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51.
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
52.
The aim of this investigation was to determine whether age-related changes in the dynamics of muscle activation were, in part, responsible for longer reaction times (RT) in the elderly. A group of 12 young (mean age, 20.6 years) and 12 elderly (mean age, 64.3 years) women performed a series of ballistic forearm supination movements in response to an auditory stimulus while using a simple reaction time test. Surface electromyographic waveforms from biceps brachii (agonist) and pronator teres (antagonist) muscles were recorded, together with the angle-time curves representing the motion of the forearm, on to an IBM compatible microcomputer. The results showed that an age-related increase (P<0.05) in motor reaction time (MRT) contributed to longer RT in the elderly. In addition, the longer (P<0.05) MRTs in the elderly were associated with a significantly slower rate (P<0.05) of biceps brachii muscle activation and a significantly increased proportion (P<0.05) of the initial biceps brachii muscle burst required to initiate the movement. This data suggested that an important part of the slowing of motor behaviour, commonly observed with increasing age, may be due to either decreases in the ability of aged skeletal muscle to rapidly generate tension or to a reduction in motor drive. 相似文献
53.
The purpose of this cross-sectional study was to evaluate bone mass in female athletes participating in an impact loading
sport (volleyball), and especially to investigate whether any changes in bone mass might be related to the type and magnitude
of weightbearing loading and muscle strength. The volleyball group consisted of 13 first division players (age 20.9 ± 3.7
years) training for about 8 hours/week, and the reference group consisted of 13 nonactive females (age 25.0 ± 2.4 years) not
participating in any kind of regular or organized sport activity. The groups were matched according to weight and height.
Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter,
the whole femur, and humerus using dual-energy-X-ray absorptiometry. Isokinetic concentric peak torque of the quadricep and
hamstring muscles was measured using an isokinetic dynamometer. Compared with the controls, the volleyball players had a significantly
(P < 0.05–0.01) higher BMD of the total body (6.1%), lumbar spine (13.2%), femoral neck (15.8%), Ward's triangle (17.9%), trochanter
(18.8%), nondominant femur (8.2%), and humerus (dominant 9.5%, nondominant 10.0%), but not of the head and the dominant whole
femur. The dominant humerus showed significantly higher BMD than the nondominant humerus in both the volleyball and nonactive
group (P < 0.05). There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group,
muscle strength in the quadriceps, and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip
sites) and also to distant sites (humerus). However, in the volleyball group there were no correlations between muscle strength
and BMD of the adjacent bones, but quadricep strength correlated to BMD of the humerus. These results clearly show that young
female volleyball players have a high bone mass. The demonstrated high bone mass seems to be related to the type of loading
subjected to each BMD site. Muscle strength of the thigh seems to have little impact on BMD in female volleyball players.
Received: 18 June 1996 / Accepted: 31 October 1996 相似文献
54.
Predicted and Measured Muscle Forces after Recoveries of Differing Durations Following Fatigue in Functional Electrical Stimulation 总被引:2,自引:0,他引:2
Abstract: Using 31 P nuclear magnetic resonance (NMR) spectroscopy, the bioenergetics of paralyzed muscles activated by functional electrical stimulation (FES) were studied in vivo during fatigue and recovery on paraplegic subjects. During the activation phase of the muscle, the muscle force was also monitored. The phosphorus metabolites were found to vary systematically during fatigue and to recover slowly to their rest state values after cessation of FES. During fatigue, a good correlation was found between the decaying force and each of the profiles of phos-phocreatine, inorganic phosphorus, and intracellular pH. A musculotendon 5 element model was proposed for the activated muscle to predict its force generation capacity. A fatigue recovery function, based on the metabolic profiles, was introduced into the model. This model allowed us to predict the force expected to be developed as a function of the time after recovery of given time durations. Validation experimental measurements of force were carried out and included recurrent fatigue tests, both in the initially un-fatigued state and at various times in the postfatigue stage of the muscle. Comparison of the predicted and measured forces indicated satisfactory agreement of the results. The developed model of muscle dynamics should help to design a strategy for reducing muscle fatigue under FES. 相似文献
55.
Memory function in normal aging 总被引:4,自引:0,他引:4
Lars-Göran Nilsson 《Acta neurologica Scandinavica》2003,107(S179):7-13
Basic findings obtained on memory functions in normal aging are presented and discussed with respect to five separate but interacting memory systems. These systems are: episodic memory, semantic memory, short-term memory, perceptual representation system and procedural memory. All available evidence from cross-sectional research shows that there is a linear, decreasing memory performance as a function of age for episodic memory. Longitudinal studies suggest, however, that this age deficit may be an overestimation, by showing a relatively stable performance level up to middle age, followed by a sharp decline. Studies on semantic memory, short-term memory, perceptual representation system, and procedural memory show a relatively constant performance level across the adult life span, although some tasks used to assess short-term memory and procedural memory have revealed an age deficit. Disregarding the mixed results for these latter two memory systems, it can be concluded that episodic memory is unique in showing an age deficit. Episodic memory is also unique in the sense that it is the only memory system showing gender differences in performance throughout the adult life span with a significantly higher performance for women. 相似文献
56.
作者采用肌蒂移植术治疗胸腰段陈旧性脊髓损伤56例.脊髓功能恢复率提高至Franke 1个等级以上者占76.8%(43/56).本文讨论了肌蒂移植术对陈旧性脊髓损伤的适应证.安徽省宿州市骨伤科医院淮北煤矿基建局医院 相似文献
57.
细胞移植治疗心肌梗死的研究与展望 总被引:2,自引:0,他引:2
细胞移植是治疗心肌梗死的一种新策略,本文对目前应用于临床研究的骨骼肌卫星细胞移植及骨髓干细胞移植治疗心肌梗死的进展进行综述。上述两种细胞移植均具有来源丰富、无排斥反应的特点,而且通过研究观察表明,上述两种细胞移植后,心脏功能均能得到改善,故具有美好发展前景。但二者亦均具有不足之处和需要解决的问题,还需进一步研究与探索。 相似文献
58.
不同剂量普伐他汀治疗急性脑梗死的疗效和安全性研究 总被引:1,自引:0,他引:1
目的:探讨不同剂量普伐他汀在脑梗死急性期治疗的可行性、降脂疗效及安全性。方法:脑梗死急性期病人146例,随机分为3组,A组(50例)为对照组,B组(49例)每晚服普伐他汀10mg,C组(47例)每晚服普伐他汀20mg,观察30d。比较治疗前后血脂、神经功能缺损评分、生化指标等变化,并记录服药后不良反应。结果:各组总胆固醇(TC)、低密度脂蛋白(LDL-C)、超敏C-反应蛋白(hs-CRP)在治疗后都有所下降,C组下降最显著,B组次之,A组下降程度较小。A组TG治疗前后无明显变化,B组和C组TG治疗后有所下降,两组间无明显差别。脂蛋白(Lpa)在A组治疗后有下降,B组无明显变化,C组较前轻度升高。各组治疗前后神经功能缺损评分均有降低,但各组之间比较无明显差异(P〉0.05)。观察期间所有病人均能耐受普伐他汀,治疗前后肝、肾功能、肌酸激酶(CK)等无明显变化。结论:在脑梗死急性期应用普伐他汀(每日10~20mg)是安全可行的,且每日20mgTC、TG降低更显著,脑梗死急性期的病人应用普伐他汀后取得较好的降脂疗效,神经功能缺损评分的改善有待较长期观察。 相似文献
59.
目的评价选择性臂丛神经根切断治疗上肢痉挛性脑瘫的远期疗效。方法对1997年3月-2002年1月间施行选择性臂丛神经根切断术治疗上肢痉挛性脑瘫的患者,进行随访并对远期功能进行评价,采用Lazareg肌张力分级标准评定临床效果。结果16例17侧获得随访,随访时间为5.0~9.7年,平均8.6年。手术方式为选择性臂丛神经根全根切断10侧,部分切断2侧,高选择性分束切断5侧;其中切断神经根为颈63次,颈816次。术后远期疗效优3例,有效5例,无效8例9侧。结论选择性臂丛神经根切断治疗上肢痉挛性脑瘫远期大多数疗效下降和无效,但术前严格选择痉挛较局限的病例、术中进行高选择性臂丛神经根分束切断、术后坚持长期康复训练仍然能获得较好的疗效。 相似文献
60.
Nicholas Stephens Eric Marques Christopher Livingston 《CANADIAN JOURNAL OF PLASTIC SURGERY》2007,15(1):44-46
Anomalies of the flexor digitorum superficialis muscle are extremely uncommon and usually present as a painful mass or pseudotumour within the palm. Diagnosis may be difficult because many other soft tissue tumours (lipomas, ganglions, giant cell tumours and hamartomas) may present similarly. Magnetic resonance imaging helps to define the extent and characteristics of this anomalous muscle belly and to distinguish it from a soft tissue sarcoma, whereas plain radiographs are of little value. Three types of flexor digitorum superficialis muscle anomalies have been described, and treatment consists of subtotal or total surgical debulking of the mass if symptoms persist or if the diagnosis is in question. Most patients have complete resolution and full recovery. To date, 20 cases have been reported in the literature, usually involving the right small finger. In the present paper, the case of an anomalous flexor digitorum superficialis muscle in a 17-year-old male patient’s left index finger is reported. Symptoms were relieved following surgical debulking and hand-based occupational therapy. 相似文献