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51.
F Wolfe M Lassere D van der Heijde G Stucki M Suarez-Almazor T Pincus K Eberhardt TK Kvien D Symmons A Silman P van Riel P Tugwell M Boers 《Canadian Metallurgical Quarterly》1999,26(2):484-489
The minimized energy mapping of annexin V Trp-187 chi1 x chi2 isomerization supports the existence of two preferential rotameric orientations of the Trp side chain upon annexin V binding to membranes, in agreement with the time-resolved fluorescence results. They correspond to the perpendicular trans (-173 degrees, 73 degrees) and g- (-71 degrees, 83 degrees) rotamers and represent 59 and 28% of the population, respectively. The analysis of their local environment makes it possible to assign the trans rotamer to the long component and the g- rotamer to the short component of the biexponential fluorescence decay. The orientation of these rotamers relative to the protein core suggests a dual role for Trp-187, which might be involved both in the interaction with the phospholipid bilayer and in the formation of the annexin V 2-D array at the surface of the membrane. 相似文献
52.
Wolfe R.H. Needels M. Arias T. Joannopoulos J.D. 《Computer Graphics and Applications, IEEE》1992,12(4):45-53
The use of volumetric rendering for interpreting the computed electronic structure of solids is discussed. The structure, manifested as an atomic-scale 3-D electronic charge density, is computed from a pure mathematical model. The mathematical technique represents a class of ab initio computations that predict the atomic structure by solving the equations of quantum mechanics, wherein all configuration parameters except the atomic number are under the analyst's control. Some physics aspects of electronic structure of solids are reviewed. The use of this visualization technique to interpret the computations for silicon with an oxygen impurity and for room-temperature silicon is described 相似文献
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Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States 总被引:3,自引:0,他引:3
RC Lawrence CG Helmick FC Arnett RA Deyo DT Felson EH Giannini SP Heyse R Hirsch MC Hochberg GG Hunder MH Liang SR Pillemer VD Steen F Wolfe 《Canadian Metallurgical Quarterly》1998,41(5):778-799
OBJECTIVE: To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS: The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS: Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION: Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population. 相似文献
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Chang C.-I. Wolfe L.B. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1992,38(4):1391-1395
The source matching problem is to find the minimax codes that minimize the maximum redundancies over classes of sources where relative entropy (cross entropy, discrimination information) is adopted as a criterion to measure the redundancy. The convergence of a simple approach different from L.D. Davisson and A. Leon-Garcia's (1980) algorithm for finding such minimax codes is presented and shown. This approach is applied as an example to the class of first-order discrete Markov sources. The sufficient statistic previously used by D.H. Lee (1983) in his attempt to produce results for the first-order Markov source matching problem is corrected. A computational complexity analysis and a numerical study further demonstrate that this simple algorithm significantly reduces the required computing time, when compared to Davisson and Leon-Garcia's algorithm 相似文献
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ME Klepser EJ Wolfe RN Jones CH Nightingale MA Pfaller 《Canadian Metallurgical Quarterly》1997,41(6):1392-1395
Time-kill curves were determined for three isolates of Candida albicans tested against fluconazole and amphotericin B at multiples of the MIC. Fluconazole produced fungistatic activity, with concentration-related growth effects observed over a narrow range of concentrations. Amphotericin B exhibited fungicidal activity, with enhancement of activity over a broader range of concentrations. 相似文献
59.
Wolfe David A.; Wekerle Christine; Scott Katreena; Straatman Anna-Lee; Grasley Carolyn; Reitzel-Jaffe Deborah 《Canadian Metallurgical Quarterly》2003,71(2):279
This study evaluated a community-based intervention to help at-risk teens develop healthy, nonabusive relationships with dating partners. Participants were 158 14-16-year-olds with histories of child maltreatment who were randomly assigned to a preventive intervention group or a no-treatment control group. They completed measures of abuse and victimization with dating partners, emotional distress, and healthy relationship skills at bimonthly intervals when dating someone. Intervention consisted of education about healthy and abusive relationships, conflict resolution and communication skills, and social action activities. Growth curve analyses showed that intervention was effective in reducing incidents of physical and emotional abuse and symptoms of emotional distress over time. Findings support involvement of youths in reducing the cycle of violence as they initiate dating in midadolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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