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991.
Manuel Garcia Ruiz Alvin Garcia Chaves Carlos Ruiz Iba?ez Jorge Mario Gutierrez Mazo Juan Carlos Ramirez Giraldo Alejandro Pelaez Echavarria Edison Valencia Diaz Gustavo Pelaez Restrepo Edwin Nelson Montoya Munera Bernardo Garcia Loaiza Sebastian Gomez Gonzalez 《Journal of digital imaging》2011,24(2):271-283
This paper presents the mantisGRID project, an interinstitutional initiative from Colombian medical and academic centers aiming to provide medical grid services for Colombia and Latin America. The mantisGRID is a GRID platform, based on open source grid infrastructure that provides the necessary services to access and exchange medical images and associated information following digital imaging and communications in medicine (DICOM) and health level 7 standards. The paper focuses first on the data abstraction architecture, which is achieved via Open Grid Services Architecture Data Access and Integration (OGSA-DAI) services and supported by the Globus Toolkit. The grid currently uses a 30-Mb bandwidth of the Colombian High Technology Academic Network, RENATA, connected to Internet 2. It also includes a discussion on the relational database created to handle the DICOM objects that were represented using Extensible Markup Language Schema documents, as well as other features implemented such as data security, user authentication, and patient confidentiality. Grid performance was tested using the three current operative nodes and the results demonstrated comparable query times between the mantisGRID (OGSA-DAI) and Distributed mySQL databases, especially for a large number of records. 相似文献
992.
Christopher Bell Lori D. McLeod Lauren M. Nelson Sheri E. Fehnel Laurie J. Zografos Brian Bowers 《Quality of life research》2011,20(9):1457-1468
Purpose
The objective of this study was to develop and validate a patient-reported outcome instrument to comprehensively assess the consequences of inadequate sleep for use in insomnia-related studies. 相似文献993.
994.
Redundant and Synergistic Mechanisms Control the Sequestration of Blood-born Adenovirus in the Liver
Human adenovirus (Ad) is a ubiquitous pathogen causing a wide range of diseases. Although the interactions of human Ad serotype 5 (Ad5) with susceptible cells in vitro are known in great detail, host factors controlling the tissue specificity of Ad5 infection in vivo remain poorly understood. Here, we analyzed the mechanisms of sequestration by the liver for blood-born human Ads and Ad5-based vectors. Our data suggest that several known mechanisms that lead to Ad5 sequestration by the liver become engaged in a redundant, sequential, and synergistic manner to ensure the rapid clearance of circulating virus particles from the blood. These mechanisms include (i) trapping of the virus by liver residential macrophages, Kupffer cells; (ii) Ad5 hepatocyte infection via blood factor–hexon interactions; and (iii) Ad5 penton RGD motif–mediated interactions with liver endothelial cells and hepatocytes, mediating virus retention in the space of Disse. More important, we show that when all of these mechanisms are simultaneously inactivated via mutations of Ad5 capsid proteins and pharmacological interventions, virus sequestration by the liver is markedly reduced. Therefore, our study is the first demonstration of the principal possibility of ablating the sequestration of blood-born Ad in the liver via specific inactivation of a defined set of mechanisms that control this process. 相似文献
995.
996.
Mandy A. Allison Ginger Guest-Warnick Douglas Nelson Andrew T. Pavia Rajendu Srivastava Per H. Gesteland Robert T. Rolfs Shannon Andersen Lynne Calame Paul Young Carrie L. Byington 《Influenza and other respiratory viruses》2010,4(4):223-229
Please cite this paper as: Allison et al. (2010) Feasibility of elementary school children’s use of hand gel and facemasks during influenza season. Influenza and Other Respiratory Viruses 4(4), 223–229. Background The feasibility of non-pharmacologic interventions to prevent influenza’s spread in schools is not well known. Objectives To determine the acceptability of, adherence with, and barriers to the use of hand gel and facemasks in elementary schools. Patients and Methods Intervention: We provided hand gel and facemasks to 20 teachers and their students over 4 weeks. Gel use was promoted for the first 2 weeks; mask use was promoted for the second 2 weeks. Outcomes: Acceptability, adherence, and barriers were measured by teachers’ responses on weekly surveys. Mask use was also measured by observation. Results The weekly survey response rate ranged from 70% to 100%. Averaged over 2 weeks, 89% of teachers thought gel use was not disruptive (week 1 – 17/20, week 2 – 16/17), 95% would use gel next winter (week 1 – 19/20, week 2 – 16/17), and 97% would use gel in a pandemic (week 1 – 20/20, week 2 – 16/17). Averaged over 2 weeks, 39% thought mask use was not disruptive (week 1 – 6/17, week 2 – 6/14), 35% would use masks next winter (week 1 – 5/17, week 2 – 6/14), and 97% would use masks in a pandemic (week 1 – 16/17, week 2 – 14/14). About 70% estimated that their students used hand gel ≥4×/day for both weeks (week 1 – 14/20, week 2 – 13/17). Students’ mask use declined over time with 59% of teachers (10/17) estimating regular mask use during week 1 and 29% (4/14) during week 2. By observation, 30% of students wore masks in week 1, while 15% wore masks in week 2. Few barriers to gel use were identified; barriers to mask use were difficulty reading facial expressions and physical discomfort. Conclusions Hand gel use is a feasible strategy in elementary schools. Acceptability and adherence with facemasks was low, but some students and teachers did use facemasks for 2 weeks, and most teachers would use masks in their classroom in a pandemic. 相似文献
997.
998.
Isabelle Iltis Dee M. Koski Lynn E. Eberly Christopher D. Nelson Dinesh K. Deelchand Julien Valette Kamil Ugurbil Kelvin O. Lim Pierre‐Gilles Henry 《NMR in biomedicine》2009,22(7):737-744
Acute phencyclidine (PCP) administration mimics some aspects of schizophrenia in rats, such as behavioral alterations, increased dopaminergic activity and prefrontal cortex dysfunction. In this study, we used single‐voxel 1H‐MRS to investigate neurochemical changes in rat prefrontal cortex in vivo before and after an acute injection of PCP. A short‐echo time sequence (STEAM) was used to acquire spectra in a 32‐µL voxel positioned in the prefrontal cortex area of 12 rats anesthetized with isoflurane. Data were acquired for 30 min before and for 140 min after a bolus of PCP (10 mg/kg, n = 6) or saline (n = 6). Metabolites were quantified with the LCModel. Time courses for 14 metabolites were obtained with a temporal resolution of 10 min. The glutamine/glutamate ratio was significantly increased after PCP injection (p < 0.0001, pre‐ vs. post‐injection), while the total concentration of these two metabolites remained constant. Glucose was transiently increased (+70%) while lactate decreased after the injection (both p < 0.0001). Lactate, but not glucose and glutamine, returned to baseline levels after 140 min. These results show that an acute injection of PCP leads to changes in glutamate and glutamine concentrations, similar to what has been observed in schizophrenic patients, and after ketamine administration in humans. MRS studies of this pharmacological rat model may be useful for assessing the effects of potential anti‐psychotic drugs in vivo. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
999.
Mandeep S. Sawhney Heather McDougall Douglas B. Nelson John H. Bond 《Digestive diseases and sciences》2010,55(6):1637-1642
Aim
To determine the effect of anticoagulants and antiplatelet medications on the positive-predictive-value of fecal occult blood test (FOBT). 相似文献1000.
Polly Hitchcock Noël Laurel A. Copeland Mary Jo Pugh Leila Kahwati Joel Tsevat Karin Nelson Chen-Pin Wang Mary J. Bollinger Helen P. Hazuda 《Journal of general internal medicine》2010,25(6):510-516