product values for barium studies in adult patients at a large tertiary hospital in the Western Cape

Peters, Nazlea Behardien January 2017 (has links)
Thesis (MSc (Radiography))--Cape Peninsula University of Technology, 2018. / Background and objectives The issue of patient doses received during fluoroscopy procedures, raised concerns for the researcher, as there may have been probable past skin injuries or deterministic injuries that may not have been documented. Amongst the radiology staff, there was very little understanding of what the actual dose area product (DAP) value means in real terms of effective dose and entrance skin dose. The aims of the study were to: i) Measure the radiation doses received by the patient and determine a simple means of defining the DAP value to the radiographer in terms of the dose received by the patient. ii) Determine the effective dose, entrance skin dose and the relationship with the DAP value to assist with developing a conversion co-efficient for dose indicators. Method Direct radiation dose measurements can be obtained through DAP meters attached to the diagnostic equipment, but the DAP value is not an direct indication of the effective dose received by the patient. The DAP values captured from the DICOM header information for barium fluoroscopic procedures at a large tertiary was analysed and Diagnostic Reference levels (DRL) were determined for barium swallow, meal and enema procedures. The effective and skin doses were calculated by means of the Monte Carlo program. The results were compared to published values. The relationship between the entrance skin dose and the DAP value was determined and conversion factors were calculated. Results Correlation between the DAP and entrance skin dose and comparative 75th percentile threshold values were determined for barium swallow (BaS), barium meal (BaM) and barium enema (BaE) procedures. Effective to DAP conversation factors for BaS, BaM and BaE are 0.19, 0.26 and 0.60 respectively and 0.15, 0.11 and 0.14 for entrance skin to DAP. Conclusion The the research showed the relationship between the effective dose, entrance skin dose and DAP value and a simple, practical and applicable explanation of the DAP value by means of conversion factors.
128

Idealizações de um programa baseado em redes neurais para dosagem de concreto /

Bolognini, Enio José January 2016 (has links)
Orientador: Maria da Consolação Fonseca de Albuquerque / Resumo: A produção de concreto está cada vez mais exigente. Medidas de prevenção e correção são empregadas na dosagem do concreto, gerando lucros e economia no preparo. A fim de obter economia e praticidade na dosagem de concretos, neste estudo foi desenvolvido, após a coleta de dados experimentais, a criação de rede neural artificial feedforward, utilizando algoritmo genético de retropropagação (backpropagation). A rede neural artificial (RNA) é composta de quatro camadas, entre entradas, pesos, bias, função de ativação sigmóide e saída desejada. O modelo conta com funções sigmoides, a fim de calcular e otimizar o erro através das camadas anteriores, até a entrada. Este modelo, por ser mais preciso, conta com certo momento e taxa de aprendizagem. A proposta da rede neural artificial (RNA) em feedforward, com o algoritmo genético de retropropagação (backpropagation), foi implementada em forma estrutural, e com uma interface gráfica, na qual o usuário final possa escolher a resistência desejada, tipo de cimento, tipo e dimensão de agregados graúdos, dimensão de agregados miúdos, tipo de concreto e aditivo, se for o caso de concretos de alta resistência (CAR). Nesta pesquisa, a coleta de dados, para armazenar no programa, foi realizada por meio de ensaios de caracterização dos materiais e de dosagem e resistência do concreto. A linguagem de programação Java foi utilizada para programar o algoritmo genético e a interface usuário. Foram realizados os testes e manutenção da ferramenta com... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
129

Avaliação da dose de radiação absorvida em exames radiológicos durante o planejamento radioterápico /

Camargo, Rafaela Ferraz de. January 2014 (has links)
Orientador: Batista de Oliveira Júnior / Coorientador: Marco Antonio Rodrigues Fernandes / Banca: Vladimir Eliodoro da Costa / Banca: Vidal Haddad Júnior / Resumo: A radioterapia é uma modalidade médica que emprega radiações ionizantes para o tratamento de doenças. O sucesso da terapêutica depende de vários fatores, dentre eles a liberação precisa da dose de radiação no volume tumoral e a perfeita reprodutibilidade diária das orientações prescritas na ficha técnica do paciente. A delimitação do campo de radiação, o qual deve abranger todo o tumor e permitir uma margem de segurança que considere a movimentação anatômica, é feita durante os procedimentos de planejamento radioterápico. Nesta etapa do tratamento, o médico radioterapeuta, auxiliado pelo físico médico e o tecnólogo em radiologia, utiliza técnicas radiográficas através de um sistema de escopia para visualização do volume alvo de irradiação, e realiza imagens radiográficas estáticas para documentação do caso clínico. Na rotina dos procedimentos de planejamento radioterápico, normalmente não é feita a quantificação da dose de radiação liberada no procedimento, devido principalmente à grande e exaustiva agenda de atividades dos profissionais envolvidos. Neste trabalho foi avaliada a dose de radiação liberada em exames radiológicos realizados durante o planejamento radioterápico, avaliando a influência desta dose no total de exposições em que o paciente foi submetido durante todo o curso da radioterapia. A pesquisa consistiu no acompanhamento dos procedimentos de planejamento radioterápico executadas no Serviço Técnico de Radioterapia da Faculdade de Medicina da UNESP de Botucatu, extraindo os valores das técnicas radiográficas empregas para diferentes planejamentos. Após a caracterização individualizada do planejamento, as técnicas radiográficas utilizadas em cada um dos casos clínicos, foram repetidas e as doses de radiação liberadas no procedimento foram quantificadas por meio de detectores de radiação específicos e calibrados para a energia dos raios-x de ... / Abstract: Radiotherapy is a medical modality that uses ionizing radiation for the treatment of diseases. The treatment success depends on several factors, including the precise release of the radiation dose in the tumor volume and the perfect daily reproducibility of the guidelines prescribed in the technical sheet of the patient. The delimitation of the radiation field, which should cover the entire tumor and allow a safety margin that considers the anatomical movement, is taken during the procedures of the radiotherapy planning. At this stage of treatment, the radiotherapist physician, aided by the medical physicist and the technologist in radiology, utilizes radiographic techniques through a system of scopy to visualize the target volume of irradiation, and performs static radiographic images to document the clinical case. In the routine of the radiotherapy planning procedures, usually is not performed the quantification of the radiation dose released in the procedure, mainly due to the large and exhaustive schedule of activities of the professionals involved. In this study, was assessed the radiation dose released in radiological examinations performed during the radiotherapy planning, evaluating the influence of this dose in the exposures total in which the patient has undergone throughout the radiotherapeutic procedure. The research consisted in monitoring the radiotherapy planning procedures performed at UNESP, "Serviço Técnico de Radioterapia" of "Faculdade de Medicina de Botucatu", extracting the radiographic technique values used for different plannings. After the individualized characterization of the plannning, the radiographic techniques used in each clinical case, were repeated and the radiation doses released in the procedure were quantified by specific radiation detectors and they were calibrated to the energy of the simulation x-ray. It is concluded that the absorbed radiation dose, which ... / Mestre
130

Dosagem de etanol utilizando alcool desidrogenase de levedura de panificação /

Reis, Juliana Pereira Zanon. January 2006 (has links)
Resumo: O presente trabalho descreve e compara duas metodologias enzimáticas de dosagem de etanol (métodos UV e colorimétrico), que utilizam desidrogenase alcoólica (álcool: NAD+: oxidoredutase EC 1.1.1.1) de fermento de panificação (Mauri Brasil Ind. Comp. e Imp. Ltda), adquirida no comércio na forma desidratada. A atividade da álcool desidrogenase (ADH) presente no extrato bruto de levedura de panificação, da ordem de 5,66 U/mL, foi utilizada nos ensaios colorimétricos, enquanto que nos ensaios no ultravioleta (UV), atividades ao redor de 30 U/mL foram obtidas através da otimização das condições de extração e purificação parcial da ADH. A estabilidade da ADH foi mantida durante 2 meses, na forma liofilizada a 4oC (retenção de 96,2% de sua atividade), na presença de 1 mM de azida de sódio. A mesma preparação enzimática, reconstituída em PEG 15% e armazenada durante 12 meses em freezer (-18oC), apresentou retenção de 50% de sua atividade até 2 meses. O método ultravioleta de dosagem de etanol (detecção na faixa de 2,3 x 10-4 g/L a 6,91 x 10-3 g/L ou 5 æM a 150 æM) baseia-se na conversão enzimática do etanol a acetaldeído, através de reação de óxido-redução, tendo o NAD+ como aceptor de elétrons. O NADH formado pela reação é quantificado com leituras espectrofométricas a 340 nm, conforme descrito por Gattás (2002). Uma preparação enzimática parcialmente purificada e diluída foi utilizada na quantificação de etanol em diferentes bebidas, mostrando desvios dos teores alcoólicos de no máximo 2,1% quando comparados às especificações do produtor. O ensaio de etanol em vinho foi realizado com recuperação da ordem de 99,25% em amostra contendo, originalmente, 249,65 g/L de etanol. O método colorimétrico de dosagem de etanol (detecção na faixa de 4,6 x 10-2 g/L a 23,0 x 10-2 g/L ou 1000 æM a 5000 æM)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work describes and compares two enzymatic methodology of ethanol dosage (UV and colorimetric methods), that use alcohol dehydrogenase (alcohol: NAD+: oxidoredutase EC 1.1.1.1) of baker’s yeast (Mauri Brasil Ind. Comp. e Imp. Ltda) acquired in the commerce in the dry form. The activity of the alcohol dehydrogenase (ADH) at around 5.66 U/mL present in the crude extract of baker’s yeast was used in the colorimetric assay, whereas activities at around of 30 U/mL were obtained through the optimization of the extraction conditions and partial purification of ADH in the ultraviolet assay (UV). The stability of liophilized ADH at 4ºC was maintained for 2 months (retention of 96.2% of activity) in the presence of 1 mM sodium azide. The same enzymatic preparation reconstituted in PEG 15% and stored for 12 months in freezer (-18ºC) presented retention of 50% of your activity up to 2 months. The ultraviolet method of ethanol dosage (detection range of 2.3 x10-4 g/L to 6.91 x 10-3 g/L or 5 æM to 150 æM) is based on the enzymatic conversion of ethanol into acetaldehyde, through oxido-reduction reaction with NAD+ as the aceptor of electrons. The NADH formed by the reaction was quantified spectrophotometrically at 340 nm, as described by Gattás (2002). A partially purified and diluted enzymatic preparation was used for ethanol quantification in different beverages, showing alcoholic contents deviations up to 2.1% when compared to the specifications of the manufacturer. The ethanol assay in wine was accomplished with a recovery at around 99.25% in sample originally containing 249.65 g/L of ethanol. The colorimetric method of ethanol dosage (detection range of 4.6 x 10-2 g/L to 23.0 x 10-2 g/L or 1000 æM to 5000 æM) uses the color reagents system MTT/PMS dissolved in saline phosphate buffer (PBS), determined spectrophotometrically at 570-655 nm... (Complete abstract, click electronic address below) / Orientador: Edwil Aparecida de Lucca Gattás / Coorientador: Maristela de Freitas Sanches Peres / Banca: Rubens Monti / Banca: Luis Henrique Souza Guimarães / Mestre

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