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71.
Effects of Clodronate on Cortical and Trabecular Bone in Ovariectomized Rats on a Low Calcium Diet 总被引:5,自引:0,他引:5
T. S. Kaastad O. Reikerås J. E. Madsen S. Narum J. H. Strømme K. J. Obrant L. Nordsletten 《Calcified tissue international》1997,61(2):158-164
The aim of this study was to evaluate the contribution of a low calcium diet to the cortical and trabecular osteoporosis
seen in ovariectomized rats after 7 weeks on a low calcium diet and to investigate the effects of the bisphosphonate clodronate
on this development of osteoporosis. Thirty-six mature, female Wistar rats were randomized into four groups: Ovx−B (bisphosphonate)
and Ovx−C (control) were ovariectomized, and Sham−Ca (low calcium) and Sham+Ca (normal calcium) were sham operated. The first
three groups were fed a low calcium diet (0.01%) and Sham+Ca normal rat chow (Ca 1.1%). The Ovx−B received 10 mg/kg s.c. clodronate
daily for nine weeks, and Ovx−C, Sham−Ca, and Sham+Ca received the same volumes of saline. Bone mineral turnover measured
as 85Sr-uptake was increased in all low calcium groups compared to Sham+Ca. The Sham+Ca femora had higher dry weight and ash weight
than the other groups, and Ovx−C had higher dry weight compared with Ovx−B and Sham−Ca. Calcium content was lower in both
Ovx groups compared to both Sham groups. Magnesium was lower in all groups compared to Sham+Ca and higher in Ovx−B compared
with Ovx−C. In the femoral shaft, Sham+Ca had significantly higher ultimate bending moment, energy absorption, and deflection
compared to the other three groups. Ultimate bending moment was higher in Sham−Ca than in Ovx−C. Stiffness was increased in
both Sham+Ca and Ovx−B compared to Ovx−C. The maximum stress in the femoral midshaft was higher in Sham+Ca than in the other
groups, and higher in Ovx−B than in Ovx−C. Histomorphometry showed increased medullary area in all low calcium groups compared
to Sham+Ca and larger cortical area in Sham+Ca and Ovx−B compared to Ovx−C. Compared to Sham+Ca the trabecular bone volume
was decreased to 30% in Sham−Ca and to 9% in Ovx−C, but was unchanged in Ovx−B. The low calcium diet generally increased bone
mineral turnover and reduced the tibial bone volume. Femoral changes led to a reduction of cortical fracture strength and
maximal stress. Ovariectomy in addition to a low calcium diet reduced femoral strength even more. Daily injections of clodronate
to ovariectomized rats on a low calcium diet increased femoral shaft stiffness and maximum stress, and clodronate preserved
both trabecular and cortical tibial bone volume completely.
Received: 11 June 1996 / Accepted: 5 March 1997 相似文献
72.
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
73.
冷冻异体手指复合组织移植后的骨关节病变观察 总被引:6,自引:0,他引:6
目的 研究自体Mu甲皮瓣游离移植包裹冷冻异体手指骨-关节-肌腱-腱鞘复合组织再造Mu,手指后,异体指骨关节病变发生的特点。方法 应用X线片和病理活检方法,对16例植入11个月-15年6个月,平均4年5个月的病变异体骨关节进行观察和评价。结果 异体骨关节病变过程可分早期(<2年),中期(2-10年)和晚期(>10年)。X线摄片分别显示软骨下骨虫蛀样缺损,骨关节吸收脱位和毁损。所有的病变骨关节中未见炎性细胞浸润,异体肌腱内见肌腱样细胞生长。结论 异体指骨关节病变严重程度与病程有关,其表现类似于失神经关节病变(Charcot关节病)。异体肌腱可长期存活。 相似文献
74.
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
75.
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
76.
目的探讨采用吻合指固有神经背侧支的邻指皮瓣修复手指远端掌侧软组织缺损的疗效. 方法 1996年10月~2004年6月,25例(32指)伴肌腱或骨组织外露的手指远端掌侧软组织缺损患者,其中男18例,女7例,年龄13~45岁.切割伤6例,冲压伤8例,机器绞伤11例.损伤部位:拇指2例,食指8例,中指5例,环指3例,小指2例,食、中指2例,中、环指2例,食、中、环、小指1例.缺损范围:1.5 cm×1.0 cm~4.0 cm×2.1 cm.损伤至就诊时间30 min~48 h.急诊行清创,采用带蒂邻指皮瓣修复,术中同时将指固有神经的背侧支与指神经残端吻合重建皮瓣感觉,术后3周断蒂.供区中厚皮片游离植皮. 结果术后皮瓣及供区均成活,创面Ⅰ期愈合.获随访6~26个月,手指指腹饱满,色泽正常,感觉恢复,两点辨别觉为5~8 mm,均无功能障碍. 结论采用吻合指固有神经背侧支邻指皮瓣修复手指远端掌侧软组织缺损不仅能修复缺损皮肤,且能重建皮瓣感觉,术式操作简便. 相似文献
77.
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
78.
79.
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
80.
本研究评价了喷砂、氢氟酸(HF)、氢氟酸处理后涂KH-570乙醇液等方法时国产GD光固化复合树脂以及进口VIVADENT复合树脂的修补效果.结果表明:9.6%HF处理国产树脂、喷砂处理进口树脂均获得最大的修补强度,HF KH-570处理方法虽为每种材料中之最小者,但与其它修补方法间无显著性差异. 相似文献