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991.
Given the current extensive reliance on the graphical user interface, independent access to computer software requires that users be able to manipulate a pointing device of some type (e.g., mouse, trackball) or be able to emulate a mouse by some other means (e.g., scanning). The purpose of the present study was to identify one or more optimal single-switch scanning mouse emulation strategies. Four alternative scanning strategies (continuous Cartesian, discrete Cartesian, rotational, and hybrid quadrant/continuous Cartesian) were selected for testing based on current market availability as well as on theoretical considerations of their potential speed and accuracy. Each strategy was evaluated using a repeated measures study design by means of a test program that permitted mouse emulation via any one of four scanning strategies in a motivating environment; response speed and accuracy could be automatically recorded and considered in view of the motor, cognitive, and perceptual demands of each scanning strategy. Ten individuals whose disabilities required them to operate a computer via single-switch scanning participated in the study. Results indicated that Cartesian scanning was the preferred and most effective scanning strategy. There were no significant differences between results from the Continuous Cartesian and Discrete Cartesian scanning strategies. Rotational scanning was quite slow with respect to the other strategies, although it was equally accurate. Hybrid Quadrant scanning improved access time but at the cost of fewer correct selections. These results demonstrated the importance of testing and comparing alternate single-switch scanning strategies.  相似文献   
992.
National Patient Safety Goals guide safe care   总被引:4,自引:0,他引:4  
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993.
The final moments of a life pose a special and very important time for all participants. Sensitive arrangement of events can provide harmony and a peaceful and memorable transition event. A specific situation, in which a feather is used to symbolize the transition, is reported. Hospice programs can offer ecologically based celebration of life and provide a positive transition for patients, families, friends, and staff.  相似文献   
994.
The Health Belief Model (HBM) was reviewed with the aim of modifying it so that it reflected a health promotion stance for young families. Since this model's inception, health professionals like nurses have been involved in using the HBM to guide their practice. It is argued that to assist families, nurses now need a model that is focused on "health." In support of this approach, reorienting the HBM and basing it on "positive" health definitions associated with health promotion, by modifying it through adding the constructs "perceived behavioral control" (representing health locus of control) and "behavioral intention" from Ajzen will provide nurses with a more appropriate and useful model for interacting with families and their preschool children. A summary of positive and negative aspects of the modification of the HBM is presented, followed by a strategy for the process of validating the revised HBM for young families.  相似文献   
995.
Mechanisms and evidence for the role of nutrition in cognitive ageing   总被引:1,自引:0,他引:1  
This review examines the mechanisms and empirical evidence from epidemiological and experimental studies for the role of the B vitamins folate and vitamins B-12 and B-6, antioxidants, omega 3 polyunsaturated fatty acids (PUFAs) and the popular herbal supplement, Ginkgo biloba in the maintenance and enhancement of cognitive performance in older adults. Although there are plausible mechanisms by which these dietary components could affect cognition, these hypothesized effects are yet to be clearly substantiated. As the effects of dietary components on cognitive performance are likely to be subtle, methodological issues such as appropriate outcome measures and adequate sample sizes need careful consideration. Janet Bryan, Ph.D., holds an academic position at University of South Austalia. Her major research interest is in cognitive change across the life-span. For the last five years she has investigated the role of nutrition and other lifestyle factors in the cognitive development and cognitive change of children and adults.  相似文献   
996.
BACKGROUND: Previous studies suggest that intraoperative anesthetic care may influence postoperative pain and recovery from surgery. The authors tested the hypothesis that the addition of intrathecal analgesia to general anesthesia would improve long-term functional status and decrease pain in patients undergoing radical retropubic prostatectomy. METHODS: One hundred patients received either general anesthesia supplemented with intravenous fentanyl or general anesthesia preceded by intrathecal administration of bupivacaine (15 mg), clonidine (75 microg), and morphine (0.2 mg). Patients and providers were masked to treatment assignment. All patients received multimodal pain management postoperatively. Primary outcomes included pain and functional status over the first 12 postoperative weeks. RESULTS: Patients receiving intrathecal analgesia required more intravenous fluids and vasopressors intraoperatively. Pain was well controlled throughout the study (mean numerical pain scores < 3 in both groups at all times studied). Intrathecal analgesia decreased pain and supplemental intravenous morphine use over the first postoperative day but increased the frequency of pruritus. Pain and functional status after discharge from the hospital did not differ between groups. Intrathecal analgesia significantly decreased the duration of hospital stay (from 2.8 +/- 2.0 to 2.1 +/- 0.5 days; P < 0.01) as a result of five patients in the control group who stayed in the hospital more than 3 days. CONCLUSIONS: The benefits of improved immediate analgesia and decreased morphine requirements resulting from intrathecal analgesia must be weighed against factors such as pruritus, increased intraoperative requirement for fluids and vasopressors, and resources needed to implement this modality. Further studies are needed to determine the significance of the decrease in duration of hospital stay.  相似文献   
997.
998.
The aims of this study were to assess the potential of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) for tumor grading in chondrosarcoma patients and to evaluate the role of standardized uptake value (SUV) as a parameter for prediction of patient outcome. FDG PET imaging was performed in 31 patients with chondrosarcoma prior to therapy. SUV was calculated for each tumor and correlated to tumor grade and size, and to patient outcome in terms of local relapse or metastatic disease with a mean follow-up period of 48 months. Chondrosarcomas were detectable in all patients. Tumor SUV was 3.38±1.61 for grade I (n=15), 5.44±3.06 for grade II (n=13), and 7.10±2.61 for grade III (n=3). Significant differences were found between patients with and without disease progression: SUV was 6.42±2.70 (n=10) in patients developing recurrent or metastatic disease compared with 3.74±2.22 in patients without relapse (P=0.015). Using a cut-off of 4 for SUV, sensitivity, specificity, and positive and negative predictive values for a relapse were 90%, 76%, 64%, and 94%, respectively. Combining tumor grade and SUV, these parameters improved to 90%, 95%, 90%, and 95%, respectively. Pretherapeutic tumor SUV obtained by FDG PET imaging was a useful parameter for tumor grading and prediction of outcome in chondrosarcoma patients. The combination of SUV and histopathologic tumor grade further improved prediction of outcome substantially, allowing identification of patients at high risk for local relapse or metastatic disease.  相似文献   
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