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排序方式: 共有184条查询结果,搜索用时 15 毫秒
61.
Oana Dobre Mariana A. G. Oliva Giuseppe Ciccone Sara Trujillo Aleixandre Rodrigo-Navarro Douglas Cormac Venters Virginia Llopis-Hernandez Massimo Vassalli Cristina Gonzalez-Garcia Matthew J. Dalby Manuel Salmeron-Sanchez 《Advanced functional materials》2021,31(21):2010225
Laminins (LMs) are important structural proteins of the extracellular matrix (ECM). The abundance of every LM isoform is tissue-dependent, suggesting that LM has tissue-specific roles. LM binds growth factors (GFs), which are powerful cytokines widely used in tissue engineering due to their ability to control stem cell differentiation. Currently, the most commonly used ECM mimetic material in vitro is Matrigel, a matrix of undefined composition containing LM and various GFs, but subjected to batch variability and lacking control of physicochemical properties. Inspired by Matrigel, a new and completely defined hydrogel platform based on hybrid LM-poly(ethylene glycol) (PEG) hydrogels with controllable stiffness (1–25 kPa) and degradability is proposed. Different LM isoforms are used to bind and efficiently display GFs (here, bone morphogenetic protein (BMP-2) and beta-nerve growth factor (β-NGF)), enabling their solid-phase presentation at ultralow doses to specifically target a range of tissues. The potential of this platform to trigger stem cell differentiation toward osteogenic lineages and stimulate neural cells growth in 3D, is demonstrated. These hydrogels enable 3D, synthetic, defined composition, and reproducible cell culture microenvironments reflecting the complexity of the native ECM, where GFs in combination with LM isoforms yield the full diversity of cellular processes. 相似文献
62.
63.
María-Luisa Rapún Francisco-Javier Sayas 《Archives of Computational Methods in Engineering》2007,14(1):3-46
In this paper we survey computational techniques based on boundary integral formulations for the simulation of thermal waves.
Time-harmonic solutions to diffusion problems appear in many physical situations of interest and give rise to many interesting
problems related to material characterization, parameter assessment or detection of defects. We review the main direct, indirect
and mixed integral numerical methods for a model of scattering of thermal waves by many obstacles and discuss how multiple
scattering techniques and other physical tools can be understood as iterative methods or used as preconditioners. We also
deal with some transient problems that can be solved with boundary element methods using the Laplace transform and with coupled
finite and boundary element schemes for non-homogeneous obstacles. 相似文献
64.
The formation of nickel silicides and vanadium silicides and the diffusion barrier effect of a vanadium layer in the formation of nickel silicides were studied for annealed metal films deposited on silicon substrates by depth profiling using secondary ion mass spectrometry and X-ray diffraction. Nickel films more than 2500 Å thick react with silicon after annealing at 400 °C for 30 min in a vacuum. A vanadium layer 250 Å thick between nickel and silicon shows a barrier effect in the nickel silicide formation after annealing at 400 °C for 30 min. The barrier effect of a vanadium layer 250 Å thick becomes imperfect after annealing at 500 °C for 30 min. 相似文献
65.
Lavinia-Lorena Pruteanu Cornelia Braicu Dezs Mdos Maria-Ancua Jurj Lajos-Zsolt Raduly Oana Znoag Lorand Magdo Roxana Cojocneanu Sergiu Paca Cristian Moldovan Alin Iulian Moldovan Adrian Bogdan igu Eugen Gurzu Lorentz Jntschi Andreas Bender Ioana Berindan-Neagoe 《International journal of molecular sciences》2022,23(9)
Triple negative breast cancer (TNBC) is currently associated with a lack of treatment options. Arsenic derivatives have shown antitumoral activity both in vitro and in vivo; however, their mode of action is not completely understood. In this work we evaluate the response to arsenate of the double positive MCF-7 breast cancer cell line as well as of two different TNBC cell lines, Hs578T and MDA-MB-231. Multimodal experiments were conducted to this end, using functional assays and microarrays. Arsenate was found to induce cytoskeletal alteration, autophagy and apoptosis in TNBC cells, and moderate effects in MCF-7 cells. Gene expression analysis showed that the TNBC cell lines’ response to arsenate was more prominent in the G2M checkpoint, autophagy and apoptosis compared to the Human Mammary Epithelial Cells (HMEC) and MCF-7 cell lines. We confirmed the downregulation of anti-apoptotic genes (MCL1, BCL2, TGFβ1 and CCND1) by qRT-PCR, and on the protein level, for TGFβ2, by ELISA. Insight into the mode of action of arsenate in TNBC cell lines it is provided, and we concluded that TNBC and non-TNBC cell lines reacted differently to arsenate treatment in this particular experimental setup. We suggest the future research of arsenate as a treatment strategy against TNBC. 相似文献
66.
Daniel Mihai Teleanu Adelina-Gabriela Niculescu Iulia Ioana Lungu Crina Ioana Radu Oana Vladcenco Eugenia Roza Bogdan Costchescu Alexandru Mihai Grumezescu Raluca Ioana Teleanu 《International journal of molecular sciences》2022,23(11)
Oxidative stress has been linked with a variety of diseases, being involved in the debut and/or progress of several neurodegenerative disorders. This review intends to summarize some of the findings that correlate the overproduction of reactive oxygen species with the pathophysiology of Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis. Oxidative stress was also noted to modify the inflammatory response. Even though oxidative stress and neuroinflammation are two totally different pathological events, they are linked and affect one another. Nonetheless, there are still several mechanisms that need to be understood regarding the onset and the progress of neurodegenerative diseases in order to develop efficient therapies. As antioxidants are a means to alter oxidative stress and slow down the symptoms of these neurodegenerative diseases, the most common antioxidants, enzymatic as well as non-enzymatic, have been mentioned in this paper as therapeutic options for the discussed disorders. 相似文献
67.
68.
Sven-Olov Daunfeldt Oana Mihaescu Helena Nilsson Niklas Rudholm 《Papers in Regional Science》2019,98(6):2295-2313
We investigate the effects of IKEA entry in three Swedish municipalities, finding that revenues for incumbent retailers located 1 km from the new IKEA store experienced a 7% increase due to positive spillover. The effect was insignificant for retailers located in city centres or more than 1 km from IKEA. Moreover, the positive agglomeration effects only dominate the negative competition effects for stores that sell complementary products, while same-market retailers located between 2 and 5 km from the new IKEA store experienced revenue loss due to IKEA entry. In contrast to retail revenues, the effects on employment were statistically insignificant. 相似文献
69.
This paper examines the degree of polarization in the European Union regional per capita income distribution between 1977
and 1999 from several complementary perspectives. Specifically, we have combined a non-parametric analysis with the information
provided by various polarization measures proposed by the literature on personal income distribution. The results reveal that
the European regions tend to cluster into different per capita income classes during the study period. Nevertheless, the level
of intra-distribution mobility is relatively low, especially in regions at the upper and lower ends of the distribution. In
any event, regional polarization has decreased over time, as a consequence of various factors sometimes working in opposite
directions. Additionally, the empirical evidence provided reveals that the geographical location of the various regions and
the differences in their productivity levels, play a major role in explaining the polarization patterns observed in the European
Union. 相似文献
70.
H Oana RW Hammond JJ Schwinefus SC Wang M Doi MD Morris 《Canadian Metallurgical Quarterly》1998,70(3):574-579
Capillary electrophoresis in dilute and semidilute (slightly entangled) hydroxyethyl cellulose (HEC) is shown to separate linear double-stranded DNA (ds-DNA) and supercoiled plasmid DNA in the size range 1-16 thousand base pairs in 3 min. The mobilities of linear ds-DNA fragments are stronger functions of electric field strength and buffer concentration than the mobilities of supercoiled plasmids. The effects of HEC concentration and molecular weight are similar for both forms of DNA. The behavioral differences, which are attributed to the greater stiffness of the plasmids, can be used to define conditions that maximize resolution of supercoiled and linear ds-DNA of the same or similar number of base pairs. 相似文献