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Alcohol consumption by young actively growing rats has been previously demonstrated to decrease cortical and cancellous bone density, to reduce trabecular bone volume, and to inhibit bone growth at the epiphyseal growth plate. This study addresses the action of alcohol on cortical bone growth using histomorphometric techniques and on mechanical properties by three-point bending. Four-week-old, female Sprague-Dawley rats were divided into three groups. Alcohol-treated animals were fed a modified Lieber-DeCarli diet ad libitum containing 35% ethanol-derived calories, whereas the pair-fed animals (weight-matched to ethanol rats) received an isocaloric liquid diet in which maltose-dextrin-substituted calories were supplied by ethanol. Chow animals were fed a standard rat chow ad libitum. Femora were removed for analysis after 2, 4, 6, or 8 weeks on the diets. Cortical bone area, bone formation rates, and mineral apposition rates were reduced in the alcohol-fed animals. Bone stiffness, strength, and energy absorbed to fracture were significantly lower in the alcohol-fed animals. This distinctive alcohol effect was revealed to be caused by lower quality bone tissue as reflected by lower elastic moduli and yield strengths. 相似文献
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Disturbed eating behaviour and disturbed body experience are important features for the differential diagnosis of eating disorders from other disorders. Eating disorders occur mainly in young females. The one-year prevalence of anorexia nervosa is 0.4% and that of bulimia nervosa 1.5% among young females. To motivate patients for treatment it is important to discuss physical problems and the high risk of severe complications with them. It is difficult to motivate patients for treatment, because anorexia nervosa patients deny their illness and bulimia nervosa patients are ashamed and hide their disturbed eating behaviour. The treatment of anorexia nervosa consists of two partly overlapping phases: normalizing the eating pattern to improve weight restoration and psychotherapeutic treatment for underlying emotional problems. Family therapy is effective for patients younger than 18 years with a short duration of illness. Cognitive behaviour therapy is the most important form of treatment for bulimia nervosa. 相似文献
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S Ritz A Turzynski HW Schütz A Hollmann G Rochholz 《Canadian Metallurgical Quarterly》1996,77(1-2):13-26
Age at death determination based on aspartic acid racemization in dentin has been applied successfully in forensic odontology for several years now. An age-dependent accumulation of D-aspartic acid has also recently been demonstrated in bone osteocalcin, one of the most abundant noncollagenous proteins of the organic bone matrix. Evaluation of these initial data on in vivo racemization of aspartic acid in bone osteocalcin was taken a step further. After purification of osteocalcin from 53 skull bone specimens, the extent of aspartic acid racemization in this peptide was determined. The D-aspartic acid content of purified bone osteocalcin exhibited a very close relationship to age at death. This confirmed identification of bone osteocalcin as a permanent, 'aging' peptide of the organic bone matrix. Its D-aspartic acid content may be used as a measure of its age and hence that of the entire organism. The new biochemical approach to determination of age at death by analyzing bone is complex and demanding from a methodologic point of view, but appears to be superior in precision and reproducibility to most other methods applicable to bone. 相似文献