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151.
A survey was undertaken to examine the impact of Medicare's Prospective Payment System (PPS) and other recent changes in the health care environment on providers' decisions regarding acquisition of high-cost technologic equipment. The survey group included 199 hospitals and freestanding imaging centers known to have acquired magnetic resonance (MR) imaging units, as well as a random sample of 400 hospitals whose acquisition decisions were unknown to the authors. Fifty-eight percent of the known adopters and 61% of the randomly selected hospitals responded to the survey. Nonadopters' decisions were dominated by economic considerations, including the high cost of MR imagers and concerns about Medicare's reimbursement policies. Competition and a desire to provide the highest quality of care are counterbalancing the retardant effects of PPS, however, and are stimulating widespread diffusion of MR imagers. 相似文献
152.
Synthesized and directly acquired spin-echo images were compared in order to assess the validity of magnetic resonance (MR) image synthesis as a method enabling retrospective formation of images by interactive manipulation of scan parameters. Synthetic images subjectively compared favorably in both accuracy and precision with acquired images when formed for the same values of echo (TE) and repetition times (TR) and for interpolated and extrapolated values of both TE and TR. Plots of synthetic and acquired signals within the same pixel sectors quantitatively showed comparable values for several regions of interest in the brain. Percent error and noise-normalized differences between acquired and synthetic images were tested as a quantitative measure of accuracy. Percent error was consistently less than 5% for brain parenchyma, and synthetic signals were accurate to within four times the noise level at acquisition. The apparent signal-to-noise ratio of synthetic images was comparable, superior, or inferior to similar acquired images, depending on the values of TE and TR. Total acquisition time required for synthetic formation of images for arbitrary values of TE and TR was equivalent to that of a single direct acquisition with a TR of 2,500 msec. 相似文献
153.
SA Koehler 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(12):1514-1519
155.
Predicting a local recurrence after breast-conserving therapy by gene expression profiling
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Nuyten DS Kreike B Hart AA Chi JT Sneddon JB Wessels LF Peterse HJ Bartelink H Brown PO Chang HY van de Vijver MJ 《Breast cancer research : BCR》2006,8(5):R62-11
Introduction
To tailor local treatment in breast cancer patients there is a need for predicting ipsilateral recurrences after breast-conserving therapy. After adequate treatment (excision with free margins and radiotherapy), young age and incompletely excised extensive intraductal component are predictors for local recurrence, but many local recurrences can still not be predicted. Here we have used gene expression profiling by microarray analysis to identify gene expression profiles that can help to predict local recurrence in individual patients.Methods
By using previously established gene expression profiles with proven value in predicting metastasis-free and overall survival (wound-response signature, 70-gene prognosis profile and hypoxia-induced profile) and training towards an optimal prediction of local recurrences in a training series, we establish a classifier for local recurrence after breast-conserving therapy.Results
Validation of the different gene lists shows that the wound-response signature is able to separate patients with a high (29%) or low (5%) risk of a local recurrence at 10 years (sensitivity 87.5%, specificity 75%). In multivariable analysis the classifier is an independent predictor for local recurrence.Conclusion
Our findings indicate that gene expression profiling can identify subgroups of patients at increased risk of developing a local recurrence after breast-conserving therapy. 相似文献156.
Youth risk behavior surveillance--United States, 2005 总被引:3,自引:0,他引:3
Eaton DK Kann L Kinchen S Ross J Hawkins J Harris WA Lowry R McManus T Chyen D Shanklin S Lim C Grunbaum JA Wechsler H 《The Journal of school health》2006,76(7):353-372
In the United States, 71% of all deaths among persons aged 10-24 years result from 4 causes: motorvehicle crashes, other unintentional injuries, homicide, and suicide. Results from the 2005 national Youth Risk Behavior Survey (YRBS) indicated that during the 30 days preceding the survey, many high school students engaged in behaviors that increased their likelihood of death from these 4 causes: 9.9% had driven a car or other vehicle when they had been drinking alcohol, 18.5% had carried a weapon, 43.3% had drunk alcohol, and 20.2% had used marijuana. In addition, during the 12 months preceding the survey, 35.9% of high school students had been in a physical fight and 8.4% had attempted suicide. Substantial morbidity and social problems among youth also result from unintended pregnancies and sexually transmitted diseases, including human immunodeficiency virus infection. During 2005, a total of 46.8% of high school students had ever had sexual intercourse, 37.2% of sexually active high school students had not used a condom at last sexual intercourse, and 2.1% had ever injected an illegal drug. Among adults aged > or =25 years, 61% of all deaths result from 2 causes: cardiovascular disease and cancer. Results from the 2005 national YRBS indicated that risk behaviors associated with these 2 causes of death were initiated during adolescence. During 2005, a total of 23.0% of high school students had smoked cigarettes during the 30 days preceding the survey, 79.9% had not eaten > or =5 times/day of fruits and vegetables during the 7 days preceding the survey, 67.0% did not attend physical education classes daily, and 13.1% were overweight. 相似文献
157.
158.
Nygaard I Girts T Fultz NH Kinchen K Pohl G Sternfeld B 《Obstetrics and gynecology》2005,106(2):307-314
OBJECTIVE: To describe the prevalence of urinary incontinence during exercise in women, estimate whether exercise intensity is related to leakage severity, and report women's assessments of incontinence as a barrier to exercise. METHODS: Questionnaires were mailed to 5,130 women aged 18-60 years drawn from National Family Opinion research panels. Physical activity levels were assessed by the International Physical Activity Questionnaire. Urinary incontinence, defined as involuntary leakage in the last 30 days, was assessed with the Sandvik Severity Index and a global measure of bother. Prevalence estimates were adjusted via post-stratification weighting. RESULTS: A total of 3,364 eligible women responded (68%), of whom 34.6% were insufficiently active (95% confidence interval [CI] 32.7-36.5%), 29.7% were sufficiently active (95% CI 27.9-31.5%), and 35.7% were highly active (95% CI 33.8-37.6%). Urinary incontinence prevalence was 34.3% (95% CI 32.5-36.1%). One in seven women experienced urinary leakage during physical activity; this was more common among highly active (15.9%) than less active women (11.8%) (P = .01). After adjusting for age, comorbidities, education, and race, women with very severe incontinence were 2.64 times (95% CI 1.25-5.55) more likely to be insufficiently active than continent women. Incontinence was a moderate or substantial barrier to exercise for 9.8% (95% CI 8.8-10.9%) of women. Of incontinent women, the proportion for whom incontinence was a moderate or substantial barrier to exercise increased with each severity category: 9.2%, slight; 37.8%, moderate; 64.6%, severe; and 85.3%, very severe (P < .01). CONCLUSION: Urinary incontinence is perceived as a barrier to exercise, particularly by women with more severe leakage. 相似文献
159.
160.