• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 2
  • 1
  • Tagged with
  • 6
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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.
1

Realce de fundo do tecido fibroglandular da mama contralateral como preditor de resposta ao tratamento quimioterápico neoadjuvante do carcinoma ductal invasivo localmente avançado / Backgroud parenchymal enhancement of the contralateral breast as predictor of response to neoadjuvant chemotherapy for locally advanced invasive ductal carcinoma

Costa, Denise Maria Zeoti Bueno da 01 July 2016 (has links)
Introdução: A neoplasia de mama é o tipo mais comum de câncer entre as mulheres. A despeito dos programas de rastreamento, que marcadamente reduziram a mortalidade, devido, principalmente ao diagnóstico precoce, uma significativa parcela de mulheres, apresenta-se com tumores localmente avançados na ocasião do diagnóstico. Nestas situações o tratamento neoadjuvante (TNA) está indicado. Com o advento de novos esquemas medicamentosos e crescentes indicações de TNA, busca-se fatores preditores da resposta tumoral, que a determinem de maneira precoce, precisa, objetiva e reprodutível. Até o momento, não há consenso em como determinar, clinicamente, a resposta da neoplasia ao TNA. Objetivo: O presente estudo investigou a associação entre o realce de fundo do tecido fibroglandular (BPE) em exames de RM da mama contralateral a neoplasia e a resposta patológica ao tratamento quimioterápico neoadjuvante (TNA), em pacientes portadoras de câncer de mama localmente avançado. Materiais e Métodos: Um total de 55 pacientes apresentando carcinoma ductal invasivo de mamas foram avaliadas, consecutivamente, entre setembro de 2010 e novembro de 2013. As pacientes selecionadas realizaram RM previamente ao início do tratamento quimioterápico e foram submetidas a tratamento cirúrgico após término do TNA. O BPE foi aferido através da avaliação qualitativa, de acordo com as categorias preconizadas pela 5° edição do BI-RADS e por método quantitativo, por segmentação automática do tecido fibroglandular da mama contralateral a neoplasia e cálculo do coeficiente de realce do parênquima. As pacientes foram divididas em dois grupos, de acordo com os achados anatomopatológicos encontrados na peça cirúrgica obtida ao término do TNA: Grupo Resposta Completa: ausência de neoplasia na peça cirúrgica e Grupo Resposta Ausente: presença de neoplasia residual na peça cirúrgica. O BPE destes dois grupos foi então comparado. Resultados: Encontramos diferença significativa (p<0,001) entre os grupos para a variável BPE, quando aferida de maneira qualitativa, sendo que o grupo que obteve resposta patológica completa apresentou maior BPE. A análise do coeficiente do BPE não demonstrou diferença significativa entre os grupos (p=0,075), porém uma tendência a diferença significativa, com o grupo resposta patológica completa apresentando valores superiores de coeficiente de realce, em concordância com a avaliação qualitativa. Conclusões: Os resultados sugerem que o BPE da mama contralateral à neoplasia pode estar relacionado à resposta patológica após TNA, quando aferido de maneira qualitativa. Maiores valores de coeficiente de BPE também parecem estar associados a maior chance de obter resposta patológica completa. / Introduction: Breast cancer is the most common type of cancer among women. Despite screening programs, which markedly reduced mortality mainly due to early diagnosis, a significant number of women present with locally advanced tumors at diagnosis. The neoadjuvant chemotherapy treatment (NAT) is indicated in these situations. The advent of new drug regimens and growing indications of NAT requires biomarkers for assessing and predicting the response of breast cancer to neoadjuvant therapy. At presente, there is no consensus to the early assessment of breast cancer response to NAT. Objective: This study investigated the association between Backgroud Parenchymal Enhancement (BPE) of contralateral breast cancer and the pathologic response to neoadjuvant chemotherapy treatment in patients with locally advanced breast cancer. Materials and Methods: A retrospective study of 55 patients with locally advanced breast cancer. The selected patients underwent MRI before the start of chemotherapy and underwent surgery after TNA completion. The BPE was determined by qualitative assessment, according to the categories recommended by the 5th edition of BI- RADS, and quantitative method by automatic segmentation of fibroglandular tissue of contralateral breast and calculation of BPE coefficient. The patients were divided into two groups according to pathological findings in surgical specimens obtained at the end of TNA, Group Complete Response: no tumor in the surgical specimen and Group Response Absent: presence of residual tumor in the surgical specimen .The BPE of these two groups were compared. Results: We found a significant difference (p <0.001) between the groups for the BPE variable when measured in a qualitative manner. The complete pathological response group got highest category of BPE. The analysis of the BPE coefficient showed no significant difference between groups (p=0.075), but a tendency to significant differences, with complete pathological response group presenting higher values of BPE coefficient. Conclusions: The results suggest that the BPE of contralateral breast is correlated to the pathological response after neoadjuvant chemotherapy treatment, when measured in a qualitative manner. Higher values of BPE coefficient appear to be associated with a higher chance of getting complete pathological response to neoadjuvant chemotherapy treatment.
2

Realce de fundo do tecido fibroglandular da mama contralateral como preditor de resposta ao tratamento quimioterápico neoadjuvante do carcinoma ductal invasivo localmente avançado / Backgroud parenchymal enhancement of the contralateral breast as predictor of response to neoadjuvant chemotherapy for locally advanced invasive ductal carcinoma

Denise Maria Zeoti Bueno da Costa 01 July 2016 (has links)
Introdução: A neoplasia de mama é o tipo mais comum de câncer entre as mulheres. A despeito dos programas de rastreamento, que marcadamente reduziram a mortalidade, devido, principalmente ao diagnóstico precoce, uma significativa parcela de mulheres, apresenta-se com tumores localmente avançados na ocasião do diagnóstico. Nestas situações o tratamento neoadjuvante (TNA) está indicado. Com o advento de novos esquemas medicamentosos e crescentes indicações de TNA, busca-se fatores preditores da resposta tumoral, que a determinem de maneira precoce, precisa, objetiva e reprodutível. Até o momento, não há consenso em como determinar, clinicamente, a resposta da neoplasia ao TNA. Objetivo: O presente estudo investigou a associação entre o realce de fundo do tecido fibroglandular (BPE) em exames de RM da mama contralateral a neoplasia e a resposta patológica ao tratamento quimioterápico neoadjuvante (TNA), em pacientes portadoras de câncer de mama localmente avançado. Materiais e Métodos: Um total de 55 pacientes apresentando carcinoma ductal invasivo de mamas foram avaliadas, consecutivamente, entre setembro de 2010 e novembro de 2013. As pacientes selecionadas realizaram RM previamente ao início do tratamento quimioterápico e foram submetidas a tratamento cirúrgico após término do TNA. O BPE foi aferido através da avaliação qualitativa, de acordo com as categorias preconizadas pela 5° edição do BI-RADS e por método quantitativo, por segmentação automática do tecido fibroglandular da mama contralateral a neoplasia e cálculo do coeficiente de realce do parênquima. As pacientes foram divididas em dois grupos, de acordo com os achados anatomopatológicos encontrados na peça cirúrgica obtida ao término do TNA: Grupo Resposta Completa: ausência de neoplasia na peça cirúrgica e Grupo Resposta Ausente: presença de neoplasia residual na peça cirúrgica. O BPE destes dois grupos foi então comparado. Resultados: Encontramos diferença significativa (p<0,001) entre os grupos para a variável BPE, quando aferida de maneira qualitativa, sendo que o grupo que obteve resposta patológica completa apresentou maior BPE. A análise do coeficiente do BPE não demonstrou diferença significativa entre os grupos (p=0,075), porém uma tendência a diferença significativa, com o grupo resposta patológica completa apresentando valores superiores de coeficiente de realce, em concordância com a avaliação qualitativa. Conclusões: Os resultados sugerem que o BPE da mama contralateral à neoplasia pode estar relacionado à resposta patológica após TNA, quando aferido de maneira qualitativa. Maiores valores de coeficiente de BPE também parecem estar associados a maior chance de obter resposta patológica completa. / Introduction: Breast cancer is the most common type of cancer among women. Despite screening programs, which markedly reduced mortality mainly due to early diagnosis, a significant number of women present with locally advanced tumors at diagnosis. The neoadjuvant chemotherapy treatment (NAT) is indicated in these situations. The advent of new drug regimens and growing indications of NAT requires biomarkers for assessing and predicting the response of breast cancer to neoadjuvant therapy. At presente, there is no consensus to the early assessment of breast cancer response to NAT. Objective: This study investigated the association between Backgroud Parenchymal Enhancement (BPE) of contralateral breast cancer and the pathologic response to neoadjuvant chemotherapy treatment in patients with locally advanced breast cancer. Materials and Methods: A retrospective study of 55 patients with locally advanced breast cancer. The selected patients underwent MRI before the start of chemotherapy and underwent surgery after TNA completion. The BPE was determined by qualitative assessment, according to the categories recommended by the 5th edition of BI- RADS, and quantitative method by automatic segmentation of fibroglandular tissue of contralateral breast and calculation of BPE coefficient. The patients were divided into two groups according to pathological findings in surgical specimens obtained at the end of TNA, Group Complete Response: no tumor in the surgical specimen and Group Response Absent: presence of residual tumor in the surgical specimen .The BPE of these two groups were compared. Results: We found a significant difference (p <0.001) between the groups for the BPE variable when measured in a qualitative manner. The complete pathological response group got highest category of BPE. The analysis of the BPE coefficient showed no significant difference between groups (p=0.075), but a tendency to significant differences, with complete pathological response group presenting higher values of BPE coefficient. Conclusions: The results suggest that the BPE of contralateral breast is correlated to the pathological response after neoadjuvant chemotherapy treatment, when measured in a qualitative manner. Higher values of BPE coefficient appear to be associated with a higher chance of getting complete pathological response to neoadjuvant chemotherapy treatment.
3

Détection de l'effet de lentille gravitationnelle dans les données de Planck-HFI / Detection of CMB lensing in Planck-HFI data

Lavabre, Alexis 25 May 2011 (has links)
Le satellite Planck est le satellite de troisième génération visant à observer le fond diffus cosmologique. La résolution et la sensibilité de ses instruments permettent pour la première fois de mettre en évidence les effets de lentille gravitationnelle subis par les photons du fond diffus cosmologique. Cette thèse présente une méthode originale de détection de ces effets dans les données de l'instrument HFI de Planck.La première partie donne dans un premier temps, une description générale du modèle standard de la cosmologie et de la physique du fond diffus cosmologique. Elle aborde ensuite en détails l'effet de lentille gravitationnelle, en se concentrant plus particulièrement sur son impact sur les observables du fond diffus cosmologique. Elle termine par une présentation du satellite Planck et de ses instruments.La seconde partie se concentre sur la description d'un ensemble d'outils de simulations et d'analyse que j'ai développé au cours de ma thèse afin de réaliser la première détection des effets de lentille gravitationnelle sur le fond diffus cosmologique. Elle présente la méthode originale employée qui repose sur une analyse des cartes du ciel par morceaux, permettant de s'affranchir des zones du ciel les plus contaminées. On trouvera également dans cette partie une caractérisation, de l'estimateur du champ de potentiel de lentille, pour des cartes masquée, en présence de bruit inhomogène ainsi que la présentation d'une méthode pour corriger les biais de l'analyse à l'aide de simulations Monte-Carlo.La dernière partie, est consacrée au travail sur les données de l'instrument HFI. Le premier chapitre présente l'application de la méthode d'analyse précédente aux cartes des observations combinées à 143GHz et 217GHz ainsi que la carte issue de la séparation des composantes avec l'algorithme GMCA. Les résultats montrent un spectre de puissance de la déflexion compatible avec le spectre attendu, dans un modèle lambda CMB, calculé à partir des paramètres cosmologiques issus de WMAP intégrant sept années d'observations. Les points de mesure, issus du spectre combiné des cartes à 143GHz et 217GHz, pour les multipôles inférieurs à 500, donnent un Chi2 par degré de liberté de 1.26. Finalement, le dernier chapitre présente l'algorithme de compression des données de l'instrument HFI à bord du satellite. Il traite en détail le réglage et le suivi des paramètres de compression et du débit des données, depuis le lancement du satellite et fait le bilan sur les erreurs de compression rencontrées / The Planck satellite is the third generation experement dedicated to the observation of the cosmic microwave backgroud (CMB). The resolution and sensibility of its intruments allow for the first time the detection of the weak lensing effect on CMB. This thesis present a original detection method of this effect in the data of the HFI instrument of Planck.The first part give a general description of the standard model of cosmology et the physics of the CMB. The part then presents the details of the weak lensing effect, concentrating on its impact on the CMB observables. This part ends with a description of the Planck satellite and its instruments.The second part, discribes the set of simulations and analysis tools that I have developed allowding me to make the first mesureament of the weak lensing effect on CMB. It presents the original method that I used which is based on a patch analysis of the full sky data, that is able to only take into account the less contaminated regions. This part also present the caracterisation of the lensing potential estimator for masked maps in the presence of inhomogeneous noise and introduce a method, based on Monte-Carlo simulations, that is used to correct for the biais produced by the analysis method.The last part, concentrates on the work on HFI data. The first chapter presents the application of the above method to the maps of the combined observations at 143GHz and 217GHz and the maps from component separation using GMCA algorithm. The results show a deflection power spectrum compatible with the one expect in a lambda CMB universe, calculated with the cosmological parameters estimated by WMAP including seven years of observations. Using the points, from the combined estimation from the 143GHz and 217GHz maps, for multipole smaller than 500, gives a 1.26 Chi2 by degree of freedom. Finally, the last chapter presents the comression algorithm used onboard to compression HFI data. It gives the details of the tunning and the following of the compression parameters and the data rate, since the launch and summarize the results on the compression errors
4

Odlišení pozadí a pohybujících se objektů ve videosekvenci / Separation of background and moving objects in videosequence

Martincová, Lucia January 2017 (has links)
This diploma thesis deals with separation of backgroud and moving objects in video. Video can be represented as series of frames and each frame represented as low - rank structure - matrix. This thesis describe sparse representation of signals and robust principal component analysis. It also presents and implements algorithms - models for reconstruction of real video.
5

Odlišení pozadí a pohybujících se objektů ve videosekvenci / Separation of background and moving objects in videosequence

Komůrková, Lucia January 2018 (has links)
This diploma thesis deals with separation of backgroud and moving objects in video. Video can be represented as series of frames and each frame represented as low - rank structure - matrix. This thesis describe sparse representation of signals and robust principal component analysis. It also presents and implements algorithms - models for reconstruction of real video.
6

Odlišení pozadí a pohybujících se objektů ve videosekvenci / Separation of background and moving objects in videosequence

Komůrková, Lucia January 2016 (has links)
This diploma thesis deals with separation of backgroud and moving objects in video. Video can be represented as series of frames and each frame represented as low - rank structure - matrix. This thesis describe sparse representation of signals and robust principal component analysis. It also presents and implements algorithms - models for reconstruction of real video.

Page generated in 0.0231 seconds