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Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest.  相似文献   
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In the past, addiction disorders were considered to be mainly substance use disorders. The main focus has been on dependence disorders. Dependence criteria do not differ substantially in the two main classification systems ICD and DSM, while harmful use (ICD) and abuse (DSM) criteria show much less concordance. Presently diagnostic criteria for behavioral addiction disorders are only available for pathological gambling, however, under the category of disorders of impulse control, while other disorders have to be categorized under disorders not otherwise specified. Evidence of neurobiological similarities implies that future ICD and DSM revisions, in addition to other needed changes, will group behavioral addiction and substance use disorders together.  相似文献   
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Within the treatment algorithm for accident victims there is an additional risk potential beyond those associated with the complex treatment procedures in primary medical care, and it is inherent in the interfaces between the different treatment sectors. Besides the substantial loss of time and information, such factors as technical incompatibilities between items of equipment, differing treatment concepts and responsibilities and difficulties in transfer and positioning can put the patient at risk. The entire process involves multiple interfaces both between preclinical and clinical medical care and within the various treatment sectors, e.g. when a preclinical patient is transferred from ground medical staff to the air rescue team. The goal of an efficient treatment algorithm should be the reduction of multiple interfaces in order to optimize the various procedures. Future concepts directed at optimizing trauma management should therefore make some contribution to interface reduction.  相似文献   
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A multiply injured patient’s airway is primarily secured with a laryngeal tube by the responding EMS. For helicopter transfer the flight physician decides not to intubate the patient’s trachea. Mechanical ventilation was performed without complications.  相似文献   
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