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1.
The ACE I/D polymorphism has been associated with longevity, although not consistently. The objective of this study was to detect the possible unequal distribution of the alleles and genotypes of this polymorphism among centenarians and younger segments of the population. Relevant data were extracted from studies in the literature, comparing genotype and allele frequencies between centenarians and younger controls. The association of ACE I/D polymorphism with exceptional longevity was analyzed in a total of 1803 centenarians and 10,484 controls using the chi-square test with the Yates correction. We conducted combined analyses for all ethnic groups studied in the literature (Caucasian, Chinese and Korean) as well as for Caucasians only. The DD genotype (odds ratio (OR): 1.25 (95% confidence interval (CI): 1.02–1.54), P = 0.032) and the D-allele were more frequent in Caucasian centenarians compared with their younger controls (OR: 1.16 (95% CI: 1.05–1.28), P < 0.001). Similar findings were obtained when all ethnic origin groups were included in the analyses, with no evidence of publication bias or heterogeneity (P > 0.05). The present meta-analysis indicates that the ACE D-allele and the DD genotype might confer a modest, albeit significant advantage to reach exceptional longevity.  相似文献   
2.
GeroScience - The rs1333049 (G/C) polymorphism located on chromosome 9p21.3 is a candidate to influence extreme longevity owing to its association with age-related diseases, notably coronary artery...  相似文献   
3.
There is a lack of simple field methods for obtaining accurate and reliable information on energy expenditure (EE) during physical activity. This study aims to investigate the validity of the YMCA Submaximal Cycle Ergometer Test to predict EE at submaximal intensities. Twenty-eight participants of each sex volunteered for the study and performed a maximal oxygen uptake (VO(2)max) incremental test, a submaximal exercise test (three 5-min loads at 40%, 55%, and 70% VO(2)max) and the YMCA Test that provides an extrapolation based on heart rate (HR) to predict VO(2) (YMCA VO(2)-HR). Results indicate that predicted VO(2)max from the YMCA Test was significantly different from the gold standard. However, predicted VO(2) at different relative submaximal intensities did not significantly differ from directly measured VO(2). In conclusion, the HR method using the YMCA VO(2)-HR relationship appears to be effective in predicting EE at submaximal intensities but not at maximum efforts.  相似文献   
4.
Ventilatory efficiency during exercise in healthy subjects   总被引:8,自引:0,他引:8  
When evaluating dyspnea in patients with heart or lung disease it is useful to measure the quantity of ventilation needed to eliminate metabolically produced CO2 (i.e., the ventilatory efficiency). Mathematically, the relationship between ventilation (VE) and CO2 output is determined by the arterial CO2 pressure and the physiologic dead space-tidal volume ratio. We decided to determine how age, sex, size, fitness, and the type of ergometer influenced ventilatory efficiency in normal subjects. Three methods were compared for expressing this relationship: (1) the VE versus CO2 output slope below the ventilatory compensation point, commonly used by cardiologists for estimating the severity of heart failure; (2) the VE/CO2 output ratio at the anaerobic threshold, commonly used by pulmonologists; and (3) the lowest VE/CO2 output ratio during exercise, the latter parameter not previously reported. We studied 474 healthy adults, between 17 and 78 years of age during incremental cycle and treadmill cardiopulmonary exercise tests at three test sites, correcting the total VE for the equipment dead space. The lowest VE/CO2 output ratio was insignificantly different from the ratio at the anaerobic threshold, less variable than that for the slope relationship, and unaffected by the site, ergometer, and gas exchange measurement systems. The regression equation for the lowest VE/CO2 output ratio was 27.94 + 0.108 x age + (0.97 = F, 0.0 = M) - 0.0376 x height, where age is in years and height is in centimeters. We conclude that the lowest VE/CO2 output ratio is the preferred noninvasive method to estimate ventilatory inefficiency.  相似文献   
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6.
Article Abstract

The purpose of this investigation was to determine if the critical swimming velocity (CSV), defined as the theoretical maximal swimming velocity that could be maintained for a long period of time without exhaustion, corresponds to the exercise intensity at onset blood lactate accumulation (OBLA), and if it could be utilized as a practical index for assessing endurance performance in elite physically disabled swimmers. Eight elite physically disabled swimmers swam four different distances (50, 100, 200 and 400 m) at maximal effort. The swimming time was taken during each trial. The CSV was expressed as the slope of a regression line between the covered swimming distance and the corresponding times of all possible combinations of 2 or 4 time trials. Results indicate that all the CSVs calculated were similar independently of the distances utilized for their calculation. Afterwards, a CSV confirmation test consisting of 3×10-min trials at 95, 100, 105% of the CSV was carried out. The lactate concentration at the end of each trial was 3.32, 4.03 and 5.73 mmol·l?1, respectively. Lactate concentration at 100% CSV approached the value of 4 mmol·l?1, which is considered the exercise intensity at OBLA. We conclude that the CSV corresponds with the OBLA intensity and could be a valuable index to plan a training schedule for physically disabled swimmers.  相似文献   
7.
The purpose of this study was to analyze the effects of 2 days/week versus 4 days/week of Whole Body Vibration (WBV) during eight weeks of WBV training on health-related quality of life (SF-36), balance and lower body strength, as well as short-term detraining (3 weeks) on balance and lower body strength among older adults. Thirty-four older adults were randomly assigned to a control group (Control; n = 11) or to one of the vibration training groups: WBV 2 days/week (WBV_2d; n = 11) or WBV 4 days/week (WBV_4d; n = 12). The WBV groups exercised for 8 weeks, following 3 weeks of detraining. Lower body strength increased significantly (p < 0.05) for both groups, WBV_2d and WBV_4d, after 8-week training. A significant reduction in strength was observed following 3 weeks of detraining only in WBV_2d group (p < 0.05). All variables of the SF-36 and the balance test did not change after intervention in any group. 2 days/week and 4 days/week of WBV during 8 weeks showed the same improvements on muscle strength. 3 weeks of detraining did not reverse the gains in strength made during 32 sessions of WBV.

Key points

  • 2 days and 4 days per week of WBV training during 8 weeks showed the same improvements on muscle strength.
  • 3 weeks of detraining did not reverse the gains in strength made during 32 sessions of WBV exercise.
  • 3 weeks of detraining did reverse the gains in strength made during 16 sessions of WBV exercise.
Key words: Whole-body vibrations, posturography, dose-response, equilibrium  相似文献   
8.
9.
To determine whether 10 weeks of whole‐body vibration (WBV) training has a significant effect on strength, muscle mass, muscle power, and mobility in older women, 26 subjects were randomly assigned to a WBV training group (n=13; mean age 79 years) and a control (CON) group (n=13; mean age 76 years). Maximal voluntary isometric contraction (MVIC) increased 38.8% in the WBV group, without changes in the CON group. Electromyographic activity of the vastus medialis (VM), the vastus lateralis, and the biceps femoris (BF) did not change in either group. Thigh muscle cross‐sectional area increased significantly after training in VM (8.7%) and BF (15.5%). Muscle power at 20%, 40%, and 60% MVIC decreased from pre‐test to post‐test in the CON group; however, WBV training prevented the decrease in the WBV group. Consequently, mobility, measured by the Timed Up and Go test, increased significantly after training (9.0%) only in the WBV group. Ten weeks of lower limb WBV training in older women produces a significant increase in muscle strength induced by thigh muscle hypertrophy, with no change in muscle power. The adaptations to WBV found in the present study may be of use in counteracting the loss of muscle strength and mobility associated with age‐induced sarcopenia.  相似文献   
10.
The purpose of this investigation was to determine if the critical swimming velocity (CSV), defined as the theoretical maximal swimming velocity that could be maintained for a long period of time without exhaustion, corresponds to the exercise intensity at onset blood lactate accumulation (OBLA), and if it could be utilized as a practical index for assessing endurance performance in elite physically disabled swimmers. Eight elite physically disabled swimmers swam four different distances (50, 100, 200 and 400 m) at maximal effort. The swimming time was taken during each trial. The CSV was expressed as the slope of a regression line between the covered swimming distance and the corresponding times of all possible combinations of 2 or 4 time trials. Results indicate that all the CSVs calculated were similar independently of the distances utilized for their calculation. Afterwards, a CSV confirmation test consisting of 3×10-min trials at 95, 100, 105% of the CSV was carried out. The lactate concentration at the end of each trial was 3.32, 4.03 and 5.73 mmol·l-1, respectively. Lactate concentration at 100% CSV approached the value of 4 mmol·l-1, which is considered the exercise intensity at OBLA. We conclude that the CSV corresponds with the OBLA intensity and could be a valuable index to plan a training schedule for physically disabled swimmers.  相似文献   
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