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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

Expressão imuno-histoquímica de Bcl-2, Ki-67 e caspase-3 ativa em líquen plano oral e leucoplasia com diferentes graus de displasia / Immunohistochemical expression of Bcl-2, Ki-67 and active caspase-3 in oral lichen planus and leukoplakia with different degrees of dysplasia

Fernanda Mombrini Pigatti 26 August 2011 (has links)
O líquen plano oral (LPO) é uma doença inflamatória crônica de causa desconhecida, e seu potencial de malignização é um tema bastante controverso. Diversos estudos têm sugerido que pacientes portadores de líquen plano apresentam um maior risco de desenvolver câncer. Contudo, muitos autores acreditam que não haja dados suficientes que provem uma associação entre líquen plano e câncer. Para esses autores, a maioria dos casos que sofreram transformação maligna é decorrente de falhas no diagnóstico inicial da lesão. Portanto, objetivou-se avaliar a expressão imuno-histoquímica das proteínas relacionadas à apoptose e proliferação celular, respectivamente caspase-3 ativa, Bcl-2 e Ki-67 no LPO e em displasias epiteliais na tentativa de explicar a polêmica em relação ao potencial de transformação maligna do LPO e enfatizar a importância de um acompanhamento de longo prazo dos pacientes com esta doença. Com esse propósito, foram selecionadas 14 amostras de LPO, 14 amostras de leucoplasia com displasia epitelial, além de 09 amostras de mucosa bucal normal como controle. A avaliação da expressão de caspase-3 ativa, Bcl-2 e Ki-67 foi conduzida de acordo com a técnica da imunoperoxidase. A contagem das células imunomarcadas nas amostras de LPO, de leucoplasia com displasia epitelial e de mucosa bucal normal resultou em número destas células por mm2 nas diferentes regiões (camada basal, camada suprabasal e infiltrado inflamatório) para cada imunomarcador. A expressão de Bcl-2 em células epiteliais, da camada basal, ocorreu mais frequentemente no grupo da leucoplasia com displasia epitelial, com diferença estatística entre o grupo do LPO e o grupo controle. Verificou-se também, uma alta expressão da proteína Bcl-2 em células inflamatórias de lesões de LPO e de leucoplasia com displasia epitelial. A expressão do marcador Ki-67 foi superior em todos os níveis teciduais analisados nas lesões de LPO e de leucoplasia com displasia epitelial quando comparados com o grupo controle. Concluiu-se que a expressão mais elevada das proteínas Bcl-2 e Ki-67 nos casos de LPO e de leucoplasia com displasia epitelial, podem revelar a possibilidade da presença de alterações moleculares morfologicamente imperceptíveis. / The oral lichen planus (OLP) is a chronic inflammatory disease of unknown cause, and its malignant potential is a very controversial issue. Several studies have suggested that patients with lichen planus have a higher risk of developing cancer. However, many authors believe that there is insufficient evidence to prove an association between lichen planus and cancer. For these authors, most of the cases that had undergone malignant transformation is due to flaws in the lesion initial diagnosis. Therefore, the aim was to evaluate the immunohistochemical expression of proteins related to apoptosis and cell proliferation, respectively active caspase-3, Bcl-2 and Ki-67 in epithelial dysplasia and LPO in an attempt to explain the controversy regarding the potential malignant transformation of OLP and emphasize the importance of a long-term monitoring of patients with this disease. For this purpose, we selected 14 samples of OLP, 14 samples of leukoplakia with epithelial dysplasia, and 09 samples of normal oral mucosa as controls. The evaluation of the expression of active caspase-3, Bcl-2 and Ki-67 was conducted in accordance with the immunoperoxidase technique. The immunostained cells counting in samples of OLP, epithelial dysplasia in leukoplakia and normal oral mucosa resulted in a number of these cells per mm2 in the different regions (basal layer, suprabasal layer and inflammatory infiltrate) for each immunostained. The expression of Bcl-2 in epithelial cells, the basal layer, occurred more frequently in the group of leukoplakia with epithelial dysplasia, with statistical difference between the group of OLP and the control group. There was a high expression of Bcl-2 protein in inflammatory cells in OLP lesions and leukoplakia with epithelial dysplasia. The expression of the marker Ki-67 was superior in all analyzed tissue levels in OLP lesions and leukoplakia with epithelial dysplasia when compared to the control group. It was concluded that the highest expression of Bcl-2 protein and Ki-67 in cases of OLP and leukoplakia with epithelial dysplasia, can reveal the possible presence of molecular changes morphologically imperceptible.
32

Avaliação da poluição atmosférica de elementos químicos pela análise de líquen epifítico no campus da Cidade Universitária de São Paulo / Assessment of atmospheric pollution of chemical elements by epiphytic lichen analysis at the campus of the São Paulo University

Rosiana Rocho Rocha 05 November 2015 (has links)
A poluição atmosférica tem sido tema frequente de pesquisas, devido aos efeitos que podem afetar a saúde dos seres vivos, o meio ambiente e clima. A fim de identificar as fontes de emissão dos poluentes e de seus efeitos, o método de biomonitoramento vem sendo estudado devido ao seu baixo custo e a possibilidade de amostragem em amplas áreas geográficas. Neste trabalho, para biomonitoramento passivo da poluição atmosférica no campus da Cidade Universitária Armando Salles de Oliveira (CUASO) da Universidade de São Paulo, foi utilizado líquen epifítico da espécie Canoparmelia texana. Os liquens coletados em troncos de árvores de diferentes pontos da CUASO foram limpos, secos por liofilização e moídos para análise pelos métodos de espectrometria de fluorescência de raios X (XRFS) e análise por ativação neutrônica (NAA). Na XRFS as amostras preparadas na forma de pastilhas foram analisadas para determinação de As, Br, Ca, Cl, Cr, Cu, Fe, K, Mn, Rb, S, Sr e Zn. Na NAA, alíquotas de amostras de liquens juntamente com padrões sintéticos de elementos foram irradiados no reator IEA-R1 e as atividades induzidas medidas em espectrômetro de raios gama para determinação de As, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, Fe, K, La, Mg, Mn, Rb, Sb, Sc, Se, U, V e Zn. A qualidade dos resultados analíticos foi avaliada pela análise de materiais de referência certificados. Seus resultados de desvios padrão relativos e de erros relativos foram inferiores a 15 % para a maioria dos elementos. Os valores de diferença padronizada ou En score obtidos foram inferiores a |1| indicando resultados satisfatórios. A homogeneidade da amostra de líquen foi avaliada tanto pela NAA como pela XRFS por meio das análises em replicatas e estes resultados indicaram a boa reprodutibilidade dos resultados em relação aos elementos determinados. Os resultados dos liquens da CUASO mostraram que as concentrações médias de As, Br, Ca, Cd, Co, Cr, Cs, Rb, Sb, Se e U foram mais altas do que daquelas das regiões consideradas não poluídas e para Fe, K, La, S, V e Zn foram da mesma ordem de grandeza. O estudo da correlação entre os elementos apresentou alta correlação (r > 0,7) para elementos originários de fontes naturais e antrópicas. A análise de componentes principais (PCA) aplicada aos resultados teve seis componentes principais, onde os componentes 1 e 2 corresponderam a 52,9 % da variância dos dados. Os resultados dos fatores de enriquecimento (FE) calculados entre os liquens da CUASO e de uma região considerada limpa foram maiores que 1 para maioria dos elementos, indicando que estes elementos podem ser de fontes antrópicas. Pelos resultados obtidos concluise que a origem dos elementos determinados nos liquens da CUASO pode ser atribuída a fontes como a resuspensão de partículas de solo e emissões antrópicas. / Air pollution has been a frequent topic of research, due to the effects that it can cause on the health of living organisms, environment and climate. In order to identify pollution sources and their effects, biomonitoring has been studied due to its low cost and possibility of sampling in wide geographic areas. In this study for passive biomonitoring of air pollution levels at the Cidade Universitária Armando Salles de Oliveira (CUASO), University of São Paulo campus, epiphytic lichens of Canoparmelia texana species were used. The lichens collected from tree barks at different sampling sites in the CUASO were cleaned, freeze-dried and ground for analyses. Lichen samples were analyzed by X - ray fluorescence spectrometry (XRFS) and neutron activation analysis (NAA). For XRFS, cylindrical pellets of samples were prepared to determine As, Br, Ca, Cl, Cr, Cu, Fe, K, Mn, Rb, S, Sr and Zn. For NAA, lichen sample aliquots along with synthetic elemental standards were irradiated both for short and long periods at the IEA-R1 nuclear research reactor. The induced activities were measured by a gamma ray spectrometer to determine As, Br, Ca Cd, Cl, Co, Cr, Cs, Cu, Fe, K, La, Mg, Mn, Rb, Sb, Sc, Se, U, V and Zn. The precision and accuracy of the results were evaluated by the analysis of certified reference materials (MRCs). Their results of relative errors and standard deviations were below 15% for most of the elements. The standardized difference or En score values were lower than |1| indicating satisfactory results. Replicate analyses of a lichen sample by XRFS and NAA, indicated good homogeneity of the sample for the elements determined. The lichen results showed that the mean concentrations of As, Br, Ca, Cd, Co, Cr, Cs, Rb, Sb, Se and U were higher in samples from CUASO than those from regions considered unpolluted. For Fe, K, La, S, V and Zn, they were of the same order of magnitude. The correlation study between the elements showed high correlation (r > 0.7) for elements originated from the natural and anthropogenic sources. The principal component analysis (PCA) applied to the results showed six major components, where components 1 and 2 accounted for 52.9 % of the variance of the data. Enrichment factors (EF) calculated for the results of lichens from CUASO and a region considered unpolluted were EF> 1 for most elements, showing that these elements may be from anthropogenic sources. From the results obtained in this study can be concluded that the elements found in lichens from CUASO can be originated from sources such as resuspension of soil particles and anthropogenic emissions.
33

Biogeography and Natural History of Tiger Moths and Spongillaflies of Intermountain North America with Experimental Studies of Host Preference in the Lichen-Feeder Cisthene angelus (Insecta: Lepdioptera: Erebidae: Arctiinae and Neuroptera: Sisyridae)

Fisher, Makani Layne 01 December 2018 (has links)
The Intermountain West is comprised of impressive land formations, numerous ecoregions, and a unique biota. The area has many flora and fauna that have been investigated, but the region is generally considered undersampled when it comes to insects. However, I propose the matter to be a lack of shared experience in identifying key insect species and the underutilization of professional and personal collections. These impediments are highlighted by two insect groups in the Intermountain West: spongillaflies and tiger moths.Spongillaflies can be difficult to recognize for the general entomologist and have rarely been recorded in the Intermountain West. My colleagues and I recently discovered a large population of spongillaflies in Utah that we present as a substantial additional record. I also followed the population throughout the 2016 field season to make natural history observations. I identified the spongillaflies to be Climacia californica and their associated host to be Ephydatia fluviatilis. During the season, a total of 1,731 specimens were collected, light traps were the most effective sampling technique and the population had one mass emergence event. I hope my work and figures will help investigators as they continue to search the area for spongillaflies. Tiger moths on the other hand have largely been collected in the Intermountain West and are easily recognized, generally being brightly colored. Because of these bright colors, they attract collectors and have been sampled heavily throughout the Intermountain West. However, until now, these records have not been utilized and tucked away in collections. We took the vast amount of records and used them to create predicted models of biogeography for each tiger moth species in the area. We successfully created species level ecological niche models (ENM) analyzing environmental variables such as temperature, precipitation, elevation, and vegetation. Overall, I found tiger moths can be collected almost everywhere and during each month of the year with 93 different species scattered across the region. I anticipate our ENM models to help researchers locate tiger moths of interest to investigate within the Intermountain West.During my studies, I investigated in detail the lichen feeding tiger moths (Lithosiini). Many tiger moths eat toxic plants, but only a few in the area consume lichen, an unusual host because of their secondary defensive chemicals. I investigated how these chemicals impacted Cisthene angelus caterpillars host selection by simultaneously offering them various lichens with differing chemistries. I expected these caterpillars to avoid usnic acid as it deterred other lichen feeding tiger moths. However, these caterpillars surprised me by consistently consuming the acid and being largely polyphagous. Our future work will be directed at how caterpillars balance nutritional needs and the chemicals they sequester.
34

Analyse der Expression von MAGE-A-Antigenen in Präkursorläsionen und manifesten Tumoren des oralen Plattenepithelkarzinoms / Analysis of the expression of MAGE-A-antigens in oral precancerous lesions and neoplasm of the oral squamous cell carcinoma

Krauss, Eva January 2011 (has links) (PDF)
Orale Plattenepithelkarzinome entwickeln sich häufig aus Präkanzerosen. Trotz der Frühdiagnostik ist es für den Kliniker und den Pathologen meist schwierig eine Präkanzerose, die zur Entartung neigt, rechtzeitig als solche zu erkennen. MAGE-A-Antigene sind Tumorantigene, die nur in malignen Zellen vorkommen. Diese Antigene können dazu dienen, Karzinome früher als solche zu erkennen. Das Ziel dieser Studie war, diese Hypothese zu bestätigen, indem gutartige, präkanzeröse und karzinomatöse Veränderung untersucht wurden. Dazu wurden retrospektiv Biopsien der oralen Schleimhaut (orale Ulzera, Epulitiden, follikuläre Zysten, Lichen planus, Leukolakien, epitheliale Dysplasien und Carcinomata in situ) untersucht. Diese wurden immunhistochemisch mit dem polyklonalen Antikörper MAGE-A 57B angefärbt. Dabei stellte sich heraus, dass MAGE-A-Antigene nicht in gutartigen Veränderungen vorkommen, jedoch zu 33-65% in präkanzerösen und malignen Läsionen. Ein weiteres Ziel umfasste die Untersuchung der kritischen Randbereiche. Hier wurde bei den positv gefärbten Präparaten eine eindeutige Grenze zwischen benigner und maligner Schleimhaut durch die Anfärbung mit mAb-57B sichtbar. / Oral squamous cell carcinoma develops often out of predamaged oral mucosa. Despite of early diagnostic it is difficult for the physician and pathologist to distinguish between precancerous and cancerous lesions. MAGE-A antigens are tumor antigens that are found solely in malignant transformed cells. So these antigens might be useful in detecting cancerous lesions. The aim of this study was to verify this hypothesis by comparing MAGE-A expression in benign, precancerous, and cancerous lesions of the oral mucosa. Therefore we retrospectively examined biopsies of different oral lesions (oral ulcers, dental follicles, epulises, oral lichen planus, leukoplakia, epithelial dysplasias and carcinomas in situ). The lesions were immunohistochemically stained with the poly-MAGE-A antibody 57B. MAGE-A antigens were nearly not detectable via immunohistochemistry in benign lesions of the oral mucosa. The staining rate of precancerous lesions or malignant lesions alternated from 33% to 65%. The second aim concerned the margins of the lesions. In positive stained lesions the antibody could make it easier to detect the margin between benign and malignant lesions.
35

Patienters upplevelse av oral hälsa vid diagnosen erosiv oral lichen planus : En kvalitativ studie

Altersved, Karin, Wallén, Agneta January 2013 (has links)
No description available.
36

Effekter av luftföroreningar på lavar och grönalger på lind i Norrköpings kommun

Sonelin, Sarah January 2012 (has links)
Syftet med denna studie var att undersöka vilka effekter luftföroreringar har på lavar och grönalger som växer på lindar, genom att jämföra lavfloran i urban miljö och i landsbygdsmiljö. Mer specifikt var syftet att utreda hur avstånd till närmaste väg, trafikintensitet och trädets exponerade respektive icke-exponerade sida gentemot en väg påverkar lavfloran i urban miljö. 18 utvalda lavarter samt grönalger eftersöktes på 86 lindar i urban miljö och 37 i landsbygdsmiljö inom Norrköpings kommun. Resultaten visade att artantalet, samt förekomsten och täckningsgraden för flertalet lavar var större i landsbygdsmiljö jämfört med urban miljö. Kortare avstånd till närmaste väg och hög trafikintensitet hade negativ effekt på flertalet lavar. I båda fallen visades det motsatta för grönalger. Det fanns ingen skillnad i förekomster av lavar om de exponerades utåt mot vägen eller bort från vägen. / The aim of this study was to investigate which effects air pollution has on epiphytic lichens and green algae in urban and rural environment, respectively.  More specifically, the aim was to investigate the effects on the lichen flora of distance to the nearest road, traffic volume and to compare the effect of tree sides exposed and not exposed to roads in the urban environment. 18 selected lichen selected species and green algae as a taxonomic group where searched on 86 lime trees in urban and 37 in rural environments in the Norrköping municipality. The species number was higher and the majority of the lichens occurred more often and showed a higher cover on trees in rural areas compared to trees in the urban environment. Shorter distance to the nearest road and high traffic volume had a negative impact on the majority of lichens. In both cases the opposite was shown for the green algal group. The lichens occurred equally often on the sides of the trees that were exposed to the road as on the sides that were not exposed to the road.
37

Lichen decline in areas with increased nitrogen deposition might be explained by parasitic fungi : A survey of parasitic fungi on the lichen Alectoria sarmentosa after 4 years of nitrogen fertilisation

Ström, Caspar January 2011 (has links)
Nitrogen (N) deposition in Europe has recently increased and is expected to continue to increase in the future. There is a well-documented decline in lichen diversity with higher N availability, although the mechanisms behind this are poorly known. In this study, I tested whether attacks by fungal parasites increase with higher N deposition. This pattern has been found in a number of studies on vascular plants, but it has never been investigated for lichens. I surveyed dark lesions and discolourings caused by fungi on the pollution-sensitive lichen Alectoria sarmentosa, after 4 years of increased N deposition in a whole tree fertilisation experiment in a boreal spruce forest. I found two species of fungi growing on the investigated lichen thalli. One of these species responded positively to increased N deposition. The results show that lichens can suffer from increased parasite attacks under a higher N load. Further studies using multiple lichen species and many years of recording are needed to understand the importance of parasites for the response of whole lichen communities to an increased N load.
38

Calving ground habitat selection of boreal woodland caribou (Rangifer tarandus caribou) in the Owl-Flintstone range

Dupont, Daniel L. J. 11 April 2014 (has links)
The Owl-Flintstone range in southeastern Manitoba is among the most at risk in the province. Through a series of transects and plots established throughout the study area, this study characterized calving habitat at a fine scale, examined the use of caribou calving areas by large mammals and examined if a calving habitat model correctly identified high quality calving habitat. Parturient females utilized black spruce dominated islands and peninsulas on lakes as well as islands and peninsulas in bogs. Bear utilized both predicted low and high quality sites. Black spruce and lichen cover were significantly greater within known calving sites compared to predicted low quality habitat. Forbs, herbs and downed woody debris values were significantly lower within known calving sites compared to predicted high quality sites. The calving habitat model correctly identified both high quality and low quality calving habitat in the Owl-Flintstone range, however parameters could be refined.
39

Squamous Cell Carcinoma of the Vulva and Adjacent Lesions Treated at Nagoya University Hospital from 1965 to 1997

Nagasaka, Tetsuro, Nakashima, Nobuo, Harada, Tomoko, Okamoto, Tomomitsu, Mizutani, Shigehiko, Ishiko, Hiroaki 11 1900 (has links)
No description available.
40

Estudo do potencial de transformação maligna do líquen plano bucal: análise histológica, histoquímica e imunoistoquímica

Sousa, Fernando Augusto Cervantes Garcia de [UNESP] 25 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-25Bitstream added on 2014-06-13T19:23:17Z : No. of bitstreams: 1 sousa_fscg_dr_sjc.pdf: 590497 bytes, checksum: 402da6099907d4db4a4b39c13731e3c6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho foi analisar possíveis alterações dos mecanismos de proliferação celular e apoptose no líquen plano bucal, comparando-as com as observadas na displasia epitelial e no carcinoma epidermóide, visando avaliar o seu potencial de transformação maligna. Foram selecionados 24 casos de cada lesão e a partir deles, novos cortes histológicos foram obtidos, sendo parte submetidos à técnica de AgNOR e parte à técnica imunoistoquímica da estreptoavidina-biotina-peroxidase para análise da expressão das proteínas PCNA, p53, bax e bcl-2. A média de NORs/núcleo no líquen plano bucal, na displasia epitelial e no carcinoma epidermóide bucal foram, respectivamente, 1,74±0,32, 2,42±0,62 e 2,41±0,61. A análise de variância revelou haver diferença estatisticamente significante entre o líquen plano bucal e as demais lesões (p<0,05). Quanto à PCNA, p53, bax e bcl-2, o teste de qui-quadrado não revelou haver diferença significante entre a expressão da p53 e da bcl-2. Contudo, a expressão da PCNA foi significativamente menor no líquen plano bucal do que nas demais lesões. Não houve diferença estaticamente significante entre a expressão da PCNA e da bax na displasia epitelial e no carcinoma epidermóide bucal. Conclui-se que alterações na expressão destas proteínas podem ser observadas tanto no líquen plano bucal quanto na displasia epitelial e no carcinoma epidermóide bucal, sugerindo o potencial de transformação maligna desta lesão e enfatizando a importância do acompanhamento em longo prazo dos pacientes. Neste contexto, a análise das NORs se mostrou ferramenta útil em avaliar os casos de líquen plano bucal que apresentem maior risco de transformação maligna. / The purpose of this study was to analyze possible alterations in the mechanisms of cell proliferation and apoptosis in oral lichen planus, comparing them with those observed in epithelial dysplasia and squamous cell carcinoma, aiming to establish its malignant transformation potential. Twenty-four cases of each lesion were selected and new histological cuts were obtained, being part of the cuts submitted to the AgNOR and part to the immunohistochemical technique of streptoavidine-biotin technique for analysis of the expression of the PCNA, bax and bcl-2 proteins. The NORs/nucleous mean for oral lichen planus, epithelial dysplasia and squamous cell carcinoma was respectively 1.74±0.32, 2.42±0.62 and 2.41±0.61. Analysis of variance showed statistically significant difference between the oral lichen planus and the others lesions (p<0.05). Regarding PCNA, p53, bax and bcl-2, chi-squared test showed no significant differences between the expression of p53 and bcl-2. However, the expression of PCNA was significantly lower in oral lichen planus than in epithelial dysplasia and oral squamous cell carcinoma. No significant differences between the expression of PCNA and bax in epithelial dysplasia and oral squamous cell carcinoma were observed. It was concluded that alterations in the expression of these proteins can be observed in oral lichen planus, suggesting the potential of malignant transformation of this lesion and emphasizing the importance of follow-up of patients. Within this context, the NORs analysis is a useful tool to evaluate the oral lichen planus cases with high risk of malignant transformation.

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