963 resultados para Ex?menes de ingl?s


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(Anatomical analysis of peach palm (Bactris gasipaes) leaves cultivated in vitro, ex vitro and in vivo). The present work characterized and compared the anatomical structures of the leaves of Bactris gasipaes (Arecaceae) plants grown under different cultivation conditions (in vitro, ex vitro and in vivo) with the goal of identifying the origins of the difficulties encountered in acclimatizing micro-plants. The Quant program was used to determine leaf tissue thicknesses and areas, and histochemical tests were performed on leaf sections and analyzed using light microscopy. Stomatal and trichome densities were determined using the epidermal impression method and by scanning electronic microscopy. Our results indicated that there were no discernible alterations of the anatomical characteristics of the leaves of micro-plants cultivated under differing conditions and that the thickening of the mesophyll and the vascular fibers indicated adaptive responses to ex vitro conditions. As such, the observed difficulties in acclimatizing peach palm micro-plants to ex vitro conditions cannot be attributed to plant anatomical characteristics acquired during in vitro cultivation.

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This paper describes an outbreak of chytridiomycosis affecting a group of Dendrobates tinctorius, a Neotropical anuran species, confiscated from the illegal wildlife trade and housed in a private zoo in Brazil as part of an ex situ breeding program. We examined histological sections of the skin of 30 D. tinctorius and 20 Adelphobates galactonotus individuals. Twenty D. tinctorius (66.7%) and none of the A. galactonotus were positive for Batrachochytrium dendrobatidis (Bd). Multiple development stages of Bd infection were observed. The reasons for the interspecific difference in the rate of infection could not be determined, and further studies are advised. Because the examined population consisted of confiscated frogs, detailed epidemiological aspects could not be investigated, and the source of the fungus remains uncertain. The existence of ex situ amphibian populations is important for protecting species at higher risk in the wild, and ex situ amphibian conservation and breeding programs in Brazil may be established using confiscated frogs as founders. However, this paper alerts these programs to the urgency of strict quarantine procedures to prevent the introduction of potential pathogens, particularly Bd, into ex situ conservation programs.

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The nutritional management of seedlings in the nursery is one of the most important practices that influence seedling quality. The aim of this work was to evaluate the effect of nitrogen, phosphorus and potassium on the development of Schizolobium amazonicum seedlings grown in 250 cm(3) containers with a commercial substrate in the North of Mato Grosso State, Brazil. The experimental design was completely randomized design with five treatments and five replications, each replication being represented by 24 seedlings. The treatments were: control (only commercial substrate); nitrogen fertilization (150 g m(-3) N using ammonium sulfate + 1.0 kg of ammonium sulfate dissolved in 100 L of water and applied in coverage); phosphorus fertilization (300 g P2O5 m(-3) using simple superphosphate); potassium fertilization (100 g m(-3) K2O using potassium chloride + 0.3 kg of potassium chloride dissolved in 100 L of water and applied in coverage) and; complete (a mixture of the three nutrients, 150, 300 and 100 g m(-3) N, P2O5 and K2O, respectively + 1.0 kg of ammonium sulfate + 0.3 kg of potassium chloride). The commercial substrate was composted milled pine bark plus vermiculite. Evaluations of the seedlings were performed at 90 days after sowing. The complete treatment (NPK) gave the highest values for biometric and best plant indices, which express the quality. When analyzing nutrients in isolation; potassium had the lowest effect. Based on these results it can be recommended to fertilize Schizolobium amazonicum seedlings in nurseries with 150, 300 and 100 g m(-3) of N, P2O5 and K2O, respectively, plus 1.0 kg of sulfate ammonium and 0.3 kg of potassium chloride applied in coverage.

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The success of endodontic treatment depends on the complete elimination of microorganisms from the root canal system, thus the search for new procedures to eliminate them is justified. The aim of this study was to assess bacterial reduction after intracanal irradiation with the Er:YAG laser. The canals of 70 extracted human maxillary canines were prepared up to file #40 using 1% NaOCl, irrigated with 17% EDTA, and then washed with physiological solution activated by ultrasound. The roots were sterilized by autoclaving, inoculated with 10 mu l of a suspension containing 1.5 x 10(8) CFU/ml of Enterococcus faecalis ATCC 29212 and incubated at 37A degrees C for 72 h. The canals were irradiated with the Er:YAG laser using two energy settings: 60 mJ and 15 Hz, and 100 mJ and 10 Hz. The remaining bacteria were counted immediately and 48 h after laser irradiation. The results showed a high bacterial reduction at both time points. With 60 mJ and 15 Hz there was an immediate reduction of 99.73% and the reduction was 77.02% after 48 h, and with 100 mJ and 10 Hz there was an immediate reduction of 99.95% and the reduction was 84.52% after 48 h. Although the best results were observed with 100 mJ of energy, the difference between the two settings was not statistically significant. The count performed 48 h after irradiation showed that E. faecalis were able to survive, and can grow even from small numbers.

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In this study, we isolated the alkaloid erysothrine from the hydroalcoholic extract of flowers from E. mulungu and screened for its anticonvulsant and anxiolytic actions based on neuroethological and neurochemical experiments. Our results showed that the administration of erysothrine inhibited seizures evoked by bicuculline, PTZ, NMDA and most remarkably, kainic acid. Also, erysothrine induced an increase in the number of entries but not in the time spent in the open arms of the EPM. However, we did not notice any alterations in the light-dark choice or in the open-field tests. In preliminary neurochemistry tests, we also showed that erysothrine (0.001-10 mu g/mL) did not alter the GABA or glutamate synaptossomal uptake and binding. Altogether, our results describe an alkaloid with anticonvulsant activity and mild anxiolytic activity that might be considered well tolerated as it does not alter the general behavior of the animals in the used doses. (C) 2012 Elsevier Inc. All rights reserved.

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Objective: The aim of this study was to evaluate, ex vivo, the precision of five electronic root canal length measurement devices (ERCLMDs) with different operating systems: the Root ZX, Mini Apex Locator, Propex II, iPex, and RomiApex A-15, and the possible influence of the positioning of the instrument tips short of the apical foramen. Material and Methods: Forty-two mandibular bicuspids had their real canal lengths (RL) previously determined. Electronic measurements were performed 1.0 mm short of the apical foramen (-1.0), followed by measurements at the apical foramen (0.0). The data resulting from the comparison of the ERCLMD measurements and the RL were evaluated by the Wilcoxon and Friedman tests at a significance level of 5%. Results: Considering the measurements performed at 0.0 and -1.0, the precision rates for the ERCLMDs were: 73.5% and 47.1% (Root ZX), 73.5% and 55.9% (Mini Apex Locator), 67.6% and 41.1% (Propex II), 61.7% and 44.1% (iPex), and 79.4% and 44.1% (RomiApex A-15), respectively, considering ±0.5 mm of tolerance. Regarding the mean discrepancies, no differences were observed at 0.0; however, in the measurements at -1.0, the iPex, a multi-frequency ERCLMD, had significantly more discrepant readings short of the apical foramen than the other devices, except for the Propex II, which had intermediate results. When the ERCLMDs measurements at -1.0 were compared with those at 0.0, the Propex II, iPex and RomiApex A-15 presented significantly higher discrepancies in their readings. Conclusions: Under the conditions of the present study, all the ERCLMDs provided acceptable measurements at the 0.0 position. However, at the -1.0 position, the ERCLMDs had a lower precision, with statistically significant differences for the Propex II, iPex, and RomiApex A-15.

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Abstract Background Banana cultivars are mostly derived from hybridization between wild diploid subspecies of Musa acuminata (A genome) and M. balbisiana (B genome), and they exhibit various levels of ploidy and genomic constitution. The Embrapa ex situ Musa collection contains over 220 accessions, of which only a few have been genetically characterized. Knowledge regarding the genetic relationships and diversity between modern cultivars and wild relatives would assist in conservation and breeding strategies. Our objectives were to determine the genomic constitution based on Internal Transcribed Spacer (ITS) regions polymorphism and the ploidy of all accessions by flow cytometry and to investigate the population structure of the collection using Simple Sequence Repeat (SSR) loci as co-dominant markers based on Structure software, not previously performed in Musa. Results From the 221 accessions analyzed by flow cytometry, the correct ploidy was confirmed or established for 212 (95.9%), whereas digestion of the ITS region confirmed the genomic constitution of 209 (94.6%). Neighbor-joining clustering analysis derived from SSR binary data allowed the detection of two major groups, essentially distinguished by the presence or absence of the B genome, while subgroups were formed according to the genomic composition and commercial classification. The co-dominant nature of SSR was explored to analyze the structure of the population based on a Bayesian approach, detecting 21 subpopulations. Most of the subpopulations were in agreement with the clustering analysis. Conclusions The data generated by flow cytometry, ITS and SSR supported the hypothesis about the occurrence of homeologue recombination between A and B genomes, leading to discrepancies in the number of sets or portions from each parental genome. These phenomenons have been largely disregarded in the evolution of banana, as the “single-step domestication” hypothesis had long predominated. These findings will have an impact in future breeding approaches. Structure analysis enabled the efficient detection of ancestry of recently developed tetraploid hybrids by breeding programs, and for some triploids. However, for the main commercial subgroups, Structure appeared to be less efficient to detect the ancestry in diploid groups, possibly due to sampling restrictions. The possibility of inferring the membership among accessions to correct the effects of genetic structure opens possibilities for its use in marker-assisted selection by association mapping.

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Gracilaria domingensis (Kützing) Sonder ex Dickie and Gracilaria birdiae (Plastino & Oliveira) (Gracilariales, Rhodophyta) are seaweeds that occur on the Brazilian coast. Based on their economic and pharmaceutical importance, we investigated the antioxidant activity of the methanolic, ethyl acetate and hexane extracts of both species. The hexane extracts display a high antioxidant activity and comparative analyses indicated G. birdiae as the most active species. Chemical investigation of these fractions showed several carotenoids and fatty acids, as well as cholesterol and sitosterol derivatives. HPLC-DAD analysis of G. birdiae showed violaxanthin (0.04 μg.mg-1 of dry material), antheraxanthin (5.31 μg.mg-1), aloxanthin (0.09 μg.mg-1), zeaxanthin (0.45 μg.mg-1) and β-carotene (0.37 μg.mg-1) as the major carotenoids. G. domingensis showed a similar carotenoid profile, however, with much lower concentration than G. birdiae. Gas chromatography coupled to mass spectrometry was used to determine other nonpolar compounds of these seaweeds. The main compounds detected in both studied species were the fatty acids 16:0; 18:1 Δ9; 20:3 Δ6,9,12, 20:4 Δ5,8,11,14. We found no specificity of compounds in either species. However, G. birdiae, presented higher contents of carotenoids and arachidonic acid than G. domingensis.

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The aim of this research was to evaluate the bioremediation of a soil contaminated with wastes from a plasticizers industry, located in São Paulo, Brazil. A 100-kg soil sample containing alcohols, adipates and phthalates was treated in an aerobic slurry-phase reactor using indigenous and acclimated microorganisms from the sludge of a wastewater treatment plant of the plasticizers industry (11gVSS kg-1 dry soil), during 120 days. The soil pH and temperature were not corrected during bioremediation; soil humidity was corrected weekly to maintain 40%. The biodegradation of the pollutants followed first-order kinetics; the removal efficiencies were above 61% and, among the analyzed plasticizers, adipate was removed to below the detection limit. Biological molecular analysis during bioremediation revealed a significant change in the dominant populations initially present in the reactor.

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Thermal treatment (thermal rectification) is a process in which technological properties of wood are modified using thermal energy, the result of which is often value-added wood. Thermally treated wood takes on similar color shades to tropical woods and offers considerable resistance to destructive microorganisms and climate action, in addition to having high dimensional stability and low hygroscopicity. Wood samples of Eucalyptus grandis were subjected to various thermal treatments, as performed in presence (140ºC; 160ºC; 180ºC) or in absence of oxygen (160ºC; 180ºC; 200ºC) inside a thermal treatment chamber, and then studied as to their chemical characteristics. Increasing the maximum treatment temperatures led to a reduction in the holocellulose content of samples as a result of the degradation and volatilization of hemicelluloses, also leading to an increase in the relative lignin content. Except for glucose, all monosaccharide levels were found to decrease in samples after the thermal treatment at a maximum temperature of 200ºC. The thermal treatment above 160ºC led to increased levels of total extractives in the wood samples, probably ascribed to the emergence of low molecular weight substances as a result of thermal degradation. Overall, it was not possible to clearly determine the effect of presence or absence of oxygen in the air during thermal treatment on the chemical characteristics of the relevant wood samples.

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O transplante pulmonar consolidou-se como a melhor opção terapêutica para diversas pneumopatias terminais. O baixo número de doadores viáveis ainda persiste como uma grande limitação ao aumento do número de transplantes de pulmão, causando alta mortalidade na lista de espera. Diferentemente do transplante de outros órgãos sólidos, a maior limitação do transplante pulmonar não é o número absoluto de doadores e sim a viabilidade desses órgãos, que é reduzida devido às agressões ao pulmão ocasionadas pela morte encefálica e aos cuidados na UTI. Diversas são as propostas para o aumento do número de doadores: intensificação das campanhas de doação, o uso de doadores com coração parado, transplante pulmonar lobar intervivos e maior flexibilidade dos critérios para aceitação de doadores de pulmão. Todavia, a proposta que atrai a atenção de diversos grupos de transplante pulmonar é a perfusão pulmonar ex vivo, principalmente pela perspectiva de recuperação de pulmões inicialmente descartados. Esse sistema consiste na reperfusão e ventilação do bloco pulmonar isolado em um circuito de circulação extracorpórea modificado. Devido aos bons resultados apresentados e à perspectiva de aumento no número de órgãos aptos a transplante, diversos grupos têm estudado a técnica. Pesquisadores na Suécia, Canadá, Áustria, Inglaterra, Espanha e Brasil já possuem experiência sólida com o método e introduziram algumas variações. O objetivo deste artigo foi revisar o desenvolvimento, o estado da arte e as perspectivas futuras do modelo ex vivo de perfusão e recondicionamento pulmonar.

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INTRODUÇÃO: Os pacientes que apresentam perda poderal maciça evoluem com sobras dermogordurosas em várias áreas corporais, incluindo os membros inferiores. Diante da heterogeneidade de localização, forma e conteúdo das dismorfias coxofemorais, este trabalho oferece um roteiro de planejamento e sistematização para tratamento de cada uma das deformidades. MÉTODO: Foram avaliadas 28 pacientes do sexo feminino que realizaram coxoplastias e que apresentavam basicamente 3 tipos de deformidade, que poderiam envolver apenas o terço superior, os terços superior e médio ou toda a face medial das coxas. Para cada tipo de deformidade foi aplicada técnica específica; além disso, quando necessário, foi associada suspensão da face lateral das coxas e lipoaspiração. A satisfação das pacientes com os resultados cirúrgicos foi avaliada por meio da aplicação de questionários e notas atribuídas a cada resposta. Foram enumerados intercorrências, complicações e tratamento aplicado. RESULTADOS: Os itens mobilidade, higiene, desempenho sexual, vestimentas e cicatrizes foram avaliados como ótimo (80,5%), bom (14,5%) e regular (5%). CONCLUSÕES: Considerando-se a grande heterogeneidade de dismorfias das coxas em pacientes ex-obesos, um roteiro de tratamento relacionando a deformidade ao tratamento deve ser incorporado ao arsenal cirúrgico.

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O presente estudo objetiva traçar um panorama atual sobre a responsabilidade subsidiária dos sócios nas hipóteses em que, em fase de execução no processo do trabalho, os bens da pessoa jurídica sejam insuficientes para satisfação dos créditos. A matéria propriamente dita nada tem de nova, remontando aos primeiros decretos que regulamentavam as sociedades por quotas de responsabilidade limitada, passando pelo Código Civil de 1916 e de 2002. Todavia, o estudo procurará demonstrar que, aos poucos, foi sendo abandonada a exigência de comprovação dos amplos poderes de mando e gestão do sócio, ou seu exercício abusivo, assim como foi aumentando simultaneamente a preocupação com a figura dos ex-sócios, objeto de investigação especial no presente trabalho. O artigo sustentará a tese de que essa maior liberdade na interpretação da responsabilidade de sócios e ex-sócios se deve, sobretudo, (a) à promiscuidade patrimonial verificada entre pessoas jurídicas e pessoas naturais, na sociedade brasileira, (b) às altíssimas taxas de encerramento das pessoas jurídicas logo no primeiro ou no segundo ano de existência e (c) à elevada rotatividade de sócios nos estatutos da empresa.

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[ES] Kappaphycus alvarezii (Doty) Doty ex Silva ha sido cultivada en Cativá, localizado en la zona costera del caribe panameño, al noreste del Canal de Panamá, desde el 2004 con intereses comerciales. El cultivo fue desarrollado en dos partes: el cultivo in situ (en el mar y en tanques) y el cultivo in vitro (en el laboratorio y en aclimatación en tanques y acuarios). Ambas cultivos tienen como objetivo obtener un desarrollo sostenible en la zona costera y un producto atractivo para la industria que dé oportunidades económicas a los cultivadores. Los resultados muestran que la tasa de crecimiento observada (4.0 a 5.0 %) permanece constante durante todo el año y es independiente de los sitios seleccionados, de las temporadas: lluviosa y seca, y de los parámetros ambientales. Ya que menos de una hectárea ha sido cultivada y existen 40 disponibles, esto multiplica grandemente la posibilidad de explotación. En cuanto a los sistemas de plantación, las estructuras fijas causan menos impacto, son menos costosas y son beneficiosas para el crecimiento. Además, Kappaphycus alvarezii puede ser mantenida en tanques con tasas de crecimiento similares a las naturales, por lo tanto puede ser usada como biomasa para semillas. El secador usado, dio un cantidad estimada de 36 sacos de 11 Kg. de biomasa seca cada uno, materia prima por polígono (300 m2) año-1. La producción de carragena mantiene un patrón constante (ca. 35%) en relación a la producción y al peso molecular aceptado por la industria (1.6 105 Da). La producción de diferentes fracciones, iota y kappa, varía con el tiempo de cultivo, siendo mayor en talos jóvenes para la primera y menor para en los más viejos para la segunda. Las técnicas de los cultivos in vitro permiten el mantenimiento y propagación de stocks de fragmentos de explantos en el laboratorio y aclimatados en tanques y acuarios. La aclimatación ex vitro ha demostrado ser factible para la recuperación y futura propagación de los explantos mantenidos en el laboratorio a sitios en el mar.