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141.
Reactive oxygen intermediates (ROI) and nitric oxide (NO(.)) are produced in abundance in the inflammatory muscle diseases of autoimmune origin polymyositis (PM), dermatomyositis (DM), and inclusion body myositis (IBM). However, their role in the pathogenesis of these diseases is so far not clear. In contrast to demyelinating neuropathies, there is no convincing evidence for oxide-induced apoptosis either in myocytes or in lymphocytes and phagocytes in inflammatory myopathies. On the contrary, NO(.) released at low concentrations at target sites may even have cell-protective effects. A major mechanism of protection from apoptosis in both myocytes and inflammatory cells seems to be the upregulation of anti-apoptotic proteins like Bcl-2. Caution is warranted to apply antioxidative and anti-apoptotic agents to patients with inflammatory myopathies as long as the pathogenic role of oxides and apoptosis in the individual case is not resolved. 相似文献
142.
Back M. Gold R. Balsamo A. Chow M. Gorbet M. Harrison S. MacDonald D. Minnerman S. 《Computer》2001,34(1):80-87
Rather than eliminating reading as many fear, digital technology actually facilitates a wide array of exciting and unusual reading experiences. A research team at Xerox PARC has created a museum exhibition called XFR that provides a glimpse into the future of reading forms and how we will interact with them. The exhibit stimulates an awareness of the ubiquity of reading and its continued importance in the digital age. It also explores the range of exciting reading experiences made possible by new technology, from interactive readers to large-scale reading walls to dynamic narratives that change in response to reader input. Because the XFR show took place within the context of a modern technology museum, most of the exhibits are interactive and hands-on 相似文献
143.
Akhilesh K. Gaharwar Lauren M. Cross Charles W. Peak Karli Gold James K. Carrow Anna Brokesh Kanwar Abhay Singh 《Advanced materials (Deerfield Beach, Fla.)》2019,31(23)
Clay nanomaterials are an emerging class of 2D biomaterials of interest due to their atomically thin layered structure, charged characteristics, and well‐defined composition. Synthetic nanoclays are plate‐like polyions composed of simple or complex salts of silicic acids with a heterogeneous charge distribution and patchy interactions. Due to their biocompatible characteristics, unique shape, high surface‐to‐volume ratio, and charge, nanoclays are investigated for various biomedical applications. Here, a critical overview of the physical, chemical, and physiological interactions of nanoclay with biological moieties, including cells, proteins, and polymers, is provided. The state‐of‐the‐art biomedical applications of 2D nanoclay in regenerative medicine, therapeutic delivery, and additive manufacturing are reviewed. In addition, recent developments that are shaping this emerging field are discussed and promising new research directions for 2D nanoclay‐based biomaterials are identified. 相似文献
144.
微机测控技术在干式变压器试验中的应用 总被引:1,自引:0,他引:1
概述了干式变压器微机测试系统的特点,着重介绍了该系统在损耗试验和感应耐压试验中的应用情况。 相似文献
145.
Karen Jacobs Peter Johnson Denise Peterson Joshua Gold Nancy Richmond Emily Firn Sarah Hudak Victoria Hall Michael Pencina 《Applied ergonomics》2009,40(3):404-409
Recent evidence suggests that university students are self-reporting experiencing musculoskeletal discomfort with computer use similar to levels reported by adult workers. The objective of this study was to determine how university students use notebook computers and to determine what ergonomic strategies might be effective in reducing self-reported musculoskeletal discomfort in this population. Two hundred and eighty-nine university students randomly assigned to one of three towers by the university's Office of Housing participated in this study. The results of this investigation showed a significant reduction in self-reported notebook computer-related discomfort from pre- and post-survey in participants who received notebook computer accessories and in those who received accessories and participatory ergonomics training. A significant increase in post-survey rest breaks was seen. There was a significant correlation between self-reported computer usage and the amount measured using computer usage software (odometer). More research is needed however to determine the most effective ergonomics intervention for university students. 相似文献
146.
INTRODUCTION: The literature is sparse on reproducibility of self-reported exposure to physical ergonomics risk factors for musculoskeletal disorders (MSDs). Aims of this study were to evaluate, in a cohort of workers interviewed up to three times: 1-year test-retest reliability; and 5- and 6-year recall of physical exposures. We also examined whether reproducibility was influenced by the presence of UE MSD or by technological changes introduced between the last two surveys. METHODS: A cohort of automobile manufacturing employees was interviewed at baseline, one and six years later about work history, physical and psychosocial exposures at work, upper limb symptoms, injury and medical history, and demographics. Agreement between interviews was evaluated by intraclass correlation and Spearman coefficients. Differences in exposure between 1- and 6-year follow-up were analyzed by Wilcoxon matched-pairs signed-ranks test. RESULTS: Large and significant decreases in work pace and physical effort were observed from baseline, although an upper extremity composite index was quite stable in the total population. One-year test-retest reliability was fair to good for the composite exposure index (ICC=0.58), whole-body vibration, handling parts, and tool use, but poor for the other variables considered. Long-term reproducibility, from baseline or 1-year follow-up to 6-year follow-up, was poor for the composite index and almost all single items. UE MSD case status influenced 1-year test-retest reliability, with subjects who changed case status from baseline displaying higher reliability, but not reproducibility of recalled exposures. A strong regression to the mean effect was observed on exposures reported at follow-up surveys. CONCLUSIONS: Recalled ergonomics exposures could be employed in retrospective cohort studies as a somewhat reliable and unbiased estimate of the self-reported exposures that would have been obtained up to one year earlier, but not over a longer period (5-6 years). These longer-term results may have been limited by difficulty in matching jobs between interviews; also the regression to the mean effect likely contributed to reduce agreement. Changes in production technology and work organization produced a decrease in physical workload intensity and job pace, but did not have a substantial impact on an exposure index for the upper limb. 相似文献
147.
Gold B.T. Kim J. Smolens J.C. Chung E.S. Liaskovitis V. Nurvitadhi E. Falsafi B. Hoe J.C. Nowatzyk A.G. 《Micro, IEEE》2005,25(6):51-59
Traditional techniques that mainframes use to increase reliability -special hardware or custom software - are incompatible with commodity server requirements. The Total Reliability Using Scalable Servers (TRUSS) architecture, developed at Carnegie Mellon, aims to bring reliability to commodity servers. TRUSS features a distributed shared-memory (DSM) multiprocessor that incorporates computation and memory storage redundancy to detect and recover from any single point of transient or permanent failure. Because its underlying DSM architecture presents the familiar shared-memory programming model, TRUSS requires no changes to existing applications and only minor modifications to the operating system to support error recovery. 相似文献
148.
149.
Vidarsson L. Cunningham C. Gold G.E. Pauly J.M. 《IEEE transactions on medical imaging》2007,26(7):981-989
The purpose of this work was to present and evaluate a new method for directly designing T2-selective preparation pulses. Using a modified Shinnar-Le-Roux (SLR) transform, the design of T2-selective pulses becomes equivalent to designing a pair of polynomials one of which represents the longitudinal magnetization and the other the transverse magnetization. The polynomials enable one to directly analyze the various tradeoffs involved in the design. To evaluate the new method, a short-T2-selective magnetization preparation pulse was designed. Following the preparation pulse, a 2D Fourier transform (2DFT) multislice gradient echo sequence was used for imaging. For verification Bloch equation simulations were performed along with both in vivo and phantom scans. Phantom scans showed good signal suppression of long-T2 species. This is supported by good long-T2 signal suppression seen on the in vivo images. Simulations indicate that the pulse is robust to plusmn150 Hz B0 inhomogeneities and plusmn10% B1 inhomogeneities. 相似文献
150.
Garret Nelson Jeffrey Ross Candace M. Prusiewicz Ramiah Sangaiah Avram Gold 《Polycyclic Aromatic Compounds》2013,33(3-4):923-931
Four major and several minor DNA adducts were resolved by 32 P-postlabeling analysis of DNA from strain A/J mouse lung and C3H10T1/2CL8 (C3H10T1/2) mouse embryo fibroblasts treated with cyclopenta[ cd ]pyrene (CPP). The identical pattern of adducts was seen in vivo and in vitro. Cochromatography of synthetic resolved diastereomers of cis - and trans - N 2 -CPP-deoxyguanosine-3'-phosphates with the in vivo adducts obtained from strain A/J mouse lung and in vitro adducts obtained from C3H10T1/2 cells allowed identification of the predominant DNA adduct as cis -(3 R ,4 S )- N 2 -CPP-deoxyguanosine. The second most abundant adduct formed in vivo and in vitro was identified as trans -(3 S ,4 S )- N 2 -CPP-deoxyguanosine. 相似文献