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81.
目的探讨旋转强恒磁场(RCSMF)对SD大鼠的骨骼生长发育及相关激素的影响,为RCSMF促进人体增高的临床应用奠定基础。方法取25日龄的SD大鼠置RCSMF下,1.5h/d。每5天取血检测大鼠生长激素(GH)、类胰岛素生长因子(IGF-Ⅰ)、雌激素(E2)等与骨骼发育相关的激素,同时测量每组大鼠的身长、体重和尾长,并用骨形态计量学方法研究RCSMF对大鼠骨组织形态学和动态学参数的影响。结果RCSMF处理后大鼠的身长[实验组(25.28±0.41)cm。对照组(24.05±0.35)cm;P〈0.01]、体重[实验组(445.90±16.88)g,对照组(382.22±12.78)g;P〈0.01]、胫骨长[实验组(3.89±0.13)cm,对照组(3.66±0.10)cm;P〈0.01]和股骨长[实验组(3.65±0.08)cm,对照组(3.51±0.06)cm;P〈0.01],上述多项参数以及骨骺板等相关形态计量学数据实验组明显高于对照组。回归分析身长与相关激素的关系显示:大鼠身长与GH、IGF—I和E2有显著相关性。结论RCSMF有促进骨骼生长发育的作用,其作用机理是通过刺激与骨骼生长发育相关激素的生成、释放,并影响软骨细胞的增殖功能来完成的。 相似文献
82.
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
83.
运动训练对雄性大鼠垂体─性腺轴功能的影响 总被引:3,自引:2,他引:1
本研究通过使用自己制造的大鼠流动水游泳池,对雄性大鼠进行了6周递增负荷的游泳训练,以此来探讨运动训练对大鼠垂体-性腺轴功能的影响,结果显示:与安静对照大鼠相比,训练大鼠的一般状态较差,血清睾酮水平显著降低(P<0.05),血清睾酮/皮质酮比值平均降低了30%以上;而血清LH和FSH水平未见明显变化。通过对大鼠睾丸组织LH/CG受体的测定,显示运动训练虽未引起其最大结合量的改变,却能使其解离常数显著升高(P<0.05)。提示此种训练可能通过降低睾丸LH/CG受体对垂体分泌LH的亲和力,从而影响睾酮的合成。 相似文献
84.
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
85.
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
86.
OBJECTIVE: We aimed to gather information from the members of the Association of Coloproctology of Great Britain and Ireland (ACPGBI) to assess trends in the current practice of laparoscopic colorectal surgery. METHODS: A postal questionnaire survey of the members of ACPGBI. RESULTS: The response rate was 37% (200/540). Only 45 surgeons currently perform laparoscopic colorectal work in Great Britain and Ireland mainly right hemicolectomy and laparoscopic stoma formation, of these about one third practiced laparoscopy for benign colorectal conditions only. The majority (68%) of surgeons had enough resources at their place of work, but further training seemed to be a major issue. Nearly 22% of surgeons had not had any formal training. Only 50% of surgeons trained their specialist registrars. The incidence of conversion rate was not different for benign or malignant conditions and also did not appear to be related to the duration of experience. Only four surgeons had noted port a site recurrence during the past 10 years. Seventy-five percent (150/200) felt that laparoscopic colorectal work could be carried out safely in a District General Hospital. CONCLUSION: Laparoscopic colorectal surgery was being performed by a small minority of members of the ACPGBI although more surgeons had started to work in this field in recent years. The main areas of concern appeared to be a wide variation in the range of experience as indicated by the number of operations performed and limited formal training for consultants. 相似文献
87.
Steven C. Hayes 《Clinical psychology》2002,9(4):410-415
The combination of a stage model of psychotherapy and treatment manualization has been a major step forward in treatment development and efficacy testing, but not in dissemination. I argue that the technological model of treatment development makes research on the practical application of these technologies difficult. If we continue on our present course, research on dissemination will be uncommon, expensive, and largely irrelevant to the practical issues that need to be faced. It makes more sense to proceed directly to dissemination research. Alternative methods, including manipulated training designs, will permit this, but these fundamentally challenge the implicit assumptions of the stage model. 相似文献
88.
89.
Activities of creatine kinase isoenzymes in single skeletal muscle fibres of trained and untrained rats 总被引:1,自引:0,他引:1
Katsumasa Yamashita Toshitada Yoshioka 《Pflügers Archiv : European journal of physiology》1992,421(2-3):270-273
Biochemical changes in the creatine kinase isoenzyme compositions in single muscle fibres of different types in rats were induced by endurance running training. Single muscle fibres were dissected from the soleus and extensor digitorum longus muscles of Wistarstrain male rats trained on a motor-driven treadmill for 16 weeks. Each fibre was typed histochemically (SO, slow-twitch oxidative; FOG, fast-twitch oxidative glycolytic; FG, fast-twitch glycolytic), and the activities of total creatine kinase and its four isoenzymes (CK-MM, -MB,-BB, and mitochondrial creatine kinase) were measured. The endurance training did not affect the total creatine kinase activity, but resulted in significantly increased activities of CK-MB and CK-BB in SO and FOG fibres, and the mitochondrial enzyme activity in FOG and FG fibres. Endurance training induced biochemical changes in the isoenzyme compositions, specifically in FOG fibres. These results suggest that changes in creatine kinase isoenzymes with endurance training reflect changes in the energy metabolism in the different muscle fibres, supporting the hypothesis that the different isoenzymes play different roles in energy transduction. 相似文献
90.
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