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111.
Individuals' rationality has been a key issue long debated in Economics. While normative theories establish the way 'rational' consumers should behave, many empirical studies have documented numerous systematic violations of normative principles. This has led some to question the validity of classic economic models as an adequate approximation of individuals' real decision-making. This paper aims to shed more light on this debate. A stated preference choice experiment was set up to test rational choice properties. Attention was given to the extent to which satisfaction of such tests is related to both the complexity of the design, and subject characteristics. Quantitative and qualitative methods are applied. The majority of respondents passed the rationality tests. Satisfaction of the tests was sensitive to normatively irrelevant factors such as the complexity of the task and demographic characteristics. A significant proportion of those individuals who 'failed' seem to have reformulated the experiment in some way in their mental process. Implications for the design and analyses of future DCEs are discussed. 相似文献
112.
The authors wished to assess medical students' attitudes towards communication skills learning, and to validate the use of the Communication Skills Attitude Scale (CSAS) in a different population. This cross-sectional study of Years 1-3 MBChB students, University of Aberdeen, in 2002-03 (overall response rate=86.2%) identified significant differences in attitudes to communication skills teaching by year of study and gender. PAS (positive attitudes scores) for Year 1 were significantly higher than those for Years 2 and 3. NAS (negative attitudes scores) for Year 1 were significantly lower than the scores for Year 2 but not Year 3. The scores for Years 2 and 3 were not significantly different. Female students had a significantly higher mean PAS score and lower mean NAS score than males, and were more likely to disagree that their communication and clinical skills were competent. While cohort effects may be present, it seems that attitudes towards communication skills learning are positive initially, becoming less so until students experience interacting with patients. Differences between male and female students reflect those seen in previous studies. The findings presented support the use of the CSAS as an appropriate tool to measure attitudes in a wide population of medical students. 相似文献
113.
Nutritional correlates of dietary glycaemic index: new aspects from a population perspective 总被引:1,自引:0,他引:1
Schulz M Liese AD Mayer-Davis EJ D'Agostino RB Fang F Sparks KC Wolever TM 《The British journal of nutrition》2005,94(3):397-406
The role of dietary glycaemic index (GI) and glycaemic load (GL) in disease aetiology is of increasing interest. However, nutritional factors related to dietary GI and GL are not well understood from a population perspective. We aimed to investigate the relation ship between GI and GL and dietary intake at the food and nutrient level. Study subjects were 1071 non-diabetic adults from the Insulin Resistance Atherosclerosis Study, Exam I, 1992-4. Usual dietary intake was assessed with a 114-item modified Block food frequency questionnaire. Published GI values were assigned to food line items. Correlation and regression analyses were conducted. Intake of white bread, beer, meats and fries/fried potatoes was positively associated with average GI, as was fat, starch and alcohol intake (before and after energy adjustment). Intake of fruits and low-fat milk was inversely associated with GI, as were intakes of mono- and disaccharides, and fibre. GL was positively correlated with carbohydrate foods and inversely with non-carbohydrate foods. Gender-specific regression models identified eight food groups explaining 63% (men) and 55% (women) total GI variation after adjusting for demographics; 70% of variation in GL was explained by eleven (men) and nine (women) food groups, respectively. Although the GI of a food is an indicator of the ability of carbohydrates to raise blood glucose, dietary GI, unlike GL, appears to reflect more dimensions of diet than just carbohydrates, such as the combination of foods consumed. This may have implications for the interpretation of dietary GI in epidemiologic studies. 相似文献
114.
115.
Binaural redundancy and inter-aural time difference cues for patients wearing a cochlear implant and a hearing aid in opposite ears 总被引:1,自引:0,他引:1
We investigated speech perception advantages arising from the use of inter-aural time difference cues, and from the provision of redundant information by the use of a hearing aid contralateral to a cochlear implant (bimodal hearing devices). Thirty-eight subjects (14 normally hearing and 23 hearing-impaired) participated in this study. The effect of binaural redundancy was assessed by comparing the signal-to-noise ratio (SNR) required for 50% correct identification of sentences in noise when listening monaurally to that when listening binaurally. The use of inter-aural time difference cues was determined by comparing the binaural SNRs obtained with or without a noise delay of 700 micros between ears. Results indicated adults who used bimodal hearing devices benefited from binaural redundancy, but children did not. Whereas normally hearing subjects used inter-aural time difference cues to improve speech perception in noise, neither adults nor children who used bimodal hearing devices were able to do so. 相似文献
116.
Murthy KK Mahboubi VS Santiago A Barragan MT Knöll R Schultheiss HP O'Connor DT Schork NJ Rana BK 《Human mutation》2005,26(2):145-152
The identification of common genetic variants such as single nucleotide polymorphisms (SNPs) in the human genome has become central in human population genetics and evolution studies, as well as in the study of the genetic basis of complex traits and diseases. Crucial for the accurate identification of genetic variants is the availability of high quality genomic DNA (gDNA). Since popular sources of gDNA (buccal cells, lymphocytes, hair bulb) often do not yield sufficient quantities of DNA for molecular genetic applications, whole genome amplification methods have recently been introduced to generate a renewable source of double-stranded linear DNA. Here, we assess the fidelity of one method, multiple displacement amplification (MDA), which utilizes bacteriophage Phi29 DNA polymerase to generate amplified DNA from an original source of gDNA, in a representative SNP discovery and genetic association study at the melanocortin 1 receptor (MC1R) locus, a highly polymorphic gene in humans involved in skin and hair pigmentation. We observed that MDA has high fidelity for novel SNP discovery and can be a valuable tool in generating a potentially indefinite source of DNA. However, we observed an allele amplification bias that causes genotype miscalls at heterozygous sites. At loci with multiple polymorphic sites in linkage disequilibrium, such as at MC1R, this bias can create a significant number of heterozygote genotype errors that subsequently misrepresents haplotypes. 相似文献
117.
The main resource of the NHS is its workforce. However, achieving the correct mix of staff is crucial if it is to provide high-quality patient care in a cost-effective manner. When an acute trust was singled out in an independent analysis as having 'too rich' a skill-mix (compared with the rest of the strategic health authority), an internal review was undertaken to determine the ratio of qualified to unqualified nursing staff, and to compare these with acuity and dependency in each clinical area. The information was used to revise the nursing skill-mix within the trust. 相似文献
118.
This article describes a pilot study to evaluate washable (or reusable) absorbent garments for adults with moderate to heavy urinary incontinence. The article will describe: The study process; How the individual products performed and how the washable and disposable products compared; How nurses can enable their patients to use washable products appropriately. 相似文献
119.
STUDY OBJECTIVE: To report that leukocyte-mediated acute injury may develop in a nonhypoxic lung after hypoxia-reoxygenation injury of the hypoxic lung and in other systemic organs in patients with reexpansion pulmonary edema. DESIGN: Case report analysis with examination of the literature. SETTING: Intensive care unit of a university hospital. PATIENTS: Three patients who developed leukocyte-mediated acute lung injury in the contralateral lung and systemic organ injury after ipsilateral reexpansion pulmonary edema of a collapsed lung. MEASUREMENTS: To rule out the possibility that the acute lung injury in the contralateral lung was an extension of the hypoxia-reoxygenation injury, we analyzed changes in leukocyte and platelet count in the peripheral blood in relation to the development of pulmonary edema in each lung. Changes in liver enzymes were also analyzed to detect hepatic dysfunction as evidence of systemic organ injury. MAIN RESULTS: Both leukocyte and platelet counts decreased when reexpansion pulmonary edema developed, and decreased further when acute lung injury developed in the contralateral lung (F = 8.42, p = 0.037 for leukocytes, and F = 17.66, p = 0.01 for platelets). Significant hepatic dysfunction developed, as evidenced by increases in both serum bilirubin (p = 0.001) and lactic dehydrogenase, indicating the presence of systemic organ injury. CONCLUSIONS: The hypoxia-reoxygenation injury of one lung can induce acute lung injury in the other lung and systemic organ injury. 相似文献
120.
Barnett M 《The Practitioner》2004,248(1659):392-4, 399-400, 403 passim