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Expression in Escherichia coli of a dominant immunogen of Trypanosoma cruzi recognized by human chagasic sera. 下载免费PDF全文
P C Cotrim G S Paranhos R A Mortara J Wanderley A Rassi M E Camargo J F da Silveira 《Journal of clinical microbiology》1990,28(3):519-524
A genomic clone expressing a Trypanosoma cruzi antigen in Escherichia coli was identified using human chagasic sera. Chagasic antibodies affinity purified on extracts of this clone recognized a high-molecular-weight protein expressed in all developmental stages of the parasite life cycle, as well as in various T. cruzi strains. The antigen is associated with the cytoskeleton of the parasite and localizes along the attachment region between the flagellum and the cell body. Antibodies to the recombinant antigen were detected in the sera of 115 chagasic patients from different endemic regions, but not in sera of patients with leishmaniasis, T. rangeli infection, or other parasitic diseases. Our data suggest that the presence of antibodies to this antigen may be specifically associated with Chagas' disease. 相似文献
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Andrade MM Tomé MF Santiago ES Lúcia-Santos A de Andrade TG 《Physiology & behavior》2003,78(1):125-133
We conducted a longitudinal study about daily variation of Wistar male rats' behavior in the elevated plus-maze (EPM) evaluated in the 1st, 2nd, 3rd, 6th, 12th, and 18th months of life. Animals were submitted to the plus-maze in 12 sessions at 2-h intervals (n=72, 6 per time point). Spontaneous rest-activity rhythm of four animals was assessed by observation of 24-h videotape records. Time series were analyzed by Cosinor method. Behavioral rates on the six occasions and in light and dark phases were compared by means of two-way ANOVA with repeated measures. Exploratory behavior in EPM was smaller in the light phase and in older animals. Higher values of open and closed arms exploration were observed in the first and third months of the dark phase, and in the first month of the light phase. Adjustment to the 24-h period was significant at all stages for rest-activity data, number of entries in closed arms, and time on center, and for three to five stages for open-arm exploration. In general, 24 h variability was more pronounced in younger animals compared with older ones. The present study showed that: (1). a significant amount of total variability of the behavioral indexes analyzed could be attributed to 24 h variation, (2). light/dark phases differences in EPM exploration were present at all developmental stages, (3). older Wistar rats explored less the EPM and were less active in their home cage compared with younger ones, and (4). behavioral indexes (EPM) decrease was phase related and partially related to a reorganization of rest-activity rhythm. 相似文献
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Christophe Cornu Maria-Izabel Almeida Silveira F. Goubel 《European journal of applied physiology》1997,76(3):282-288
The objective of this work was to study the effects of plyometric training on the mechanical properties of the ankle joint
in humans. Changes in the mechanical parameters of this musculo-articular structure were quantified with the aid of a sinusoidal
perturbation technique. This technique allowed the expression of the mechanical impedance of the musculo-articular system
in terms of stiffness, viscosity and inertia. Measurements were performed under passive conditions and when the subject performed
plantar flexion. A 7-week period of training induced a decrease in the slope of the relationship between stiffness and plantar
flexion torque, whereas passive stiffness was increased. A slight decrease in viscosity and an invariability in inertia were
also found. These results are interpreted in terms of the possible adaptations of the musculo-articular structure and ultrastructure
involved in the performance of plantar flexion.
Accepted: 11 April 1997 相似文献
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The use of specialized coils to improve signal-to-noise ratios in magnetic resonance (MR) imaging is an important innovation. The role of surface coils has not yet been well defined, but it seems likely that they will be routinely used for clinical imaging of the orbit, neck, and spine. Surface coils have important limitations that make other designs, such as "closely coupled" volume coils, attractive for some applications, especially for limb imaging. With improvement in our ability to visualize anatomy with MR imaging, specialized radio frequency coils may provide new imaging capabilities for clinical problems that were not previously considered to be indications for diagnostic imaging. 相似文献
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Stamborowski Sadi Fernando de Oliveira Spinelli Bruna Moreira Lima Fernanda Pupio Silva Costa Davidson Ribeiro de Silveira Souza Gabriela Aparecida Lima Mario Oliveira Lopes Martins Rodrigo Alvaro Brandão 《Lasers in medical science》2021,36(8):1741-1749
Lasers in Medical Science - Physical activity raises body temperature. However, the literature does not contain studies about whether the employment of hotobiomodulation (PMB) could significantly... 相似文献
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Fabrício Silveira Ana Luísa Martins Paulo Gadelha Rmulo Paes-Sousa 《Bulletin of the World Health Organization》2021,99(3):228
The extended scope and complexity of the United Nations 2030 agenda entail important challenges for the operationalization of the health-related sustainable development goal (SDG) indicators. Divergences in concepts, agendas and implementation strategies among institutions have fostered the parallel development of alternative and concurrent indicators. We aim to determine the convergences and divergences between five key institutions: the Global Burden of Disease Study (GBD), the Pan American Health Organization, the Sustainable Development Solutions Network, the World Bank and the World Health Organization (WHO). Of the 104 health-related indicators listed by these five institutions, 60 are consistent with official Inter-agency and Expert Group SDG indicators. Our analysis considers the indicators included, and the themes these indicators cover, in each institution list and each institution online platform. We quantified convergence in indicators between the institutions themselves, but also between the institutions and the official Inter-agency and Expert Group. Our results indicate important divergences; only 22 of the 60 indicators are included in the lists of all five institutions. The level of adoption of the official metrics varies from 40.5% (15/(47−10)) for the GBD to 86.2% (25/(29−0)) for the World Bank. WHO, the official curator of the Inter-agency and Expert Group SDG indicators, is only convergent with the official metrics by 72.1% (31/(45−2)). Our analysis, and the resulting awareness of the differences, potentialities and limitations of indicators and platforms, provides important contributions to enable the achievement of the health-related SDGs and deliver the promise of the 2030 agenda. 相似文献