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排序方式: 共有274条查询结果,搜索用时 15 毫秒
61.
Vajiheh Neshati Samaneh Mollazadeh Bibi Sedigheh Fazly Bazzaz Antoine A. F. de Vries Majid Mojarrad Hojjat Naderi-Meshkin Zeinab Neshati Mahdi Mirahmadi Mohammad Amin Kerachian 《Applied biochemistry and biotechnology》2018,186(1):245-255
Since the adult mammalian heart has limited regenerative capacity, cardiac trauma, disease, and aging cause permanent loss of contractile tissue. This has fueled the development of stem cell-based strategies to provide the damaged heart with new cardiomyocytes. Bone marrow-derived mesenchymal stem cells (BM-MSCs) are capable of self-renewal and differentiation into cardiomyocytes, albeit inefficiently. MicroRNAs (miRNAs, miRs) are non-coding RNAs that have the potential to control stem cell fate decisions and are employed in cardiac regeneration and repair. In this study, we tested the hypothesis that overexpression of miR-499a induces cardiomyogenic differentiation in BM-MSCs. Human BM-MSCs (hBM-MSCs) were transduced with lentiviral vectors encoding miR-499a-3p or miR-499a-5p and analyzed by immunostaining and western blotting methods 14 days post-transduction. MiR-499a-5p-transduced cells adopted a polygonal/rod-shaped (myocyte-like) phenotype and showed an increase in the expression of the cardiomyocyte markers α-actinin and cTnI, as cardiogenic differentiation markers. These results indicate that miR-499a-5p overexpression promotes the cardiomyogenic differentiation of hBM-MSCs and may thereby increase their therapeutic efficiency in cardiac regeneration. 相似文献
62.
R. Amiri Dehkharghani M. Zandi Doust M. Tavassoti Kheiri H. Hossein Shahi 《Russian Journal of Applied Chemistry》2018,91(7):1165-1171
The goal of this research is to evaluate the impact of different parameters on corticosteroids entrapment in biocompatible poly-ε-caprolactone nanoparticles. These findings provide better insight on the designing carriers for drugs. Nanocapsules were synthesized by interfacial deposition and their morphology was determined by SEM. Drug entrapment efficiency and particle size distribution were assayed by HPLC and DLS, respectively. The samples were assessed for cytotoxicity using MTT reduction assay. The anti-inflammatory effect of the formulated drug was determined by induction of inflammation in treated as well as native laboratory animals. Statistical analysis of the data was performed using SPSS 18.0. 相似文献
63.
In this contribution, a novel label-free electrochemical biosensor for diclofenac (DCF) detection was developed using the unique properties of acid-oxidized carbon nanotubes (CNT), graphene oxide (GO), and Fe3O4 magnetic nanomaterials. The GO sheets and CNT were interlinked by ultrafine Fe3O4 nanoparticles forming three-dimensional (3D) architectures. The characterization of the nanocomposite was studied by scanning electron microscopy (SEM), energy-dispersive X-ray (EDS), and wavelength-dispersive X-ray (WDX) spectroscopy. Initially, aminated detection probe (aptamer) was surface-confined on the CNT/GO/Fe3O4 nanocomposite via the covalent amide bonds formed by the carboxyl groups on the CNT/GO and the amino groups on the oligonucleotides at the 5′ end. Our constructed folding-based electrochemical sensor was used for detection of target molecule utilizing structure-switching aptamers. Signaling arose from changes in electron transfer efficiency upon target-induced changes in the conformation of the aptamer probe. These changes were readily monitored using differential pulse voltammetry technique. This sensor exhibited binding affinities ranging from 100 to 1300 pM with a low detection limit of 33 pM. 相似文献
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65.
A facial, new, one‐pot method for the preparation of symmetrical organic trithiocarbonates from various alkyl halides and carbon disulfide is described. This is a convenient, clean, and mild procedure, which involves the use of the neutral, nontoxic, commercially available, and inexpensive reagent NH4OAc in the preparation of the trithiocarbonate ion from carbon disulfide. 相似文献
66.
67.
Fereshteh Ahmadi Zeinab Noroozi TissehMinoo Dabiri Ayoob Bazgir 《Comptes Rendus Chimie》2013,16(12):1086-1090
A practical and efficient method for the synthesis of 1,2,3-triazoles via the cycloaddition reaction of azides and CH-acids in the presence of 1,1,3,3-tetramethylguanidine (TMG) in ethanol at 30 °C has been reported. The simple experimental procedure, short reaction times, and good yields are the advantages of the present method. 相似文献
68.
Zirconium oxide complex anchored on boehmite nanoparticles as highly reusable organometallic catalyst for C–S and C–O coupling reactions
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Boehmite nanoparticles were prepared by a simple and inexpensive procedure in water using commercially available materials without inert atmosphere. Then, the surface of the boehmite nanoparticles was modified using 3‐mercaptopropyltrimethoxysilane and subsequently zirconium oxide was supported on the modified surface. Zirconium oxide supported on boehmite nanoparticles (Pr.S‐ZrO@boehmite) was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and inductively coupled plasma technique. The catalytic application of Pr.S‐ZrO@boehmite was studied in C–O and C–S coupling reactions for synthesis of valuable compounds such as ether and sulfide derivatives. All products were obtained in good to excellent yields and the catalyst could be recovered and reused several times without significant loss of catalytic efficiency. Furthermore, zirconium oxide is rarely used as catalyst for cross‐coupling reactions. 相似文献
69.
Alexander S. Karns Bryan D. Ellis Philipp C. Roosen Zeinab Chahine Karine G. LeRoch Christopher D. Vanderwal 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13887-13890
The flagship member of the antiplasmodial isocyanoterpenes, 7,20‐diisocyanoadociane (DICA), was synthesized from dehydrocryptone in 10 steps, and in 13 steps from commercially available material. Our previous formal synthesis was reengineered, leveraging only productive transformations to deliver DICA in fewer than half the number of steps of our original effort. Important contributions, in addition to the particularly concise strategy, include a solution to the problem of axial nucleophilic methylation of a late‐stage cyclohexanone, and the first selective synthesis and antiplasmodial evaluation of the DICA stereoisomer with both isonitriles equatorial. 相似文献
70.
Research on Chemical Intermediates - TiO2 nanotubes and Ag/TiO2 nanotubes (TNT) have been synthesized by simple hydrothermal and solvothermal method and were characterized by XRD, UV, ICP, TEM,... 相似文献