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971.
Emma Wilson Emiliano Rustighi Philip L. Newland Brian R. Mace 《Biomechanics and modeling in mechanobiology》2013,12(3):581-596
The isometric force response of the locust hind leg extensor tibia muscle to stimulation of a slow extensor tibia motor neuron is experimentally investigated, and a mathematical model describing the response presented. The measured force response was modelled by considering the ability of an existing model, developed to describe the response to the stimulation of a fast extensor tibia motor neuron and to also model the response to slow motor neuron stimulation. It is found that despite large differences in the force response to slow and fast motor neuron stimulation, which could be accounted for by the differing physiology of the fibres they innervate, the model is able to describe the response to both fast and slow motor neuron stimulation. Thus, the presented model provides a potentially generally applicable, robust, simple model to describe the isometric force response of a range of muscles. 相似文献
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de Abreu Filipe Vieira Santos Macedo Mariana Viana da Silva Alex Junio Jardim de Oliveira Cirilo Henrique de Ottone Vinícius Oliveira de Almeida Marco Antônio Barreto dos Santos Edmilson da Cardoso Jader Cruz Campos Aline Scarpellini da Silva Claudia Maria Dornelles da Silva Amanda Gonzales de Andrade Miguel Souza Bernis Valéria Magro Octaviano Bernis Filho Walter Octaviano de Trindade Giliane Souza Albuquerque George Rego da Sevá Anaiá Paixão Ribeiro Bergmann Morais Teixeira Danilo Simonini Campos Fabrício Souza Franco Ana Cláudia Roehe Paulo Michel de Oliveira Danilo Bretas 《EcoHealth》2021,18(4):414-420
EcoHealth - In 2019, a new coronavirus disease (COVID-19) was detected in China. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was capable to infect domestic and captive mammals like... 相似文献
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Cell mediated immunity in American cutaneous and mucosal leishmaniasis 总被引:18,自引:0,他引:18
E M Carvalho W D Johnson E Barreto P D Marsden J L Costa S Reed H Rocha 《Journal of immunology (Baltimore, Md. : 1950)》1985,135(6):4144-4148
Cellular immune responses were studied in 35 Brazilian patients with either active cutaneous leishmaniasis (CL), active mucosal leishmaniasis (ML), or healed cutaneous leishmaniasis. The mean age and duration of illness in the two groups were as follows: 14 CL patients, age 28 +/- 13 yr, disease 5 +/- mo; and 16 ML patients, age 34 +/- 15 yr, disease 86 +/- 117 mo. Patients with CL and ML responded well to leishmania antigen in blastogenesis assays. However, the response of ML patients was over three times greater than the response of CL patients. There was a significant correlation between the magnitude of the lymphoproliferative response and the duration of disease activity. There were no significant differences between CL and ML patients in terms of the following parameters: lymphoproliferative responsiveness to mitogens (phytohemagglutinin, concanavalin A, and pokeweed mitogen) and peripheral blood lymphocyte subpopulations (T and B cells, oKT8+ and OKT4+ cells, OKT4:OKT8 ratio). Peripheral blood mononuclear cells from ML patients also generated interferon-gamma containing lymphokine in response to stimulation with leishmania antigen. This lymphokine was capable of inducing macrophages from ML patients to inhibit the intracellular multiplication of leishmania in vitro. These studies have determined that the parameters of lymphocyte and macrophage functions evaluated in ML and CL patients are comparable, except for an enhanced lymphoproliferative response, with leishmania antigen in ML patients. This later finding may be a function of the long duration of active disease in this population and unrelated to the pathogenesis of their mucosal lesions. 相似文献
976.
Vergara-Tabares David L. Toledo Martín García Emiliano Peluc Susana I. 《Oecologia》2018,188(1):173-182
Oecologia - Frugivorous birds are able to track spatiotemporal changes in fruit availability. Food resource fluctuations, characteristic of seasonal environments, can be affected by the... 相似文献
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Gabriel de Souza Colombo Isis Viana Mendes Betúlia de Morais Souto Cristine Chaves Barreto Luana Assis Serra Eliane Ferreira Noronha Nádia Skorupa Parachin João Ricardo Moreira de Almeida Betania Ferraz Quirino 《Letters in applied microbiology》2022,74(6):941-948
The current climate crisis demands replacement of fossil energy sources with sustainable alternatives. In this scenario, second-generation bioethanol, a product of lignocellulosic biomass fermentation, represents a more sustainable alternative. However, Saccharomyces cerevisiae cannot metabolize pentoses, such as xylose, present as a major component of lignocellulosic biomass. Xylose isomerase (XI) is an enzyme that allows xylose consumption by yeasts, because it converts xylose into xylulose, which is further converted to ethanol by the pentose-phosphate pathway. Only a few XI were successfully expressed in S. cerevisiae strains. This work presents a new bacterial XI, named GR-XI 1, obtained from a Brazilian goat rumen metagenomic library. Phylogenetic analysis confirmed the bacterial origin of the gene, which is related to Firmicutes XIs. After codon optimization, this enzyme, renamed XySC1, was functionally expressed in S. cerevisiae, allowing growth in media with xylose as sole carbon source. Overexpression of XySC1 in S. cerevisiae allowed the recombinant strain to efficiently consume and metabolize xylose under aerobic conditions. 相似文献
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