• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1514
  • 787
  • 125
  • 101
  • 87
  • 53
  • 51
  • 47
  • 45
  • 22
  • 15
  • 15
  • 15
  • 15
  • 15
  • Tagged with
  • 3004
  • 1272
  • 813
  • 604
  • 532
  • 515
  • 450
  • 394
  • 361
  • 264
  • 233
  • 189
  • 188
  • 186
  • 180
  • 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.
21

Diagnostik und operative Behandlung des Rectumcarcinoms

Rostek, Wolfgang, January 1979 (has links)
Thesis (doctoral)--Ludwig Maximilians-Universität zu München, 1979.
22

Expressão imunohistoquimica de citoqueratinas e actina de musculo liso em carcinomas mucoepidermoides de glandulas salivares em suas diferentes gradações histologicas / Immunohistochemical expression of cytokeratins and smooth muscle actin in salivary gland mucoepidermoid carcinomas in its differents histologic gradings of malignancy

Azevedo, Rebeca de Souza, 1980- 26 February 2007 (has links)
Orientador: Fabio Ramoa Pires / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-08T12:19:16Z (GMT). No. of bitstreams: 1 Azevedo_RebecadeSouza_M.pdf: 4868074 bytes, checksum: 58d90f52fd964c01b78efa26a4a55ae8 (MD5) Previous issue date: 2007 / Resumo: O carcinoma mucoepidermóide (CME) é a neoplasia maligna de glândulas salivares mais comum, apresentando grande diversidade de tipos celulares e histogênese incerta e controversa. O objetivo deste trabalho foi avaliar a expressão imunohistoquímica de citoqueratinas (CKs) de epitélios simples (CKs 7, 8, 18 e 19) e de epitélios complexos (CKs 6, 13 e 14) e de um marcador de diferenciação mioepitelial (actina de músculo liso - AML) em CMEs de glândulas salivares maiores e menores nas diferentes gradações histológicas, na tentativa de estabelecer correlação entre a imunopositividade das células tumorais e o processo de diferenciação e histogênese. Foram selecionados 80 casos de CMEs de glândulas salivares do Departamento de Cirurgia de Cabeça e Pescoço e Otorrinolaringologia do Hospital do Câncer/A.C. Camargo, São Paulo, entre 1957 e 1997. Os locais mais acometidos foram parótida (47,5%) e palato (26,3%). Do total, 45% dos casos foram classificados como de alto grau, 44% de baixo grau, e somente 11% de grau intermediário de malignidade. Células escamosas estavam presentes em 98% dos casos, intermediárias em 71%, mucosas em 54%, claras em 30%, colunares em 29% e oncocíticas em 3%. O padrão de crescimento neoplásico mostrou proporção similar entre os arranjos sólido (89%) e cístico/ductal (81%). A expressão das CKs variou de acordo com o tipo celular: células escamosas apresentaram alta expressão de CKs 6, 7, 8, 14, 18 e 19; células intermediárias de CKs 6, 7 e 8; células mucosas somente de CK7; células claras de CKs 6, 7 e 8; e células colunares de CKs 6, 7, 8 e 18. A CK13 mostrou expressão reduzida em todos os tipos celulares. Diferenciação mioepitelial, embora infreqüente, foi mais observada nas células escamosas e intermediárias. Nas glândulas salivares normais adjacentes, ácinos serosos e mucosos apresentaram alta expressão imunohistoquímica de CK18; ductos intercalados de CKs 6, 7, 18 e 19; ductos estriados de CKs 6, 7, 8, 13, 18 e 19; células ductais excretoras de CKs 6, 7, 8, 18 e 19; células basais excretoras de CK14; e células mioepiteliais de AML e CK14. A grande variedade de tipos celulares associada à expressão imunohistoquímica de diferentes CKs e em menor proporção de AML, similar aos ductos excretores, reforça o conceito de origem do CME a partir de células indiferenciadas pluripotentes localizadas nos ductos excretores das glândulas salivares normais / Abstract: Mucoepidermoid carcinoma (MEC) is the most common malignat salivary gland tumor, composed of several different cell types, with unsettled and controversial histogenesis. The purpose of this study was to analyze the immunohistochemical expression of cytokeratins (CKs) of simple epithelia (7, 8, 18 and 19) and stratified epithelia (6, 13 and 14) and a myoepithelial marker (smooth muscle actin - SMA) â?¿in MECs from major and minor salivary glands in their different histological grading, in order to establish a correlation between tumor cells immunostain and MEC histogenesis and differentiation. Eighty cases of salivary gland MECs retrieved from the Department of Head and Neck Surgery and Otorhinolaryngology/A.C. Camargo Cancer Hospital, São Paulo, Brazil, from 1957 to 1997, were selected. The most common sites were parotid (47,5%) and palate (26,3%). From the total, 45% of the cases were classified as high grade, 44% as low grade, and only 11% as intermediate grade. Squamous cells were present in 98% of the cases, intermediate cells in 71%, mucous cells in 54%, clear cells in 30%, columnar cells in 29% and oncocytic cells in 3%. Tumor organization showed similar amount of solid nests (89%) and cystic structures or duct-like elements (81%). Cytokeratin expression was variable according to the cellular type: squamous cells presented high expression of CKs 6, 7, 8, 14, 18 and 19; intermediate cells of CKs 6, 7 and 8; mucous cells only of CK7; clear cells of CKs 6, 7 and 8; and columnar cells of CKs 6, 7, 8 and 18. CK13 was infrequently expressed in all cell types. Myoepithelial expression, albeit uncommon, was more frequently observed in squamous and intermediate cells. In normal salivary gland tissue found adjacent to the tumors, serous and mucous acini showed high immunohistochemical expression of CK18; intercalated ducts of CKs 6, 7, 18 and 19; striated ducts of CKs 6, 7, 8, 13, 18 and 19; ductal cells of excretory ducts of CKs 6, 7, 8, 18 and 19; basal cells of excretory ducts of CK14; and myoepithelial cells of SMA and CK14. The diversity of cellular types associated to the immunohistochemical expression of different CKs and, in less amount of SMA, similarly to excretory ducts reinforces the concept of MEC origin from pluripotential cells localized at the excretory ducts of normal salivary glands / Mestrado / Estomatologia / Mestre em Estomatopatologia
23

Expressão da acido graxo sintase, ErbB-2, p27 E Skp2 na carinogenese bucal induzida por 1-oxido 4-nitroquinolina em camundongos e efeito antitumoral do Orlistat / Fatty Acid Sintase, ErbB-2, p27 E Skp2 expression in oral carcinogenesis induced by 4-nitroquinoline 1-oxide and antitumoral Orlistat effects

Campagnoli, Eduardo Bauml 28 August 2007 (has links)
Orientador: Jacks Jorge Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-09T19:48:28Z (GMT). No. of bitstreams: 1 Campagnoli_EduardoBauml_D.pdf: 15962845 bytes, checksum: 0ed7f5d5b20c8803dc7f1a23bf3b1d5d (MD5) Previous issue date: 2007 / Resumo: O carcinoma espinocelular de boca é um dos cânceres mais comuns do mundo, logo a compreensão das vias moleculares envolvidas no processo de carcinogênese poderá auxiliar no desenvolvimento de drogas para o tratamento e prevenção deste tipo de neoplasia. FAS é uma das enzimas metabólicas que participam da síntese endógena de ácidos graxos, enquanto ErbB-2 é um receptor de membrana celular responsável pelo crescimento e diferenciação de vários tipos celulares. Já a proteína p27 é inibidora do ciclo celular e Skp2 é uma ubiquitina ligase que atua na ubiquitinização e degradação de p27. Estudos têm demonstrado que a inibição da FAS desencadeia o processo de apoptose em diversas linhagens de células neoplásicas. Recentemente relatou-se que o Orlistat apresenta efeito inibitório sobre a FAS. Portanto, o objetivo deste estudo foi comparar a expressão de FAS, ErbB-2, p27 e Skp2 em epitélios com displasia leve, moderada, severa e no carcinoma espinocelular quimicamente induzidos, bem como verificar o efeito do Orlistat no processo de carcinogênese bucal. Para tanto, camundongos foram expostos ao 1-óxido 4-nitroquinolina (4NQO) durante 16 semanas e sacrificados ao completarem 16, 18, 20 e 25 semanas. Um dos grupos também recebeu injeção intraperitonial de Orlistat (240 mg/kg) diária, durante quinze dias. Após o sacrifício dos animais, a língua foi removida, emblocada em parafina e cortes histológicos obtidos. Presença de displasias e neoplasias malignas foram avaliadas em lâminas coradas por hematoxilina e eosina. Reações imunohistoquímicas foram realizadas com os anticorpos: Ki-67 (marcador de proliferação celular), FAS, ErbB-2, p27 e Skp2. O índice de proliferação celular (Ki-67) foi de 26,57%, 22,85%, 26,12% e 23,86% nas áreas de displasia leve, moderada, severa e carcinoma invasivo, respectivamente. O epitélio normal teve índice de proliferação celular de 4,31%. ErbB-2 exibiu aumento na expressão tanto nas áreas displásicas como tumorais, sendo que ambas apresentaram mais de 50% de células imunomarcadas. Aumento na expressão da FAS diferiu de modo estatisticamente significante, em relação ao epitélio normal, somente nas áreas com displasia severa e de carcinoma invasivo, embora aumento gradual na expressão desta proteína tenha sido observado durante todo o processo de carcinogênese. A quantidade protéica de p27 aumentou gradualmente durante a carcinogênese, sendo as maiores taxas encontradas nas áreas de displasia severa (57,50% de células imunomarcadas) e carcinoma invasivo (53,55% de células positivas). Para Skp2 verificou-se imunomarcação exclusivamente citoplasmática (Skp2-B), a qual esteve aumentada tanto nas áreas displásicas como tumorais. Os camundongos tratados com Orlistat tiveram área tumoral 67,25% menor do que os animais não tratados. Além disso, houve diminuição na proliferação celular (2,58% de positividade celular), bem como menor número de células imunomarcadas contra as proteínas p27 e Skp2-B. Com base nesses resultados concluiu-se que durante o processo de carcinogênese bucal induzida por 4NQO houve aumento na proliferação celular (Ki-67) e na expressão das proteínas FAS, ErbB-2, p27 e Skp2-B (citoplasmática), sendo que ErbB-2 e Skp2-B tiveram aumento significativo já nos estágios iniciais da carcinogênese. Além disso, o Orlistat apresentou efeito antitumoral e antiproliferativo em carcinomas espinocelulares de língua quimicamente induzidos / Abstract: Squamous cell carcinoma of the oral cavity is one of the most common malignant epithelial neoplasms, and a better understanding of its molecular pathways could help the development of new treatment or preventive agents. Several proteins such as Fatty Acid Synthase (FAS), ErbB-2, p27 and Skp2 are involved in the tumorigenesis process. FAS has an enzyme with multiple functions, including the endogenous synthesis of saturated fatty acids. ErbB-2 is a transmembrane receptor that may have a role in cellular growth and differentiation. p27 is a cyclin-dependent kinase inhibitor and plays an important role on the negative regulation of the cell cycle. On the other hand, Skp2 is an ubiquitin ligase that targets p27 for ubiquitination and degradation. Studies have demonstrated that FAS inhibition induces apoptosis in various neoplastic cells and can suppress tumor cell proliferation. It has been demonstrated that Orlistat has anti-proliferative and anti-tumor properties through blocked FAS activity. Therefore, the aim of the present study was to investigate FAS, ErbB-2, p27 and Skp2 expression in the epithelium with chemically-induced dysplasia and squamous cell carcinoma, and to verify the effect of Orlistat on the carcinogenic process. Lesions were induced by 4NQO in the drinking water to C57BL/6 mice during 16 weeks. The animals were sacrificed after 16, 18, 20 and 25 weeks of treatment. One group also received intraperitonial injection of Orlistat, 240 mg/kg/day, during fifteen days. The tongues were removed and paraffin embedded tissues were cut and stained with hematoxylin and eosin. Dysplastic lesions and squamous cell carcinomas were analyzed in slides stained with hematoxylin and eosin. Immunohistochemistry assays were performed for Ki-67, FAS, ErbB-2, p27 and Skp2. The percentage of cells that reacted with the Ki-67 antibody was 26.57%, 22.85%, 26.12% and 23.86% in areas with mild, moderate, severe dysplasia and invasive carcinoma, respectively. The normal epithelium had low index of cellular proliferation, 4.31%. ErbB-2 showed increase in the expression in dysplastic and tumor areas, for both presented more 50% of positive cells. High expression of FAS was observed in areas with severe dysplasia and squamous cell carcinoma, although gradual increased was observed during all the carcinogenic process. Expression of p27 protein increased gradually during carcinogenesis and the biggest levels were detected in areas with severe dysplasia (57.50% of immunostaining cells) and invasive carcinoma (53.55% of positive cells). Skp2 immunoexpression was strictly cytoplasmic (Skp2-B), and it was increased in tumoral and dysplastic areas. Lesions of mice treated with Orlistat showed a 67.25% reduction when compared with non-treated animals. Moreover, cellular proliferation was reduced (2.58% of cellular immunostaining), and there were less cells immunostained for p27 and Skp2-B. Therefore dysplastic areas showed increased expression of Ki-67 and high expression of FAS, ErbB-2, p27 and Skp2-B, when compared with normal epithelium. ErbB-2 and Skp2-B had increased expression in the early stages of carcinogenesis. Moreover, Orlistat showed anti-tumoral and anti-proliferative effect in chemically-induced quamous cell carcinomas of the tongue / Doutorado / Estomatologia / Doutor em Estomatopatologia
24

The In Vitro Characterization of a Squamous Carcinoma Cell Line to Combined Treatment with Cisplatin and Ionizing Radiation / In Vitro Characterization of Squamous Carcinoma Cells to Cisplatin and Radiation

Caney, Colleen January 1996 (has links)
It is has been observed in several cell systems that cisplatin can radiosensitize and that the response of cells to combination cisplatin and radiation depends on several factors. These include the radiation dose and drug concentration used, the order in which the two treatments are administered, and the time between their administration. The response of a head and neck squamous carcinoma cell line to combination cisplatin-radiation treatment was examined. The response was found to be additive when cisplatin was given first, regardless of the timing and magnitude of the treatments administered. When cells were treated with radiation first, antagonism was observed for low radiation doses and drug concentrations. The response may be explained by a low radiation dose induction of processes that protect the cell from a second damaging agent, similar to the adaptive response. There is some indication in the literature that cisplatin can preferentially radiosensitize cells that are proficient in certain types of DNA repair. Therefore, the response of a cisplatin-resistant strain of the SCC-25 cell line was also investigated. The cisplatin-resistant cell line was found to be substantially radiosensitized by cisplatin for moderate amounts of radiation and cisplatin. The results are discussed with reference to the current proposed mechanisms for cisplatin-radiation interaction. / Thesis / Master of Science (MS)
25

The prognostic significance of DJ-1 in patients with renal cell carcinoma of clear cell type

Lee, Wing-sang., 李榮生. January 2009 (has links)
published_or_final_version / Pathology / Master / Master of Medical Sciences
26

Gene expression profiles of Papillary and Anaplastic Thyroid Carcinomas

Delys, Laurent 27 November 2007 (has links)
Les tumeurs thyroïdiennes constituent les tumeurs endocrines les plus fréquentes. Parmi celles-ci, on distingue les adénomes, tumeurs bénignes et encapsulées, et les carcinomes, tumeurs malignes. Ceux-ci sont eux-mêmes subdivisés, principalement sur base histologique, en carcinomes papillaires ou folliculaires, qui conservent certaines caractéristiques de différenciation des cellules thyroïdiennes initiales dont ils dérivent, et qui peuvent évoluer en carcinomes anaplasiques, totalement dédifférenciés. Les carcinomes différenciés de la thyroïde sont généralement de bon pronostic, contrairement aux cancers anaplasiques qui sont nettement plus agressifs, avec un taux de survie à 5 ans inférieur à 5%. La technologie des microarrays permet d’analyser simultanément l’expression de milliers de gènes dans différentes cellules et différentes conditions physiologiques, pathologiques ou toxicologiques. Au cours de cette thèse de doctorat, nous avons déterminé le profil d’expression génique des carcinomes papillaires de la thyroïde à l’aide de la technique des microarrays en utilisant une plateforme contenant plus de 8000 gènes. Douze des 26 cancers papillaires étudiés étaient issus de patients habitant la région de Tchernobyl lors de l’explosion de la centrale nucléaire de 1986 et sont considérés comme des cancers radio-induits. Les 14 tumeurs restantes proviennent de patients habitant la France. Leur étiologie n’étant pas connue, ils sont considérés comme des cancers sporadiques. La réalisation de ces expériences nous a permis d’identifier des signatures moléculaires entre des sous-types de cancers papillaires. Premièrement, nous avons montré que malgré un profil d’expression génique global similaire entre les cancers papillaires sporadiques et radio-induits, une signature multigénique permet de les séparer, indiquant que des subtiles différences existent entre les deux types de tumeurs. Deux autres signatures indépendantes, l’une liée aux agents étiologiques présumés de ces tumeurs (radiation vs. H2O2), l’autre liée aux mécanismes de recombinaison homologue de l’ADN, permettent également de séparer les cancers post-Tchernobyl des cancers sporadiques. Nous avons interprété ces résultats comme une différence de susceptibilité à l’irradiation entre ces deux types de tumeurs. D’autre part, nous avons pu identifier une liste de gènes permettant de séparer les cancers papillaires à variante classique des autres sous-types de cancers papillaires. L’analyse de cette liste de gènes a permis de mettre en relation cette signature avec l’important remodelage de cette variante histologique par rapport aux autres. Ces expériences ont aussi abouti à l’obtention d’une liste de gènes différentiellement exprimés entre les cancers papillaires et leur tissu normal adjacent. Une analyse minutieuse de cette liste à l’aide d’outils statistiques a permis de mieux comprendre la physiopathologie de ces tumeurs et d’aboutir à différentes conclusions : (1) un changement de population cellulaire est observé, avec une surexpression de gènes liés à la réponse immune, reflétant l’infiltration lymphocytaire de ces tumeurs par rapport au tissu normal adjacent (2) la voie de signalisation JNK est activée par surexpression de ses composants (3) la voie de signalisation de l’EGF, également par une surexpression de ses composants, complémente les altérations génétiques des cancers papillaires pour l’activation constitutive de la voie ERK1/2 (4) une sousexpression des gènes de réponse précoce est observée (5) une surexpression de nombreuses protéases, d’inhibiteurs de protéases et de protéines de la matrice extracellulaire permet d’expliquer l’important remodelage des cancers papillaires (6) le profil d’expression génique des cancers papillaires peut être corrélé avec un mode de migration collectif de ces tumeurs. Finalement, dans la dernière partie de la thèse, nous avons déterminé le profil d’expression génique des cancers anaplasiques de la thyroïde et l’avons comparé à celui des cancers papillaires. Nous avons montré que les deux types de tumeurs présentent des profils moléculaires globaux distincts, reflétant leur comportement tumoral très différent.
27

The measurement of urinary #beta# core in women with lower genital tract cancer and its prognostic significance

Carter, Paul Gareth January 1998 (has links)
No description available.
28

Studies on human papillomavirus type 16

Browne, Helena Margaret January 1987 (has links)
No description available.
29

The role of interferon gamma and other cytokines in the antitumour activity of interleukin 12

Gri, Giorgia January 2002 (has links)
No description available.
30

Molecular analysis of DNA damage induced by a novel trinuclear platinum complex (BBR 3464)

Colella, Gennaro Giovanni Domenico January 2001 (has links)
No description available.

Page generated in 0.0415 seconds