508 resultados para 1531


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Agressões de morcegos a pessoas vêm sendo notificadas em várias comunidades amazônicas nesta última década. Isto constitui um risco potencial para a raiva humana transmitida por morcegos. O objetivo deste estudo foi de analisar fatores associados a estas agressões em uma destas comunidades. Foi realizado um estudo transversal em um povoado de garimpeiros na Região Amazônica brasileira (160 habitantes). Foi realizada a captura de morcegos junto às casas e foram enviadas amostras para o laboratório. Das 129 pessoas entrevistas, 41% foram agredidas por morcegos pelo menos uma vez, com 92% das mordidas localizadas nos dedos dos pés. Por meio de regressão logística, encontrou-se que adultos eram agredidos ao redor de quatro vezes mais do que crianças (OR = 3,75, IC: 1,46-9,62, p = 0,036). Homens foram agredidos com maior freqüência do que mulheres (OR = 2,08, IC: 0,90-4,76, p = 0,067). Nove Desmodus rotundus e três morcegos frugívoros foram capturados e resultaram negativos para a raiva. O estudo sugere que, em áreas de garimpo, adultos do sexo masculino têm maior probabilidade de serem agredidos por morcegos. As ações de controle para a raiva humana a serem desenvolvidas nestes lugares devem dar ênfase especial a adultos homens. Recomendam-se mais investigações sobre o modo como o garimpo na Região Amazônica está colocando em risco as pessoas e o ambiente.

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O objetivo deste trabalho foi determinar a digestibilidade verdadeira da lisina HCl e da lisina Sulfato, com galos adultos cecectomizados. Foram utilizados 18 galos Leghorn, cecectomizados, com peso médio de 2,854 kg, e alojados individualmente em gaiolas metálicas durante dez dias. Após os dois primeiros dias de adaptação às baterias, estes animais passaram por um período de cinco dias recebendo ração em dois períodos diários de uma hora cada (manhã, 8 h e tarde, 16 h), com o objetivo de dilatação do papo para evitar regurgitação da ração a ser introduzida. Foi utilizado o método de alimentação forçada, com 12 galos alojados individualmente em gaiolas metálicas com bandejas coletoras de excretas. O delineamento experimental foi inteiramente casualisado com dois tratamentos (duas fontes de lisina), com seis repetições cada. Um ensaio paralelo com 6 aves em jejum foi conduzido para determinação das perdas endógenas/metabólicas das aves. Os teores de aminoácidos das dietas e das excretas foram analisados para a determinação dos coeficientes de digestibilidade verdadeira das lisinas. Os coeficientes de digestibilidade verdadeira, expressos em porcentagem, foram de 97,59% para a lisina HCl e de 98,34% para a lisina sulfato, não diferindo estatisticamente.

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Foi utilizada uma análise de segregação com o uso da inferência Bayesiana para estimar componentes de variância e verificar a presença de genes de efeito principal (GEP) influenciando duas características de carcaça: gordura intramuscular (GIM), em %, e espessura de toucinho (ET), em mm; e uma de crescimento, ganho de peso (g/dia) dos 25 aos 90 kg de peso vivo (GP). Para este estudo, foram utilizadas informações de 1.257 animais provenientes de um delineamento de F2, obtidos do cruzamento de suínos machos Meishan e fêmeas Large White e Landrace. No melhoramento genético animal, os modelos poligênicos finitos (MPF) podem ser uma alternativa aos modelos poligênicos infinitesimais (MPI) para avaliação genética de características quantitativas usando pedigrees complexos. MPI, MPF e MPI combinado com MPF foram empiricamente testados para se estimar componentes de variâncias e número de genes no MPF. Para a estimação de médias marginais a posteriori de componentes de variância e de parâmetros, foi utilizada uma metodologia Bayesiana, por meio do uso da Cadeia de Markov, algoritmos de Monte Carlo (MCMC), via Amostrador de Gibbs e Reversible Jump Sampler (Metropolis-Hastings). em função dos resultados obtidos, pode-se evidenciar quatro GEP, sendo dois para GIM e dois para ET. Para ET, o GEP explicou a maior parte da variação genética, enquanto, para GIM, o GEP reduziu significativamente a variação poligênica. Para a variação do GP, não foi possível determinar a influência do GEP. As herdabilidades estimadas ajustando-se MPI para GIM, ET e GP foram de 0,37; 0,24 e 0,37, respectivamente. Estudos futuros com base neste experimento que usem marcadores moleculares para mapear os genes de efeito principal que afetem, principalmente GIM e ET, poderão lograr êxito.

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Droplets formed at the tip of a tube under the same conditions possess extreme uniformity of form, volume and weight. These properties of liquid drop formation have been known for a long time and consequently many applications for the drop have been found in instrumentation and chemical analysis methods. In the present paper, we report on the analytical use of a dynamic LED-based flow-through optical absorption detector with optical path length controlled by continuous dropping of a solution. This arrangement consists of a flow cell built within a high-intensity red LED (lambda (max)=630 nm). The feasibility of the detector is demonstrated by colorimetric determination of methylene blue, and ammonium by Berthelot's reaction, in a flow-injection system. For ammonium, the reaction forms a blue dye (indophenol) with a maximum absorption at 630-650 nm. The detection limit, considered as 3 times the signal of the blank, is better than 125 mu g l(-1). The small flow cell represents a good combination of optical path length, low volume and fast washout. This detector can be used advantageously in automated methods and can represent a solution to problems of optical detection involving gas bubbles and precipitation of particles in turbidimetric applications.

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Social conflict between mice produces analgesia in the attacked mouse. Both the magnitude and type (opioid or nonopioid) of this analgesia have been related to attack intensity and strain of mouse. In the present study low intensity social conflict (7 bites) did not produce analgesia, whereas high intensity - 30 and 60 bites interactions produced, respectively, short-lasting (5 min) and very short-lasting (1 min) analgesia in Swiss albino mice, when compared with nonaggressive interaction (0 bite). The 30 bites aggressive interaction induced analgesia (AIIA) was not affected by IP injection of either naloxone (5.0 and 7.5 mg/kg) or diazepam (0.5, 1.0, 2.0 and 4.0 mg/kg). However, this attack-induced analgesia was reduced after IP administration of the 5-HT1A agonists, gepirone (0.3 and 3.0 mg/kg) and BAY R 1531 (0.01 mg/kg). These results indicate that the analgesia induced by 30 bites social conflict in Swiss albino mice does not involve opioid and GABA-benzodiazepine (GABA-BZD) mechanisms. In addition, they suggest that high-intensity social conflict activates serotonergic pain modulatory systems that act through 5-HT1A receptors. Copyright (C) 1997 Elsevier B.V.

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The conductivity of H2SiF6-doped emeraldine polymers is studied as a function of temperature in the range 50 less than or equal to T less than or equal to 180 K. The dopant concentration of the samples varies between 0.1 M and 1.0 M. The temperature dependence of the do electrical conductivity gives evidence for a transport mechanism based on variable-range hopping in three dimensions. Using Mott's formula for the de conductivity, physically meaningful values of the density of states at the Fermi energy, the hopping energy and hopping distance are calculated.

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A new method is described for the rapid, sensitive, virtually interference-free, and selective quantitation of cyanogenic glycosides in aqueous extracts using membrane introduction mass spectrometry (MIMS). Selective monitoring, by either conventional MIMS or cryotrap-MIMS, not of HCN but of the co-released ketones (acetone and butan-2-one), when performed for both the crude cassava extracts and the linamarase-NaOH-hydrolyzed extracts, is found to offer an advantageous alternative to classic spectrophotometric methods based on HCN analysis for the selective quantitation of the two cyanogenic glycosides linamarin and lotaustralin expressed as both the free HCN content and the total cyanogenic potential (total HCN).

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1. 1. Under normoxic conditions at 25°C Pomacea lineata, free to move into or out of water, showed an increase in O2 consumption with increase in body size (dry wt), the slope of the log-log plot of these two parameters being b = 0.76. 2. 2. The metabolic rate decreased with weight. 3. 3. Males and females in a sexually receptive state did not exhibit significantly different QO2 values. 4. 4. The metabolic rates of animals when under water using ctenidium did not differ significantly from when out of water using the lung. © 1981.

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We study the existence of periodic solutions in the neighbourhood of symmetric (partially) elliptic equilibria in purely reversible Hamiltonian vector fields. These are Hamiltonian vector fields with an involutory reversing symmetry R. We contrast the cases where R acts symplectically and anti-symplectically. In case R acts anti-symplectically, generically purely imaginary eigenvalues are isolated, and the equilibrium is contained in a local two-dimensional invariant manifold containing symmetric periodic solutions encircling the equilibrium point. In case R acts symplectically, generically purely imaginary eigenvalues are doubly degenerate, and the equilibrium is contained in two two-dimensional invariant manifolds containing nonsymmetric periodic solutions encircling the equilibrium point. In addition, there exists a three-dimensional invariant surface containing a two-parameter family of symmetric periodic solutions.

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This study evaluated the efficacy of dietary vitamin C (ascorbic acid or AA), vitamin E (α-tocopherol or α-T), and C + E supplementation on the blood parameters of Arapaima gigas grown in net cages for 45 days. Four treatments were tested: control (commercial feed); C800; E500 and C + E (800 + 500) with supplementation of 800 mg AA kg- 1, 500 mg α-T kg- 1 and 800 + 500 mg AA + α-T kg- 1, respectively. Hematocrit (Ht), red blood cells (RBC), and hemoglobin concentration (Hb) (oxidative status indicators), thrombocytes and leukocytes (immunological indicators), plasma protein and glucose were evaluated. Fish fed vitamin C and C + E supplemented diets showed greater weight gain and survival. Dietary vitamin C and C + E diet supplementation resulted in increased Ht, Hb, RBC, MCHC, total leukocytes, total proteins, thrombocytes and eosinophils compared to the control and α-T. The α-tocopherol-supplemented diet reduced the number of total thrombocytes, lymphocytes and neutrophils and increased glucose and eosinophils relatively to the control. In general, leukocytes and thrombocytes were good indicators of the efficiency of vitamin on the defense mechanism of the A. gigas reared in cages. Results indicate that high α-T diet supplementation provides no benefit for the maintenance of the oxidative or the immunological status of A. gigas. However, it was demonstrated that high dietary AA improves A. gigas immunological status. Red blood cell indices and immune system indicators showed no synergistic effect between the vitamins after supplementing the A. gigas diet with α-T + AA. © 2006 Elsevier Inc. All rights reserved.

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The aim of this work was to evaluate the effect of physical preconditioning in the responsiveness of rat pulmonary rings submitted to lung ischemia/reperfusion (IR). Wistar rats were divided into three groups: Sedentary sham-operated (SD/SHAM); sedentary submitted to ischemia/reperfusion (SD/IR) and trained submitted to ischemia/reperfusion (TR/IR) animals. Exercise training consisted in sessions of 60 min/day running sessions, 5 days/week for 8 weeks. Left pulmonary IR was performed by occluding for 90 min and reperfusing for 120 min. After that, pulmonary arteries were isolated and concentration-response curves to acetylcholine (ACh), histamine (HIST), sodium nitroprusside (SNP), phenylephrine and U46619 were obtained. Neither potency (- log EC50) nor maximal responses (Emax) were modified for ACh and HIST in all groups. On the other hand, the potency for SNP was significantly increased in TR/IR group (8.23 ± 0.06) compared to SD/IR group (7.85 ± 0.04). Contractile responses mediated by a-adrenergic receptor were markedly decreased in IR groups (SD/IR: 6.75 ± 0.06 and TR/IR: 6.62 ± 0.04) compared to SD/SHAM (7.33 ± 0.05). No changes were seen for the U46619 in all groups. In conclusion, the present study shows that exercise training has no protective actions in the local blood vessel where the IR process takes place. © 2006 Elsevier Inc. All rights reserved.

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The genus Paratrechina (Motschulsky) is composed of about 147 cosmopolitan ant species and subspecies, of which some were accidentally spread by commerce around the world, infesting houses and hospitals. In Brazil, two species are of remarkable economic importance: Paratrechina fulva (Mayr) and Paratrechina longicornis (Latreille). The present paper aims to report the following aspects on the biology of P. longicornis: number of larval instars, growth rates, duration and viability of the developmental stages and some observations on brood-care behaviour. Artificial colonies were kept under controlled temperature (25±2°C) and relative humidity (60±10%) conditions. To access the number of larval instars, we analyzed 1531 larvae fixed in Dietrich by measuring their maximum head capsule widths. We analysed ten artificial colonies daily to measure the developmental time and viability of immatures. We found P. longicornis presented three larval instars and a mean growth ratio of 1.2988. Egg stage was found to last 16.1 ±0.1 days, with a viability of 24.6%; larval stages were found to last 18.3±0.1 days, with a viability of 33.3% and the pupal stage was found to last 12.3±0.1 days, with a viability of 65.3%.

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Incluye Bibliografía

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Aim: Several typing methods for Candida spp. have been suggested in the literature in order to distinguish isolates for studies about the virulence or infection routes of these microorganisms and, in particular, for epidemiological purposes. The aim of this study was to establish a comparison between the phenotypic profile of oral Candida isolates from periodontitis patients and control individuals. Methods: The morphotyping and biotyping of 35 C. albicans isolates obtained from chronic periodontitis patients and 48 isolates from control individuals were performed. For morphotyping, the isolates were plated on malt extract agar and incubated for 10 days. Sixteen different morphotypes were observed for C. albicans, the most frequently observed being 0000 and 0001. Results: Biotype 0000 (complete absence of fringe) was most prevalent among the isolates obtained from periodontitis patients compared to those from control individuals, with statistical significance. Biotyping revealed 5 different biotypes with higher prevalence of the biotype 357 among the isolates from control and periodontitis groups. Conclusions: The results obtained by biotyping of the isolates did not permit to differentiate a characteristic model related to periodontal disease, whilst the morphotype 0000 was most frequently isolated from periodontitis patients.