1000 resultados para Divisão celular
Resumo:
Não disponível
Resumo:
The use of pesticides in Brazil has intensified over the years. And since 2009 it was ranked as the largest market for pesticides worldwide. The consequential diffuse contamination of the environment is therefore due to the increasing number of chemicals of different classes, origins and modes of action. Little is known about the action of pesticides on human health in situations of co-exposure. Possible toxic effects are not restricted to agricultural and industrial workers, but also the general population that may be exposed continuously to its residues in food and water. Although these pesticides are mostly present in the environment at low doses, it must be considered that possible cumulative or synergistic effects may occur when there are concurrent or sustained exposure for two or more of these agents, which can lead to late manifestation of subclinical damages, sometimes irreversible. Thus, the specific objective of this study was to assess the effect of carcinogenesis promotion of a mixture of pesticides at low doses and analyze the phenomena of cell proliferation and apoptosis in rat liver. A total of 50 male Lewis rats was separated into 5 groups for 8 weeks in a medium term hepatocarcinogenesis model. The three different classes of pesticides (dieldrin, dicofol, endosulfan, dichlorvos and permethrin), whose residues were detected by ANVISA during the period from 2001 to 2005 in tomatoes cultures, were added to the feed of rats initiated to hepatocarcinogenesis with diethylnitrosamine (DEN- 200mg/kg ip). We used two different mixtures, one with no toxic effects at doses (MEX1) referring to the NOEL (no-observed-effect level) and another at doses LOEL / LEL / LOAEL (Lowest-observed-effect level / Lowest-effect level / Lowest -observed-adverse-effect level), to the installation of adverse effects (MEX2), derived from chronic studies. All animals ...(Complete abstract click electronic access below)
Resumo:
Tabebuia avellanedae Lorentz ex Griseb (ipê-roxo), Bignoniaceae, ocorre na Floresta Tropical Atlântica e é de grande importância, uma vez que, devido às suas propriedades medicinais e lenho de grande valor comercial, já esteve sob ameaça de extinção. A mistura de reguladores vegetais é conhecida como bioestimulante que pode incrementar o desenvolvimento vegetal, estimulando a divisão, a diferenciação e o alongamento celular. Assim, neste trabalho avaliou o efeito da aplicação da mistura de reguladores vegetais do grupo das auxinas, giberelinas e citocininas no desenvolvimento de plantas jovens de ipê-roxo. Os tratamentos foram: testemunha, GA4+7 + BAP 100 mg L-1, GA4+7 + BAP 200 mg L-1, GA3 + IBA + cinetina 0,5% e GA3 + IBA + cinetina 1,0% os quais foram aplicados 4 vezes em intervalos de 30 dias. O efeito dos tratamentos foi avaliado pelas medidas de altura das plantas, diâmetro do caule, número de folhas, massa seca das folhas, caule e raízes e avaliação de trocas gasosas. O tratamento com GA3 + BAP 200 mg L-1 foi aquele que apresentou maior efeito no crescimento das plantas. Já para as avaliações fotossintéticas o tratamento com GA3 + IBA + cinetina foi aquele que apresentou a maior taxa de assimilação de CO2
Resumo:
Articular cartilage is the structure that coats the bone ends in regions where two bones are articulated, allowing movement. It has inefficient intrinsic and extrinsic mechanisms of repair, usually resulting in fibrocartilage formation after injury. Such repair have lower strength, stiffness and usability features when compared to hyaline cartilage. The mesenchymal stem cells have the potential to regenerate tissue without the production of scar, and because of this feature it is well studied. But to have its maximum chondrogenic potential, it is necessary to use scaffolds and growth factors. Biomaterials play the role of scaffold for the cells allowing them to become attached, grow and produce extracellular matrix, leading to formation of repair with hyaline cartilage. In this sense, the purpose of this study is to provide information on the various studies using cell therapy and / or biomaterials to produce hyaline cartilage
Resumo:
Nos últimos anos, as pesquisas com células-tronco têm despertado um grande interesse nos meios de comunicação, levando a população a encarar esse novo conhecimento científico como sendo um método promissor para a cura de inúmeras doenças até agora, tidas como incuráveis. Deste modo, mostra-se fundamental que o ensino de Biologia se volte para o desenvolvimento de competências que permitam ao aluno entender, discutir, questionar, analisar, adquirir um posicionamento crítico diante das informações postas e fazendo uso dos conhecimentos adquiridos, servir como multiplicadores do conhecimento científico. Este trabalho tem como objetivo central a produção de um material didático contendo informações a respeito das células-tronco, quanto aos tipos, características, classificações, métodos de coleta e as terapias desenvolvidas no Brasil. Informações estas que servem como auxílio para professores de Ciências e Biologia, na compreensão e atualização perante as inovações científicas relacionadas às células-tronco. O capítulo 6 vem como uma sugestão de atividades possíveis a serem desenvolvidas a partir desse tema. Apresenta ainda um CD-ROM contendo uma síntese do assunto proposto a servir como suporte no preparo de aulas didáticas relacionadas ao tema
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Pós-graduação em Medicina Veterinária - FCAV
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Two treatment options are available for adult patients with skeletal Class II malocclusion caused by mandibular deficiency: combined mandibular advancement surgery and orthodontic treatment or mandibular advancement appliance. This study aimed to analyze the effects of two therapeutic modalities of Class II malocclusion treatment with mandibular deficiency. Two distinct individuals with Class II malocclusion division 1 and mandibular deficiency were treated after growth spurt. The first individual used the Herbst appliance as a therapeutic option and the second individual was treated with bilateral sagittal osteotomy. The cephalometric, occlusion and face results were evaluated for both individuals. Correction of Class II malocclusion was observed on both Herbst and surgery patients resulting on a normal occlusal relationship with normal overjet and overbite. Therefore it was concluded that Herbst appliance can be used to treat borderline skeletal Class II in adult patients.
Resumo:
In this study, it is proposed to evaluate the anteroposterior position of mandible in children with Angle Class II, division 1 malocclusions, to compare two different methods of evaluating the jaw position and verifying the correlation between these two methods. We selected 26 Brazilian children with vertical growth pattern and Angle Class II, division 1 malocclusions, aged between 7 years and 8 months to 9 years and 6 months. The evaluation of the anteroposterior position of the mandible was performed with the use of lateral cephalograms by cephalometric angular SNB and linear Pog-Nperp. Based on the results obtained, it was concluded that the SNB identified more children with mandibular retrusion than Pog-Nperp; the increased tip of the SN plane may have decreased values of SNB; Pog-Nperp minimizes the possibility of error in the anteroposterior position of the mandible, since it eliminates the variable tip of the anterior skull base (SN plane); none of the cephalometric measurements used are able to eliminate the influence of the nasion point in the anterior-posterior and vertical position; correlation between SNB and Pog-Nperp is very low.
Resumo:
The aim of this study was to evaluate the facial profile changes due to natural growth and induced by Herbst appliance and Bionator in the treatment of Class II, division 1 malocclusion. In order to do that, we used a sample of 90 lateral radiographs of 45 individuals in pre-pubertal stage, divided up in two experimental groups and one control. The first group, composed of 15 brazilian individuals, with initial mean age of 9.4 years, was treated with the Herbst appliance for a period of seven months. The second experimental group consisting of 15 brazilian individuals, initial mean age of 9.9 years has gone through bionator therapy for an average period of 21 months. The control group of 15 individuals, who were not treated orthodontically, comes up from the Burlington Growth Centre, University of Toronto, Canada. The intragroup comparison was performed using the Student t test and intergroup comparisons by ANOVA complemented by the Bonferroni test. The results have shown that only the group treated with the Herbst appliance presented significant changes in facial profile with improvement of its convexity and lower lip protrusion.
Resumo:
The current reports the case of a young patient with malocclusion Class II division 1 on permanent dentition treated in two stages, rthopedics and orthodontics, respectively. At first, the banded Herbst appliance was used duringa 7 months period, followed by a T4K appliance, Trainer for Kids used as retention, and on the second stage the corrective Orthodontics was performed. The results showed the acquirement of a Class I dental relationship, which was kept stable, with excellent intercuspation, even after 5 years of the removal of the Herbst appliance, as well as the correction of the overjet and the reduction of the facial profile convexity. It can be concluded that the Herbst appliance was very efficient in correcting the Class II malocclusion, long term, also providing a very favorable effect on the facial profile.