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排序方式: 共有208条查询结果,搜索用时 149 毫秒
101.
Shady Farah Wahid Khan Ira Farber Dana Kesler‐Shvero Nurit Beyth Ervin I. Weiss Abraham J. Domb 《先进技术聚合物》2013,24(5):446-452
Quaternary ammonium polyethylenimine (QA‐PEI) nanoparticles were synthesized by PEI crosslinking and alkylation with octyliodide followed by quaternization by methyl iodide. The present study focuses on the reproducibility of particles formation with respect to particle size, positive charge, oxidative, thermal stability and antibacterial activity. The QA‐PEI‐based nanoparticles with particle size in the range of 160–190 nm were synthesized in high reproducibility and showed high chemical stability against environmental changes including exposure to different oxidizers and storage conditions. QA‐PEI nanoparticles incorporated in dental restorative resin composites at 2% w/w demonstrated strong antibacterial activity. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
102.
Farah Asaad Goda Pelanyte Jincy Philip Christer Dahlin Lena Larsson 《Molecules (Basel, Switzerland)》2020,25(24)
The contribution of epigenetic mechanisms as a potential treatment model has been observed in cancer and autoimmune/inflammatory diseases. This review aims to put forward the epigenetic mechanisms as a promising strategy in implant surface functionalization and modification of biomaterials, to promote better osseointegration and bone regeneration, and could be applicable for alveolar bone regeneration and osseointegration in the future. Materials and Methods: Electronic and manual searches of the literature in PubMed, MEDLINE, and EMBASE were conducted, using a specific search strategy limited to publications in the last 5 years to identify preclinical studies in order to address the following focused questions: (i) Which, if any, are the epigenetic mechanisms used to functionalize implant surfaces to achieve better osseointegration? (ii) Which, if any, are the epigenetic mechanisms used to functionalize biomaterials to achieve better bone regeneration? Results: Findings from several studies have emphasized the role of miRNAs in functionalizing implants surfaces and biomaterials to promote osseointegration and bone regeneration, respectively. However, there are scarce data on the role of DNA methylation and histone modifications for these specific applications, despite being commonly applied in cancer research. Conclusions: Studies over the past few years have demonstrated that biomaterials are immunomodulatory rather than inert materials. In this context, epigenetics can act as next generation of advanced treatment tools for future regenerative techniques. Yet, there is a need to evaluate the efficacy/cost effectiveness of these techniques in comparison to current standards of care. 相似文献
103.
Preparation of radioidinated L-α-methyl tyrosine by the oxidative radioiodination using chloramine-T (CAT) and iodogen (1,3,4,6-tetrachloro,-3α,
6α-diphenyl glycoluril) to generate electrophilic radioiodine has been carried out. The factors affecting the labeling yield
such as pH of the medium, reaction time, substrate and oxidizing agent concentrations have been investigated to optimize the
conditions for the preparation of radioiodinated L-α-methyl tyrosine in high radiochemical yields. Side product impurities
were observed at long reaction times and high oxidizing agent concentrations. Maximum radiochemical yields of 89.7±1.5% and
87.8±1.6% were obtained in case of CAT and iodogen, respectively. Separation and purification by high pressure liquid chromatography
(HPLC) resulted in radiochemically pure products. Using high specific activity123I, the SPECT brain imaging agent can be prepared. 相似文献
104.
The extraction of Co3+ from 0.1M aqueous acetate medium buffered to pH 5.3 by thenoyltrifluoroacetone (HTTA) in benzene and by 8-quinolinol (HQ) also in benzene at various temperatures has been studied. The species formed were Co(OH)2 (TTA)·(HTTA)2 and Co(Q3)·2HQ, respectively. 1,10-phenanthroline (Phen) as a base was also mixed with HTTA to form the species Co(OH)2(TTA)·(HTTA). Phen and Co(OH)2 (TTA)(HTTA)·2Phen. No synergism was observed upon the addition of Phen to HQ. 相似文献
105.
Mohamed Haouari Hanif D. Sherali Farah Zeghal Mansour Najla Aissaoui 《Computational Optimization and Applications》2011,49(2):213-239
We describe models and exact solutions approaches for an integrated aircraft fleeting and routing problem arising at TunisAir.
Given a schedule of flights to be flown, the problem consists of determining a minimum cost route assignment for each aircraft
so as to cover each flight by exactly one aircraft while satisfying maintenance activity constraints. We investigate two tailored
approaches for this problem: Benders decomposition and branch-and-price. Computational experiments conducted on real-data
provide evidence that the branch-and-price approach outperforms the Benders decomposition approach and delivers optimal solutions
within moderate CPU times. On the other hand, the Benders algorithm yields very quickly high quality near-optimal solutions. 相似文献
106.
Farah Alimagham Mieszko Dyliński Anne H. Gelebart Konrad J. Jakubowski Janusz Meylahn Yogesh K. Murugesan 《Liquid Crystals Today》2013,22(1):15-24
Two new 5‐substituted 1,3,4‐thiadiazole‐2‐carboxylate esters have been synthesized via ring closure of appropriate tricarbonyl precursors using Lawesson's reagent. The chemistry described is the first report of such methodology in the organic literature. The new materials display broad smectic C phases and show considerable potential for use in electrooptic display devices. 相似文献
107.
Nonlinear Dynamics - Jaya algorithm is one of the recent algorithms developed to solve optimization problems. The basic concept of this algorithm consists in moving the obtained solution, for a... 相似文献
108.
Ilijas Farah 《Journal of Functional Analysis》2009,256(11):3841-3846
We answer a question of E. Kirchberg (personal communication): does the relative commutant of a separable C∗-algebra in its ultrapower depend on the choice of the ultrafilter? 相似文献
109.
A new method for obtaining strong S-boxes based on chaotic map and Teaching–Learning-Based Optimization (TLBO) is presented in this paper. Our method presents eight rounds; each round contains two transformations: row left shifting and columnwise rotation. The vectors for the transformations are different from one round to another, and they are controlled by two keys to the logistic map. These two keys are optimized by using TLBO which aims to construct a strong S-box that satisfies to the criteria set in advance. Test for the following criteria such as bijectivity, nonlinearity, strict avalanche criteria, equiprobable inputs/outputs XOR distribution is analyzed. Additionally, we will provide many comparisons with other S-boxes and test of the sensitivity to keys. The results of performance test show that the proposed design S-boxes presents good cryptography proprieties and can resist to several attacks. 相似文献
110.
Luiz Gustavo Farah Ademir Pastor 《Journal of Mathematical Analysis and Applications》2010,368(1):330-349
We study the local and global well-posedness of the periodic boundary value problem for the nonlinear Schrödinger-Boussinesq system. The existence of periodic traveling-wave solutions as well as the orbital stability of such solutions are also considered. 相似文献