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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.
31

Cargas de trabalho e desgastes de profissionais das técnicas radiológicas em serviço de radiologia convencional

Anderson, Tiago Jorge January 2016 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde, Programa de Pós-Graduação em Enfermagem, Florianópolis, 2016 / Made available in DSpace on 2017-05-23T04:24:12Z (GMT). No. of bitstreams: 1 345298.pdf: 1178661 bytes, checksum: c52d857365b1f5f6cbbbf716b9b070f5 (MD5) Previous issue date: 2016 / Trata-se de uma pesquisa qualitativa, descritiva e exploratória realizada em hospital estadual geral situado no sul do Brasil. Teve como objetivo descrever as cargas de trabalho e os desgastes presentes no processo de trabalho dos profissionais das técnicas radiológicas de um serviço de radiologia convencional. Para o embasamento teórico do estudo utilizou-se o referencial teórico da Medicina Social Latinoamericana de Laurell e Noriega que aborda o conceito de cargas de trabalho e processo de desgaste. A coleta de dados, utilizou a entrevista semi-estruturada com 12 trabalhadores, a observação participante de 50h horas de trabalho e a validação consensual com três grupos, esta última, adaptada do Modelo Operário Italiano. Para subsidiar a análise dos dados usou-se a Análise Temática pautada em Braun e Clarke. Emergiram dois grandes temas: um relacionado às cargas de trabalho e outra relacionado ao desgaste profissional dos profissionais das técnicas radiológicas. Na temática relacionada as cargas de trabalho evidenciou-se que estes profissionais encontram-se expostos a cargas biológicas, fisiológicas, psíquicas e mecânicas. Na temática relacionada aos desgastes profissionais, destacou-se que os trabalhadores das técnicas radiológicas apresentam desgastes osteoarticulares, psíquicos e relacionados ao sistema respiratório. A pesquisa aponta que os profissionais das técnicas radiológicas se encontram expostos a fluidos corporais, superfícies e equipamentos contaminados com microorganismos, manipulação excessiva de peso, trabalho noturno, radiação ionizante, extremos de temperatura, sobrecarga de trabalho, problemas éticos, vulnerabilidade a violência e queda por piso molhado. Destaca que essas cargas ao interagirem com o corpo do trabalhador em radiologia convencional geram diferentes tipos de desgastes destacando-se as dores em ombros e coluna vertebral, estresse e desgaste emocional, além de resfriados, pneumonia e rinite. Ao se contextualizar as temáticas geradas pela análise dos dados observou-se que as cargas de trabalho e os desgastes apresentados pelos profissionais das técnicas radiológicas são comuns a outros trabalhadores da saúde. A presente pesquisa permitiu dar visibilidade as cargas de trabalho e desgastes enfrentados pelos profissionais das técnicas radiológicas em serviço de radiologia convencional, categoria essa abordada de forma tímida nas pesquisas que envolvem saúde do trabalhador. Destacou-se também a relevância da utilização do Modelo Operário Italiano como referencial teórico em pesquisas envolvendo a saúde do trabalhador, uma vez que ela valoriza o saber dos trabalhadores e permite que os trabalhadores não atuem apenas como fontes de informação, mas também como sujeitos da informação.<br> / Abstract : This text is a qualitative, descriptive and exploratory research conducted in a State Hospital in southern part of Brazil. This research intends to describe the workload and wear presented in working process of Medical Radiation Technologists in a conventional radiology service. We used the theoretical framework by Latin-American Social Medicine such as Laurell and Noriega whom discusses the concept of workload and wear. The data collection was based on a half-structured interview with 12 workers, on an observation and participation of 50 hours of work and on consensual validation with three groups, this one adapted from the Italian Worker Model. Thus, we made the analysis of data based on the Thematic Analysis conceived by Braum and Clarke. Therefore, two great subjects have emerged: the first one related to workload and the other one related to the professional wear of Medical Radiation Technologists. In the subject related to workload, it was apparent that these professionals were exposed to biological, physiological, psychological and mechanical loads. In the subject related to professional wearing we highlighted that radiology professionals presented osteoarticular, psychological wearing and problems in respiratory system. This research indicates that Medical Radiation Technologists are exposed to: body fluids, surfaces and equipment contaminated by micro-organism, excessive load manipulation, night work, ionizing radiation, extreme temperature, overload of work, ethical problems, vulnerability and fall because due to wet floor. We emphasize that these loads interact with the worker's body in conventional radiology and they promote different types of wearing such as: shoulder pain and spine pain, stress and emotional wearing besides colds, pneumonia and rhinitis. Contextualizing these subjects created by the data analysis, we noticed that workload and wearing presented by these Medical Radiation Technologists are common to others Healthcare workers. The research allowed us to give visibility to workload and wearing confronted by Medical Radiation Technologists in Conventional Radiology Service. This category is still early studied in Healthcare and Work researches. We emphasized the important utilization of Italian Worker Model as a theoretical framework involving Worker's Health. It values the worker's knowledge and allows them to be not just source of information but also subjects of information.
32

Otimização de imagem de torax para radiografia computadorizada

Velo, Alexandre França [UNESP] 30 October 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-10-30Bitstream added on 2014-06-13T19:28:41Z : No. of bitstreams: 1 velo_af_me_botib.pdf: 2027153 bytes, checksum: 75d4e59757a87a168a8558deb0356dce (MD5) / Os métodos que utilizam radiações ionizantes ainda são os mais empregados por serem considerados mais “baratos” e sobretudo, muito eficientes quando utilizados com controle e qualidade. Novos sistemas de aquisição, registro e armazenamento de imagens estão sendo desenvolvidos, dentre os quais podemos citar a radiologia computacional e digital. Este método de diagnóstico pode proporcionar maior qualidade da imagem, favorecendo a não repetição de exames de modo a contribuir com a redução de dose para o paciente, quando utilizado com controle e qualidade. A otimização da relação risco-benefício é considerada de grande avanço no que diz respeito à radiologia convencional, entretanto essa não é a realidade da radiologia computacional e digital, onde não dispomos de normas e protocolos estabelecidos para otimização da imagem, dose e custo para a rotina clinica de radiodiagnóstico. Esta pesquisa teve como objetivo a otimização de imagens radiográficas computacionais de tórax (na projeção Póstero Anterior - PA). A escolha por essa modalidade de exame se deve ao fato deste ser o exame convencional mais realizado na rotina clínica. Para atingir esse objetivo foram utilizados fantomas homogêneos que simulam características de absorção e espalhamento da radiação próxima à do tórax de um paciente padrão, com aproximadamente 1,73m e 75 kg. Neste estudo o Fantoma homogêneo Equivalente ao Paciente (FEP) foi utilizado na calibração do sistema de imagem computacional, de modo a obter índices de exposições (lgMs) previamente definidos para cada tensão (kVp). As técnicas calibradas foram aplicadas em um fantoma antropomórfico (RANDO). As imagens obtidas foram avaliadas, por um especialista da área de radiologia, o qual identificou a melhor imagem (imagem ótima), para cada kVp, para determinadas possíveis anomalias no pulmão... / The ionizing radiation methods are still the most commonly used for being considered cheaper and very efficient when used with control and quality. New acquisition, recording and image storage systems are being developed among which we can mention the Computed Radiography and Digital Radiography. This method of diagnosis might provide higher image quality, favoring unrepeated examinations in order to contribute to the patient dose reduction when used with control and quality. The risk-benefit rate optimization is considered a breakthrough in computed radiology, however it’s not the reality of the computed and digital image, which do not have well established norms and protocols for image, dose and expense optimization in the radiodiagnostic clinical routine. This research had as objective the optimization of computed radiographic images of the chest (anterior - posterior projection). The choice of this modality exam was due the fact that it is the most realized on clinical routine. To achieve this objective it was used an homogeneous phantom that simulates spreads and absorption characteristics of radiation next to a standard patient, with 1, 73 m and 75 Kg approximately. On this study, the Phantom Equivalent of Patient (PEP) was used to calibrate the computational image system, acquiring exposure index (lgMs) previously defined to each kVp. The calibrated techniques were applied on an Anthropomorphic Phantom (RANDO). The images were evaluated by a radiology specialist whose identified the best image (optima image) for each kVp to determine possible anomalies on lung / bones lesions using the Visual Gradual Assessment (VGA). After the optima images selection, the radiologist used the VGA relative to select the image standard, where it stood out by its “image beauty”. Based on 3D principle (Dose, Diagnostic, Dollar), respecting this order... (Complete abstract click electronic access below)
33

Otimização de imagem de torax para radiografia computadorizada /

Velo, Alexandre França. January 2012 (has links)
Orientador: Jose Ricardo de Arruda Miranda / Coorientador: Diana Rodrigues de Pina / Banca: Sério Marrone Ribeiro / Banca: Homero Schiabel / Resumo: Os métodos que utilizam radiações ionizantes ainda são os mais empregados por serem considerados mais "baratos" e sobretudo, muito eficientes quando utilizados com controle e qualidade. Novos sistemas de aquisição, registro e armazenamento de imagens estão sendo desenvolvidos, dentre os quais podemos citar a radiologia computacional e digital. Este método de diagnóstico pode proporcionar maior qualidade da imagem, favorecendo a não repetição de exames de modo a contribuir com a redução de dose para o paciente, quando utilizado com controle e qualidade. A otimização da relação risco-benefício é considerada de grande avanço no que diz respeito à radiologia convencional, entretanto essa não é a realidade da radiologia computacional e digital, onde não dispomos de normas e protocolos estabelecidos para otimização da imagem, dose e custo para a rotina clinica de radiodiagnóstico. Esta pesquisa teve como objetivo a otimização de imagens radiográficas computacionais de tórax (na projeção Póstero Anterior - PA). A escolha por essa modalidade de exame se deve ao fato deste ser o exame convencional mais realizado na rotina clínica. Para atingir esse objetivo foram utilizados fantomas homogêneos que simulam características de absorção e espalhamento da radiação próxima à do tórax de um paciente padrão, com aproximadamente 1,73m e 75 kg. Neste estudo o Fantoma homogêneo Equivalente ao Paciente (FEP) foi utilizado na calibração do sistema de imagem computacional, de modo a obter índices de exposições (lgMs) previamente definidos para cada tensão (kVp). As técnicas calibradas foram aplicadas em um fantoma antropomórfico (RANDO). As imagens obtidas foram avaliadas, por um especialista da área de radiologia, o qual identificou a melhor imagem (imagem ótima), para cada kVp, para determinadas possíveis anomalias no pulmão... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The ionizing radiation methods are still the most commonly used for being considered cheaper and very efficient when used with control and quality. New acquisition, recording and image storage systems are being developed among which we can mention the Computed Radiography and Digital Radiography. This method of diagnosis might provide higher image quality, favoring unrepeated examinations in order to contribute to the patient dose reduction when used with control and quality. The risk-benefit rate optimization is considered a breakthrough in computed radiology, however it's not the reality of the computed and digital image, which do not have well established norms and protocols for image, dose and expense optimization in the radiodiagnostic clinical routine. This research had as objective the optimization of computed radiographic images of the chest (anterior - posterior projection). The choice of this modality exam was due the fact that it is the most realized on clinical routine. To achieve this objective it was used an homogeneous phantom that simulates spreads and absorption characteristics of radiation next to a standard patient, with 1, 73 m and 75 Kg approximately. On this study, the Phantom Equivalent of Patient (PEP) was used to calibrate the computational image system, acquiring exposure index (lgMs) previously defined to each kVp. The calibrated techniques were applied on an Anthropomorphic Phantom (RANDO). The images were evaluated by a radiology specialist whose identified the best image (optima image) for each kVp to determine possible anomalies on lung / bones lesions using the Visual Gradual Assessment (VGA). After the optima images selection, the radiologist used the VGA relative to select the image standard, where it stood out by its "image beauty". Based on 3D principle (Dose, Diagnostic, Dollar), respecting this order... (Complete abstract click electronic access below) / Mestre
34

Development of advanced strategies for the prediction of toxicity endpoints in drug development

Carrió Gaspar, Pau, 1982- 11 December 2015 (has links)
Safety concerns are one of the main causes of drug attrition. In these events, the moment at which the drug toxic effects are discovered changes dramatically the importance of the finding; discarding a valuable candidate at clinical testing stages means wasting years of efforts and huge economicinvestments. Even more dramatic is the discovery of toxic effect at post marketing stages, when the drug could have already produced severe side effects on a number of patients. For these reason there is a pushing need of developing methods able to assess the safety of drug candidates at early stages of development. Among these, in silico methods have many advantages, like not even requiring the availability of the compound, not wasting any quantity of it in case it has been already synthesized, being fast, cheap and make no use of animal testing. Unfortunately, in silico prediction methods of toxicity endpoints do not perform always as expected. The reasons are still under debate, but likely reasons are the complexity of the biological phenomena under study and the large structural diversity of the drug candidates, among others. The aim of this thesis is to improve currently used in silico prediction methods for their application to biological endpoints of interest in drug development, with a special emphasis to toxicological endpoints. Here, we report a novel general methodology called ADAN (Applicability Domain Analysis) for assessing the reliability of drug property predictions obtained by in silico methods. Furthermore, we proposed a unifying strategy for the use of in silico predictive methods in this field, defining rational criteria for the application of a whole spectrum of methods; from structural alerts to global QSAR models, including read across and local models. The usefulness of all the proposed methodologies is tested using a systematic analysis on representative datasets, obtaining good results that confirm their validity. / La manca de seguretat és una de les raons principals per la qual els candidats a fàrmacs són descartats. La fase en què els possibles efectes tòxics són identificats és crítica: descartar un candidat en fase clínica implica la pèrdua d'anys d'esforços i enormes inversions econòmiques. Encara pitjor és identificar efectes tòxics un cop el fàrmac està comercialitzat, quan es poden haver produït greus efectes secundaris en pacients. Per aquestes raons hi ha la necessitat de desenvolupar mètodes capaços d'avaluar la seguretat dels candidats a fàrmacs en les primeres etapes. Entre aquests, els mètodes in silico tenen molts avantatges, com no requerir la disponibilitat del compost, no perdre cap quantitat en cas que ja s'hagi sintetitzat, ser ràpid, econòmic i no fer ús de l'experimentació amb animals. Per desgràcia, els mètodes de predicció in silico aplicats a criteris d'avaluació de toxicitat no produeixen els resultats adequats. Les raons són objecte de debat, però raons probables són la complexitat dels fenòmens biològics en estudi i la gran diversitat estructural els fàrmacs candidats, entre d'altres. L'objectiu d'aquesta tesi és millorar els mètodes de predicció in silico emprats en l’avaluació de criteris d'interès en el desenvolupament de fàrmacs amb especial èmfasi en els de toxicitat. Presentem una nova metodologia general anomenada ADAN (Applicability Domain Analysis) per avaluar la fiabilitat de les prediccions obtingudes amb mètodes in silico. A més, proposem una estratègia unificada de l’ús de mètodes de predicció in silico emprats en aquest camp; com alertes estructurals, read-across, QSAR local i global. La estratègia incorpora criteris racionals per la seva utilització. Els bons resultats obtinguts amb dades representatives confirmen la validesa de les metodologies.
35

Comparative study of dedicated Monte Carlo simulation codes for the performance evaluation of the small animal PET systems

Popota, Foteini D.,1980- 27 November 2014 (has links)
Positron emission tomography (PET) has been well established the last years as a powerfull tool in research and clinical applications. Advances in technology have enabled the use of small animal PET imaging in preclinical applications although the size differences in humans and rodents create many challenges to this imaging modality. In this thesis, the performance evaluation ofsmall animal PET systems through specific standards and Monte Carlo simulation codes are investigated using the microPET R4 system. In the first part, the performance evaluation of the microPET R4 scanner according to the new NEMA NU 4-2008 standards for small animal positron emission tomography is assessed and a comparison against its previous evaluation according to the adapted clinical NEMA NU 2-2001 standards is presented. In the second part, dedicated Monte Caro simulation models (using GATE and PeneloPET) of the performance of the R4 system is compared against experimental data. / La tomografia per emissió de positrons (PET) és una poderosa eina per a la investigació translacional adreçada constantment al repte de les noves tecnologies. Per tant, els aspectes tècnics són cada vegada més rellevants en el disseny i desenvolupament de nous sistemes de PET. El coneixement de les característiques físiques és el punt clau especialment en el cas de les tècniques d'imatge de petits animals. Per a la optimització de les capacitats dels sistemes de PET per animals de laboratori, el seu rendiment ha de ser avaluat mitjançant protocols específics i codis de simulació de MonteCarlo. En aquesta tesi, en la primera part, es presenta l'avaluació del rendiment de l'escàner microPET R4 d'acord amb les normes NEMA NU 4-2008 de la tomografia per emissió de positrons petit animal és compara amb l'avaluació anterior realitzada d'acord amb la clínica adaptada NEMA NU 2-2001. Es van obtenir diferències en els resultats entre NEMA NU 4-2008 i NEMA NU 2-2001 associat a la utilització de diferents fantoms i finestres d'energia. A la segona part, es compara l’ exactitud de diferents codis de simulació Monte Carlo (utilitzant GATE i PeneloPET) per avaluar el rendiment del sistema de R4 en relació a les dades experimentals. Tots dos codis van proporcionar resultats exactes si bé PeneloPET va demostrar ser més ràpid que GATE
36

Study of thyroid hormone disruption by the environmental contaminant bde-99 in perinatal rats

Blanco Pérez, Jordi 25 October 2013 (has links)
Los contaminantes ambientales difenil éteres polibromados (PBDEs) se encuentran en altas concentraciones en mujeres. El propósito de la presente tesis es el estudio de la toxicidad ocasionada por el traspaso materno de BDE-99 sobre la descendencia. Entre los resultados más destacables, se encontró que la exposición materna al BDE-99 induce toxicidad en fetos de rata causando retraso en la formación de los huesos, ligera hipertrofia de corazón e hígado y fomentando el aumento de producción de substancias reactivas de oxigeno (ROS) en el hígado de los fetos debido a una mayor actividad de las enzimas p450 (CYP). Por otra parte, las crías de rata mostraron un retraso en la tarea de aprendizaje espacial y un efecto ansiolítico de forma dosis-dependiente después de la lactancia. También se encontró que los niveles en suero de hormonas tiroideas disminuyeron y mostraron signos de hapatoxicidad. Estos resultados indican que realmente existe un efecto toxico del contaminante BDE-99 sobre la descendencia de rata a concentraciones encontradas en humanos. / The main human concern about the environmental pollutants polybrominated diphenyl ethers (PBDEs) are the rising concentrations accumulated in women. The aim of the present thesis is the study of the toxicity by maternal transference of BDE-99 in the offspring. Among highlights of the results, we found that exposure to BDE-99 during the gestational period produced a delayed ossification, slight hypertrophy of the heart, and enlargement of the liver in rat fetuses. A transplacental effect of BDE-99, evidenced by the activation of nuclear hormones receptors that induce the upregulation of P450 isoforms, was also found in fetal liver correlated with an increase of reactive oxygen substances. Maternal transference of BDE-99 also produced a delay in the spatial learning task and a significant dose-response anxiolytic effect when rat pups were weaned. It was also found that the serum levels of thyroid hormones decreased and signs of hepatoxicity were observed. These results indicate a clear signal of toxicity in rat offspring by BDE-99 at levels comparable to those found in humans.
37

MDMA pharmacology in humans and serotonergic effects

Yubero Lahoz, Samanta, 1985- 18 November 2013 (has links)
3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is one of the most abused recreational drugs in the world. It has been extensively reported that this drug inhibits its own metabolism by inhibiting a polymorphic liver enzyme, CYP2D6, which is responsible for the clearance of one quarter of drugs used in therapeutics. This phenomenon has important clinical implications, since MDMA users display a higher prevalence of psychopathology, particularly of mood disorders, compared to control population. Importantly, these psychiatric diseases are treated with drugs most of them substrate of this enzyme. In addition, it is not elucidated how MDMA is still metabolically cleared even after repeated drug doses. Therefore, the first part of this thesis was focused on studying the metabolic autoinhibition by MDMA assessing several liver enzyme activities in men and women. Although MDMA pharmacology is well established, is it still not clear which is the mechanism of action of the drug. MDMA interacts with the serotonergic system at several levels, but nowadays is technically difficult to study the serotonergic function in living human brain. Imaging methods are limited by a number of factors. Thus, it would be advantageous to have a reliable peripheral index of the serotonergic activity in the blood. The second part of this thesis presents the development of several approaches aimed to assess whether the serotonin transporter in platelets can be used as a peripheral biomarker for central serotonergic activity, and determine if it plays any role in drug mechanism of action. / La 3,4-metilendioximetanfetamina (MDMA, èxtasi) és una de les drogues més consumides al món. Aquesta droga inhibeix el seu propi metabolisme, inhibint un enzim polimòrfic del fetge, el CYP2D6, que és el responsable de l’eliminació d’una quarta part dels medicaments. Aquest fet té implicacions clíniques rellevants, ja que els consumidors de MDMA presenten una prevalença de psicopatologia més alta respecte a la població no consumidora, i moltes de la patologies psiquiàtriques es tracten amb fàrmacs substrats d’aquest enzim. A més, encara no s’ha discernit com aquesta droga pot ser eliminada de l’organisme, inclús després d’haver-ne consumit dosis de manera repetida. Així doncs, la primera part d’aquesta tesi es centra en estudiar l’autoinhibició de la MDMA determinant l’activitat de diferents enzims del fetge, en homes i dones. Encara que la farmacologia de la MDMA està descrita a fons, no està del tot clar quin és el seu mecanisme d’acció. La MDMA interactua amb el sistema serotonèrgic de diverses maneres, però avui en dia és molt difícil estudiar tècnicament el sistema serotonèrgic en el cervell humà. Les tècniques d’imatge estan limitades per molts factors, i per tant, seria molt útil tenir un índex perifèric a la sang de l’activitat serotonèrgica al sistema nerviós central. La segona part d’aquest tesi s’enfoca en el desenvolupament de tècniques per determinar a diferents nivells si el transportador de la serotonina a les plaquetes podria ser un bon biomarcador perifèric de la seva activitat al cervell, i d’aquesta manera veure si el sistema serotonèrgic està implicat en el mecanisme d’acció de la MDMA.
38

Avaliação radiográfica da reabsorção óssea periodontal por meio de valor de pixel e comparação com análise histopatológica / RADIOGRAPHIC EVALUATION OF PERIODONTAL BONE RESORPTION WITH PIXEL VALUE AND HISTOPATOLOGICAL ANALYSIS.

Schmitd, Ligia Buloto 25 April 2005 (has links)
Avaliar radiograficamente a reabsorção óssea periodontal por meio do valor de pixel e sua comparação com o exame histopatológico foi o objetivo deste trabalho. Trinta ratos Wistar foram submetidos à indução de doença periodontal com fio de seda 3-0 ao redor do primeiro molar inferior direito e o lado esquerdo foi deixado como controle. O grupo 1 foi sacrificado após passados 7 dias, o grupo 2, após 14 dias e o grupo 3 após 28 dias. As hemimandíbulas dos 30 animais foram radiografadas em filmes radiográficos tamanho 2 e na placa fotoestimulável de fósforo do sistema Digora®. As radiografias convencionais foram digitalizadas em um scanner a laser. As peças foram processadas para cortes microscópicos e coradas em HE para análise. As médias dos valores dos pixels das áreas de doença e das áreas controle foram aferidos no programa ImageJ®. O teste ANOVA a dois critérios mostrou que os valores dos pixels das áreas de doença periodontal foram significantemente menores do ponto de vista estatístico, quando comparados às áreas de controle, tanto para as radiografias obtidas com o sistema Digora®, quanto para as digitalizadas. No entanto, a ANOVA a um critério das médias dos valores dos pixels das áreas de doença periodontal não mostrou diferença estatisticamente significante entre os diferentes períodos experimentais. A análise microscópica evidenciou perda óssea, com aumento de osteoclastos e diminuição da altura da crista óssea alveolar com o passar do período experimental. Como conclusão, a análise do valor de pixel de uma radiografia digital foi capaz de evidenciar perda óssea quando comparada com seus controles, mas falhou ao detectar as alterações ósseas progressivas que foram visualizadas microscopicamente. / The aim of this research was to evaluate the pixel value modification in periodontal disease sites using direct digital radiography and digitalized radiography. Periodontal disease was induced by a 3-0 silk ligature in the inferior right first molars of thirty Wistar rats. The inferior left first molar was the control. The animals were divided into groups: 1- seven days; 2- fourteen days and 3- twenty eight days. The mandibles were removed and radiographed with film size 2 and in a photoestimulable phosphor plate (Digora®). Conventional radiographs were digitized in a laser scanner. The mandibles were processed and HE stained for histological analysis. The mean pixel values from the periodontal disease sites were measured by histogram analysis by the software ImageJ®. There was an ANOVA test statistic significant difference among the pixel values for disease sites when compared to the control sites in the three groups for Digora® and digitized images. However, there was no significant difference for the disease sites regardind the pixel values among experimental periods. The longer the experimental period, more severe was the bone loss visualized histologically. In conclusion, pixel value analysis in a digital radiographic image may evidence bone loss when compared to the controls, but failed in detecting the progressive bone loss microscopically visualized.
39

La Hormona de crecimiento en el ámbito deportivo : métodos de detección, comparación y funcionamiento metodológico

Bosch Colom, Jaume, 1954- 03 December 2012 (has links)
This doctoral thesis describes the evaluation of analytical methodologies to detect human growth hormone (hGH) abuse in sport. Two main strategies are studied and compared. The first (direct method) measures changes in the proportions of hGH variants, expressed as ratios, which are altered after hGH administration. Two versions of the direct method are compared; one using ratios between recombinant and pituitary variants and a second using ratios between only 22 and 20 kDa hGH variants. To fully understand the immunoassays readings, all relevant antibodies were characterised by surface plasmon resonance (SPR). A second strategy (indirect method) measures changes in proteins, other than hGH, provoked by the use of hGH. These bio-markers should have a longer retrospective analytical power. To evaluate the performance of both strategies, two clinical trials with recombinant hGH (rhGH) were carried out with healthy male subjects. The resulting data have been compared and statistically assessed. It is the first time that all available strategies have been applied on a single data set and this allows better understanding of the analytical readings which provides an additional tool in the evaluation of anti-doping analyses. / Esta tesis doctoral describe la evaluación de métodos analíticos para detectar el abuso de hormona de crecimiento humana (hGH) en el deporte. Se han estudiado y comparado dos estrategias. La primera o método directo mide cambios en la proporción de variantes de hGH expresados como ratios, que están alterados después de administrar hGH. Dos versiones del método directo son comparadas; una con ratios entre variantes recombinante e hipofisaria y otra con ratios entre variantes de 22 y de 20 kDa. Para una mejor comprensión, los anticuerpos relevantes utilizados en los inmunoensayos, se caracterizaron por medio de resonancia del plasmon de superficie (SPR). Una segunda estrategia o método indirecto mide cambios en bio-marcadores (proteínas) causados por uso de hGH recombinante (rhGH). Estos bio-marcadores presentan un poder analítico más fuerte y de mejor retrospección en el tiempo. Para evaluar el rendimiento de ambas estrategias se han realizado dos ensayos clínicos con rhGH en varones sanos. Los datos resultantes se han comparado y evaluado estadísticamente. Es la primera vez que ambas estrategias se han aplicado sobre una misma serie de datos y ello permite una mayor comprensión de lecturas analíticas lo que proporciona herramientas adicionales en la evaluación de los análisis anti-dopaje.
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Assessment of growth hormone secretagogues in anti-doping

Pinyot Comelles, Armand, 1981- 24 October 2012 (has links)
La present tesis doctoral desenvolupa una nova metodologia analítica antidopatge. Degut a que actualment la detecció de l'abús d'hormona del creixement recombinant està relativament resolt, es tem que els secretagogs de la hormona del creixement (GHS) siguin el relleu natural ja que es creu provoquen efectes anabòlics semblants. L'objectiu de la tesi és la detecció de secretagogs de l'hormona del creixement (GHS) a partir de mostres d’orina. Els GHS presenten gran diversitat estructural que fa difícil una única determinació química convencional. Per això s'ha optat per utilitzar la seva propietat comú d'interaccionar amb el receptor específic GHS-R1a, mitjançant un mètode basat en un assaig competitiu front un lligand marcat. Monitorant la senyal del lligand marcat al final de l’assaig es pot determinar la presència de qualsevol GHS a la mostra. S'ha determinat per l’assaig un valor de tall de la senyal del lligand marcat per sota de la qual una mostra és considerada sospitosa amb una baixa probabilitat d'obtenir un fals positiu. El mètode desenvolupat ha funcionat amb els 8 GHS estudiats, incloses mostres reals procedents d'un assaig d’administració d’un d’ells. Variables com l'edat, gènere o exercici físic no provoquen interferències en el mètode, que actualment es troba en fase de validació. / The presented doctoral thesis describes de development of a new analytical method in anti-doping. At present, the detection of recombinant growth hormone abuse is relatively settled, and therefore it is anticipated that growth hormone secretagogues (GHS) will replace GH, as they can induce similar anabolic effects. The aim of this thesis is the detection of growth hormone secretagogues (GHS) from urine samples. GHS presents high structural diversity rendering very difficult a single conventional chemical determination for all. Thus, in this approach the single feature shared by all GHS, interaction with the specific receptor GHS-R1a, is targeted using a method based on a competitive assay against a labelled ligand. By monitoring the signal of the labelled ligand at the end of the test, the presence of any GHS in the sample can be determined. A threshold value below which a sample is considered suspicious with low probability of being false positive was set up. The developed methodology was tested with 8 different GHS, and also samples from an administration assay of one of the GHS. Variables such as age, gender or physical exercise do not interfere with the method, which is currently under validation.

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