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A population-based study on 1008 postmenopausal women identified that the 24% of women achieving high levels of PA and CI had 3.4-4.4% higher femoral bone strength in axial compression and 1.7-5.2% in bending than those achieving low levels, indicating that lifestyle factors influence bone strength in the proximal femur. INTRODUCTION: Extensive research has shown that increased physical activity (PA) and calcium intake (CI) decrease the rate of bone loss; however, there is little research on how these lifestyle variables affect bone geometry. This study was designed to investigate the effects of modifiable lifestyle variables, habitual PA and dietary CI, on femoral geometry in older women. MATERIALS AND METHODS: Femoral geometry, habitual PA, and dietary CI were measured in a population-based sample of 1008 women (median age+/-interquartile range, 75+/-4years) enrolled in a randomized controlled trial (RCT) of calcium supplementation. Baseline PA and CI were assessed by validated questionnaires, and 1-year DXA scans (Hologic 4500A) were analyzed using the hip structural analysis technique. Section modulus (Z), an index of bending strength, cross-sectional area (CSA), an index of axial compression strength, subperiosteal width (SPW), and centroid position, the position of the center of mass, were measured at the femoral neck (NN), intertrochanter (IT), and femoral shaft (FS) sites. These data were divided into tertiles of PA and CI, and the results were compared using analysis of covariance (ANCOVA), with corrections for age, height, weight, and treatment (calcium/placebo). RESULTS AND CONCLUSIONS: PA showed a significant dose-response effect on CSA all hip sites (p<0.03) and Z at the narrow neck and intertrochanter sites (p<0.02). For CI, there was a dose-response effect for centroid position at the intertrochanter (p=0.03). These effects were additive, such that the women (n=240) with PA in excess of 65.5 kcal/day and CI in excess of 1039 mg/day had significantly greater CSA (NN, 4.4%; IT, 4.3%; FS, 3.4%) and Z (NN, 3.9%; IT, 5.2%). These data show a favorable association between PA and aspects of bone structural geometry consistent with better bone strength. Association between CI and bone structure was only evident in 1 of 15 variables tested. However, there was evidence that there may be additive effects, whereby women with high levels of PA and CI in excess of 1039 mg/day had significantly greater CSA (NN, 0.4%; FS, 2.1%) and Z (IT, 3.0%) than women with high PA but low CI. These data show that current public health guidelines for PA and dietary CI are not inappropriate where bone structure is the health component of interest.  相似文献   
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Coagulase negative staphylococci have long been thought to be harmless skin commensals. However they are now recognised as important pathogens in patients who have undergone insertion of prosthetic devices. We present three patients with infection following the insertion of silicone polymer prostheses, in whom a coagulase negative staphylococcus was the pathogen. All responded to antibiotic treatment. It is important to alert the bacteriologist to the presence of an implanted prosthesis when wound swabs are sent from an area showing clinical signs of infection. The coagulase negative staphylococci may otherwise be regarded falsely as merely skin contaminants.  相似文献   
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We report a case of severe hyponatraemia and hypoglycaemia in a patient with complicated falciparum malaria. The use of large volumes of intravenous dextrose as a diluent for quinine may lead to fluid overload and exacerbate hyponatraemia.  相似文献   
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On-line imaging of prostate markers can be used to compensate for errors in radiation delivery. This study assessed the patient acceptability and morbidity associated with the trans-perineal route of implantation. A minority experienced acute pain or bleeding. Placement was accurate in all but one subject. An operator related learning curve exists. Although this is an invasive procedure most patients found it acceptable. Implementation for routine clinical practice is feasible.  相似文献   
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Ptosis is known to be associated with thyroid disorders. We describe two biochemically corrected hypothyroid patients presenting with isolated bilateral ptosis. EMG of the orbicularis oculi showed continuous grouped motor unit potentials. In the absence of obvious aetiology, it is hypothesised that focal demyelination of terminal branches to the orbicularis oculi may play a role in the generation of the discharges.  相似文献   
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We report a case of refractory bladder fistula in a diabetic renal allograft recipient that recurred shortly after conventional operative repair without any detectable external cause. After reoperation and use of a vascularized rectus muscle flap the fistula closed and the patient has retained excellent graft function. It is suggested that this technique should be considered as the primary repair modality for bladder fistulas in diabetic recipients, when wound healing is impaired seriously as a consequence of the combined effects of diabetic microangiopathy and steroid therapy.  相似文献   
10.
Screening assays for immunologic infertility: a comparison study.   总被引:1,自引:0,他引:1  
Because the immunobead antisperm antibody test (IBT) is difficult to learn and results are heavily operator-dependent, we compared findings on IBT with those of SpermMAR and SpermCheck in 58 patients to determine whether the latter two tests could demonstrate improved screening ability. Assays performed on both sperm and serum (i.e., direct and indirect) yielded 100% positive predictive values when IBT was used as the standard. Both SpermCheck and SpermMAR are easier to perform, and, as the former has a slightly greater sensitivity, we recommend SpermCheck for the detection of immunologic infertility.  相似文献   
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