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61.
Summary The effects on heart rate, oxygen uptake, and pulmonary ventilation of muscular exercises, including both dynamic contractions, either simple or combined, were studied in 4 male subjects, aged 21 to 23 years. The dynamic work consisted in cycling on an ergometric bicycle at three power levels: 40, 80, and 100 W. The static work consisted in pushing against, pulling and holding with the arms a 6, 9, 12, or 18 kg load. The physiological effects are expressed as cardiac cost (HR), oxygen cost (VO2) and ventilation cost (V). The physiological cost of the combined work increases according to the cycling power and to the isometric load developed. A statistical analysis shows that the costs of combined work are not different from the sum of the costs of the static and dynamic contractions measured separately. Thus, the physiological responses to the combinations investigated are of an additive type. 相似文献
62.
Y. Epstein J. Rosenblum R. Burstein M. N. Sawka 《European journal of applied physiology》1988,57(2):243-247
Summary The present study was undertaken to examine the energy cost of prolonged walking while carrying a backpack load. Six trained subjects were tested while walking for 120 min on a treadmill at a speed of 1.25 m · s–1 and 5% elevation with a well fitted backpack load of 25 and 40 kg alternately. Carrying 40 kg elicited a significantly higher (p<0.01) enery cost than 25 kg. Furthermore, whereas carrying 25 kg resulted in a constant energy cost, 40 kg yielded a highly significant (p<0.05) increase in energy cost over time. The study implies that increase in load causes physical fatigue, once work intensity is higher than 50% maximal work capacity. This is probably due to altered locomotion biomechanics which in turn lead to the increase in energy cost. Finally, the prediction model which estimates energy cost while carrying loads should be used with some caution when applied to heavy loads and long duration of exercise, since it might underestimate the acutal enery cost. 相似文献
63.
The energetics of middle-distance running 总被引:3,自引:0,他引:3
J. R. Lacour S. Padilla-Magunacelaya J. C. Barthélémy D. Dormois 《European journal of applied physiology》1990,60(1):38-43
Summary In order to assess the relative contribution of aerobic processes to running velocity (v), 27 male athletes were selected on the basis of their middle-distance performances over 800, 1500, 3000 or 5000 m, during the 1987 track season. To be selected for study, the average running velocity
corresponding to their performances had to be superior to 90% of the best French
of the season. Maximum O2 consumption
and energy cost of running (C) had been measured within the 2 months preceding the track season, which, together with oxygen consumption at rest
allowed us to calculate the maximalv that could be sustained under aerobic conditions:
. The treadmill runningv corresponding to a blood lactate of 4 mmol·–1 (v
la4), was also calculated. In the whole group, C was significantly related to height (r=–0.43;P<0.03). Neither C nor
(with, in this case, the exception of the 3000 m athletes) were correlated to
. On the other hand,v
a max was significantly correlated to
over distances longer than 800 m. These
were also correlated tov
la4. Howeverv
la4 occurred at 87.5% SD 3.3% ofv
a max, this relationship was interpreted as being an expression of the correlation betweenv
a max and
. Calculation ofv
a max provided a useful means of analysing the performances. At the level of achievement studied,
sustained over 3000 m corresponded tov
a max. The shape of the relationship ofv/v
a max as a function of the duration of the event raised the question of a possible change in C as a function of v during middle-distance running competitions. 相似文献
64.
This study is an extended follow-up for 24 months of a 12-week trial to study the long-term clinical efficacy of low-dose inhaled budesonide (BUD) once or twice daily in children with mild asthma. A total of 122 children (mean age 9.7 years, girls/boys; 42/80) with mild asthma (FEV1 103.7% of predicted, reversibility in FEV1 3.5%, and fall in FEV1 after exercise 12.2%), not previously treated with inhaled steroids, were included in a double-blind, randomized, parallel-group study. The children were treated with inhaled BUD 100 or 200 microg administered via Turbuhaler once daily in the morning, 100 microg twice daily, or placebo for 27 months. Exercise and methacholine challenges were performed at 3-month intervals the first year and at 6-month intervals the second year, in a total of seven visits. A significant dose-response effect favoring BUD 200 microg daily (vs 100 microg daily) was found when comparing changes in FEV1, FEF25%, and FEV50%; the fall in FEV1 after an exercise test; and the effect on blood eosinophils. Bronchial hyperreactivity to methacholine decreased significantly on three visits in patients treated with BUD 200 microg daily compared to placebo. Growth rate was not significantly affected except in children aged 7-11 years at baseline after 12 months of treatment. In conclusion, 100 or 200 microg daily of inhaled BUD for 27 months is safe and effective in protecting against exercise-induced asthma and achieving nearly normal lung function. Baseline lung function was not significantly affected in this group of children with mild asthma. 相似文献
65.
Predictive value of early HCV RNA quantitation for sustained response in nonresponders receiving daily interferon and ribavirin therapy 总被引:2,自引:0,他引:2
Trimoulet P de Lédinghen V Foucher J Castéra L Fleury H Couzigou P 《Journal of medical virology》2004,72(1):46-51
The prognostic value of early hepatitis C virus (HCV)-RNA load was evaluated among nonresponder patients to previous interferon (IFN) therapy treated with daily IFN and ribavirin. One hundred-six nonresponders (83 men), mean age 44.8 +/- 11 years, were treated with IFN-alpha 2b 3 MU/day for 24 weeks, followed by 3 MU x 3/week for 24 weeks plus ribavirin 1-1.2 g/day for 48 weeks. HCV RNA was quantified by Versant HCV RNA 3.0 assay (Bayer). The predictive values of the baseline and the change in viral load at week 1, 4, and 12 for sustained virological responses were analyzed using receiver operating characteristic (ROC) curves, as well as predictive values of >2 log(10) drop from baseline by weeks 1, 4, and 12 in combination with undetectable HCV RNA for sustained virological response. Thirty-two patients (30.2%) were sustained virological responders. The highest area under the curve was obtained at week 4. The unquantifiable HCV RNA level, in combination with at least a 2 log(10) drop in viral load by week 4 and week 12, had a negative predictive value of 96% and 97%, respectively. Nonresponse can be predicted as early as week 4 or week 12 in nonresponders treated with daily IFN and ribavirin. 相似文献
66.
目的探讨2668例急诊病房住院患者的临床病例特点,为急诊医护工作提供参考依据。方法选取2015年1月至2018年6月于宣武医院急诊科病房住院的2668例患者,回顾性地采集研究数据,包括性别、年龄、共病受累系统、住院费用、住院时间、住院前及出院前自理生活能力评分。结果1)男性患者入院平均年龄小于女性[(67.2±17.1)岁vs(70.7±17.2)岁](P<0.01)。2)2408例(90.25%)入院患者罹患3种以上共病,共病受累系统主要为呼吸、循环、内分泌。3)患者入院前生活能力评分显著低于出院前生活能力评分(69.42±25.09 vs 78.12±26.13)(P<0.001)。4)Barthel评分与住院时间、住院费用、白蛋白减低、贫血呈负相关。结论急诊病房病种复杂,涉及多学科多专业,病情危重多变,应在临床诊治和护理过程中给予综合、全面的评估,提高患者的治愈率。 相似文献
67.
目的探讨阿尔茨海默氏病(AD)和帕金森氏病(PD)对老年人认知功能及日常生活能力的影响。方法对2000~2003年就诊于我院的53例AD、68例PD和60例正常人应用简易智力量表(MMSE)和日常生活能力量表(ADL)进行分析。结果AD组与对照组相比MMSE总分及各因子分、ADL总分及各单项分均有显著性差异(P<0.01):PD组与对照组相比除MMSE的记忆力和语言因子分以及ADL第13项目(打电话)外,其余均有显著性差异(P<0.05):AD组与PD组相比除ADL第7项(穿衣)外均有显著性差异(P<0.05)。结论AD和PD对老年人的认知功能和日常生活能力均有显著的影响,两者相比,AD对老年人的影响更严重、更广泛。 相似文献
68.
Both immunoglobulin E (IgE)-mediated food allergy and food intolerance can lead to many changes in personal behaviour and health care resource use which have important economic consequences. These costs will impact directly, indirectly and intangibly on both individuals and society in general. It is important to measure the cost of illness (COI) of food allergy as a first step in developing and evaluating measures to reduce and control the burden of illness. This paper outlines a framework for assessing COI of food allergy from different viewpoints. It offers a structure for identifying the different cost impacts on allergic and nonallergic consumers, food producers and society as a whole, and for scoping, measurement and valuation of relevant costs. Within this structure, the existing literature is reviewed. This review illustrates the lack of information and clear methodology for assessing costs of food allergy. The paper concludes that there is a need for a more structured research programme to generate data essential for future evaluations of procedures and technologies for the diagnosis, treatment and management of food allergy. 相似文献
69.
A. Belli J. R. Lacour P. V. Komi R. Candau C. Denis 《European journal of applied physiology》1995,70(6):510-517
The present study was designed to study intra-individual step variability measured both on vertical displacement of the body (Z) and on step time (t) parameters by means of a kinematic arm and during treadmill running. A group of 17 subjects ran successively at 60%, 80%, 100% and 140% of their maximal aerobic velocity (v
amax). The total number of steps analysed was 6116. The absolute Z step variability (Z) ranged between 5 mm and 21 mm while the absolute t variability (t) ranged between 6 ms and 40 ms. Step variabilities were due to step asymmetry (from 38.5% to 48.5% of the step variability) and to stride variability. For submaximal velocities (60%, 80%, and 100%v
amax) both t and Z were independent of velocity or body dimensions whereas differences between subjects were significant (P < 0.01) for Z. On the other hand, variabilities were significantly increased when velocity was changed from submaximal to the 140%v
amax level. Furthermore, at submaximal levels Z was linked to the subject's energy cost of running (P < 0.05). Therefore, the intra-individual step variability should not be neglected in future studies on mechanical efficiency of running and it is suggested that, to obtain a good accuracy (better than 1%,P < 0.05) on mean value and variability of the mechanical parameters, measurements should be performed on at least 32–64 consecutive steps, which corresponds to about 15 to 20 s of running. 相似文献
70.
Sheldon C. Siegel M.D. Roger M. Katz M.D. Gary S. Rachelefsky M.D. Milan L. Brandon M.D. Lowell A. Borgen Ph.D. 《The Journal of allergy and clinical immunology》1985,75(6):698-705
Procaterol hydrochloride, a potent beta 2-adrenergic bronchodilator developed in Japan, was evaluated in a double-blind, placebo-controlled study for efficacy and safety in 45 patients (ages 18 to 55 yr) with chronic documented reversible airway disease. After a 1-week placebo washout period, patients were administered either 0.05 mg or 0.10 mg of procaterol or placebo twice daily for 2 wk. Spirometric determinations, vital signs, and ECGs were obtained at 1/2, 1, 2, 4, 6, and 8 hr after the first dose and at the same time intervals after 1 and 2 wk of treatment. Patients recorded on a daily basis peak flow rates, asthma symptoms, need for supplemental aerosol, concurrent medications, and side effects. Spirometry results indicated significant improvement in pulmonary function with both doses of procaterol compared with placebo (P less than 0.05). The larger dose was generally more effective. Bronchodilatation was evident 1/2 hr after dosing and peaked at 2 hr. At 8 hr after 0.10 mg of procaterol, FEV1 was still above predose values. Daily peak flow rates were significantly higher with 0.10 mg than with 0.05 mg (P less than 0.05) and placebo (P less than 0.001). Tremor and nervousness were the most frequent side effects. They occurred in a dose-related frequency, were mild and transient, and occurred early in treatment. No significant drug-related changes were noted in ECGs, heart rate, blood pressure, or clinical laboratory data. Procaterol was found to be an effective, well-tolerated oral bronchodilator with a long duration of action, especially at 0.10 mg twice daily. 相似文献