959 resultados para Single-grade classes


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Polymorphous low-grade adenocarcinoma (PLGA) is a subtype of salivary gland carcinoma with a marked predilection for the minor salivary glands. The diagnosis of this lesion can be a challenge in incisional biopsies because of its similarity to other salivary neoplasms and the difficulty of analyzing its infiltrative nature and neurotropism. Diagnosis can be facilitated, however, by immunohistochemistry, a technique that has become a fundamental tool to the pathologist. The purpose of this study was analyze the immunohistochemical aspects of 4 cases that were examined in the São José dos Campos School of Dentistry. The patients included 4 women, ages 32 to 57 years (mean, 50 years), who reported an intraoral painless lesion, ranging in size from 1 to 3 cm (mean, 1.75 cm) with a variable evolution period. Histologically, the lesions showed similar aspects, characterized by polymorphous growth pattern, including solid, cribriform, trabecular, papillary, and single-file arrays. The tumors showed positivity to cytokeratins (Cks) 7 and 8 and vimentin, variable expression for Ck 14, and a negative reaction to Cks 13 and 19 and muscle-specific actin. PLGA is a tumor of the salivary gland that must be distinguished from other neoplasms for therapeutic and prognostic considerations, and the panel of antibodies employed in this study was effective for its diagnosis.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Ao se aplicar uma tração exterior a uma fibra óptica, seu índice de refração pode modificar devido ao efeito foto-elástico. Quando a fibra contém uma grade de Bragg inscrita em seu núcleo, além do índice de refração seu período espacial também modifica, permitindo sua aplicação como sensores ópticos de temperatura e/ou deformação de alta sensitvidade. Do ponto de vista teórico, até o presente a operação de sensores baseados em fibras ópticas com grade de Brag (FGB) é explicada pelo efeito foto-elástico, através de componentes adequadas do tensor foto-elástico de fibras de sílica dopadas com germânio (germano-silicatadas). Em praticamente toda a literatura previamente estudada, apenas este tipo de fibra óptica tem suas propriedades optomecânicas bem definidas, o que pode representar uma restrição. Nesta dissertação apresentamos uma formulação teórica alternativa para o estudo das propriedades de um sensor de deformação longitudinal baseado em fibra óptica com grade de Bragg (FGB) que não depende do conhecimento prévio das componentes do tensor foto-elástico, e que leva a resultados que dependem apenas da razão de Poisson da fibra, uma característica mecânica facilmente mensurável, e de seu índice de refração efetivo. Os resultados obtidos com este modelo apresentam ótima concordância com aqueles obtidos pelo modelo conhecido da literatura, além de permitir estimar o comportamento de outros parâmetros relacionados ao espectro de refletividade da FGB.

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Os solos são classificados por seus horizontes e atributos diagnósticos para que possam ser agrupados por semelhanças e fornecer informações relativas a sua utilização. Conhecer a variabilidade espacial dos atributos diagnósticos utilizados na classificação do solo é importante na definição do manejo do solo. O objetivo desse trabalho foi verificar a dependência espacial dos atributos diagnósticos na classificação de solos (índice de avermelhamento, gradiente textural e V%) e identificar os limites entre classes de solos. O índice de avermelhamento, gradiente textural e V% do solo foram determinados nos horizontes A e B de uma grade amostral de 65 pontos coletados no Horto da cidade de Mogi-Guaçu, SP. A análise da variabilidade espacial dos atributos estudados foi realizada por meio da geoestatística, considerando a dependência espacial no intervalo de amostragem. Todos os atributos do Horto de Mogi-Guaçu apresentaram dependência espacial e foram interpolados pela krigagem ordinária para obtenção dos mapas temáticos. Com base nos mapas de índice de avermelhamento, gradiente textural e V% foi possível gerar o mapa de classes de solos. Na área de estudo houve maior ocorrência de solos Vermelho Amarelo sem migração de argila do horizonte A para o B e Distrófico.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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We performed in this study an analysis of Curriculum Astronomy contents the public schools of São Paulo from the available educational materials to teachers and students by the state board of education. We analyzed the conditions that teachers carry out the activities suggested to the teaching-learning situations, considering factors such as time available for classes, available material and the general technical condition to perform the activities suggested by the material. Thereafter, we conducted a search with teachers from public of São Paulo, than three cities in the Vale do Paraíba, in order to trace a general framework of the perception of these teachers about the introduction of Astronomy in Physical during the implementation of the new curriculum

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In this action research study of my 5th grade classroom, I investigated the benefits of a modified block schedule and departmentalization. The research consisted of dividing the 5th grade curriculum into three blocks. Each block consisted of two primary subject areas: Mathematics was paired with Social Studies, Reading was paired with Health, and Writing was paired with Science. These groupings were designed to accommodate district time-allotment requirements and the strengths of each teacher within the 5th grade team. Thus, one teacher taught all of the Mathematics and Social Studies, another all of the Reading and Health, and another all of the Writing and Science. Students had classes with each teacher, each school day. I discovered that this departmentalization had many benefits to both students and teachers. As a result of this research, we plan to continue with our new schedule and further develop it to more fully exploit the educational and professional advantages we found to be a part of the project.

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Five percent of the general population has olfactory or gustatory disorders, although most do not complain about it. However, in some cases, these symptoms can be disabling and may affect quality of life. Anosmia was reported as a possible complication following head injury and neurosurgical procedures, particularly after the resection of tumors located in the anterior fossa and the treatment of aneurysms in the anterior circulation. Nonetheless, in all of these situations, olfactory dysfunction could be explained by damage to the peripheral olfactory system. Here, the authors report a case of complete anosmia associated with ageusia following awake resection of a low-grade glioma involving the left temporoinsular region, with no recovery during a follow-up of 3 years. The frontal lobe was not retracted, and the olfactory tract was not visualized during surgery; therefore, postoperative anosmia and ageusia are likely explained by damage to the cortex and central pathways responsible for these senses. The authors suggest that the patient might have had a subclinical right hemianosmia before surgery, which is a common condition. After resection of the central structures critical for smell and taste processing in the left hemisphere, the patient could have finally had bilateral and complete olfactory and gustatory loss. This is the first known report of permanent anosmia and ageusia following glioma surgery. Because these symptoms might have been underestimated, more attention should be devoted to olfaction and taste, especially with regard to possible subclinical preoperative deficit. (http://thejns.org/doi/abs/10.3171/2012.2.JNS111982)

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Rainfall, throughfall and stemflow were monitored on an event basis in an undisturbed open tropical rainforest with a large number of palm trees located in the southwestern Amazon basin of Brazil. Stemflow samples were collected from 24 trees with a diameter at breast height (DBH) > 5 cm, as well as eight young and four full-grown babassu palms (Attalea speciosa Mart.) for 5 weeks during the peak of the wet season. We calculated rainfall, throughfall and stemflow concentrations and fluxes of Na+, K+, Ca2+, Mg2+,, Cl-, SO42-, NO3- and H+ and stemflow volume-weighted mean concentrations and fluxes for three size classes of broadleaf trees and three size classes of palms. The concentrations of most solutes were higher in stemflow than in rainfall and increased with increasing tree and palm size. Concentration enrichments from rainfall to stemflow and throughfall were particularly high (81-fold) for NO3-. Stemflow fluxes of NO3- and H+ exceeded throughfall fluxes but stemflow fluxes of other solutes were less than throughfall fluxes. Stemflow solute fluxes to the forest soil were dominated by fluxes on babassu palms, which represented only 4% of total stem number and 10% of total basal area. For NO3-, stemflow contributed 51% of the total mass of nitrogen delivered to the forest floor (stemflow + throughfall) and represented more than a 2000-fold increase in NO3- flux compared what would have been delivered by rainfall alone on the equivalent area. Because these highly localized fluxes of both water and NO3- persist in time and space, they have the potential to affect patterns of soil moisture, microbial populations and other features of soil biogeochemistry conducive to the creation of hotspots for nitrogen leaching and denitrification, which could amount to an important fraction of total ecosystem fluxes. Because these hotspots occur over very small areas, they have likely gone undetected in previous studies and need to be considered as an important feature of the biogeochemistry of palm-rich tropical forest. (C) 2011 Elsevier B.V. All rights reserved.

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Background. Lung transplantation has become a standard procedure for some end-stage lung diseases, but primary graft dysfunction (PGD) is an inherent problem that impacts early and late outcomes. The aim of this study was to define the incidence, risk factors, and impact of mechanical ventilation time on mortality rates among a retrospective cohort of lung transplantations performed in a single institution. Methods. We performed a retrospective study of 118 lung transplantations performed between January 2003 and July 2010. The most severe form of PGD (grade III) as defined at 48 and 72 hours was examined for risk factors by multivariable logistic regression models using donor, recipient, and transplant variables. Results. The overall incidence of PGD at 48 hours was 19.8%, and 15.4% at 72 hours. According multivariate analysis, risk factors associated with PGD were donor smoking history for 48 hours (adjusted odds ratio [OR], 4.83; 95% confidence interval [CI], 1.236-18.896; P = .022) and older donors for 72 hours (adjusted OR, 1.046; 95% CI, 0.997-1.098; P = .022). The operative mortality was 52.9% among patients with PGD versus 20.3% at 48 hours (P = .012). At 72 hours, the mortality rate was 58.3% versus 21.2% (P = .013). The 90-days mortality was also higher among patients with PGD. The mechanical ventilation time was longer in patients with PGD III at 48 hours namely, a mean time of 72 versus 24 hours (P = .001). When PGD was defined at 72 hours, the mean ventilation time was even longer, namely 151 versus 24 hours (P < .001). The mean overall survival for patients who developed PGD at 48 hours was 490.9 versus 1665.5 days for subjects without PGD (P = .001). Considering PGD only at 72 hours, the mean survival was 177.7 days for the PGD group and 1628.9 days for the other patients (P < .001). Conclusion. PGD showed an important impacts on operative and 90-day mortality rates, mechanical ventilation time, and overall survival among lung transplant patients. PGD at 72 hours was a better predictor of lung transplant outcomes than at 48 hours. The use of donors with a smoking history or of advanced age were risk factors for the development of PGD.

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Abstract Background This study is an analysis of the prevalence of polymorphous low grade adenocarcinoma (PLGA) in epidemiological surveys of salivary tumors published in the English language from 1992 to 2012. Methods These surveys included studies from different researchers, countries and continents. The 57 surveys for which it was possible to calculate the percentage of PLGAs among all malignant minor salivary gland tumors (MMSGT) were included in this review. Results The statistical analyses show significant differences in the PLGA percentage by time period, country and continent in the studies included in this review. The percentage of PLGAs among MMSGTs varied among the studies, ranging from 0.0% to 46.8%. PLGA rates have varied over the period studied and have most recently increased. The frequency of reported PLGA cases also varied from 0.0% to 24.8% by the country in which the MMSGT studies were performed. The PLGA percentages also varied significantly by continent, with frequencies ranging from 3.9% in Asia to 20.0% in Oceania Conclusion Based on these results, we concluded that although the accuracy of PLGA diagnoses has improved, they remain a challenge for pathologists. To facilitate PLGA diagnoses, we have therefore made some suggestions for pathologists regarding tumors composed of single-layer strands of cells that form all of the histological patterns present in the tumor, consistency of the cytological appearance and uniformly positive CK7, vimentin and S100 immunohistochemistry, which indicate a single PLGA phenotype. Virtual slide The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1059098656858324

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In the past decade, the advent of efficient genome sequencing tools and high-throughput experimental biotechnology has lead to enormous progress in the life science. Among the most important innovations is the microarray tecnology. It allows to quantify the expression for thousands of genes simultaneously by measurin the hybridization from a tissue of interest to probes on a small glass or plastic slide. The characteristics of these data include a fair amount of random noise, a predictor dimension in the thousand, and a sample noise in the dozens. One of the most exciting areas to which microarray technology has been applied is the challenge of deciphering complex disease such as cancer. In these studies, samples are taken from two or more groups of individuals with heterogeneous phenotypes, pathologies, or clinical outcomes. these samples are hybridized to microarrays in an effort to find a small number of genes which are strongly correlated with the group of individuals. Eventhough today methods to analyse the data are welle developed and close to reach a standard organization (through the effort of preposed International project like Microarray Gene Expression Data -MGED- Society [1]) it is not unfrequant to stumble in a clinician's question that do not have a compelling statistical method that could permit to answer it.The contribution of this dissertation in deciphering disease regards the development of new approaches aiming at handle open problems posed by clinicians in handle specific experimental designs. In Chapter 1 starting from a biological necessary introduction, we revise the microarray tecnologies and all the important steps that involve an experiment from the production of the array, to the quality controls ending with preprocessing steps that will be used into the data analysis in the rest of the dissertation. While in Chapter 2 a critical review of standard analysis methods are provided stressing most of problems that In Chapter 3 is introduced a method to adress the issue of unbalanced design of miacroarray experiments. In microarray experiments, experimental design is a crucial starting-point for obtaining reasonable results. In a two-class problem, an equal or similar number of samples it should be collected between the two classes. However in some cases, e.g. rare pathologies, the approach to be taken is less evident. We propose to address this issue by applying a modified version of SAM [2]. MultiSAM consists in a reiterated application of a SAM analysis, comparing the less populated class (LPC) with 1,000 random samplings of the same size from the more populated class (MPC) A list of the differentially expressed genes is generated for each SAM application. After 1,000 reiterations, each single probe given a "score" ranging from 0 to 1,000 based on its recurrence in the 1,000 lists as differentially expressed. The performance of MultiSAM was compared to the performance of SAM and LIMMA [3] over two simulated data sets via beta and exponential distribution. The results of all three algorithms over low- noise data sets seems acceptable However, on a real unbalanced two-channel data set reagardin Chronic Lymphocitic Leukemia, LIMMA finds no significant probe, SAM finds 23 significantly changed probes but cannot separate the two classes, while MultiSAM finds 122 probes with score >300 and separates the data into two clusters by hierarchical clustering. We also report extra-assay validation in terms of differentially expressed genes Although standard algorithms perform well over low-noise simulated data sets, multi-SAM seems to be the only one able to reveal subtle differences in gene expression profiles on real unbalanced data. In Chapter 4 a method to adress similarities evaluation in a three-class prblem by means of Relevance Vector Machine [4] is described. In fact, looking at microarray data in a prognostic and diagnostic clinical framework, not only differences could have a crucial role. In some cases similarities can give useful and, sometimes even more, important information. The goal, given three classes, could be to establish, with a certain level of confidence, if the third one is similar to the first or the second one. In this work we show that Relevance Vector Machine (RVM) [2] could be a possible solutions to the limitation of standard supervised classification. In fact, RVM offers many advantages compared, for example, with his well-known precursor (Support Vector Machine - SVM [3]). Among these advantages, the estimate of posterior probability of class membership represents a key feature to address the similarity issue. This is a highly important, but often overlooked, option of any practical pattern recognition system. We focused on Tumor-Grade-three-class problem, so we have 67 samples of grade I (G1), 54 samples of grade 3 (G3) and 100 samples of grade 2 (G2). The goal is to find a model able to separate G1 from G3, then evaluate the third class G2 as test-set to obtain the probability for samples of G2 to be member of class G1 or class G3. The analysis showed that breast cancer samples of grade II have a molecular profile more similar to breast cancer samples of grade I. Looking at the literature this result have been guessed, but no measure of significance was gived before.