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排序方式: 共有1613条查询结果,搜索用时 0 毫秒
81.
设计性能出色的全新3D电视可走终南捷径,赛灵思介绍了其Spartan-6 FPGA消费显示套件和IP,可为DisplayPort设计带来方便. 相似文献
82.
Diagnosing diabetic nephropathy by 1H NMR metabonomics of serum 总被引:2,自引:0,他引:2
Mäkinen VP Soininen P Forsblom C Parkkonen M Ingman P Kaski K Groop PH Ala-Korpela M;FinnDiane Study Group 《Magma (New York, N.Y.)》2006,19(6):281-296
Object: The most severe complication of type 1 diabetes (T1DM) is diabetic nephropathy. It is associated with a high risk of cardiovascular
complications and premature death and requires early detection to be efficiently treated. The clinical practice to diagnose
diabetic nephropathy is also a non-optimal and tedious set up based on albumin excretion rate in multiple overnight or 24h
urine samples. Conversely, in this study, these independent diagnostic data are used to provide a realistic testing case for
applying 1H NMR metabonomics of serum in a diagnostic fashion.
Materials and Methods: 182 T1DM and 21 non-diabetic (non-T1DM) individuals were studied. The 1H NMR of serum at 500 MHz was targeted at two molecular windows: lipoprotein lipids and low-molecular-weight metabolites.
Results: T1DM and non-T1DM individuals were exclusively separated by 1H NMR. For diabetic nephropathy diagnosis in the T1DM patients, 1H NMR data (and clinical biochemistry data) gave a sensitivity of 87.1% (83.9%) and a specificity of 87.7% (95.9%). The predictive
values of positive and negative tests were 89.0% (95.5%) and 83.6% (79.2%), respectively.
Conclusions: 1H NMR metabonomics clearly distinguishes metabolic characteristics of T1DM and appears approximately as good a means to diagnose
diabetic nephropathy from serum as an advanced set of biochemical variables. 相似文献
83.
Samuel J. Bunce Yiming Wang Sheena E. Radford Andrew J. Wilson Carol K. Hall 《American Institute of Chemical Engineers》2021,67(3):e17101
Determining the structure of the (oligomeric) intermediates that form during the self-assembly of amyloidogenic peptides is challenging because of their heterogeneous and dynamic nature. Thus, there is need for methodology to analyze the underlying molecular structure of these transient species. In this work, a combination of fluorescence quenching, photo-induced crosslinking (PIC) and molecular dynamics simulation was used to study the assembly of a synthetic amyloid-forming peptide, Aβ16-22. A PIC amino acid containing a trifluormethyldiazirine (TFMD) group—Fmoc(TFMD)Phe—was incorporated into the sequence (Aβ*16–22). Electrospray ionization ion-mobility spectrometry mass-spectrometry (ESI-IMS-MS) analysis of the PIC products confirmed that Aβ*16–22 forms assemblies with the monomers arranged as anti-parallel, in-register β-strands at all time points during the aggregation assay. The assembly process was also monitored separately using fluorescence quenching to profile the fibril assembly reaction. The molecular picture resulting from discontinuous molecule dynamics simulations showed that Aβ16-22 assembles through a single-step nucleation into a β-sheet fibril in agreement with these experimental observations. This study provides detailed structural insights into the Aβ16-22 self-assembly processes, paving the way to explore the self-assembly mechanism of larger, more complex peptides, including those whose aggregation is responsible for human disease. 相似文献
84.
Ian Mabbett Jon Elvins Catherine Gowenlock Carol Glover Paul Jones Geraint Williams David Worsley 《Progress in Organic Coatings》2014
Near infrared (NIR) is becoming a popular option for rapid cure of coatings in the coil coating industry particularly where fast line speeds are required. The technology has the potential to reduce the cure time of a 20 μm polyester coating on a galvanised steel substrate from around 30 s via conventional heating methods down to <10 s under the lamps. Previous work suggested that the ideal situation in this case is to have a topcoat which is slightly transparent to NIR and an absorbing substrate to heat the coating from the substrate outwards in a two stage process which separates solvent removal from cross linking and film formation. This can be taken further by tinting the primer layer with a pigment that absorbs in the NIR region. In this study spectroscopy was used to show that a coated steel system could appear white in the visible region because of the reflectance of TiO2 but the NIR absorption could be altered by adding absorbing pigments such as carbon black. Lamp settings could be reduced by 20% to achieve equivalent cure with tinted primer systems. The potential degradation in corrosion protection afforded by carbon-black containing pigments at various loadings was assessed for model organic coatings applied to galvanised steel specimens. In situ scanning Kelvin probe studies showed that rates of corrosion-driven coating delamination by cathodic disbondment remained unchanged by pigment loadings of up to 3.5 wt%. 相似文献
85.
This study examined the contributions of four individual difference predictors to preschool children's recall for object names. Measures of object knowledge (the Peabody Picture Vocabulary Test [PPVT]), conceptual tempo (the Kansas Reflection-Impulsivity Scale for Preschoolers [KRISP] error scores), strategic study period activities, and teacher ratings of children's mastery motivation were used to predict recall scores of 3- and 4-year-old children. KRISP-error scores, strategic study activities, and motivation ratings were found to be significant correlates of recall. Motivation ratings entered a regression prediction equation first, followed by the strategic study activity measure, yielding a multiple correlation of .62. These predictors were unrelated, suggesting that motivational factors contributed to young children's recall proficiency directly, perhaps through greater task involvement and analysis and more effortful retrieval activity, and do not mediate strategic study behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Carol L. Haertling Shoko Yoshikawa Robert E. Newnham 《Journal of the American Ceramic Society》1990,73(11):3339-3344
Screen-printed layers of Al2 O3 , BaTiO3 , 0.90Pb(Mg1/3 Nb2/3 )-03 –0.10PbTiO3 , Pb(Zr,Ti)O3 , ZnO, and glass alumina pastes have been patterned using photoprinting techniques. Curability of each paste by ultraviolet light and formation of holes with various diameters were studied for application as a production method for very small-sized vias. The dependence of hole diameters on various experimental parameters is presented and discussed. Wall slopes were found to depend on the transmission of the powders used in the pastes. 相似文献
87.
Following a midterm exam in an introductory psychology course, college students (N?=?189) were administered the same test items under nonevaluative conditions. The hypothesis that high-anxious individuals as compared with low-anxious individuals would retrieve a greater degree of information not previously available to them when they were assessed under reduced threat was only partially supported. However, easy-item performance provided some evidence for an interference phenomenon. An interaction indicated that previously blocked information became available only for those high-anxious students who had initially used effective study strategies. Path analysis confirmed the relative importance of anxiety phenomena to classroom test performance in a time-ordered causal network involving ability level, study effectiveness, and anxiety arousal. Results add credence to a recent interpretation of anxiety as a failure-of-self phenomenon. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Mitchell Karen J.; Johnson Marcia K.; Raye Carol L.; Mather Mara; D'Esposito Mark 《Canadian Metallurgical Quarterly》2000,15(3):527
It was hypothesized that age-related deficits in episodic memory for feature combinations (e.g., B. L. Chalfonte & M. K. Johnson, 1996) signal, in part, decrements in the efficacy of reflective component processes (e.g., M. K. Johnson, 1992) that support the short-term maintenance and manipulation of information during encoding (e.g., F. I. M. Craik, R. G. Morris, & M. L. Gick, 1990; T. A. Salthouse, 1990). Consistent with this, age-related binding deficits in a working memory task were found in 2 experiments. Evidence for an age-related test load deficit was also found: Older adults had greater difficulty than young adults when tested on 2 features rather than 1, even when binding was not required. Thus, disruption of source memory in older adults may involve deficits in both encoding processes (binding deficits) and monitoring processes (difficulty accessing multiple features, evaluating them, or both). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
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