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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.
1

Factors related to the occurrence of gastric adenocarcinoma subtypes /

Ekström, Anna Mia, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.
2

Adenocarcinoma da próstata = estudo de fatores clinicopatológicos preditivos de progressão bioquímica (PSA) pós-prostatectomia radical / Prostate adenocarcinoma : study predictive clinicopathological factors of biochemical progression (PSA) after radical prostatectomy

Noronha, Marcelo Ramos 17 August 2018 (has links)
Orientadores: Luciana Rodrigues de Meirelles, Athanase Billis / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-17T03:17:56Z (GMT). No. of bitstreams: 1 Noronha_MarceloRamos_M.pdf: 4236927 bytes, checksum: 8e1d5407a5771801d828a3660c398949 (MD5) Previous issue date: 2010 / Resumo: O adenocarcinoma de próstata é a segunda neoplasia maligna que afeta homens, sendo precedida somente pelo cancer de pele. A prostatectomia radical continua sendo a mais aceita estratégia terapêutica para os casos confinado a próstata. Alguns achados clinicopatológicos em pacientes submetidos a prostatectomia radical são controvertidos como tendo valor preditivo de progressão bioquímica pós-cirurgia. O monitoramento da progressão da moléstia pós-prostatectomia radical é feito através de dosagem do PSA sérico cujo aumento pode significar recidiva local e/ou metástases. O valor de corte do PSA sérico indicando progressão é variável entre os autores. Há uma recomendação recente da Associação Americana de Urologia para que este valor seja ?0,2ng/mL com um segundo valor >0,2ng/mL. Não está estabelecido se pacientes mais jovens ou de raça negra mostram taxa de recidiva bioquímica maior. O PSA pré-operatório é um dado de grande importância preditiva, mas não está estabelecido a validade da estratificação dos valores em 3 categorias: 4-10ng/mL, 10-20ng/mL e >20ng/mL. Margens cirúrgicas comprometidas no espécime cirúrgico estão na categoria I (valor preditivo comprovado). É controvertido se a contagem final de Gleason 3+4=7 é semelhante ou não a 4+3=7 como fator preditivo de progressão bioquímica pós-prostatectomia radical. O estudo foi retrospectivo e os dados foram coletados dos prontuários médicos de 300 pacientes submetidos consecutivamente à prostatectomia radical no Hospital de Clínicas da Universidade Estadual de Campinas, no período de janeiro de 1997 a maio de 2007. O objetivo principal do trabalho foi avaliar a progressão bioquímica (PSA) pós prostatectomia radical de acordo com: raça, idade, margens cirúrgicas comprometidas, invasão microscópica do colo vesical, contagem final de Gleason, extensão do tumor, estádio patológico e PSA pré-operatório. Os dados obtidos foram analisados estatisticamente utilizando-se o teste de Mann-Whitney, o produto limite de Kaplan-Meier utilizando-se o teste do log-rank para comparação entre os grupos e o método de Cox para avaliar risco do tempo de progressão bioquímica (PSA) pós-prostatectomia radical. O nível de significância considerado para rejeição da hipótese nula foi p<0,05 bicaudal. Os resultados mais importantes neste trabalho foram: diferença estatisticamente significante quanto ao tempo de progressão bioquímica de pacientes com PSA pré-operatório ?10ng/mL, margens cirúrgicas comprometidas, invasão microscópica do colo vesical, Gleason 4+3=7, tumores mais extensos e tumores não confinados à próstata. Não houve associação da idade e raça com progressão bioquímica. Em análise univariada, os fatores preditivos significantes do tempo e risco de progressão pós-prostatectomia radical foram o PSA pré-operatório, as margens cirúrgicas positivas, a invasão das vesículas seminais, a invasão microscópica do colo vesical e o Gleason 4+3=7. Em análise multivariada, somente PSA pré-operatório, margens positivas e invasão das vesículas seminais mostraram-se fatores preditivos independentes do tempo e risco de progressão bioquímica pós-prostatectomia radical / Abstract: Adenocarcinoma of the prostate is the second malignancy that affects men, being preceded only by skin cancer. Radical prostatectomy remains the most widely accepted treatment strategy for cases confined to the prostate. Some clinical and pathological findings in patients undergoing radical prostatectomy are at issue as having predictive value of biochemical progression after surgery. The monitoring of disease progression after radical prostatectomy is done by measuring concentrations of PSA which can mean increased local recurrence and/or metastases. The cutoff of PSA indicating progression varies among authors. There is a recent recommendation of the American Urological Association that this value is ?0.2ng/mL with a second value >0.2ng/mL. It has not been established whether younger or black patients show higher rate of biochemical recurrence. The preoperative PSA is an important predictive factor for biochemical recurrence, but it has not been established the validity of the stratification of values in three categories: 4-10ng/mL, 10-20ng/mL, and >20ng/mL. Positive surgical margins in the surgical specimen are in category I (proven predictive value). It is controversial whether the final Gleason score 3+4=7 is similar or not to 4+3=7 as a predictor of biochemical progression after radical prostatectomy. The study was based on 300 whole-mount consecutive radical prostatectomies. The aim of this study was to analyse the risk and time for biochemical progression after surgery, according to race, age, positive surgical margins, bladder neck invasion, Gleason score, tumor extension, pathological stage and serum PSA preoperative levels. Time to biochemical progression-free outcome was compared using the Kaplan-Meier product-limit analysis using the log-rank to compare the groups. To assess individual variables for risk and time to biochemical progression, we created a univariate Cox proportional hazards model, and to assess the influence of several variables simultaneously, we developed a final multivariate Cox proportional hazards model of the statistically significant covariates. The most important results were: There was a significant association to time of progression of patients with preoperative PSA ?10ng/mL, positive surgical margins, microscopic invasion of the bladder neck, Gleason 4+3=7, more extensive tumors and non confined tumors. No association of race and age to biochemical progression following radical prostatectomy. On univariate analysis, the significant predictive variables for risk and time to biochemical progression were: preoperative PSA, positive surgical margins, seminal vesicle invasion, microscopic invasion of the bladder neck, and Gleason 4+3=7. On multivariate analysis, only positive surgical margins and seminal vesicle invasion were independent predictive variables / Mestrado / Anatomia Patologica / Mestre em Ciências Médicas
3

Perfil de expresión de la proteína Hras P21 en cáncer gástrico

Aguila Gálvez, Heidi del January 2006 (has links)
Durante el presente siglo, el cáncer ha sido considerado una de las causas más importantes de muerte en todo el mundo; éste ocurre como consecuencia de una desregulación del crecimiento celular normal, usualmente por defectos en los mecanismos de señalización. Las proteínas Ras fueron algunas de las primeras proteínas identificadas que poseen la habilidad de regular el crecimiento celular. Son interruptores moleculares capaces de activar a otras proteínas cuesta abajo en la vía de señalización encabezada por los RTKs, llevando a la proliferación celular. Normalmente, las formas activas e inactivas de la proteína se encuentran, en equilibrio en la célula de manera que mantengan el crecimiento celular normal, sin embargo, en su forma mutada, la actividad GTPásica de la proteína se ve alterada, previniendo que las proteínas GAPs promuevan la hidrólisis del GTP por Ras y por tanto causando que Ras se acumule en su forma activa, unida a GTP. Los mutantes oncogénicos de las proteínas Ras han sido reportados en alrededor de 25 al 30% de los tumores humanos, encontrándose sobre expresada en carcinomas de estómago, cuello uterino, pulmón, células renales, entre otras. En el Perú, una de las neoplasias más frecuentes es la de estómago, llegando a ocupar el segundo lugar en incidencia en Lima Metropolitana, siendo superada únicamente por el cáncer de mama femenino, por lo que resulta importante conocer los mecanismos biológicos que ocurren en dicha neoplasia. Considerando que los trabajos a nivel proteómico son escasos, en la presente investigación se evaluó la expresión de la proteína Hras p21 por métodos inmunohistoquímicos en biopsias de carcinoma y adenocarcinoma gástrico, encontrando inmunorreacción positiva en el 77,78% y 85,71%, respectivamente, distribuida tanto en citoplasma como en membrana plasmática, concluyéndose que la proteína Hras p21 está sobre expresada en cáncer gástrico, presenta un doble perfil de expresión en tejido tumoral, es un factor etiológico importante en el desarrollo de la carcinogénesis gástrica, y podría servir como un marcador tumoral relacionado a cáncer gástrico. / During the present century, cancer has been considered one of the most important reasons of death around the world; it occurs when normal growth regulation breaks down, usually because of defects in these signalling mechanisms. The RAS proteins were some of the first proteins identified that possessed the ability to regulate cell growth. They are molecular switches, which act downstream from most RTKs, leading to cellular proliferation. In the resting cells, the active and inactive forms are in equilibrium, in order to maintain the normal cell growth, however, the Ras mutation compromise its GTPase activity of, preventing GAPs from promoting hydrolysis of GTP on RAS and therefore causing RAS to accumulate in the GTP-bound, active form. Oncogenic mutants of Ras proteins have been found in 25 - 30% of the human tumours. Ras proteins are over expressed in many tumours, such as stomach carcinoma, carcinomas of the uterine cervix, lung carcinoma, renal cells carcinoma. In Perú, one of the most frequents cancers is gastric cancer, it occupies the second place in incidence in Metropolitan Lima after breast cancer; for this reason it’s important to know the biological mechanisms that occur in this disease. Because there are not many research works at the proteomic level, in this investigation, it has been evaluated the expression of Hras p21 protein in gastric biopsy (carcinomas and adenocarcinomas) using inmunohistochemistry, finding a positive staining in 77.78% and 85.71% respectively, localized in cytoplasm and plasma membrane, concluding that Hras p21 is over expressed in gastric cancer, it shows a double expression profile in malignant tissue, and it’s an important ethiological factor for the development of a gastric tumour, and it may be an useful tumour marker related to gastric cancer.
4

Fatty acid composition of microsomal and soluble fractions of mammary adenocareinomas in mice

Raines, Gloria Mae Kinnett January 1976 (has links)
It has been suggested that membrane characteristics associated with carcinomas could be related to an altered molecular structure of lipids inplasma membrane. The microsomal and soluble fractions of the cell are major sites of de novo synthesis and elongation/desaturation of fatty acids. It was the purpose of this study to compare the fatty acid composition of microsomal and soluble fractions isolated from mammary adenocarcinomas with that of normal mammary tissue and to determine if deviations found in the plasma membrane isolated from tumors could be observed at these subcellular levels.Microsomal and soluble fractions were isolated by differential centrifugation from mammary adenocarcinomas and from normal mammary tissue of Strain A female mice. Activities of nicotinamide adenine dinucleotide, reduced (NADH) dependent cytochrome c reductase andnicotinamide adenine dinucleotide phosphate, reduced (NADPH) dependent cytochrome c reductase in these fractions were determined. The fatty acids were extracted, methylated, and methyl esters identified and quantified using gas liquid chromatography. Polar and non-polar GLC columns, silver nitrate thin layer chromatography, hydrogenation, and spiking was used to confirm the identity of some fatty acids.Fatty acid composition of the microsomal and soluble fractions was similar in tumor and normal tissue. There was a greater percentage of C24:1 in tumors. A reversal of the oleic to stearic acid ratio, an increase in the level of palmitic acid, and a tendency toward long chain polyenoic fatty acids, as reported in studies on the plasma membrane isolated from tumors, was not evident in either the microsomal or soluble fractions. There was evidence of greater utilization of NADPH in the reduction of cytochrome c reductase in tumors. This may result in a decreased availability of NADPH for fatty acid synthetase and lipogenesis.Results of this study do not demonstrate support for a shift in the biosynthetic pathway for the synthesis of fatty acids in carcinomas. It is possible that changes in the lipid composition in the plasma membrane of tumor cells occur after initial incorporation or a shift in biosynthesis could occur in the mitochondria, another site of de novo synthesis and elongation/desaturation of fatty acids.
5

Identification of a novel therapeutic strategy from molecular stratification of oesophageal adenocarcinoma

Ong, Chin-Ann Johnny January 2013 (has links)
No description available.
6

The role of mucus glycoproteins in the oesophagus

Arul, Suren January 2000 (has links)
No description available.
7

CD44 in cervical cancer

Ibrahim, Emad Moussa January 2002 (has links)
No description available.
8

Endoscopic measurement of electric impedance spectra and their dependence on tissue properties in Barret's oesophagus

Gonzalez-Correa, Carlos-Augusto January 2001 (has links)
No description available.
9

An immunohistochemical study of endometrial hyperplasia and neoplasia

Sivridis, E. January 1986 (has links)
No description available.
10

Identification and characterisation of genes over-expressed in gastric adenocarcinomas /

Tsui, Wai-yin. January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 153-164).

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