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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.
141

Daily three-dimensional ultrasound imaging for Monte Carlo based adaptive radiotherapy of prostate cancer

Chen, Yong January 2009 (has links)
No description available.
142

Image-based dose correlation studies on radiation- induced lung injury

Lee, SangKyu January 2011 (has links)
No description available.
143

ImaSim, a simulation software package for the teaching of medical x-ray imaging

Landry, Guillaume January 2009 (has links)
No description available.
144

Cone-beam computed tomography: imaging dose during CBCT scan acquisition and accuracy of CBCT based dose calculations

Giles, David January 2010 (has links)
No description available.
145

Balancing Risk and Benefit in Medical Radiology

Scally, Andy J. January 2008 (has links)
This book provides an introductory overview of a wide range of commonly encountered medical imaging tests including radiation- based techniques such as plain film radiography, computed tomography and nuclear medicine, and non-ionising imaging techniques such as medical ultrasound and magnetic resonance imaging... Chapter 7 Balancing risk and benefit in diagnostic imaging.
146

Avaliação dos recursos de mensuração em diferentes sistemas de radiografia digital / Evaluation of the mensurement resources in different systems of digital x-ray

Hernandez, Angelica Maria 09 March 2009 (has links)
Os avanços tecnológicos na área de radiologia digital proporcionam a cada dia novas informações e aplicações de seus sistemas, tornando-se assim ferramenta indispensável para a comunicação e administração de informações entre profissionais e pacientes. A proposta neste estudo foi comparar o fator de correção da ferramenta de medida de três diferentes sistemas de radiografia dentária digital, em maxila de crânios secos, na região de pré-molares, onde existe a influência natural de ângulos verticais, para avaliar o grau de confiabilidade da ferramenta de mensuração, com os padrões de calibração, quando estas medidas forem realizadas na maxila. Para este estudo foram selecionados 10 pré-molares superiores, os quais foram extraídos de seus alvéolos para obtenção do Padrão Ouro (PO) com auxílio de um paquímetro digital. Padrões metálicos foram utilizados para a realização das medidas calibradas, de 5mm e de 10mm, estes localizaram-se sob a superfície dos elementos dentários selecionados (SD) e em outra etapa da pesquisa sob o acetato sem a emulsão de prata de uma película radiográfica (PR). Três sistemas de radiografia digital realizaram a captura da imagem, em seus respectivos softwares realizou-se as medidas: a) sem calibração, b) com padrão de calibração de 5mm e c) com padrão de calibração de 10mm. Quatro observadores previamente instruídos realizaram as medidas. Os resultados foram submetidos a analise estatística de ANOVA seguida pelo método de Tukey a 5%, se obteve diferenças estatísticas, as quais representaram. O tamanho e a localização do padrão metálico interferiram nos resultados; não houve diferença entre as medidas inter-observadores; o software DBSWIN (VistaScan) e VixWin PRO (Visualix) foram os que apresentaram maior diferença entre as medidas. / The technological progresses in digital radiology provide every day new information and applications of this systems, become an indispensable tool for the communication and administration of information among professionals and patient. The aim of this study was compare the correlation factor of the measure tool on three different systems of digital dental x-ray, in maxilla of dry craniums, in the area of pre molars, where the natural influence of vertical angles exists, to evaluate the degree of reliability of the measure tool, with the patterns of arranged calibration in different local, when these measured they be accomplished in the maxilla. For this study 10 superior pre molars was selected, which were extracted of its alveoli for obtaining the Gold Standard (GS) with aid of a digital pachymeter. Metallic patterns were used for the accomplishment of the gauged measures, of 5mm and of 10mm, these were located under the surface of the elements dental selects (SD) and in other stage of the research under the acetate without the emulsion of silver of a film (PR). Three systems of digital x-ray accomplished the capture of the image in its respective softwares, they took place the measures: a) without calibration, b) with pattern of calibration of 5mm and c) with pattern of calibration of 10mm. 4 observers previously well educated accomplished the measures. The results were submitted an statistics analyzes ANOVA proceeded by the method of Tukey at 5%, it was obtained statistical differences. The length and the location of the standard metallic step in on the results; there was no difference among the observers measures; the software DBSWIN (VistaScan) and VixWin PRO (Visualix) have been presented more difference among the measures.
147

Médecine futur antérieur ou les perspectives d'avenir inspirées par deux grandes découvertes scientifiques du XIXe siècle : la théorie microbienne et les rayons X /

Balcerowiak, Stéphane, January 1900 (has links)
Thesis (doctoral)--Université de Reims, 2003. / Title from Summary page ; description based on resource as of 2005-06-17. Includes bibliographical references and index.
148

Avaliação dos recursos de mensuração em diferentes sistemas de radiografia digital / Evaluation of the mensurement resources in different systems of digital x-ray

Angelica Maria Hernandez 09 March 2009 (has links)
Os avanços tecnológicos na área de radiologia digital proporcionam a cada dia novas informações e aplicações de seus sistemas, tornando-se assim ferramenta indispensável para a comunicação e administração de informações entre profissionais e pacientes. A proposta neste estudo foi comparar o fator de correção da ferramenta de medida de três diferentes sistemas de radiografia dentária digital, em maxila de crânios secos, na região de pré-molares, onde existe a influência natural de ângulos verticais, para avaliar o grau de confiabilidade da ferramenta de mensuração, com os padrões de calibração, quando estas medidas forem realizadas na maxila. Para este estudo foram selecionados 10 pré-molares superiores, os quais foram extraídos de seus alvéolos para obtenção do Padrão Ouro (PO) com auxílio de um paquímetro digital. Padrões metálicos foram utilizados para a realização das medidas calibradas, de 5mm e de 10mm, estes localizaram-se sob a superfície dos elementos dentários selecionados (SD) e em outra etapa da pesquisa sob o acetato sem a emulsão de prata de uma película radiográfica (PR). Três sistemas de radiografia digital realizaram a captura da imagem, em seus respectivos softwares realizou-se as medidas: a) sem calibração, b) com padrão de calibração de 5mm e c) com padrão de calibração de 10mm. Quatro observadores previamente instruídos realizaram as medidas. Os resultados foram submetidos a analise estatística de ANOVA seguida pelo método de Tukey a 5%, se obteve diferenças estatísticas, as quais representaram. O tamanho e a localização do padrão metálico interferiram nos resultados; não houve diferença entre as medidas inter-observadores; o software DBSWIN (VistaScan) e VixWin PRO (Visualix) foram os que apresentaram maior diferença entre as medidas. / The technological progresses in digital radiology provide every day new information and applications of this systems, become an indispensable tool for the communication and administration of information among professionals and patient. The aim of this study was compare the correlation factor of the measure tool on three different systems of digital dental x-ray, in maxilla of dry craniums, in the area of pre molars, where the natural influence of vertical angles exists, to evaluate the degree of reliability of the measure tool, with the patterns of arranged calibration in different local, when these measured they be accomplished in the maxilla. For this study 10 superior pre molars was selected, which were extracted of its alveoli for obtaining the Gold Standard (GS) with aid of a digital pachymeter. Metallic patterns were used for the accomplishment of the gauged measures, of 5mm and of 10mm, these were located under the surface of the elements dental selects (SD) and in other stage of the research under the acetate without the emulsion of silver of a film (PR). Three systems of digital x-ray accomplished the capture of the image in its respective softwares, they took place the measures: a) without calibration, b) with pattern of calibration of 5mm and c) with pattern of calibration of 10mm. 4 observers previously well educated accomplished the measures. The results were submitted an statistics analyzes ANOVA proceeded by the method of Tukey at 5%, it was obtained statistical differences. The length and the location of the standard metallic step in on the results; there was no difference among the observers measures; the software DBSWIN (VistaScan) and VixWin PRO (Visualix) have been presented more difference among the measures.
149

The Impact of Breast Cancer Molecular Imaging on the Education and Certification of the Radiologic Technologist.

Botelho, Sarah 01 January 2006 (has links)
Molecular imaging is paving the way to the future of breast cancer detection. Compared to mammography, breast cancer molecular imaging provides a more sensitive, faster, and effective way to detect breast cancer on a cellular level rather than on a gross level. Traditional imaging technologies like mammography detect breast cancer by imaging the morphological changes caused by the disease. In contrast, breast cancer molecular imaging detects the molecular processes in the body that may develop into a disease. Imaging on the cellular level allows for the detection of cancer in its pre-disease state before it actually becomes breast cancer. This study examined the education and certification of radiologic technologists to determine if these processes are keeping pace with the shift in imaging technology. This was accomplished by examining the tasks performed by radiologic technologists during breast cancer molecular imaging in relation to the current education and certification requirements. Questionnaires were sent out to radiologic technologists regarding the education and training they received in order to perform the tasks associated with breast cancer molecular imaging. The American Society of Radiologic Technologists (ASRT) and American Registry of Radiologic Technologists (ARRT) were contacted to obtain information about their current and future plans regarding the impact of molecular imaging on the education and certification of radiologic technologists. The data revealed that the radiologic technologists performing molecular imaging procedures were trained on the job, and that performing breast cancer molecular imaging required a level of know ledge and skills that exceed the levels of the current curriculum guides and certification content specifications. The ARRT has appointed a committee to investigate the need for advanced certification in molecular imaging. The curriculum guides developed by the ASRT do not include content pertaining to molecular imaging procedures. The ASRT is planning to incorporate molecular imaging into the entry level radiography curriculum, as well as into the advanced imaging modalities curriculum guides. The deciding factor on whether molecular imaging will become a completely separate imaging modality or become integrated into existing curriculum guides will depend on the finding of the ARRT and its collaboration with the ASRT.
150

New MRI contrast agents through spin exchange optical pumping of noble gases with a nuclear electric quadrupole moment

Six, Joseph January 2014 (has links)
Hyperpolarized 83Kr has previously demonstrated MRI contrast that is sensitive to the chemical composition of the surface in a porous model system. One-dimensional nuclear magnetic resonance spectroscopy of hyperpolarized 83Kr has also revealed distinctive longitudinal relaxation times from selected regions of an ex vivo rat lung originating from differences in surface to volume ratio. However, at the time, MRI using longitudinal relaxation for contrast was not attempted due to limited signal intensities. Methodological advances of the spin exchange optical pumping process have led to a substantial increase in the 83Kr hyperpolarization and the resulting signal intensity. This methodology originates from a below-ambient pressure hyperpolarization technique explored and developed in this work. Using the improved methodology for spin exchange optical pumping of isotopically enriched 83Kr has resolved anatomical details of ex vivo rodent lungs using hyperpolarized 83Kr MRI for the first time. Different 83Kr longitudinal relaxation times were found between the main bronchi and the parenchymal regions of the lung. The T1 weighted hyperpolarized 83Kr MRI provided the first demonstration of surface quadrupolar relaxation pulmonary MRI contrast. Novel hyperpolarization techniques of 129Xe have also been explored resulting a study into the combustion process of methane. Using 129Xe as a probe into the combustion process permitted the first in situ MRI of combustion and enabled spatial-velocity profiles.

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