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Afnan M. Alkhateeb Bonnie J. Forrester Noha S. Daher Bradford D. Martin Asma A. Alonazi 《Assistive technology : the official journal of RESNA》2017,29(4):210-216
People in wheelchairs spend a long time in the sitting position and often incur alignment problems resulting in neck and back pain. This study: (1) assessed the validity/reliability of Coach’s Eye (CE) smart device application, (2) examined the effect of seat to back support angle adjustments on head, neck, and shoulder posture in the sitting position, and (3) compared changes in cervical rotation at each back support angle. Abled subjects sat in a wheelchair with back support angles positioned at 90°, 100°, and 110°. CE, as well as ImageJ software, was used to analyze three angles: sagittal head angle (SHA), cervical angle (CVA), and shoulder angle (SA). There were highly significant differences for CVA and SA (p < 0.001) among the three seat to back support angles. Validity of CE was examined by correlating CE with ImageJ scores. CE had high validity for all angles (r = 0.99, 0.98, 0.99 respectively, p < 0.001). Inter-rater reliability for SHA, CVA, and SA was high (intraclass correlation coefficient [ICC] ranged from 0.95 to 0.99). Head (CVA) and shoulder (SA) alignment was closest to neutral posture with back support angles set at 110° and 90°, respectively. 相似文献
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Separation of the Messenger RNAs of Newcastle Disease Virus by Gel Electrophoresis 总被引:13,自引:1,他引:13 下载免费PDF全文
Bonnie Spanier Collins Michael A. Bratt 《Proceedings of the National Academy of Sciences of the United States of America》1973,70(9):2544-2548
We have separated the 18-22S putative messenger RNA of Newcastle disease virus into seven species ranging in molecular weight from 0.55 to 1.53 x 10(6) using sodium dodecyl sulfate-acrylamide-gel electrophoresis at relatively high concentrations of acrylamide and for a relatively long time. Studies of the number and molecular weights of the proteins and the 18-22S RNAs of the virus suggests that these RNAs are in the right molecular weight range to code for the known proteins of Newcastle disease virus. In preliminary studies using this separation technique, we have demonstrated that: (a) there is no difference between the 18-22S RNA made during a normal infection and when genome replication is blocked; and (b) there is a strain-specific difference between the RNAs of Newcastle disease virus-AV and Newcastle disease virus-HP. 相似文献
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Shannon C. Wieland Christopher A. Cassa Kenneth D. Mandl Bonnie Berger 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(46):17608-17613
Datasets describing the health status of individuals are important for medical research but must be used cautiously to protect patient privacy. For patient data containing geographical identifiers, the conventional solution is to aggregate the data by large areas. This method often preserves privacy but suffers from substantial information loss, which degrades the quality of subsequent disease mapping or cluster detection studies. Other heuristic methods for de-identifying spatial patient information do not quantify the risk to individual privacy. We develop an optimal method based on linear programming to add noise to individual locations that preserves the distribution of a disease. The method ensures a small, quantitative risk of individual re-identification. Because the amount of noise added is minimal for the desired degree of privacy protection, the de-identified set is ideal for spatial epidemiological studies. We apply the method to patients in New York County, New York, showing that privacy is guaranteed while moving patients 25—150 times less than aggregation by zip code. 相似文献
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Tricuspid valve dysfunction occurs frequently in patients with rheumatic heart disease and is usually manifested as functional or organic tricuspid regurgitation. Rheumatic tricuspid stenosis is less common and occurs characteristically in the presence of concomitant mitral valve disease. In this report, we describe the clinical and echocardiographic findings in a patient with isolated rheumatic tricuspid stenosis and a right-to-left shunt across the interatrial septum, likely as a result of a patent foramen ovale, resulting in central cyanosis. This case illustrates an interesting association of tricuspid stenosis and an interatrial right-to-left shunt suggestive of a reverse Lutembacher's physiology. 相似文献
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