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Jeffery JA  Ong TJ 《Injury》2000,31(3):135-138
We have assessed the consistency of measurement of femoral head circumference using 3 standard measuring instruments used in hemiarthroplasty of the hip. Fifty femoral heads were independently sized by ten independent observers using a caliper, a half circular measuring template, each allowing measurement to the nearest millimeter.We found significantly greater variance of the results using the half-circular templates (p=0.001) and the calipers (p=0. 011) compared with the full circular measuring templates. Measurement with calipers underestimated femoral head size by 0.72 mm compared with full circular measuring templates (p=0.02). Insertion of an undersized hemiarthroplasty head is a cause of increased point loading of the acetabulum and may result in increased rates of acetabular erosion. The use of full circular measurement templates is recommended as the most consistent method for head sizing in hemiarthroplasty of the hip.  相似文献   
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ObjectiveThe aims of this study were (1) to investigate willingness to pay (WTP) for preventive and curative dental care procedures and (2) to determine the factors that influence older adults’ WTP for dental care.MethodologyOlder, independently living adults from Singapore aged 60 years and older and eligible for government-subsidised dental care were nonrandomly recruited for this study. Data were collected using questionnaires and a clinical examination which recorded details of caries experience, number and distribution of posterior occluding contacts, prosthodontic status, and periodontal status. Using a contingent valuation method, participants were asked to rate WTP in Singapore dollars [SGD$] for 4 aspects of care: dental fillings, dental scaling, dental extraction, and disease prevention advice. Negative binomial regression was used to assess the relationship between the predictor variables associated with WTP for dental fillings, scaling, extraction, and preventive advice.ResultsThe mean value of WTP for a dental filling was SGD$30.23 (SGD$31.05), for scaling was SGD$30.28 (SGD$29.46), for dental extraction was SGD$35.08 (SGD$58.54). In a multivariate model, factors associated with higher WTPfees were as follows: (1) dental filling: age (younger), level of education (higher), and frequency of dental visits (regular); (2) scaling: level of education (higher), agree that dental problems affect overall health, and frequency of dental visits (regular); (3) dental extractions: age (younger), level of education (higher), frequency of dental visits (regular), and prosthodontic status (not wearing); (4) preventive advice: age (younger), gender (male), ethnicity (Chinese), level of education (higher), marital status (married), self-perceived oral health (good), and dental visits (regular).ConclusionsThe findings of our study suggest that older adults are willing to pay most for extraction and least for preventive advice.Key words: Geriatric, Oral health, Health economics, Health attitudes  相似文献   
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Pregnenolone and its sulphate had concentration-dependent dual actions on gamma-aminobutyric acid (GABAA)-receptor-mediated ileal contractile responses, enhancing at 0.001-1 microM but inhibiting at 10 microM. There was a sinistral shift of the GABA dose-response curve in the presence of 0.01 microM pregnenolone, with a significant potentiation over the lower concentration range of GABA (3-30 microM), whilst 10 microM pregnenolone depressed the curve by 50% without a significant change in the EC50, in a manner resembling non-competitive inhibition with picrotoxin. Pregnenolone and its sulphate evidently have modulatory actions at ileal GABAA-receptor complexes in keeping with those seen using neurochemical studies in the central nervous system.  相似文献   
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When people encounter others’ emotions, they engage multiple brain systems, including parts of the sensorimotor cortex associated with motor simulation. Simulation-related brain activity is commonly described as a ‘low-level’ component of empathy and social cognition. It remains unclear whether and how sensorimotor simulation contributes to complex empathic judgments. Here, we combine a naturalistic social paradigm with a reliable index of sensorimotor cortex-based simulation: electroencephalography suppression of oscillatory activity in the mu frequency band. We recruited participants to watch naturalistic video clips of people (‘targets’) describing emotional life events. In two experiments, participants viewed these clips (i) with video and sound, (ii) with only video or (iii) with only sound and provided continuous ratings of how they believed the target felt. We operationalized ‘empathic accuracy’ as the correlation between participants’ inferences and targets’ self-report. In Experiment 1 (US sample), across all conditions, right-lateralized mu suppression tracked empathic accuracy. In Experiment 2 (Israeli sample), this replicated only when using individualized frequency-bands and only for the visual stimuli. Our results provide novel evidence that sensorimotor representations—as measured through mu suppression—play a role not only in low-level motor simulation, but also in higher-level inferences about others’ emotions, especially when visual cues are crucial for accuracy.  相似文献   
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