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81.
No abstract available for this article.  相似文献   
82.
Abstract

Inadequate protein intake contributes to poor nutritional status, reduced muscle mass, strength and function, and increased mortality. Evaluating differences in protein intake and related health indicators among racial/ethnic groups enables the development of targeted interventions. This study’s purpose was to determine differences in protein intake, nutritional status, and muscle strength/function among 273 older African, European, and Hispanic Americans. Protein intake, nutritional status, grip strength, timed-up-and-go (TUG), and chair stand assessments were conducted. Protein intake was significantly greater among Hispanic Americans (0.96?g/kg body weight) followed by European Americans (0.83?g/kg body weight), and African Americans (0.64?g/kg body weight). Intakes by all groups were below recommendations. Low nutritional status, grip strength, chair rise, and TUG scores were observed in African Americans and European American females and were consistent with lower protein intakes. Results show significant differences among the groups and the need for interventions to improve diet and physical health.  相似文献   
83.
羧甲基大豆多糖性能研究   总被引:3,自引:0,他引:3  
用氯乙酸作为羧甲基化试剂合成了羧甲基大豆多糖,测定了羧甲基大豆多糖,褐藻胶,褐藻胶-羧甲基大豆多糖合金膜的机构强度,溶解性,并对其肠溶性,抑菌性也作了探讨,实验表明:羧甲基大豆多糖可改进褐藻胶膜的柔韧性和抗冲击强度,与褐藻胶一样具有肠溶性,并对蜡样芽孢杆菌和枯草杆菌生长繁殖有抑制作用。  相似文献   
84.
Most published studies on the role of muscle strength in the maintenance of bone mineral density (BMD) focused on the relationship between specific muscle groups and adjacent bones, mostly in young and premenopausal women. This study examined the influence of grip strength on BMD of the metacarpal index in postmenopausal Japanese women. Subjects included 1168 postmenopausal women aged 40–70 years. BMD measurement was done with computed X-ray densitometry (CXD) by analyzing X-ray films of the right second metacarpal index. Grip strength was measured in both the dominant and nondominant hands using a squeeze dynamometer. Grip strength (r = 0.2474; P= 0.0001) and age (r =−0.5443; P= 0.0001) significantly correlated positively and negatively, respectively, with BMD. Physical activity (r = 0.1318; P= 0.0001) also correlated positively with BMD. Breastfeeding (r =−0.1658; P= 0.0001), however, correlated negatively with BMD. Subjects with a history of regular physical activity had higher grip strengths and BMD, than those with no physical activity. Adjustment for age, physical activity, calcium intake, BMI, breastfeeding, testing site, and menopausal type indicated a significant (P for trend = 0.0013) positive association of grip strength with BMD. Subjects with stronger grip strengths had a decreased risk for low BMD. Received: 24 February 1998 / Accepted: 7 August 1998  相似文献   
85.
The ability to rise from a chair is an important task of daily living that is difficult for many elderly individuals to perform, and is particularly challenging when performed quickly. It is important to understand what factors limit performance of the task in older people, so that effective remedial approaches can be developed. In this study, we quantified lower-extremity muscle strength and chair-rise biomechanics in 12 young and 26 healthy elderly women during chair rise at normal and fast speeds without use of the hands. We found that hip and knee extensor torques, vertical and horizontal momentum, and vertical and horizontal ground reaction forces increased in the same way with speed for all subjects. All subjects increased their speed from normal to fast trials, but the young subjects were able to rise more quickly in the fast trials. In the normal speed trials, elderly subjects generated more trunk flexion and horizontal momentum while still in contact with the chair. Muscle activity patterns were similar for all subjects except that the elderly activated the ankle extensors earlier than the young. Although the elderly subjects were much weaker relative to body weight than the young subjects (48.5±14.1%), they were able to generate sufficient torques to perform the task. However, age-related differences suggest that chair-rise biomechanics were affected by the reduction in muscle strength, and that strength training regimens, particularly for the hip musculature, may be important to maintain chair-rise ability in the elderly.  相似文献   
86.
膝关节前交叉韧带损伤及重建后肌肉力量变化的研究   总被引:6,自引:0,他引:6  
对ACL陈旧性损伤、急性损伤、手术重建以及未损伤对象四个样本组 ,在等长条件下膝关节肌肉屈伸、旋内 ,旋外、内收和外展的力量情况进行了对比测试。共记录了 5 4个研究对象的 80组测试结果。结果表明各样本组肌肉力量比值在不同方向上存在显著性差异。该结果可能有助于解释ACL损伤及重建后神经肌肉系统的补偿机制 ,并提示通过选择性地训练某些肌肉可达到有效的康复效果。  相似文献   
87.
Estrogen deficiency causes reduction of bone mass and abnormal bone microarchitecture, consequently reducing bone strength. Human parathyroid hormone (hPTH) (1-34) increases bone mass and strength. To clarify the factors that determine the recovery of bone strength in the lumbar vertebrae of ovariectomized rats by intermittent hPTH administration, we analyzed the relationship between skeletal measurements and bone strength. Human PTH (1-34) administration resulted in recovery of cortical bone mineral content (BMC) and cortical bone area to sham the levels, but in resulted in a less pronounced recovery of trabecular BMC and no increase in the total cross-sectional area of the vertebral body. Of the three-dimensional (3D) trabecular bone parameters, hPTH (1-34) increased trabecular thickness (Tb.Th). The cortical shell area of L4, determined by histomorphometry, was also increased. In hPTH-treated rats, the only determinant of the compressive load of L5 was the cortical shell BMC, in the early recovery period (days 42–84). Our data suggest that increased cortical bone mass contributes more than trabecular bone mass and structure to the recovery of bone strength in response to hPTH therapy in the rat lumbar vertebral body after ovariectomy.  相似文献   
88.
The aim of the study was to measure pelvic floor muscle function in continent and incontinent nulliparous pregnant women. The study group consisted of 103 nulliparous pregnant women at 20 weeks of pregnancy. Women reporting urinary incontinence once per week or more during the previous month were classified as incontinent. Function was measured by vaginal squeeze pressure (muscle strength) and increment in thickness of the superficial pelvic floor muscles (urogenital diaphragm) assessed by perineal ultrasound. Seventy-one women were classified as continent and 32 women as incontinent. Continent women had statistically significantly higher maximal vaginal squeeze pressure and increment in muscle thickness when compared with incontinent women. There was a strong correlation between measurements of vaginal squeeze pressure and perineal ultrasound measurements of increment in muscle thickness. This study demonstrates statistically significant differences in pelvic floor muscle function measured by strength and thickness in continent compared with incontinent nulliparous pregnant women. Editorial Comment: This study evaluated pelvic floor muscle function in 103 nulliparous continent and incontinent women at 18–20 weeks gestation. Pelvic floor muscle strength was assessed by measuring vaginal squeeze pressure, and thickness of the urogenital diaphragm during both relaxation and contraction was measured using perineal ultrasound. The authors found a statistically significant higher vaginal squeeze pressure and higher mean increment in muscle thickness in the continent compared with incontinent group as well as a strong correlation between pelvic floor muscle strength and increment in thickness. Although describing several benefits of ultrasonography in assessing pelvic floor muscles, the authors did acknowledge the difficulty in identifying and measuring these muscles, and the learning curve involved with perineal ultrasound. Another limitation was the subjective classification of continence status based on self-reported symptoms. The implication of low pelvic floor muscle strength and thickness as risk factors for the development of urinary incontinence is beyond the scope of this study.  相似文献   
89.
This research was designed to study the effects of low-power helium–neon (He–Ne) laser irradiation on random skin flap survival in rat. Fifty 50 male rats were randomly divided into five groups. On the dorsum of each rat, one full thickness random skin flap which contained no specific vessel was elevated. Groups 1 to 4 were exposed to different models of a low-power He–Ne laser. Group 5 rats received no laser treatment and were considered as the control group. The energy density of the He–Ne laser used was 0.2 J/cm2. Immediately after surgery and at day 7, the surface area of all flaps was determined. Histological and tensiometrical studies on the surviving part of the flaps were also performed. The data obtained were analyzed by ANOVA. The results showed a significant difference in the surface area of survival parts of flaps and density of blood vessels on day 7 between group 3 rats and the other groups (P=0.0188, P=0.0455). Low-power He–Ne laser irradiation of flaps without recognized blood vessels in rats, reduced vasospasm, produced vasodilation, and caused a significant increase in the surviving surface area.Presented at the 14th World Congress of the International Society for Laser Surgery and Medicine, India, 27–30th August, 2001  相似文献   
90.
目的 评价不同表面设计的腰椎后路椎间融合器的抗拔出性能。方法  1 2具男性青壮年新鲜尸体的L3、4节段 ,分 3组模拟后路双侧植入螺纹表面柱状椎间融合器 (Interfix) ,锯齿表面方形融合器 (Prospace)和光滑表面方形融合器 (Syncage)。每组共 4个标本 8枚融合器。在生物力学实验机上通过传感器测定各个融合器的最大拔出力并得出拔出曲线。比较试验结果并进行生物力学评价。结果 三种融合器之间的最大拔出强度分别为 6 95± 1 75N (Interfix) ;2 5 8± 6 5N (Prospace) ;1 30± 34N(Syncage)。三者之间均有统计学差异 (P <0 0 5 )。同时三种融合器的拔出曲线具有不同特征 ,其拔出斜率分别为 1 95 6± 75N/mm、 5 0 4± 2 4N/mm、 1 6 3± 7 4N/mm (按Interfix ,Prospace和Syncage的顺序 ) ,三者之间差异显著 (P <0 0 5 )。 结论 在用于测试的 3种融合器中 ,表面带螺纹的Interfix拔出强度最大 ,表面带连续锯齿的Prospace次之 ,表面光滑的Syncage最差。各融合器的拔出性能与其表面设计有关系  相似文献   
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