1000 resultados para Vantagem comparativa
Resumo:
The presence of fixed orthodontics appliances interfere on sanitation, allowing periodontal diseases to appear, despite the fact patients keep on visiting the dentist every month. This research aims to determine a protocol for the mechanical control of the dental biofilm performed by the professional. A protocol that was able to maintain the periodontal health of the patients under orthodontic treatment with fixed appliances, and in order to do so, it used a non-controlled, randomized and blind clinical essay. The sample involved 40 adolescents who were under the installation of fixed orthodontics appliances and it was divided in three groups, as follows: monthly controlled group (group 1) composed of 11 patients, the quarterly controlled group (group 2) with 16 patients and the semestrial controlled group (group 3) with 13 patients. For data collection, an interview and clinical exams with probing depth measurement, quantity of keratinized mucosa, Gingival Index and the Plaque Index were used. On the initial exam all patients received brushing guidelines as well as the professional control of dental biofilm, with periodontal scaler, Robinson s brush and prophylactic paste. However, Group 1 returned every month for control procedures; Group 2 every three months and Group 3 after six months. The intervention had a six-month duration (for all the three groups), when all the exams were repeated by another examiner who did not know which group each patient was inserted in. Finally, the research concluded that despite the fact there is no statistically significant difference among the three groups, clinically the patients from the monthly group presented a better response to professional control, with less accumulation of dental biofilm and less rate of gingival inflammation. Thus, the mechanical control of the dental biofilm performed by the professional could not avoid gingival increase, characterized by the raise of probing depth measurement, neither the quantity of keratinized mucosa
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The maintenance of masticatory function is especially important for patients who wear complete dentures due to the limitations of this type of prosthesis. Thus, the bilateral balanced occlusion (BBO) is used to achieve, besides other advantages, greater masticatory efficiency. However, analyzing critically the literature, it is observed that there is not enough scientific evidence that support the BBO as the most appropriate occlusal concept in complete dentures. This way, the purpose of the present study was to verify if complete dentures wearers with BBO present better masticatory efficiency and capacity than those with canine guidance (CG). A double-blind controlled crossover clinical trial was conducted. The sample was made of 24 completely edentulous patients. The subjects wore sets of complete dentures with both occlusal concepts for equal periods of 3 months. Objective data were collected through the masticatory efficiency test, performed by the colorimetric method, in which capsules of a synthetic material enclosing fuchsine- containing granules were used. Subjective data were recorded by patient´s ratings of their chewing function, which is the masticatory ability. No significant statistical difference was found for masticatory efficiency (p=0,0952) and masticatory ability (x2=0,5711/ p=0,4498) between the two occlusal concepts studied, as well as there was no correlation between these two variables (p=0,2985). Based on these results, it seems reasonable to use CG for the setup of complete dentures, since it is an easier and quicker technical procedure, until that future researches can come to complement this question
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Cryopreservation is a process where cells or biological tissues are preserved by freezing at very low temperatures and aims to cease reversibly, in a controlled manner, all the biological functions of living tissues, i.e., maintain cell preservation so that it can recover with high degree of viability and functional integrity. This study aimed to evaluate the influence of cryopreservation on the mesenchymal stem cells originating from the periodontal ligament of human third molars by in vitro experiments. Six healthy teeth were removed and the periodontal cells grown in culture medium containing α-MEM supplemented with antibiotics and 15% FBS in a humidified atmosphere with 5% CO2 at 37° C. Cells isolated from each sample were divided into two groups: Group I - immediate cell culture (not fresh cryopreserved cells) and Group II - cell cryopreservation, during a period of 30 days. Analyses of rates of cell adhesion and proliferation in different groups were performed by counting the cells adhered to the wells, in intervals of 24, 48 and 72 hours after the start of cultivation. The number of cells in each well was obtained by counting viable cells with the use of hemocytometer and the method of exclusion of cells stained by trypan blue. The difference between groups for each of the times was analyzed by Wilcoxon test. Regarding the temporal evolution for each group, analysis was done by Friedman's test to verify the existence of differences between times and, when it existed, the Wilcoxon penalty was applied. The results showed no statistically significant difference between the two groups analyzed in this study. Therefore, we conclude that the cryopreservation process, after a period of 30 days, did not influence the cell type studied, and there was no difference in growth capacity in vitro between the groups
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Lip squamous cell carcinoma (SCC) may develop from a premalignant condition, actinic cheilitis (AC) in 95% of the cases. Both premalignant and neoplastic lip diseases are caused mainly by chronic exposure to the ultraviolet component of solar radiation, especially UVB. This exposure causes disruption of the cell cycle and damage to DNA repair systems, like mismatch repair, altering proteins repair as hMLH1 and hMSH2. This research aimed to investigate the immunohistochemical expression of hMLH1 and hMSH2 proteins in lower lip SCCs and ACs, providing additional information about carcinogenesis of the lower lip. The sample consisted 40 cases of ACs and 40 cases of lower lip SCCs. Histological sections of 3 μm were submitted to immunoperoxidase method, for immunohistochemical analysis of lesions were counted in 1000 cells (positive and negative), data were evaluated both in absolute numbers and percentage of immunostained cells, the latter by assigning scores. Associations of the variables and comparative analysis of biomarker expression were performed by Fisher s exact and Pearson s chi-square, "t" student, one-way ANOVA, Mann- Whitney e Kruskal-Wallis tests. The level of significance was 5%. It was found that, in lower lip SCC, the mean of the proteins was higher in female patients (hMLH1= 369,80 + 223,98; hMHS2 = 534,80 + 343,62), less than 50 years old (hMLH1 = 285,50 + 190,65; hMHS2 = 540,00 + 274,79) and classified as low-grade malignancy (hMLH1 = 264,59 + 179,21; hMHS2 = 519,32 + 302,58), in these data only to sex, for hMLH1 protein, was statistically significant (p=0.034). Comparing the different lesions, we observed that for both hMLH1 and hMSH2 protein, the average of positive epithelial cells decreased as the lesion was graded at later stages. The ACs classified without dysplasia or mild dysplasia had the highest average of immunostained cells (hMLH1 = 721.23 + 88.116; hMHS2 = 781.50 + 156.93). The ACs classified as moderate or severe dysplasia had intermediate values (hMLH1 = 532,86 + 197,72; hMHS2 = 611,14 + 172,48) and SSCs of the lower lip had the lowest averages (hMLH1 = 255,03 + 199,47; hMHS2 = 518,38 + 265,68). There was a statistically significant difference between groups (p<0.001). In conclusion, our data support the hypothesis that changes in immunoexpression of these proteins is related to the process of carcinogenesis of the lower lip
Papel de sinais cromáticos na identificação de parceiros sexuais em sagüi comum (callithrix jacchus)
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The literature concerning color vision shows a trichromatic advantage in detecting ripe fruits and young leaves, but there are contradictory results. There is also the suggestion of this type of vision being adapted to perceive socio-sexual signals. Indeed, Old World primates utilize the skin color of conspecifics as a factor of attraction. But in New World primates there is no record of a coloration signal in the body that can be utilized by other group members. The present study aims to: 1- test whether there is a relation between coloration of body regions and ovulatory cycle in female Callithrix jacchus; 2- Determine if this species uses visual signals to choose mates that are sexually receptive. We collected feces from six females during one month to quantify progesterone concentration by EIA. Body region coloration was measured using a portable spectrometer and modeled to obtain the quantum catch of each photoreceptor, the opponency channels and chromatic distance between the points in units of JND. We recorded the behavior of six males exposed to three pairs of females with a cycling and a non-cycling female in each pair using a transparent plexiglass apparatus. The color of different body regions presented a correlation between progesterone concentration and the yellow-blue and red-green visual axes, with the genitalia as the region showing the highest correlation. The visual axis more apt to see the color variations was the yellow-blue in dichromats, and in trichromats were the red-green to face, yellow-blue to abdomen and both chromatic axes to genitalia. There was no difference in the signal detectability between trichromats and dichromats, but the perception pattern differed between the phenotypes, with a better signal detection by the dichromat phenotype 562 and the trichromat phenotype 543/562. During the behavioral experiments males presented longer gaze duration in periods of experimental manipulation and gaze duration was always longer towards cycling females compared to non-cycling females. Male locomotion during experimental manipulation was greater than in the control only during the periovulatory period of the female, indicating greater excitement. The behavior of cycling females was more active than the behavior of the non-cycling ones regarding locomotion and touching of the plexiglass division of the apparatus. Male gaze duration to cycling females increased with decreasing progesterone concentration, but none of the coloration parameters was correlated to the mate preference exhibited. This coloration signal can transmit information to animals of the group about fertility of female. Different from the intense red of the genitalia swellings of Old World primates, marmoset female genitalia became more bluish-green in the fertile period. Males chose fertile females and were able to visually identify the periovulatory period of females. Choice is related to progesterone concentration, but our results do not show relation between coloration and mate preference. Maybe some behavioral measure is associated with the choice
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De acordo com o Agrianual (2005), a produção citrícola brasileira é de 17,7 milhões de toneladas ano-1,ocupando aproximadamente 1 milhão de hectares no território brasileiro e, deste total, 810 mil hectares localizam-se no Estado de São Paulo. A maioria dos solos brasileiros, inclusive aqueles onde foram instalados os pomares cítricos, apresenta reação ácida. Esta é, sem dúvida, a principal condição desfavorável dos solos e um dos fatores limitantes da produção em solos tropicais. O presente trabalho teve por objetivo estudar o efeito de diferentes modos de aplicação de calcário e de micronutrientes e analisar, de forma comparativa, os custos destes tratamentos em um pomar de laranjeira. O experimento foi desenvolvido na Fazenda Morumbi, município de Estrela D'Oeste-SP, num Argissolo Vermelho-Amarelo. A variedade de laranjeira utilizada foi a 'Natal', enxertada em limão Cravo, com 6 anos de idade e espaçamento 5 x 8 m. O delineamento experimental foi em parcelas subdivididas, com 3 repetições, com 5 tratamentos principais (sem calcário; a necessidade total de calcário (NC) incorporado; NC sem incorporação; ¹/2 NC no primeiro ano + ¹/2 NC no segundo ano e ¹/3 NC no primeiro ano, + ¹/3 NC no segundo ano, + ¹/3 NC no terceiro ano) e dois tratamentos secundários [micronutrientes via solo (FTE-BR 12: 11,5 % de ZnO e B2O3; 1% CuO; 5,4% de Fe2O3; 5,5% de MnO2; 0,2% de MoO3) e micronutrientes via foliar (sulfato de zinco a 0,5% e ácido bórico a 0,08%)], distribuídos em blocos casualizados. Não houve efeito significativo dos modos de aplicação da calagem e de micronutrientes sobre as variáveis avaliadas (produção, sólidos solúveis totais, acidez total titulável). Para massa média do fruto, o efeito significativo aconteceu apenas no primeiro ano, com a calagem em dose única e sem incorporação, e micronutrientes via solo. Concluiu-se que não houve efeito significativo dos modos de aplicação do calcário e dos micronutrientes para produção e massa média dos frutos da laranjeira 'Natal', e a receita líquida foi positiva em todos os tratamentos, sendo que o tratamento 5 [¹/3 da necessidade total de calcário (NC) no 1º ano + ¹/3 da NC no 2º ano, + ¹/3 da NC no 3º ano] apresentou o melhor valor acumulado (U$ 3.721,85 ha-1).
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There is a lack of clinical studies evaluating techniques of functional impression for partially edentulous arches. The aim of this double-blind non-randomized controlled clinical trial was to compare the efficacy of altered cast impression (ACI) and direct functional impression (DFI) techniques. The efficacy was evaluated regarding the number of occlusal units on denture teeth, mucosa integrity at 24-hour follow-up and denture base extension. The sample included 51 patients (female and male) with mean age of 58.96 years treated at Dental Department of UFRN. The patients, exhibiting edentulous maxilla and mandibular Kennedy class I, were divided into two groups (group ACI, n=29; group DFI, n=22). Clinical evaluation was based on the number of occlusal units on natural and/or artificial teeth, mucosa integrity at 24-hour follow-up, and denture base extension. Statistical analysis was conducted using the software SPSS 17.0® (SPSS Inc., Chicago, Illinois). Student T-test was used to reveal association between number of occlusal units and impression technique while chi-square test showed association between mucosa integrity and impression technique. Fischer s exact test was applied for association between denture base extension and impression technique at 95% level of significance. No significant difference was observed between the groups regarding number of occlusal units, mucosa integrity and denture base extension. The altered cast technique did not provide significant improvement in comparison to the direct technique when the number of occlusal units, mucosa integrity and denture base extension
Resumo:
Realizou-se a análise comparativa de custos de produção de feijão, após um ano em sistemas de plantio direto e convencional, no período de inverno, com irrigação por pivô central. Os experimentos foram desenvolvidos na Fazenda Dois Irmãos, em Pereira Barreto (SP), em delineamento experimental de blocos ao acaso, com 11 tratamentos e quatro repetições, para cada sistema de plantio. Os tratamentos constaram de uma testemunha sem N, duas fontes de N (uréia e nitrato de amônio) e cinco dosagens (20, 40, 60, 80 e 100 kg.ha-1 de N), aplicados em cobertura aos 27 dias após a emergência das plantas. Utilizou-se densidade de 15 plantas por metro de linha e 0,50 m entre sulcos, com semeadura realizada em 20/5/2001. Na área do sistema de plantio direto, as plantas daninhas foram dessecadas após o cultivo do milho, e na de plantio convencional, realizaram uma aração e duas gradagens, sendo uma pesada e uma niveladora, no preparo do solo. Durante o desenvolvimento da cultura foram aplicados herbicidas em pós-emergência para o controle do mato. As duas fontes de nitrogênio mostraram efeito positivo na produção de grãos. A análise econômica revelou melhor resultado para uréia, na dose de 60 kg.ha-1 de N, em preparo convencional do solo, com índice de lucratividade de 40,6%. Para o plantio direto, o nitrato de amônio, na base de 40 kg.ha-1 de N, mostrou maior acréscimo na receita e lucratividade de 25,6%.
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In systems that combine the outputs of classification methods (combination systems), such as ensembles and multi-agent systems, one of the main constraints is that the base components (classifiers or agents) should be diverse among themselves. In other words, there is clearly no accuracy gain in a system that is composed of a set of identical base components. One way of increasing diversity is through the use of feature selection or data distribution methods in combination systems. In this work, an investigation of the impact of using data distribution methods among the components of combination systems will be performed. In this investigation, different methods of data distribution will be used and an analysis of the combination systems, using several different configurations, will be performed. As a result of this analysis, it is aimed to detect which combination systems are more suitable to use feature distribution among the components
Resumo:
Com a finalidade de se comparar as propriedades mecânicas do ligamento da patela e do tendão calcâneo foram realizados ensaios de tração em material obtido de 25 cadáveres humanos. A idade dos doadores foi 58 ± 14 anos (33-85), sendo 19 (76%) masculinos e 6 (24%) femininos, 23 brancos (92%) e dois negros (8%). Os materiais foram testados em seus 10 mm centrais, com velocidade de aplicação de carga de 30 mm/min. Foi obtida a área de secção dos corpos de prova para que fossem estudadas as propriedades estruturais e materiais. Foram estudadas as seguintes variáveis: carga máxima (N), tensão(MPa), módulo de elasticidade (MPa), energia (Nm), alongamento absoluto (mm) e específico (%), limite de proporcionalidade (N), além da tensão (MPa) e alongamentos neste ponto. A análise estatística revelou que ambos possuem carga máxima, limite de proporcionalidade e tensão semelhantes (p>0,05). Nas outras variáveis ocorreu diferença significativa (p<0,05) com o tendão calcâneo apresentando valores maiores para energia e alongamento. O módulo de elasticidade, significativamente maior no ligamento da patela (p<0,05), foi a variável que melhor caracterizou a diferença do comportamento mecânico dos dois materiais.
Análise comparativa dos aspectos clínicos, laparoscópicos e histopatológicos da endometriose pélvica
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OBJETIVO: Estabelecer o padrão de normalidade do ritmo de piscar em crianças normais em idade pré-escolar. MÉTODOS: Avaliaram-se 200 crianças de 4 a 6 anos, saudáveis, usando tomada de imagens digitais, nos planos frontal e lateral, em estado de vigília, em posição primária do olhar, estando o objeto de observação localizado na altura da pupila. Para a tomada das imagens foi utilizada uma filmadora Sony Lithium, sendo as mesmas gravadas em fitas 8 mm, transferidas para um computador MacIntosh G4 e processadas pelo programa iMovie, estudando-se: o tempo de abertura e o tempo de fechamento palpebral, o tempo de piscar completo e o ritmo de movimentos palpebrais por minuto, durante 3 minutos. Os resultados foram avaliados por estatística descritiva e gráfico de linhas. RESULTADOS: O piscar completo foi mais freqüente que o incompleto. O ritmo do piscar completo aumenta com o aumento da idade. Para o piscar incompleto, os valores foram semelhantes em todas as idades avaliadas. O tempo de fechamento e de abertura palpebral e o tempo de piscar completo foram semelhantes em meninos e meninas. O tempo de fechamento foi mais lento que o tempo de abertura palpebral. CONCLUSÕES: O ritmo de piscar completo aumenta com a idade. Os tempos de fechamento e de abertura palpebral e o tempo de piscar completo foram semelhantes em ambos os sexos, em todas as idades estudadas, sendo o fechamento mais lento que a abertura palpebral.
Resumo:
INTRODUÇÃO: A histopatologia convencional continua sendo o padrão-ouro no diagnóstico dos melanomas cutâneos, apesar do progresso da imuno-histoquímica e da biologia molecular. Os critérios microscópicos existentes para esse diagnóstico são numerosos, porém nenhum deles é específico para se afirmar que uma determinada lesão é maligna quando ele está presente, ou é benigna na sua ausência. Alguns critérios têm uma relevância maior para o diagnóstico em relação a outros. OBJETIVO: Este estudo propõe uma análise daqueles critérios considerados mais importantes, comparando sua presença em lesões melanocíticas benignas e melanomas. MATERIAL E MÉTODOS: Foram estudadas 33 lesões melanocíticas benignas (nevo de Spitz: 13; nevo de Reed: 6; nevo displásico: 6; nevo congênito: 3; nevo adquirido: 3; nevo combinado: 1; nevo recorrente: 1), bem como 101 casos de melanomas extensivo/superficiais: 25 intra-epidérmicos e 76 invasivos de pequena espessura (< 2 mm). RESULTADOS: Alguns critérios mostraram alta freqüência em lesões benignas, apresentando pouca especificidade, enquanto outros tiveram menor positividade nas benignas, e alta freqüência nas malignas, mostrando sua maior especificidade e importância no diagnóstico dos melanomas. CONCLUSÃO: Os cinco critérios que mostraram diferenças estatisticamente significativas na comparação com as lesões benignas foram (em ordem decrescente de freqüência): 1. proliferação linear de células isoladas na camada basal; 2. início e fim da lesão com células isoladas; 3. melanócitos na camada granular; 4. disseminação pagetóide extensa; 5. nucléolos grandes, irregulares ou múltiplos. Os melanomas de pequena espessura não apresentam parte dos critérios considerados mais importantes, como falta de maturação, necrose e mitoses profundas.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)