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排序方式: 共有1478条查询结果,搜索用时 203 毫秒
1.
Luc Rochette Loubna Mazini Gabriel Malka Marianne Zeller Yves Cottin Catherine Vergely 《International journal of molecular sciences》2020,21(23)
The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs is a major goal in repair medicine. Stem cells are classified by their potential to differentiate into functional cells. Compared with other sources, adipose-derived stem cells (ADSCs) have the advantage of being abundant and easy to obtain. ADSCs are considered to be tools for replacing, repairing, and regenerating dead or damaged cells. The capacity of ADSCs to maintain their properties depends on the balance of complex signals in their microenvironment. Their properties and the associated outcomes are in part regulated by reactive oxygen species, which mediate the oxidation-reduction state of cells as a secondary messenger. ADSC therapy has demonstrated beneficial effects, suggesting that secreted factors may provide protection. There is evidence that ADSCs secrete a number of cytokines, growth factors, and antioxidant factors into their microenvironment, thus regulating intracellular signaling pathways in neighboring cells. In this review, we introduce the roles of ADSCs in the protection of cells by modulating inflammation and immunity, and we develop their potential therapeutic properties. 相似文献
2.
In this article, the authors study the factorial structure of 2 versions (64 items and 32 items) of the Dutch translation of the Inventory of Interpersonal Problems (IIP; L. M. Horowitz, L. E. Alden, J. S. Wiggins, & A. L. Pincus, 2000) in both a clinical sample (n = 382) and a student sample (n = 287). First, the authors test whether both inventories are constituted by correlated uni-dimensional subscales, and they conclude that this is true only for the short version. Second, the authors study whether the correlations between the subscales follow a circumplex pattern. This proves to be true for both versions. Coefficients alpha and correlations between the IIP-64 and IIP-32 subscales are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Jennifer G. Winter M. Catherine Eimers Peter J. Dillon Lem D. Scott Wolfgang A. Scheider Campbell C. Willox 《Journal of Great Lakes research》2007,33(2):381-396
Total phosphorus (TP) inputs to Lake Simcoe have led to hypolimnetic dissolved oxygen (DO) depletion and loss of cold water fish habitat. Since 1990, efforts have been made to reduce the total TP input to the lake below a defined target of 75 t/year, which was predicted to lead to reductions in spring TP concentration and improvements in end-of-summer hypolimnetic DO concentrations. The total TP load to the lake during the most recent period of record (1998/99-2003/04) ranged from 53 to 76 t/yr and averaged 67 t/yr, compared to an average of 114 t/yr estimated between 1990/91 and 1997/98 (range 85-157 t/yr). Reductions in TP loads from the catchment via tributary discharge (∼26 t) accounted for the majority of the decrease in total load between the two time periods. Total P concentrations decreased significantly in four out of six long-term monitored tributaries; however, concentrations in all six tributaries remain above the level recommended to avoid nuisance plant growth (30 μg/L). Although TP loads to the lake are currently below the target 75 t/yr, excessive growths of filamentous algae and macrophytes continue to be a problem in the nearshore zone. End-of-summer minimum hypolimnetic DO concentrations (average 4.3 mg/L, 1998/99-2003/04) remain substantially below the level (7 mg/L) that is considered protective of lake trout. Efforts to reduce TP loads to the lake therefore need to continue. 相似文献
4.
A computer model was extended and adapted to simulate the hygrothermal behavior of building envelope-wood components. The model was used to predict moisture movement in wood planks forming the decks of nonvented flat roofs insulated with cellulose. The gradient of water potential was considered as the driving force for moisture movement in wood. The model required the determination of convective heat- and mass-transfer coefficients, the sorption curves, the effective water conductivity for different wood species, and the hygrothermal conditions within the assembly to characterize the mass-conservation equation. Once these parameters were integrated in the computer model, this approach was then validated by carrying a simulation of the drying process of wood planks using experimental data from a large-scale test. 相似文献
5.
Vallerand Robert J.; Blais Marc R.; Lacouture Yves; Deci Edward L. 《Canadian Metallurgical Quarterly》1987,19(1):1
Conducted a reliability and validity study of the French version of E. L. Deci and R. M. Ryan's (1985) General Causality Orientations Scale (GCOS), which measures the extent to which people are oriented toward the autonomy, control, and impersonal aspects of the initiation and regulation of behavior. Findings support the psychometric and construct validity of the French version of the GCOS; suggestions for its use in French-Canadian psychological research are discussed. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Surendra P. Verma Jean R. Philippot Bernard Bonnet Josette Sainte-Marie Yves Moschetto Donald F. H. Wallach 《Lipids》1985,20(12):890-896
Raman and resonance Raman spectra of plasma lipoproteins ± malondialdehyde were studied at concentrations which block the
normal receptor-mediated uptake by cells. The strong resonance Raman bands at about 1010, 1162 and 1530 cm−1, due to the presence of carotenoids in the lipoproteins, are envisaged as structural probes. High resolution resonance Raman
spectra of the 1500–1600 cm−1 region reveal multiple features suggesting the coexistence of several structural populations of β-carotene whose precise
assignment is complex. When plasma lipoproteins are reacted with malondialdehyde, a complex change occurs in the resonance
Raman banding of β-carotene in the 1500–1600 cm−1 region. Malonaldehyde (MDA) also modifies the acoustical region (70–200 cm−1 of low density lipoprotein (LDL) lipids. We suggest that malondialdehyde association with plasma lipoproteins alters the
lipid structure via apoprotein or apoprotein/lipid associations. 相似文献
7.
8.
Minimizing the number of tool switches on a flexible machine 总被引:5,自引:0,他引:5
Yves Crama Antoon W. J. Kolen Alwin G. Oerlemans Frits C. R. Spieksma 《International Journal of Flexible Manufacturing Systems》1994,6(1):33-54
This article analyzes a tool switching problem arising in certain flexible manufacturing environments. A batch of jobs have to be successively processed on a single flexible machine. Each job requires a subset of tools, which have to be placed in the tool magazine of the machine before the job can be processed. The tool magazine has a limited capacity, and, in general, the number of tools needed to produce all the jobs exceeds this capacity. Hence, it is sometimes necessary to change tools between two jobs in a sequence. The problem is then to determine a job sequence and an associated sequence of loadings for the tool magazine, such that the total number of tool switches is minimized. This problem has been previously considered by several authors; it is here revisited, both from a theoretical and from a computational viewpoint. Basic results concerning the computational complexity of the problem are established. Several heuristics are proposed for its solution, and their performance is computationally assessed. 相似文献
9.
10.
Erik Mannens Davy Van Deursen Rapha?l Troncy Silvia Pfeiffer Conrad Parker Yves Lafon Jack Jansen Michael Hausenblas Rik Van de Walle 《Multimedia Tools and Applications》2012,59(2):691-715
To make media resources a prime citizen on the Web, we have to go beyond simply replicating digital media files. The Web is based on hyperlinks between Web resources, and that includes hyperlinking out of resources (e.g., from a word or an image within a Web page) as well as hyperlinking into resources (e.g., fragment URIs into Web pages). To turn video and audio into hypervideo and hyperaudio, we need to enable hyperlinking into and out of them. The W3C Media Fragments Working Group is taking on the challenge to further embrace W3C??s mission to lead the World Wide Web to its full potential by developing a Media Fragment protocol and guidelines that ensure the long-term growth of the Web. The major contribution of this paper is the introduction of Media Fragments as a media-format independent, standard means of addressing media resources using URIs. Moreover, we explain how the HTTP protocol can be used and extended to serve Media Fragments and what the impact is for current Web-enabled media formats. 相似文献