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1.
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
2.
Incidence, nature, and causes of ice hockey injuries. A three-year prospective study of a Swedish elite ice hockey team 总被引:2,自引:0,他引:2
In this prospective study, we have investigated incidence of injuries of different severity, types of injury, and mechanisms of injury during ice hockey practice and games. One Swedish elite hockey team was closely observed during three seasons (1982 to 1985). There was a total number of 95 injuries and 29 facial lacerations. The majority of injuries were minor (73%) and only 8% were classified as major. Seventy-six percent of the injuries occurred during games and 24% during practice. The incidence of injury during practice was 1.4 per 1,000 player-practice hours and 78.4 per 1,000 player-game hours. In comparison with other sports, the incidence of injury during hockey practice is very low, while that during games is high. Eighty percent of the injuries were caused by trauma and 20% by overuse. The most common types of injury were contusions, strains, and sprains. Complete tear of the medial collateral ligament of the knee was the most common severe injury. Most injuries resulted from body contact, predominantly tackling (checking), and from puck or stick contact. A reduction of the number of minor and moderate injuries should be possible by stricter enforcement of the hockey rules, especially against stick violations, and more widespread use of visors. 相似文献
3.
S Gizurarson M Lorentzon T R?munddal F Waagstein L Bergfeldt E Omerovic 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(6):411-416
AIMS: Severe sustained bradycardia may cause acute and possibly chronic congestive heart failure (CHF). The aim of this study was to investigate acute and chronic effects of complete heart block (CHB) on cardiac function, morphology, and creatine (Cr) metabolism. METHODS AND RESULTS: CHB was induced in male Sprague-Dawley rats (approximately 250 g, n = 11) by means of electrocautery applied to the region of AV node and were compared with controls (n = 15). The rats were investigated at 1, 3, and 12 weeks after CHB induction with transthoracic echocardiography. Invasive haemodynamic assessment of left and right ventricular pressures was performed at 12 weeks. After the sacrifice, the hearts were freeze-clamped for analysis of myocardial Cr, and high energy phosphometabolites. The efficacy of operative procedure was 54%. The peri-operative mortality rate was 20%. Heart rate (HR) decreased by approximately 50% (P < 0.01) while stroke volume (SV) increased 2.5 times (P < 0.01) in the CHB rats. Cardiac index remained unchanged. The rats with CHB grew normally and were in no apparent distress. Filling pressures in left and right ventricles were normal. The CHB rats developed marked cardiomegaly with biventricular dilatation and eccentric left ventricular hypertrophy (P < 0.01). There was no change in the myocardial content of Cr and high energy phosphometabolites. CONCLUSION: Rats with CHB are compensating for reduction in HR with increased SV without haemodynamic and biochemical characteristics of CHF. This model may be useful to study the effects of CHB and bradycardia on myocardial structure, function, electrophysiology, and metabolism as well as for studies of cell therapy for reparation of AV conductance. 相似文献
4.
Lisbeth Brax Olofsson Olle Svensson Ronny Lorentzon Inger Lindström Håkan Alfredson 《Knee surgery, sports traumatology, arthroscopy》2007,15(5):560-563
Autologous periosteal transplantation (without chondrocyte cell transplantation) for treating traumatic articular cartilage
defects of the patella gives pain relief in uncontrolled clinical studies. To study the whole transplanted area macroscopically
and microscopically, animal studies are motivated. In this pilot study, we reproduce the surgical technique for periosteum
transplantation on human patella to a rabbit model. A full-thickness cartilage defect of the whole patella was created in
eight adult female rabbits. The defect was treated with autologous periosteal transplantation. After surgery, the rabbits
were allowed free activity. This is the difference compared to the treatment in humans, where our group uses CPM for 5 days
and non-weight-bearing for 12 weeks. After 21 weeks, there was a diffuse synovitis in all transplanted knees, and in five
of eight knees there were signs of osteoarthritis in the patello-femoral joint. Histologically, in three animals, small islands
of hyaline cartilage surrounded by fibrocartilage were seen in the transplanted area. In the other five animals, fibrocartilage
was the predominant tissue. In contrast to previous experimental studies using a rabbit model, we did not achieve hyaline
cartilage resurfacing. 相似文献
5.
The effects of brisk walking on markers of bone and calcium metabolism in postmenopausal women 总被引:5,自引:0,他引:5
Weight-bearing exercise has been shown to maintain or increase bone mass in younger as well as older individuals but the mechanisms
by which mechanical loading affects bone metabolism are not known in detail. Twelve postmenopausal women participated in a
single bout of brisk walking (50% of VO2 max) for 90 minuttes. Calciotropic hormones and markers of type I collagen formation (PICP) and degradation (ICTP) were measured
before the exercise, and 1, 24, and 72 hours following the exercise. Total body bone mineral content (BMC) and density (BMD)
were measured by dual energy X-ray absorptiometry (DXA). Brisk walking did not induce any significant changes in the concentrations
of ionized calcium, parathyroid hormone (PTH), calcitonin, or osteocalcin. A significant increase of PICP was noted 24 and
72 hours (P<0.01) after exertion and a significant decrease in the concentration of serum ICTP at 1 hour (P<0.05) was followed by an increase at 72 hours (P<0.001). There was no significant difference between the increases in the concentrations of PICP and ICTP at 72 hours. Strong
inverse correlations between the basal levels of PTH and BMD (r=−0.78;P<0.01) as well as between osteocalcin and BMD (r=−0.83;P<0.01) were noticed. The changes in serum levels of bone collagen markers indicate an altered bone collagen turnover due to
this moderate endurance exercise. The results also support the fact that serum levels of PTH as well as those of osteocalcin
are associated with total body BMD in postmenopausal women. 相似文献
6.
Toni Wendler Martin Heilemann Ronny Grunert Robert Möbius Michael Schmidt Stefan Schleifenbaum 《Journal of medical engineering & technology》2020,44(2):69-75
AbstractDiscrepancy in leg length does frequently occur as a side effect of total hip arthroplasty and may lead to reduced patient satisfaction as well as injury in the sequalae. It is consequently important to reduce leg length discrepancy where-ever technically possible. This may be achieved by recording precise intraoperative measurements and using different sized implanted components. The aim of the given study was to improve the accuracy of a previously validated optic measurement system (OMS) to reduce leg length discrepancy. This pre-existing OMS was first trialled and based on these preliminary findings developed further. Using this improved system, measurements were taken in models and cadavers. Inter observer reliability of the improved OMS was assessed. The system is introduced in the given technical feasibility study. Its accuracy was greater in the model setup (swivel joint: 772.7?±?1.5?mm; ball joint: 770.0?±?3.7?mm; reference: 772?mm) compared to the trial using cadaveric tissues (588.8?±?5.7?mm; reference: 586?mm). Results of two examiners were similar. The third one measured significantly shorter values (p=.011). The results of the measurements with the OMS indicate that a significant increase in accuracy (p?=?2.076×10?6) has been achieved compared to the previously reported system, however, a further improvement to measurement accuracy is necessary for this to be applied clinically. 相似文献
7.
Does a torn anterior cruciate ligament lead to change in the central nervous drive of the knee extensors? 总被引:2,自引:0,他引:2
Lars -Gunnar Elmqvist Ronny Lorentzon Christer Johansson Axel R. Fugl-Meyer 《European journal of applied physiology》1988,58(1-2):203-207
Summary Integrated surface electromyograms of the three superficial parts of the quadriceps and isokinetic knee extensor maximum torque and power production were recorded simultaneously and at different angular velocities in both legs in 11 male subjects with unilateral tear of the anterior cruciate ligament. The cross-sectional area (CSA) of the thigh and its muscular components were measured by computerized tomography. The principal findings were a small but significant decrease in quadriceps CSA on the affected side; a decreased active, but not passive, range of movement; decreased mechanical output, whether or not corrected for differences in CSA; and decreased electrornyographic activity — particularly in rectus femoris. These findings suggest that the reason for the decreased maximum and total knee extensor performance seen in these patients is a change in knee joint receptor afferent inflow. 相似文献
8.
EpCAM, epithelial membrane antigen (EMA)-mucin 1 (MUC1), mesothelin, and CD9 have been reported to be overexpressed at the RNA level in ovarian carcinomas. By using immunohistochemistry, we profiled the protein expression of these gene products in ovarian carcinoma tissues and compared them with benign ovarian surface epithelium (OSE) and cortical inclusion cysts (CICs). Immunoreactivity for EMA and calretinin were used to define epithelial and mesothelial differentiation in nontumor tissues, respectively. Papillary serous (n = 16) and endometrioid (n = 10) tumors were immunopositive for EMA/MUC1 (100%), mesothelin (75% and 30%, respectively), CD9 (88% and 90%, respectively), and EpCAM (100%). All ovarian carcinomas and carcinoma cell lines tested were negative for calretinin. In nonneoplastic ovary, both OSE and CICs ranged from flat-to-cuboidal to stratified and ciliated in appearance. OSE with a cuboidal morphology had a similar immunoreactivity as omental peritoneum, expressing calretinin, mesothelin, and CD9. In contrast, CICs with stratified and ciliated epithelium show expression patterns similar to those in fallopian tubes. They frequently expressed EMA, EpCAM, mesothelin, and CD9. This immunophenotype is preserved in ovarian carcinomas, suggesting that Müllerian metaplasia signals the acquisition of these markers and that their expression is maintained in ovarian carcinomas that originate from this epithelium. 相似文献
9.
Ezgi Dogan-Sander Roland Mergl Anja Willenberg Ronny Baber Kerstin Wirkner Steffi G. Riedel-Heller Susanne Rhr Frank M. Schmidt Georg Schomerus Christian Sander 《Nutrients》2021,13(6)
Depression and vitamin D deficiency are major public health problems. The existing literature indicates the complex relationship between depression and vitamin D. The purpose of this study was to examine whether this relationship is moderated or mediated by inflammation. A community sample (n = 7162) from the LIFE-Adult-Study was investigated, for whom depressive symptoms were assessed via the German version of CES-D scale and serum 25-hydroxyvitamin D (25(OH)D) levels and inflammatory markers (IL-6 and CRP levels, WBC count) were quantified. Mediation analyses were performed using Hayes’ PROCESS macro and regression analyses were conducted to test moderation effects. There was a significant negative correlation between CES-D and 25(OH)D, and positive associations between inflammatory markers and CES-D scores. Only WBC partially mediated the association between 25(OH)D levels and depressive symptoms both in a simple mediation model (ab: −0.0042) and a model including covariates (ab: −0.0011). None of the inflammatory markers showed a moderation effect on the association between 25(OH)D levels and depressive symptoms. This present work highlighted the complex relationship between vitamin D, depressive symptoms and inflammation. Future studies are needed to examine the effect of vitamin D supplementation on inflammation and depressive symptomatology for causality assessment. 相似文献
10.
Poethko-Müller Christina Kuhnert Ronny Gillesberg Lassen Sofie Siedler Anette 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(1):104-104
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Ein Erratum zu dieser Publikation wurde veröffentlicht: https://doi.org/10.1007/s00103-019-02901-5 相似文献