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排序方式: 共有3293条查询结果,搜索用时 15 毫秒
31.
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Pincivero DM Coelho AJ Erikson WH 《The Journal of sports medicine and physical fitness》2000,40(4):319-326
BACKGROUND: 1) To examine the validity and accuracy of the CR-10 scale for evaluating perceived exertion, and 2) to assess gender differences in perceived exertion across different levels of contraction intensity. METHODS: Experimental design: cross-sectional, comparative design. Setting: Human Performance and Fatigue Laboratory, Eastern Washington University. Subjects: 30 healthy, college age volunteers (15 males, 15 females). Measures: All subjects were assessed for isometric torque and perceived exertion of the quadriceps femoris muscles, via the CR-10 scale. One low anchor was applied under resting conditions with the knee flexed to 60 degrees, and a high anchor was applied during a maximal voluntary muscle contraction (MVC). Subjects performed five-second isometric contractions equivalent to 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90% of their MVC, in a random order, and were assessed for perceived exertion by visually observing the CR-10 scale. One sample "t"-tests and 95% confidence intervals were calculated for perceived exertion at each relative torque level. A single factor ANOVA with repeated measures was performed across al levels of exercise intensity. Linearity for perceived exertion was assessed via regression analysis. RESULTS: Perceived exertion at each exercise intensity were as follows: 10%: 1.87+/-1.14, 20%: 2.43+/-1.19, 30%: 3.5+/-1.36, 40%: 3.97+/-1.52, 50%: 4.73+/-1.28, 60%: 5.53+/-1.28, 70%: 6.73+/-1.62, 80%: 7.57+/-1.72, and 90%: 8.6+/-1.52. The increase in perceived exertion across the intensity spectrum was found to fit both linear and quadratic trends. There were no gender differences in perceived exertion across all levels of exercise intensity. CONCLUSIONS: The findings demonstrate that the CR-10 scale closely approximates perceived exertion of the quadriceps femoris muscles during sub-maximal, static contractions, and is not gender specific. 相似文献
33.
Elma Izze da Silva Magalhes Bianca Rodrigues de Oliveira Lívia Carolina Sobrinho Rudakoff Vitria Abreu de Carvalho Poliana Cristina de Almeida Fonseca Viola Soraia Pinheiro Machado Arruda Carolina Abreu de Carvalho Carla Cristine Nascimento da Silva Coelho Maylla Luanna Barbosa Martins Bragana Heloisa Bettiol Marco Antnio Barbieri Viviane Cunha Cardoso Alcione Miranda dos Santos Renata Bertazzi Levy Antnio Augusto Moura da Silva 《Nutrients》2022,14(15)
Longitudinal studies evaluating the relationship between UPF consumption and the incidence of Metabolic Syndrome (MetS) and its components are still scarce. This study aimed to evaluate the effect of UPF consumption on the incidence of MetS and its components in adults. A prospective study was conducted with 896 participants from the 1978/79 Ribeirão Preto cohort, São Paulo, Brazil. UPF consumption was evaluated in %kcal and %g at ages 23–25 years. Incidence of MetS and its components were estimated at ages 37–39 years, according to the Joint Interim Statement criteria. Poisson regression was used to assess associations, and interactions with sex were investigated. UPF consumption had no association with MetS (%kcal Adjusted PR: 1.00; 95% CI: 0.99–1.01; %g Adjusted PR: 1.00; 95% CI: 0.99–1.01). However, women with higher UPF consumption, in %kcal and %g, had a higher risk of abdominal obesity (%kcal: p = 0.030; %g: p = 0.003); and women with higher UPF consumption, in %g, had a higher risk of low HDL-cholesterol (p = 0.041). For the other components of MetS, no significant associations were observed in either sex. These findings suggest evidence of no association between UPF consumption and MetS; however, consumption of UPF was associated with increased WC and low HDL-c, but only in women. 相似文献
34.
35.
Pereira M. G. Vilaça M. Pereira M. Ferreira G. Monteiro S. Coelho H. Geraldes C. Gonçalves C. da Costa F. Leal Marques H. Bacalhau R. 《Quality of life research》2020,29(10):2641-2650
Quality of Life Research - The diagnosis of multiple myeloma (MM) has a significant impact on patients. This study analyzed the mediating role of patients’ unmet needs in the relationship... 相似文献
36.
Pitiguara de Freitas Coelho Roberta Ribeiro Batista Barbosa Rodrigo dos Santos Lugao Fernanda Mayrink Gonalves Liberato Pmela Reis Vidal Roberta de Cssia Nunes Cruz Melotti Mrcio Vinícius Fagundes Donadio 《Hong Kong Physiotherapy Journal》2022,42(1):5
Background:Autonomic nervous system balance is altered in cystic fibrosis (CF), although its influence on physical fitness has been poorly explored.Objective:This study aimed to evaluate the association of heart rate variability (HRV) with exercise capacity and levels of daily physical activity in children and adolescents with mild-to-moderate CF.Methods:A cross-sectional study including individuals with CF aged 6–18 years, not under CFTR modulator therapy, was performed. Sociodemographic (age, sex) and clinical information (airway colonization, pancreatic insufficiency, and genotyping) were collected. In addition, exercise capacity (modified shuttle test — MST), lung function (spirometry), body composition (bioimpedance), levels of daily physical activity (5-day accelerometer), and HRV (both at rest and during the MST) were evaluated.Results:30 individuals (20 females) aged years, mean FEV%, were included. A sympathovagal balance (LF/HF) increase () during the MST was shown, indicating a predominance of sympathetic modulation. The standard deviation of all RR intervals (SDNN) and the high frequency (HF) index during exercise correlated significantly with FEV1 (, and , ; respectively). MST distance also correlated positively and significantly with SDNN (, ), square root of the mean of the sums of squares of frequencies between RR intervals greater than 50 ms — RMSSD (, ), low frequency — LF (, ), HF (, ), dispersion of points perpendicular to the short-term identity line — SD1 (, ) and negatively with LF/HF (, ). Regarding daily physical activity, SDNN at rest (, ) and exercise (, ) showed positive correlations with time in moderate-to-vigorous activities. When normalizing the SDNN and classifying individuals as normal or altered, those presenting altered SDNN showed poorest FEV1 () and lower exercise capacity ().Conclusion:HRV correlates with lung function, exercise capacity and levels of daily physical activity in children and adolescents with CF. The study highlights the influence of CF on autonomic function and suggests HRV measurement as an easy tool to be used in clinical settings as an alternative marker to monitor CF individuals. 相似文献
37.
Juliana Moscardini Chavasco Bárbara Helena Muniz Prado E Feliphe Claudio Daniel Cerdeira Fabrício Damasceno Leandro Luiz Felipe Leomil Coelho Jéferson Junior da Silva Jorge Kleber Chavasco Amanda Latercia Tranches Dias 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(1):13-20
The antimicrobial activity of plant hidroethanolic extracts on bacteria
Gram positive, Gram negative, yeasts, Mycobacterium tuberculosis H37
and Mycobacterium bovis was evaluated by using the technique of Agar
diffusion and microdilution in broth. Among the extracts evaluated by Agar diffusion,
the extract of Bidens pilosa leaf presented the most expressive
average of haloes of growth inhibition to the microorganisms, followed by the extract
of B. pilosa flower, of Eugenia pyriformis'' leaf
and seed, of Plinia cauliflora leaf which statistically presented
the same average of haloes inhibitory formation on bacteria Gram positive, Gram
negative and yeasts. The extracts of Heliconia rostrata did not
present activity. Mycobacterium tuberculosis H37 and
Mycobacterium bovis (BCG) appeared resistant to all the extracts.
The susceptibility profile of Candida albicans and
Saccharomyces cerevisiae fungi were compared to one another and
to the Gram positive Bacillus subtilis, Enterococcus
faecalis and the Gram negative Salmonella typhimurium
bacteria (p > 0.05). The evaluation of cytotoxicity was carried
out on C6-36 larvae cells of the Aedes albopictus mosquito. The
extracts of stem and flower of Heliconia rostrata, leaf and stem of
Plinia cauliflora, seed of Anonna crassiflora
and stem, flower and root of B. pilosa did not present toxicity in
the analyzed concentrations. The highest rates of selectivity appeared in the
extracts of stem of A. crassiflora and flower of B.
pilosa to Staphylococcus aureus, presenting potential
for future studies about a new drug development. 相似文献
38.
Cristina Martins Coelho Larissa Almeida Campos Fabiana Oliveira Pereira Ranieri Monteiro Cardoso Lucas Mendes Nascimento Jessica Blanc Leite Oliveira 《The Journal of asthma》2018,55(1):73-78
Considering the complex relationship between asthma symptoms and exercise, asthmatics are usually believed to be less active in daily life than healthy subjects. However, few studies have objectively assessed daily-life physical activity (DLPA) of asthmatic adults. Objective: To objectively assess DLPA of a sample of Brazilian asthmatic women in comparison to healthy controls, and to investigate the associations between DLPA and asthma control, health-related quality of life, anxiety and depression levels, and the Six-minute walk test (6MWT) in this population. Methods: Sixty-six women were included, 36 in the asthma group (AG) and 30 in the control group (CG). The AG was composed by clinically stable moderate-to-severe asthmatics. The CG was composed by apparently healthy volunteers. All subjects underwent DLPA assessment (considered as the average of steps taken during six consecutive days measured by a pedometer) and performed the 6MWT. Additionally, participants in the AG were assessed using the Asthma Control Questionnaire, the Asthma Quality of Life Questionnaire (AQLQ), and the Hospital Anxiety and Depression Scale. Results: There was no difference between the AG and the CG regarding DLPA (7490.3 ± 3330.2 vs 6876.4 ± 3242.1 steps respectively, p = 0.45), even after adjustment for covariates. DLPA was significantly correlated to the activity limitation domain of the AQLQ among asthmatics (r = 0.43, p < 0.01). Conclusion: Despite the association between self-perceived activity limitation and DLPA among asthmatics, there were no differences regarding DLPA between a sample of moderate-to-severe Brazilian asthmatic women and apparently healthy controls. 相似文献
39.
Bettina Stolp Andrea Imle Fernanda Matos Coelho Miroslav Hons Roser Gorina Ruth Lyck Jens V. Stein Oliver T. Fackler 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(45):18541-18546
HIV-1 negative factor (Nef) elevates virus replication and contributes to immune evasion in vivo. As one of its established in vitro activities, Nef interferes with T-lymphocyte chemotaxis by reducing host cell actin dynamics. To explore Nef’s influence on in vivo recirculation of T lymphocytes, we assessed lymph-node homing of Nef-expressing primary murine lymphocytes and found a drastic impairment in homing to peripheral lymph nodes. Intravital imaging and 3D immunofluorescence reconstruction of lymph nodes revealed that Nef potently impaired T-lymphocyte extravasation through high endothelial venules and reduced subsequent parenchymal motility. Ex vivo analyses of transendothelial migration revealed that Nef disrupted T-lymphocyte polarization and interfered with diapedesis and migration in the narrow subendothelial space. Consistently, Nef specifically affected T-lymphocyte motility modes used in dense environments that pose high physical barriers to migration. Mechanistically, inhibition of lymph node homing, subendothelial migration and cell polarization, but not diapedesis, depended on Nef’s ability to inhibit host cell actin remodeling. Nef-mediated interference with in vivo recirculation of T lymphocytes may compromise T-cell help and thus represents an important mechanism for its function as a HIV pathogenicity factor. 相似文献
40.
Viral respiratory infection in Curitiba, Southern Brazil 总被引:1,自引:0,他引:1