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排序方式: 共有1811条查询结果,搜索用时 31 毫秒
31.
de Sousa Karolini Tenffen Deniz Matheus Moro Matheus Fernando Gomes Isabelle Cordova do Vale Marcos Martinez Dittrich João Ricardo 《International journal of biometeorology》2021,65(10):1781-1786
International Journal of Biometeorology - Lying behavior is an important indicator of the cows’ welfare and health. In this study, we evaluate the effect of the physical environment on dairy... 相似文献
32.
Volpi Denise Alves Fabiana Villa da Silva Arguelho Alan do Vale Marcos Martinez Deniz Matheus Zopollatto Maity 《International journal of biometeorology》2021,65(10):1695-1705
International Journal of Biometeorology - The aim of this study was to estimate, using data mining, which microclimate and behavioral variables affect the behavior of animals to seek shaded or... 相似文献
33.
Leduc Antoine O. H. C. Costa Jessica S. Oliveira do Nascimento Silva Renata R. Winandy Gabrielle S. M. de Araújo Carlos B. 《Journal of Ethology》2021,39(2):225-234
Journal of Ethology - Noise pollution may impair the cognitive performances of several animal species, producing suboptimal behavioral responses. Involuntary shifts in attention from noise... 相似文献
34.
Maria Rita Pegado Catarina Santos Ana Couto Eduarda Pinto Ana Rita Lopes Mário Diniz 《Marine and Freshwater Behaviour and Physiology》2013,45(6):347-357
ABSTRACTSharks have been facing unprecedented pressure over the last decades, and ocean acidification may represent an additional threat, particularly during their most susceptible life stages. Hence, the present study aimed to investigate the effects of ocean acidification (control pCO2 ~ 400 μatm; high pCO2 ~ 900 μatm) on the growth, swimming performance and cholinergic system of juvenile white-spotted bamboo sharks (Chiloscyllium plagiosum). After 45 days of exposure, we observed that high CO2 did not affect most of the end-points studied. However, somatic growth rate and the percentage of time that sharks spent swimming was significantly reduced under high CO2 conditions. Moreover, AChE activity decreased in two of the seven brain macroareas analyzed, the telencephalon and optic lobes. As this near-threatened shark species showed small sub-lethal effects to high CO2 levels, we argue that within a longer time-frame they can potentially reduce individual performance with cascading consequences to shark population dynamics. 相似文献
35.
Joana A. Loureiro Sandra Rocha Maria do Carmo Pereira 《Journal of peptide science》2013,19(9):581-587
The amyloid β‐peptide with a sequence of 42 amino acids is the major constituent of extracellular amyloid deposits in Alzheimer's disease plaques. The control of the peptide self‐assembly is difficult to achieve because the process is fast and is affected by many variables. In this paper, we describe the effect of different charged and non‐charged surfactants on Aβ(1‐42) fibrillation to define common alternate aggregation pathways. The characterization of the peptide‐surfactant interactions by ultra‐structural analysis, thioflavin T assay and secondary structure analysis, suggested that charged surfactants interact with Aβ(1‐42) through electrostatic interactions. Charged micelles slow down the aggregation process and stabilize the peptide in the oligomeric state, whereas non‐charged surfactants promote the Aβ(1‐42) fibril formation. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
36.
Thiago Moreno L. Souza Paola C. Resende Natalia Fintelman-Rodrigues Tatiana Schaffer Gregianini Nilo Ikuta Sandra Bianchini Fernandes Ana Luisa Furtado Cury Maria do Carmo Debur Rosa Marilda M. Siqueira 《PloS one》2013,8(11)
Although surveillance efforts that monitor the emergence of drug-resistant strains of influenza are critical, systematic analysis is overlooked in most developing countries. We report on the occurrence of strains of pandemic influenza A(H1N1)pdm09 with resistance and decreased susceptibility to oseltamivir (OST) in Brazil in 2009, 2011 and 2012. We found 7 mutant viruses, 2 with the mutation S247N and other 5 with the mutation H275Y. Most of these viruses were from samples concentrated in the southern region of Brazil. Some of these resistant viruses were detected prior to the initiation of OST treatment, suggesting that community transmission of mutant viruses may exist. Moreover, we show that one of these OST-resistant (H275Y) strains of A(H1N1)pdm09 was discovered in the tri-border region between Brazil, Argentina and Paraguay, highlighting that this strain could also be found in other Latin American countries. Our findings reinforce the importance of enhanced antiviral resistance surveillance in Brazil and in other Latin American countries to confirm or rule out the community transmission of OST-resistant strains of A(H1N1)pdm09. 相似文献
37.
Matheus Balduíno Goncalves dos Reis Letícia Correa Manjolin Claudia do Carmo Maquiaveli Osvaldo Andrade Santos-Filho Edson Roberto da Silva 《PloS one》2013,8(11)
Epigallocatechin-3-gallate (EGCG), a dietary polyphenol (flavanol) from green tea, possesses leishmanicidal and antitrypanosomal activity. Mitochondrial damage was observed in Leishmania treated with EGCG, and it contributed to the lethal effect. However, the molecular target has not been defined. In this study, EGCG, (+)-catechin and (−)-epicatechin were tested against recombinant arginase from Leishmania amazonensis (ARG-L) and rat liver arginase (ARG-1). The compounds inhibit ARG-L and ARG-1 but are more active against the parasite enzyme. Enzyme kinetics reveal that EGCG is a mixed inhibitor of the ARG-L while (+)-catechin and (−)-epicatechin are competitive inhibitors. The most potent arginase inhibitor is (+)-catechin (IC50 = 0.8 µM) followed by (−)-epicatechin (IC50 = 1.8 µM), gallic acid (IC50 = 2.2 µM) and EGCG (IC50 = 3.8 µM). Docking analyses showed different modes of interaction of the compounds with the active sites of ARG-L and ARG-1. Due to the low IC50 values obtained for ARG-L, flavanols can be used as a supplement for leishmaniasis treatment. 相似文献
38.
Caio Cesar de Souza Alves Adam Collison Luke Hatchwell Maximilian Plank Matthew Morten Paul S. Foster Sebastian L. Johnston Cristiane Fran?a da Costa Mauro Vieira de Almeida Henrique Couto Teixeira Ana Paula Ferreira Joerg Mattes 《PloS one》2013,8(11)
Background
Severe asthma is associated with T helper (TH) 2 and 17 cell activation, airway neutrophilia and phosphoinositide-3-kinase (PI3K) activation. Asthma exacerbations are commonly caused by rhinovirus (RV) and also associated with PI3K-driven inflammation. Anthraquinone derivatives have been shown to reduce PI3K-mediated AKT phosphorylation in-vitro.Objective
To determine the anti-inflammatory potential of anthraquinones in-vivo.Methods
BALB/c mice were sensitized and challenged with crude house dust mite extract to induce allergic airways disease and treated with mitoxantrone and a novel non-cytotoxic anthraquinone derivative. Allergic mice were also infected with RV1B to induce an exacerbation.Results
Anthraquinone treatment reduced AKT phosphorylation, hypoxia-inducible factor-1α and vascular endothelial growth factor expression, and ameliorated allergen- and RV-induced airways hyprereactivity, neutrophilic and eosinophilic inflammation, cytokine/chemokine expression, mucus hypersecretion, and expression of TH2 proteins in the airways. Anthraquinones also boosted type 1 interferon responses and limited RV replication in the lung.Conclusion
Non-cytotoxic anthraquinone derivatives may be of therapeutic benefit for the treatment of severe and RV-induced asthma by blocking pro-inflammatory pathways regulated by PI3K/AKT. 相似文献39.
Paulo Ricardo Porfírio do Nascimento Daniella Regina Arantes Martins Glória Regina Góis Monteiro Paula Vivianne Queiroz Francisco Paulo Freire-Neto José Wilton Queiroz ádila Lorena Morais Lima Selma Maria Bezerra Jeronimo 《PloS one》2013,8(10)
Leishmania infantum infection in humans and dogs can evolve with a wide range of clinical presentations, varying from asymptomatic infections to visceral leishmaniasis. We hypothesized that the immune response elicited by L. infantum infection could modulate whether the host will remain asymptomatic or progress to disease. A total of 44 dogs naturally infected with L. infantum were studied. Leishmania burden was estimated in the blood and spleen by qPCR. The expression of IFN-γ, TNF-α, IL-10 and Iron Regulatory Protein 2 (IRP2) were determined in the spleen by quantitative PCR. Sera cytokines were evaluated by ELISA. Dogs were grouped in quartiles according parasite burden. Increased expression of IFN-γ and TNF-α was associated with reduced Leishmania burden, whereas increased IL-10 and IRP2 expressions were associated with higher Leishmania load. Increased plasma albumin and IFN-γ expression explained 22.8% of the decrease in parasite burden in the spleen. These data confirm that lower IFN-γ response and higher IL-10 correlated with increased parasite load and severity of the visceral leishmaniasis in dogs. The balance between the branches of immune response and the intracellular iron availability could determine, in part, the course of Leishmania infection. 相似文献
40.
Paulo Roque Obreli-Neto Leonardo Régis Leira Pereira Camilo Molino Guidoni André de Oliveira Baldoni Srecko Marusic Divaldo Pereira de Lyra-Júnior Kelsen Luis de Almeida Ana Claudia Montolezi Pazete Janaina Dutra do Nascimento Mitja Kos Edmarlon Girotto Roberto Kenji Nakamura Cuman 《PloS one》2013,8(12)