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51.
PICANO E.; MARRACCINI P.; Lattanzi F.; Levantesi D.; Masini M.; Vacche M.Dalle; DlSTANTE A.; 'ABBATE A. 《European heart journal》1987,8(1):38-44
Twenty-four patients with a history of effort angina, a positiveexercise stress test (EST) and coronary artery disease wereenrolled in the study; 12 patientshada positive dipyridamole-echocardiographytest (DET) and 12 had a negative DET. Each patient performeda total of 4 ESTs in the absence of therapy on two successivedays; for each test the rate-pressure product (RPP), an establishedindex of my ocardial oxygen demand, was measured at the onsetof ischaemia (ST depression >015mV) or at the peakof maximal exercise (if a repeated EST was negative). Taking into account the lowest of the 4 RPP values ( x 1/100)in each patient, there was no significant difference betweenDET-negatives and DET-positives (185.2±49.3 vs 157.4±32.4).Conversely, when considering the highest of the 4 RPP valuesin each patient, there was a significant difference betweenDET-negatives and DET-positives (280.3 ± 63.9 vs 183.3± 37.0; p < 0.01). Thus, DET may provide a clinically useful tool for assessingin the individual the organic ceiling of coronaryreserve, by eliminating the variability in coronary tone, whichmay affect EST reproducibility and the correct evaluation ofthe impairment of organic coronary reserve. 相似文献
52.
Effect of Psoas Training on Postmenopausal Lumbar Bone Loss: A 3-Year Follow-Up Study 总被引:4,自引:0,他引:4
M. A. Mayoux-Benhamou F. Bagheri C. Roux G. R. Auleley J. P. Rabourdin M. Revel 《Calcified tissue international》1997,60(4):348-353
The present study completed a previous randomized trial that demonstrated the protective effect of 1-year psoas training
on lumbar bone loss in postmenopausal women. Computerized tomography had been carried out at the beginning (CT1) and at the
end (CT2) of this trial. In the present study, 67 women having completed the first trial were asked to practice psoas exercises
(60 hip flexions in sitting position with a 5 kg weight on the knee) for 2 additional years with a third CT control at the
end of this period (CT3). The aim of this complementary study was to assess the compliance rate and long-term effect on bone
of daily psoas muscle training over a longer period. Twenty-one women performed this daily psoas training for 3 years from
CT1 to CT3, and 14 acted as controls during the same period. Fourteen women were controls during the first year (from CT1
to CT2) but practiced psoas training during the following 2 years (from CT2 to CT3). Four women were psoas trained during
the first year (from CT1 to CT2) and subsequently crossed over to the control group for the last 2 years. The compliance rate
was 42%, with an attendance rate of 88%. The lumbar bone loss was lower in the 21 women trained over the 3 years (−3.26 ±
28.45 mg/cm3) than in the 14 untrained women (−16.79 ± 8.51 mg/cm3) (P= 0.02). The bone loss was not significantly reduced between the two periods of the study in the 12 women having been controls
from CT1 to CT2 and having crossed over to the active training group from CT2 to CT3. Psoas training may be effective against
lumbar bone loss. We conclude that specific training may play a contributing role in the preventive strategy to avoid osteoporosis.
Received: 23 February 1996 / Accepted: 25 October 1996 相似文献
53.
P. M. TIIDUS S. ZAJCHOWSKI D. ENNS D. HOLDEN E. BOMBARDIER A. N. BELCASTRO 《Acta physiologica (Oxford, England)》2002,174(2):131-136
The effects of oestrogen administration on 1 h post‐exercise cardiac muscle myeloperoxidase (MPO) and calpain activities were determined in female rats. Rats were ovariectomized and implanted for 2 weeks with either oestrogen (25 mg 17‐oestradiol) or placebo pellets or left with ovaries intact. Rats were then run for 1 h at 21 m min–1, 12% grade, killed 1 h post‐exercise and cardiac muscle and blood samples were removed. Control animals from each group were killed without prior exercise. Serum oestrogen levels in the order of the highest to lowest were; ovariectomized oestrogen replaced rats > intact ovaries rats > ovariectomized placebo rats. Oestrogen induced significant (P < 0.05) elevations in cardiac MPO activity at rest and at 1 h post‐exercise in ovariectomized rats. No significant elevations in cardiac MPO activity were evident in placebo ovariectomized or normal ovary rats at rest or post‐exercise. Cardiac calpain activities were similar in all unexercised groups. Ovariectomized placebo and intact ovary rats had significantly (P < 0.05) elevated cardiac calpain activities 1 h post‐exercise while calpain activity was not significantly elevated in hearts from ovariectomized oestrogen rats. These results demonstrate that oestrogen supplementation in ovariectomized rats induces elevations in cardiac muscle MPO activities at rest and at 1 h post‐exercise. This is opposite to the effect of oestrogen in post‐exercise skeletal muscle and implies a greater neutrophil infiltration into cardiac muscle caused by oestrogen. This effect cannot be explained by changes in 1 h post‐exercise cardiac muscle calpain activity, the elevation of which was suppressed by oestrogen administration. Oestrogen influences cardiac calpain activity similarly to its effect in skeletal muscle. Thus, oestrogen administration to ovariectomized rats induces elevations in cardiac MPO activity while suppressing cardiac calpain activity. 相似文献
54.
目的:观察采用谷氨酰半胱氨酸合成酶抑制剂--丁胱亚磺酰亚胺(BSO)排空大鼠心肌谷胱甘肽(GSH)是否影响大鼠心肌组织GSH的稳态,以及是否对GSH代谢相关酶活性及mRNA表达产生影响.方法:采用长时间力竭运动、注射BSO排空GSH两种实验模型,比较对照组与注射BSO组SD大鼠心肌在静息状态和长时间力竭运动后GSH状态及其代谢变化.结果:注射BSO 8天后,大鼠心脏GSH含量分别为对照组?%,且GSH的下降伴随着氧化型谷胱甘肽(GSSG)的下降,GSH/GSSG的比值无显著变化.GSH排空导致GSH代谢酶活性发生适应性变化,注射BSO后心肌中谷胱甘肽过氧化物酶(GPX)活性与对照组相比显著下降(P < 0.001).注射BSO组与对照组相比,心肌谷氨酰转肽酶(GGT)活性显著增加(P < 0.05).注射BSO力竭组与注射BSO组相比,心肌GGT活性显著增加(P < 0.001),心肌注射BSO抑制γ-谷氨酰半胱酸合成酶(GCS)活性,注射BSO力竭组大鼠心肌GCS mRNA表达量高于注射BSO组,表明极度排空谷胱甘肽后,GCS mRNA表达量的增加可能是机体产生的应激反应. 相似文献
55.
This article highlights positive outcomes for a convenience sample of six women (49-64 years of age) with fibromyalgia syndrome (FMS) who participated in an exercise program over 5 years. This group showed improvement with various FMS symptoms,fitness, and psychosocial factors early in the program, then showed further improvement as a result of adding new exercises to the protocol during the fourth and fifth years. Data suggest that certain people with FMS can improve their functional capacity with exercise over time, and move to even higher levels of physical function while aging and coping with FMS. Practical advice is provided for rehabilitation nurses regarding exercise and FMS. 相似文献
56.
57.
本文观察了10名游泳运动员和10名实验室工作人员在递增负荷运动中心功能的变化及其与无氧阈的关系.结果为:(1)游泳队员的无氧阈值明显高于无训练的实验室工作人员;(2)运动中每搏量稳定时的强度与无氧阈强度是密切相关的;(3)运动至无氧阈强度以后,心输出量的增加主要靠心率的增加来维持;(4)无训练者在运动一开始就动用心力储备,增加心率和每搏量,而游泳队员则在运动至40W以后才开始增加心率和每搏量.这些结果表明,无氧阈与心功能具有很密切的关系,可用它来反映心功能的好坏. 相似文献
58.
目的评价人工全膝关节置换术后康复锻炼在临床中的价值。方法术前让患者进行患肢髂关节的屈伸、旋转、活动,踝关节背伸、跖屈活动,股四头肌等长等张收缩锻炼,以提高患肢肌力,增强术后关节稳定性。结果20例患者平均关节活动度由80度提高到105度,平均KSS评分由46分提高到88分,术后功能恢复到接近正常人,无1例发生并发症。结论以预防并发症为中心的早期锻炼及指导患者出院后的持续功能锻炼,是患者康复的必由途径。 相似文献
59.
NUGENT A. M.; McPARLAND J.; McENEANEY D. J.; STEELE I.; CAMPBELL N. P. S.; STANFORD C. F.; NICHOLLS D. P. 《European heart journal》1994,15(3):361-368
Cardiac output was measured in 11 patients undergoing routinecardiac catheterization using a carbon dioxide rebreathing techniqueand compared with cardiac output measured by direct Fick andthermodilution. The carbon dioxide rebreathing technique gaveconsistently lower values for cardiac output than the othertwo methods (mean difference 0·73, 95% CI 0·95to0·511. min1 with the direct Fick and0·72. 95% CI 1·19 to 0·261.min1 with thermodilution). The direct Fick and thermodilutionmethods gave similar results (mean dtfference 0·08,95% CI 0·32 to 0·16a. min1). Cardiacoutput was also measured in 10 healthy subjects at rest andduring two steady-state levels of exercise using the carbondioxide rebreathing technique. Measurements were made in triplicateon 3 separate days. The technique gave reproducible resultsbetween replicates at rest (coefficient of variation 91%) andbecame more reproducible on exercise (coefficients of variation56% and 54% respectively at each exercise level). There wasa good correlation between cardiac output and oxygen consumption(r=0·98 The carbon dioxide rebreathing technique is afeasible non-invasive way of measuring cardiac output. It tendsto underestimate cardiac output at rest but is reproducibleand becomes more so on exercise which is where it should beof most value. 相似文献
60.
Kawashima Yoshiaki Cui Fude Takeuchi Hirofumi Niwa Toshiyuki Hino Tomoaki Kiuchi Katsumi 《Pharmaceutical research》1995,12(7):1040-1044
Purpose. Poorly compressible crystals of acebutolol hydrochloride were agglomerated by the spherical crystallization technique with a two-solvent system to improve the compressibility for direct tabletting. The mechanism of improvements in static compression behaviors and tablettabilities of the spherically agglomerated crystals were investigated.
Methods. The improvement of static compression behaviors of the agglomerated crystals was determined by measuring the stress relaxations and elastic recoveries of compressed powder of original and agglomerated crystals. The improved tablettability of agglomerated crystals was evaluated by the pressure transmission ratio upon compression, the ejection pressure for releasing the tablet from the die and the tablet strength, i.e., tensile strength required for breaking.
Results. The higher relaxation pressure and the lower elastic recovery of the agglomerated crystals than of the original crystals were found. The pressure transmission ratio data showed that the friction pressures of the two crystals were similar during the compression period. The ejection pressure of the agglomerated crystals was lower than that of the original crystals. The tensile strength of the tablet of agglomerated crystals was greater than that of the original crystals.
Conclusions. The compressibility and tablettability of the spherically agglomerated crystals prepared by the spherical crystallization technique were much improved due to their increased plastic property and reduced adhesive property compared to the original crystals. 相似文献