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61.
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
62.
Marla E. Salmon Jean Yan Hermi Hewitt Victoria Guisinger 《Health services research》2007,42(3P2):1354-1372
Objective. To (1) provide a contextual analysis of the Caribbean region with respect to forces shaping the current and emerging nursing workforce picture in the region; (2) discuss country-specific case(s) within the Caribbean; and (3) describe the Managed Migration Program as a potential framework for addressing regional and global nurse migration issues.
Principal Findings. The Caribbean is in the midst of a crisis of shortages of nurses with an average vacancy rate of 42 percent. Low pay, poor career prospects, and lack of education opportunities are among the reasons nurses resign. Many of these nurses look outside the region for job opportunities in the United Kingdom, Canada, the United States, and other countries. Compounding the situation is the lack of resources to train nurses to fill the vacancies. The Managed Migration Program of the Caribbean is a multilateral, cross-sector, multi-interventional, long-term strategy for developing and maintaining an adequate supply of nurses for the region.
Conclusions. The Managed Migration Program of the Caribbean has made progress in establishing regional support for addressing the nursing shortage crisis and developing a number of interesting initiatives such as training for export and temporary migration. Recommendations to move the Managed Migration Program of the Caribbean forward focus on advocacy, integration of the program into regional policy decisions, and integration of the program with regional health programming. 相似文献
Principal Findings. The Caribbean is in the midst of a crisis of shortages of nurses with an average vacancy rate of 42 percent. Low pay, poor career prospects, and lack of education opportunities are among the reasons nurses resign. Many of these nurses look outside the region for job opportunities in the United Kingdom, Canada, the United States, and other countries. Compounding the situation is the lack of resources to train nurses to fill the vacancies. The Managed Migration Program of the Caribbean is a multilateral, cross-sector, multi-interventional, long-term strategy for developing and maintaining an adequate supply of nurses for the region.
Conclusions. The Managed Migration Program of the Caribbean has made progress in establishing regional support for addressing the nursing shortage crisis and developing a number of interesting initiatives such as training for export and temporary migration. Recommendations to move the Managed Migration Program of the Caribbean forward focus on advocacy, integration of the program into regional policy decisions, and integration of the program with regional health programming. 相似文献
63.
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
64.
S Thurber A Chronopoulos C E Stafstrom G L Holmes 《Brain research. Developmental brain research》1992,68(1):35-40
There is controversy as to whether prolonged seizures are more detrimental to the immature than the mature brain. To evaluate this question continuous hippocampal stimulation was used to induce prolonged limbic seizures in 20-, 30- and 60-day-old rats. The long-term effects on learning and activity level were then studied at age 80 days using the Morris water maze, a test of spatial learning and memory, and the open field test, a test of an animal's reaction to a novel environment. Limbic status epilepticus in 60-day-old but not 20- and 30-day-old rats caused long-term impairment of learning in the Morris water maze. No differences were noted between the control and the experimental animals in the open field test. These results suggest that the age of seizure onset is an important determinant of long-term cognitive sequelae. 相似文献
65.
Background : Osseous cranial base tumours in children present as a diverse collection of both benign and malignant pathologies. Concerns raised by the difficulty in accurate diagnosis and local recurrence of benign lesions and by the long-term sequelae of radiotherapy for malignant cranial tumours (marked local growth disturbances, pituitary dysfunction, visual disturbances, late new tumour induction) prompted an evaluation of surgical resection of cranial base tumours in children, with specific regard to safety, efficacy and aesthetic result. Methods : A retrospective review was performed of 10 consecutive children presenting with tumours either arising from or eroding into bone of the cranial base who were managed by surgical resection in a 10-year period from 1986 to 1996. The patients demonstrated a great variation in both presentation and pathology. All underwent surgical resection of tumour with reconstruction where indicated. Results : There were no postoperative complications or mortality. All patients remained clinically free of disease at follow-up, which ranged from 17 months to 9 years (mean 6 years and 4 months). Conclusion : The aggressive surgical resection and craniofacial reconstruction of cranial base tumours in the paediatric population offers a safe and efficacious mode of treatment that obviates problems of diagnosis and local recurrence for benign lesions and of the long-term sequelae of radiotherapy for malignant lesions. 相似文献
66.
Harold O. Goodman Robert Brommage Dean G. Assimos Ross P. Holmes 《World journal of urology》1997,15(3):186-194
An examination of the urinary excretions of 101 normal subjects indicated that the major genetic influence on calcium excretion is a codominant pair of alleles giving rise to three phenotypes, low, intermediate and high (hypercalciuric) excretors. This inference was based on variance, Hardy-Weinberg and segregation analyses. Similar independent gene pairs also appear to influence oxalate and citrate excretion, A 3-locus Hardy-einberg table using estimates of gene frequencies derived from the study of normals suggests that only 3 or 4 leading genes are involved in oxalate stone disease. Strong candidate genes identified from molecular and physiological studies cannot be proposed at present, but it is assumed that they influence the transport of these ions in either the intestine, kidney or both organs. The identification of the genes involved should be facilitated by the reduction of dietary influences on urinary excretions through the use of formula diets. 相似文献
67.
68.
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
69.
Self-report questionnaires completed by young adults with Type I diabetes were examined to determine if individuals differing in recent metabolic control (Poor, Moderate or Very Good) or disease duration (Long, Short) also vary in either occurrence or type of life events during the past year or occurrence of recent emotional distress. Subjects in Poor control reported more positive and neutral life events during the past year, suggesting even those life changes individuals view benignly may be associated with metabolic control difficulties. Individuals in Poor control also reported more recent symptoms of depression, anxiety and hostility than did individuals in Moderate or Very Good control--symptomatology which may further impair their ability to adhere to a complex self-care regimen. Individuals with Long disease duration reported more positive and negative recent life experiences than did subjects with Short disease duration, but did not evidence concomitant disruptions in metabolic control. The role experience with a chronic disease may play in this finding was unclear, however. Although more research is required to clarify the exact relation of psychosocial variables and diabetic control, these findings suggest that clinically relevant subgroup parameters, subjects' perceptions of life change, and demographic variables may be important factors to assess. 相似文献
70.