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31.
Bone mineral density in professional female dancers.   总被引:4,自引:4,他引:0       下载免费PDF全文
OBJECTIVES: To measure the long term effects of dance training and the contribution of the timing and duration of any menstrual disruption on bone mineral density (BMD). DESIGN: Measurement of BMD in 57 premenopausal, previously professionally dance trained women and the relationship to menstrual and training history. MAIN OUTCOME MEASURES: Bone density measurements at lumbar spine and femoral neck by dual energy x-ray absorptiometry. RESULTS: The average Z score for BMD at the lumbar spine in the amenorrhoeic dancers was significantly below that for the normal population. The average Z score for BMD at the femoral neck in the eumenorrhoeic dancers was significantly above that for the normal population. There was a significant difference between the average Z score for BMD at both the lumbar spine and femoral neck between the amenorrhoeic and eumenorrhoeic dancers. Significant negative relationships were found between BMD at the lumbar spine and (1) age at menarche, (2) duration of amenorrhoea, (3) BMD at the femoral neck, and (4) the variable of ideal minus lowest weight, which was independent of amenorrhoea. No significant relationships were found between duration of oral contraceptive pill usage and BMD at either the lumbar spine or the femoral neck in eumenorrhoeic or amenorrhoeic dancers. In order to quantify the effect of a combination of these significant factors, a model of BMD was constructed using multiple regression incorporating the variables duration of amenorrhoea, age at menarche, and ideal minus lowest body weight. In this model R2 was 33.6%, in other words 33.6% of the total variation in the Z score for BMD at the lumbar spine could be accounted for by these factors. CONCLUSION: Professional female dancers with a history of delayed menarche and amenorrhoea have been identified as another group of premenopausal women potentially at risk of developing osteoporosis because of a decrease in BMD at the lumbar spine. The femoral neck in dancers with a history of amenorrhoea was partially protected from loss of BMD by virtue of being the major weight bearing site in previous dance training, and in eumenorrhoeic dancers BMD was significantly increased at this site.  相似文献   
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A pilot study was undertaken to assess the respiratory component of primary care nurses' working time. 13 nurses were interviewed and 10 completed a diary during one working week. The nurses spent a mean 6.6% of their time caring for those with respiratory disease and were of the opinion that during this time they undertook 68% of the management of long term respiratory illness in the practices. More time was spent with those with asthma than with other respiratory conditions and the nurses felt that they were appropriately trained for the tasks undertaken. However, with more training they felt that they could undertake more basic care of those patients with COPD, and more advanced care of those patients with asthma.  相似文献   
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Summary: This study was undertaken to determine maternal impact of corticosteroids administered for the promotion of fetal lung maturity in mothers with the HELLP syndrome. Twenty-seven of 427 women with the HELLP syndrome treated between 1980–1991 received a full course of steroids prior to preterm delivery. This group was compared to 27 matched control patients with the HELLP syndrome who received no corticosteroids. Subjects were matched for maternal age, race, sex of the fetus, and severity of the HELLP syndrome. The antepartum platelet count stabilized or increased in 25 of 27 steroid-treated women in contrast to 0 of 15 control women (p <0.00001). In comparison to control patients, LDH serum concentrations in steroid-treated patients stabilized or decreased and the SGOT/AST and SGPT/ALT stabilized or decreased during therapy (p < 0.005). The interval from delivery to platelet nadir in patients with Class III HELLP syndrome was shorter in the steroid-treated group (p<0.008) than in untreated patients.  相似文献   
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.A sedation regimen using sequential oral trinepazine, intravenous Pethco (pethidine, chlorpromazine and promethazine) and diazemuls was evaluated in children having native kidney (n = 17) and transplant kidney (n = 17) biopsies. Biopsy was successful in all cases, with no serious side effects. A self-reported scale of memory recall and pain perception showed the optimal time for biopsy to be between 30 and 90 min after the intravenous Pethco. The child’s level of distress was measured by a self-reported scale, a parent-reported scale and an observational scale for doctors and nurses; 45% of children rated themselves highly distressed prior to the procedure, their parents being the best assessors of this distress. Younger children and those undergoing native kidney biopsy had less understanding of the procedure. Children’s worries could be clearly categorised into procedural and outcome issues: those undergoing transplant biopsy were more worried about outcome, whereas those undergoing native kidney biopsy were more worried about the procedure. Received April 3, 1995; received in revised form and accepted April 17, 1996  相似文献   
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The exposures of building maintenance personnel and occupants to airborne asbestos fibers, and the effects of operations and maintenance programs on those exposures, continue to be an important public health issue. The subject of this investigation was a large metropolitan county with numerous public buildings which routinely conducted air sampling for asbestos. A total of 302 personal air samples in nine task categories collected during maintenance worker activities in proximity to asbestos-containing materials were analyzed; 102 environmental air samples in four task categories were also analyzed. The arithmetic means of the 8-hr time weighted average exposures for personal sampling for each task category were all below the Occupational Safety and Health Administration permissible exposure level of 0.1 fibers (f)/cc > 5 μm. The highest mean 8-hr time weighted average exposure was 0.030 f/cc > 5 μm for ceiling tile replacement. The maximum asbestos concentration during sample collection for environmental samples was 0.027 f/cc > 5 μm. All asbestos-related maintenance work was done within the framework of an Operations and Maintenance Program (OMP) which utilized both personal protective equipment and controls against fiber release/dispersion. Results are presented in association with specific OMP procedures or controls. These results support the effectiveness of using Operations and Maintenance Programs to manage asbestos in buildings without incurring unacceptable risk to maintenance workers performing maintenance tasks.  相似文献   
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Stereoscopic depth perception is possible when the short wave sensitive (SWS or "Blue") cones are isolated using a yellow adapting field. We have measured the maximum disparity that can be fused (the diplopia threshold) as a function of the separation between pairs of dots or lines. Under all conditions, these diplopia thresholds are the same for the isolated SWS cones as for the entire visual system. In addition, SWS diplopia thresholds vary as a linear function of dot or line separation, so that they exhibit disparity scaling. Further experiments show that disparity scaling is dependent upon the presence of low spatial frequencies in the stimulus and not upon the retinal eccentricity of stimulation. These data indicate that the SWS cones provide information to the disparity processing system through more than one low spatial frequency channel but not through high frequency ones.  相似文献   
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