966 resultados para Lesões pré-malignas orais


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The time perception is critical for environmental adaptation in humans and other species. The temporal processing, has evolved through different neural systems, each responsible for processing different time scales. Among the most studied scales is that spans the arrangement of seconds to minutes. Evidence suggests that the dorsolateral prefrontal (DLPFC) cortex has relationship with the time perception scale of seconds. However, it is unclear whether the deficit of time perception in patients with brain injuries or even "reversible lesions" caused by transcranial magnetic stimulation (TMS) in this region, whether by disruption of other cognitive processes (such as attention and working memory) or the time perception itself. Studies also link the region of DLPFC in emotional regulation and specifically the judgment and emotional anticipation. Given this, our objective was to study the role of the dorsolateral prefrontal cortex in the time perception intervals of active and emotionally neutral stimuli, from the effects of cortical modulation by transcranial direct current stimulation (tDCS), through the cortical excitation (anodic current), inhibition (cathode current) and control (sham) using the ranges of 4 and 8 seconds. Our results showed that there is an underestimation when the picture was presented by 8 seconds, with the anodic current in the right DLPFC, there is an underestimation and with cathodic current in the left DLPFC, there is an overestimation of the time reproduction with neutral ones. The cathodic current over the left DLPFC leads to an inverse effect of neutral ones, an underestimation of time with negative pictures. Positive or negative pictures improved estimates for 8 second and positive pictures inhibited the effect of tDCS in DLPFC in estimating time to 4 seconds. With this work, we conclude that the DLPFC plays a key role in the o time perception and largely corresponds to the stages of memory and decision on the internal clock model. The left hemisphere participates in the perception of time in both active and emotionally neutral contexts, and we can conclude that the ETCC and an effective method to study the cortical functions in the time perception in terms of cause and effect.

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Salivary gland neoplasms exhibit a wide variety of biological behavior and a high morphological diversity raises the interest in researching these lesions. The stem cells are the main source for the generation and maintenance of cell diversity, disorders in the regulation of these cells can lead to the production of altered stem cells, termed cancer stem cells capable of generate the tumor. Researches on cancer stem cells and associated proteins have been developed in some oral cancers; however, their role in salivary gland neoplasms is not well established. Thus, the aim of this study was to identify the tumor parenchyma cells exhibiting stem cell characteristics, by evaluating the immunoreactivity of OCT4 and CD44, in a number of cases of salivary gland neoplasms. The sample consisted of 20 pleomorphic adenomas, 20 mucoepidermoid carcinomas and 20 adenoid cystic carcinoma located in minor and major salivary glands. The expression of OCT4 and CD44 was evaluated by the percentage of positive cells (PP) and the intensity of expression (IE), it is realized the sum of the scores, resulting in the total score immunostaining (PIT) ranging 0-7. All studied cases showed positive expression of OCT4 and CD44 and higher values than the control groups. It was observed that for OCT4 luminal cells and non-luminal were immunostained in the case of pleomorphic adenomas and adenoid cystic carcinoma. Already the immunoreactivity of CD44 was particularly evident in the non-luminal cells of these lesions. In mucoepidermoid carcinomas for both markers, there was immunoreactivity in squamous and intermediate cells and absence of staining mucous cells. For both markers, a statistically significant higher immunostaining was verified in neoplasms located in the major salivary glands compared with lesions in the minor salivary (p<0.001). At the total sample and in the group of minor salivary glands, malignant neoplasms exhibited higher immunoreactivity for OCT4 than pleomorphic adenoma. However, there was no statistically significant difference between the lesions and between their classifications histomorphologic. Analyzing the correlation between OCT4 and CD44 immunoexpressions, a statistically significant moderate positive correlation (r = 0.444) was observed. The high expression of OCT4 and CD44 may indicate that these proteins play an important role in identifying cancer stem cells, allowing a prediction of biological behavior of salivary gland neoplasms.

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Relatório de estágio para a obtenção do grau de mestre em Educação pré-escolar e 1º Ciclo do ensino básico

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Relatório de estágio para a obtenção do grau de mestre em Educação pré-escolar e 1º Ciclo do ensino básico

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Este projeto tem como objetivo identificar e realizar um levantamento dos hábitos de higiene oral das crianças do ensino pré-escolar, bem como, promover, motivar e sensibilizar as crianças acerca desta, ao verificar se a instrução de higiene oral, nomeadamente a escovagem, tem efeito positivo na redução da placa bacteriana medida através do índice de Greene & Vermillion Simplificado (IGV) e, cnsequentemente a aquisição de novos conhecimentos de higiene oral.Após realização de uma consulta de livros relacionados com o tema e pesquisa bibliográfica de artigos científicos, foram selecionados 23 artigos, tendo um limite temporal compreendido entre 2001 e 2013, designadamente 12 anos. Os artigos evidenciam que a maioria dos estudos são referentes aos hábitos de higiene oral e a necessidade da literacia desta em conhecimentos de prevenção das doenças orais. (...)

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O uso para fins ou meios festivos de lazer da droga ilícita MDMA, também chamado de Ecstasy ou Moly, tem vindo a aumentar drasticamente em Portugal e no Mundo. Esta situação desafia os profissionais de saúde para vários parâmetros na saúde oral e geral. O objetivo desta dissertação visa avaliar e descrever as lesões e patologias na cavidade oral que estão relacionadas com o consumo da substância ilícita MDMA. As consequências para a cavidade oral podem ser a xerostomia, o bruxismo, as cáries rampantes, a doença periodontal, o desgaste e a erosão dentária, e as lesões dos tecidos moles. Os indivíduos consumidores podem apresentar carências nutricionais e um estímulo aumentado à dor. A gestão do prognóstico e o tratamento realizado aos consumidores de MDMA, pois afeta vários órgãos e sistemas no corpo humano, requer uma abordagem multidisciplinar que inclui educação, prevenção e tratamento integrados. Esta revisão bibliográfica teve com base artigos publicados em revistas científicos e monografias disponíveis em vários motores de busca. As palavras-chave usadas foram: “ecstasy”, “MDMA”, “oral manifestations”, “oral health”, “substance abuse”, ”overdose treatment”, “xerostomia” e “methamenfetamine” e a sua conjugação. As situações orais, perante as mais prevalentes comorbidades patogénicas relacionadas com o MDMA e outras dependências ilícitas, necessitam de mais atenção e reforço em relação à prática clínica e aos serviços de saúde. Uma das dificuldades para o tratamento correto destes indivíduos é a falta de informação sobre o assunto referente à prática na clínica dentária. A omissão sobre o consumo por parte do paciente bem como de uma recaída no uso, apresentam dúvidas sobre o fator em causa ou até mesmo no diagnóstico. São, muitas vezes, os Médicos Dentistas os primeiros a terem a oportunidade de diagnosticar o aparecimento de possíveis alterações surgidas em virtude do consumo de MDMA.

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The study of beliefs and attitudes has been increasingly valued in the field of modern Sociolinguistics, as, by means of such data, it is possible to clarify phenomena that cannot be explained only by the linguistic context. In relation to that, another factor is extremely important for the analysis of facts connected with language: the appraising attitudes that each speaker attributes to his/her speech and to the other varieties present in the area. This is the reason why the object of study in this work is the beliefs and attitudes of the speakers from the town of Pranchita-PR. Therefore, this work aims at (i) verifying its inhabitants’ opinions concerning the varieties present in the area; (ii) describing and analyzing the speakers’ feelings and opinions in relation to the language of the neighboring country, Argentina. With approximately six thousand inhabitants, Pranchita is ethnically constituted by descendants from several nationalities: Italians, Germans, Polish, Spanish, besides the fact it is on the border with Argentina.  The corpus of this work consists of oral records collected within the scope of the interinstitutional Project Linguistic Beliefs and Attitudes: a study of the relationship between Portuguese and other contact languages, whose informants were divided according to sex, age and school level. Overall, 17 interviews were analyzed by using, as theoretical basis, the works by Labov (1972), López Morales (1993), Moreno Fernández (1998) among others.

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Systemic acquired resistance (SAR) is a broad-spectrum resistance in plants that involves the upregulation of a battery of pathogenesis-related (PR) genes. NPR1 is a key regulator in the signal transduction pathway that leads to SAR. Mutations in NPR1 result in a failure to induce PR genes in systemic tissues and a heightened susceptibility to pathogen infection, whereas overexpression of the NPR1 protein leads to increased induction of the PR genes and enhanced disease resistance. We analyzed the subcellular localization of NPR1 to gain insight into the mechanism by which this protein regulates SAR. An NPR1–green fluorescent protein fusion protein, which functions the same as the endogenous NPR1 protein, was shown to accumulate in the nucleus in response to activators of SAR. To control the nuclear transport of NPR1, we made a fusion of NPR1 with the glucocorticoid receptor hormone binding domain. Using this steroid-inducible system, we clearly demonstrate that nuclear localization of NPR1 is essential for its activity in inducing PR genes.

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Unsteady natural convection inside a triangular cavity subject to a non-instantaneous heating on the inclined walls in the form of an imposed temperature which increases linearly up to a prescribed steady value over a prescribed time is reported. The development of the flow from start-up to a steady-state has been described based on scaling analyses and direct numerical simulations. The ramp temperature has been chosen in such a way that the boundary layer is reached a quasi-steady mode before the growth of the temperature is completed. In this mode the thermal boundary layer at first grows in thickness, then contracts with increasing time. However, if the imposed wall temperature growth period is sufficiently short, the boundary layer develops differently. It is seen that the shape of many houses are isosceles triangular cross-section. The heat transfer process through the roof of the attic-shaped space should be well understood. Because, in the building energy, one of the most important objectives for design and construction of houses is to provide thermal comfort for occupants. Moreover, in the present energy-conscious society it is also a requirement for houses to be energy efficient, i.e. the energy consumption for heating or air-conditioning houses must be minimized.

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The unsteady natural convection boundary layer adjacent to an instantaneously heated inclined plate is investigated using an improved scaling analysis and direct numerical simulations. The development of the unsteady natural convection boundary layer following instantaneous heating may be classified into three distinct stages including a start-up stage, a transitional stage and a steady state stage, which can be clearly identified in the analytical and numerical results. Major scaling relations of the velocity and thicknesses and the flow development time of the natural convection boundary layer are obtained using triple-layer integral solutions and verified by direct numerical simulations over a wide range of flow parameters.

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It is found in the literature that the existing scaling results for the boundary layer thickness, velocity and steady state time for the natural convection flow over an evenly heated plate provide a very poor prediction of the Prandtl number dependency of the flow. However, those scalings provide a good prediction of two other governing parameters’ dependency, the Rayleigh number and the aspect ratio. Therefore, an improved scaling analysis using a triple-layer integral approach and direct numerical simulations have been performed for the natural convection boundary layer along a semi-infinite flat plate with uniform surface heat flux. This heat flux is a ramp function of time, where the temperature gradient on the surface increases with time up to some specific time and then remains constant. The growth of the boundary layer strongly depends on the ramp time. If the ramp time is sufficiently long, the boundary layer reaches a quasi steady mode before the growth of the temperature gradient is completed. In this mode, the thermal boundary layer at first grows in thickness and then contracts with increasing time. However, if the ramp time is sufficiently short, the boundary layer develops differently, but after the wall temperature gradient growth is completed, the boundary layer develops as though the startup had been instantaneous.

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We have examined the magnetotransport properties and the structure, by Rietveld refinement of powder X-ray data, of the phases RE(1.2)Sr(1.8)Mn(2)O(7) (RE = La, Pr, Nd). We find that on cooling, La1.2Sr1.8Mn2O7 undergoes a transition to a nearly perfect ferromagnet with 90% magnetization at 1.45 T, as reported by earlier workers, but the Pr and Nd phases show only a small magnetization that grows gradually as the temperature is decreased. There seems to be significant correlation between electrical transport and the Jahn-Teller elongation of the apical Mn-O bonds in these systems. The elongation of the apical Mn-O bonds forces the nine-coordinate rock-salt site to be occupied preferentially by the smaller rare-earth-metal cations. This preferential occupation is reliably obtained from the X-ray refinement. All three title phases show a magnetoresistance ratio of about 4(corresponding to a magnetoresistance, [R(0)-R(H)]/R(0), of about 75%) at a field of 7 T and temperatures around 100 K.

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In this paper we present the resistivity data for Pr and Zn codoped compound Y1-xPrxBa2[Cu1-yZny](3)O7-delta with 0 < y < 0.1 and x = 0.0, 0.1 and 0.2. The data is analysed in terms of the superconducting critical temperature T-c, residual resistivity rho(0) and the resistivity slope d rho/dT corresponding to the linear rho-T region. It is found that for x = 0.1 Pr has a minimal influence on the in-plane processes for Zn impurity alone affecting slightly T-c and rho(0). The slope dp/dT becomes larger for 0.03 < y < 0.06 leading to larger depining effect and hence slower fall of T, as a function of y. For x = 0.2 there is a drastic change, rho(0) becomes abnormally large, d rho/dT becomes negative implying absence of depinning and a totally pinned charge stripes. Superconductivity vanishes at y = 0.03. It is concluded that for x = 0.2 Pr converts the system from overdoped to underdoped region leading to the universal superconductor-insulator transition.

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Sr1−xPrxTiO3 has recently been shown to exhibit ferroelectricity at room temperature. In this paper powder x-ray and neutron-diffraction patterns of this system at room temperature have been analyzed to show that the system exhibits cubic (Pm-3m) structure for x<=0.05 and tetragonal (I4/mcm) for x>0.05. The redundancy of the noncentrosymmetric structural model (I4cm) in the ferroelectric state suggests the absence of long-range ordered ferroelectric domains and supports the relaxor ferroelectric model for this system.

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M.A. Thesis for the University of Goettingen (1987).