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21.
Victoria L Morgan Benoit M Dawant Yong Li David R Pickens 《Computerized medical imaging and graphics》2007,31(6):436-446
The objectives of this study were to use computer-generated phantoms containing real subject motion to: (1) compare the sensitivity of four commonly used fMRI software packages and (2) compare the sensitivity of three statistical analysis strategies with respect to motion correction. The results suggest that all four packages perform similarly in fMRI statistical analysis with SPM2 having slightly higher sensitivity. The most sensitive analysis technique was to perform motion correction and include the realignment parameters as regressors in the general linear model. This approach applies to all four packages examined and can be most beneficial when stimulus-correlated motion is present. 相似文献
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John Beard Victoria Westley-Wise Geoff Sullivan 《Australian and New Zealand journal of public health》1995,19(4):357-362
Abstract: Ambient air was monitored for pesticides at four sites in Coffs Harbour, a coastal town (population about 50 000) surrounded by banana plantations. Air was sampled continuously for five consecutive months during the peak agricultural spraying period using vacuum pumps set to sample one litre per minute through ORBO-42 adsorption tubes. Six pesticides were detected: three organochlorines and three organophosphates. The most commonly detected pesticide (14 per cent of all samples) was chlor-pyrifos (maximum detected level 208.0 ng/m3, mean 3.6 ng/m3). Heptachlor was detected in 7.1 per cent of all samples (maximum detected level 133 ng/m3, mean 2.7 ng/m3). Other pesticides were only rarely detected. The only pesticide applied by air in the district (propiconazole) was not detected. If international health guidelines are used as a yardstick, these levels of exposure appear unlikely to present an appreciable health risk. Chlorpyrifos detection was associated with low wind speed (P = 0.012) and high temperature (P = 0.015), and detection at one site was associated with detection at another (P < 0.001). Chlorpyrifos detection was also associated with domestic applications within the town area as reported by pesticide applicators (P = 0.045). Peak agricultural use of chlorpyrifos did not coincide with peak detection periods. None of the detected organochlorines is registered for agricultural use, although at the time, heptachlor was permitted for use as a domestic termiticide. Even in a semirural town with nearby widespread use of agricultural chemicals, community exposures to pesticides in ambient air may largely relate to their nonagricultural use. 相似文献
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The first part of this paper addresses the issues of profession and professionalisation which affect educators in physiotherapy undergraduate studies. It introduces ‘profession’ and ‘professionalisation’ in isolation, although it is not the intention to simplify discussion, but instead to explore the concepts as they stand from a wider perspective before applying them to physiotherapy education. This is followed by a consideration of the complex issues of physiotherapy itself as an aspiring profession, based upon the elements of a profession previously identified, before introducing the role of physiotherapy education and research within the professionalisation process. Part 2 continues this theme by offering a critical analysis of the overlap between education, research and professional status.The second and concluding part of this article continues the theme of professionalisation within physiotherapy, yet more specifically addresses the issues of professionalisation within academia. It provocatively considers physiotherapy academic educators themselves as jugglers of two values – the producers of future professionals and the aspirational creators of a profession. This theme is then expanded by an analysis of the demands placed upon physiotherapy educators, from the perspective both of promoting the profession, and of identifying physiotherapy educators' values. A summary of the discussion follows, outlining emerging points for future development.This paper finally proposes how physiotherapy educators need to revisit the values that underpin their role, and how the professionalisation of future physiotherapists depends upon both a sound understanding and respect of educational philosophy and educational research. The creation and support of a ‘profession’ of physiotherapy educators is offered as a medium through which they can reflect upon and evaluate their own practice within the discipline of education. 相似文献
24.
Sandra Guerra A Teixeira Pinto José Ribeiro José Oliveira José Duarte Jorge Mota 《Revista portuguesa de cardiologia》2003,22(2):167-182
An important aspect of preventive medicine is to identify subjects at risk as soon as possible, so preventive strategies can be introduced at early ages. The justification for this strategy is twofold: firstly, the assumption that children maintain a particular high value of a risk factor for disease throughout life; and secondly, the assumption that lowering the level of the risk factor in early life will have a greater impact on the disease than will risk factor changes in later life. In epidemiology the analysis of such factors over time is referred to as tracking. Tracking analysis has been applied to risk factors for cardiovascular diseases (CVD) in pediatric years. The aims of this study were: I) to analyze the stability of biological risk factors [high blood pressure (BP), high percentage of fat mass (%FM) and high total cholesterol (TC)] and lifestyle risk factors [low physical activity index (PAI)] in isolation; and II) to analyze the stability of zero, one, two or three biological risk factors. There were two evaluations in 692 children and adolescents (325 boys and 367 girls), aged between 8 and 15 years. The quartiles, adjusted for age and gender, were the criterion used to identify subjects with biological risk factors (fourth quartile) and with lifestyle risk factors (first quartile) for CVD. The stability was calculated through the relative frequency of subjects who maintained or changed quartile between the two evaluations. There is stability for biological risk factors as well as for behavioral and/or lifestyle risk factors. However, the highest stability is seen in biological risk factors. 相似文献
25.
The effects of HgCl2 on the epidermis of Trichomycterus brasiliensis were studied by histological, histochemical, and ultrastructural methods. First, the normal organization of the tissue was described in order to study the HgCl2 effects on the skin structure. The epithelial cells presented a typical structural organization found in many fishes. Basically five types of cells could be detailed: goblet cells, club cells, germinative stratum cells, intermediate layer cells, and epithelial cells in the superficial layer. The goblet cells in the superficial layer present evidence of secretory activity by positive histochemical reactions. In cells exposed to HgCl2, different morphological alterations were observed in the epithelium structure, such as an increase in the lymphocyte number, hypertrophied epithelial cells at the surface, modified taste buds, obstruction of the goblet cells pore, and high cellular proliferation. Moreover, the chemical nature of the goblet cells was not modified by the presence of the HgCl2 dissolved in water. All animals died within 24 hr after the contamination with inorganic mercury at concentrations of 0.2 and 0.1 mg HgCl2/liter. 相似文献
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Adjuvant tamoxifen for male breast cancer (MBC). 总被引:3,自引:0,他引:3
A study was started in 1976 whereby patients with Stage II and operable Stage III MBC were given adjuvant Tamoxifen for 1 year, increasing to 2 years from 1988. All patients had axillary nodal involvement. Primary treatment consisted of a radical mastectomy or simple mastectomy with radiotherapy. The rarity of the disease precluded a randomised trial. Thirty-nine patients are available for analysis at a median follow-up of 49 months. The actuarial survival of the Tamoxifen treated patients is 61% (range 42-80%) at 5 years compared to 44% (range 35-53%) for historical controls (P = 0.006). Disease-free survival was 56% (37-75%) vs 28% (17-33%) at 5 years (P = 0.005). There were no serious side-effects recorded. The conclusion from this, the first reported series on adjuvant Tamoxifen therapy for MBC, is that significant improvement in disease-free survival can be achieved with minimal upset to the patients. Recruitment to the study continues. 相似文献
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