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排序方式: 共有172条查询结果,搜索用时 15 毫秒
1.
Karny M Grzywacz RK Batchelder JC Bingham CR Gross CJ Hagino K Hamilton JH Janas Z Kulp WD McConnell JW Momayezi M Piechaczek A Rykaczewski KP Semmes PA Tantawy MN Winger JA Yu CH Zganjar EF 《Physical review letters》2003,90(1):012502
Fine structure in proton emission from the 3.1(3) mus activity of 145Tm was discovered by using a novel technique of digital processing of overlapping recoil implantation and decay signals. Proton transitions to the ground state of 144Er and to its first excited 2(+) state at 0.33(1) MeV with a branching ratio I(p)(2(+))=9.6+/-1.5% were observed. The structure of the 145Tm wave function and the emission process were analyzed by using particle-core vibration coupling models. 相似文献
2.
M. N. M. Allam A. M. Zenkour & R. Tantawy 《advances in applied mathematics and mechanics.》2014,6(2):233-246
This paper presents an analytical solution for the interaction of electric potentials,
electric displacement, elastic deformations, and describes hygrothermal effect responses
in hollow and solid cylinders, subjected to mechanical load and electric potential. Exact
solutions for displacement, stresses and electric potentials in functionally graded
piezoelectric material are determined using the infinitesimal theory. The material properties
coefficients of the present cylinder are assumed to be graded in the radial direction by a
power law distribution. Numerical examples display the significant of influence of material
inhomogeneity. It is interesting to note that selecting a specific value of inhomogeneity
parameter can optimize the piezoelectric hollow and solid cylinders responses, which will
be of particular importance in modern engineering designs. 相似文献
3.
The present study evaluates the photodynamic damage with 5-aminolevulinic acid (5-ALA) using HeLa as experimental model. HeLa
cell line was irradiated with red light (He-Ne laser, λ = 632.8 CW nm). The influence of different incubation times and concentrations
of 5-ALA, different irradiation doses and various combinations of photosensitizer and light doses on the cellular viability
of HeLa cells were studied. The optimal uptake of photosensitizer ALA in HeLa cells was investigated by means of PpIX fluorescence
intensity by exciting the HeLa cell suspension at 450 nm and a detection wavelength set at 690 nm. Cells viability was determined
by means of trypan blue solution. The spectrometric measurements showed that the maximal cellular uptake of 5-ALA occurred
after 4 h in vitro incubation. We found that the combination with 5-ALA and laser irradiation leads to time/concentration-dependent
increase of cells death and also energy doses-dependent enlarge the cells death. The fluorescence intensity after PDD of carcinoma
cells reduce when compared with the control group. The fluorescence emission spectral profiles after PDD of carcinoma cells
showed a dip around 425–525 nm when compared with the control group. This may be due to the damage of mitochondria component
of cells. The percentage of HeLa cells after PDD shows that the percentage of cells survival rate as function of laser dose
(power). Hence it is clear that at 200 μg/ml ALA and 20 mW laser irradiation, more than 70% of HeLa cells were dead after
15 min. 相似文献
4.
5.
Mohammed S. M. Moustafa A. H. El-Sayed H. A. Amin A. S. Haggar A. Tantawy E. S. Haggam R. A. 《Russian Journal of General Chemistry》2022,92(9):1806-1813
Russian Journal of General Chemistry - A highly efficient synthetic methodology for the preparation of 2-thioxocytosine was achieved by the nucleophilic addition of thiourea to... 相似文献
6.
Clayton A. Whitmore Mariam I. Boules William J. Behof Justin R. Haynes Dmitry Koktysh Adam J. Rosenberg Mohammed N. Tantawy Wellington Pham 《Molecules (Basel, Switzerland)》2021,26(8)
Promethazine, an antihistamine drug used in the clinical treatment of nausea, has been demonstrated the ability to bind Abeta in a transgenic mouse model of Alzheimer’s disease. However, so far, all of the studies were performed in vitro using extracted tissues. In this work, we report the design and synthesis of a novel [11C]promethazine PET radioligand for future in vivo studies. The [11C]promethazine was isolated by RP-HPLC with radiochemical purity >95% and molar activity of 48 TBq/mmol. The specificity of the probe was demonstrated using human hippocampal tissues via autoradiography. 相似文献
7.
Hafiz Ejaz Ahmed Yasir Iqbal Muhammad Hammad Aziz Muhammad Atif Zahida Batool Atif Hanif Nafeesah Yaqub W. A. Farooq Shafiq Ahmad Amanullah Fatehmulla Hijaz Ahmad 《Molecules (Basel, Switzerland)》2021,26(15)
Metal oxide nanoparticles synthesized by the biological method represent the most recent research in nanotechnology. This study reports the rapid and ecofriendly approach for the synthesis of CeO2 nanoparticles mediated using the Abelmoschus esculentus extract. The medicinal plant extract acts as both a reducing and stabilizing agent. The characterization of CeO2 NPs was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Fourier transform infrared spectroscopy (FTIR). The in vitro cytotoxicity of green synthesized CeO2 was assessed against cervical cancerous cells (HeLa). The exposure of CeO2 to HeLa cells at 10–125 µg/mL caused a loss in cellular viability against cervical cancerous cells in a dose-dependent manner. The antibacterial activity of the CeO2 was assessed against S. aureus and K. pneumonia. A significant improvement in wound-healing progression was observed when cerium oxide nanoparticles were incorporated into the chitosan hydrogel membrane as a wound dressing. 相似文献
8.
Nafisa Gull Shahzad Maqsood Khan Muhammad Taqi Zahid Butt Saba Zia Syed Khalid Atif Islam Imran Sajid Rafi Ullah Khan Martin William King 《先进技术聚合物》2019,30(9):2414-2424
Hydrogel‐based drug delivery systems can leverage therapeutically favorable upshots of drug release and found clinical uses. Hydrogels offer temporal and spatial control over the release of different therapeutic agents. Because of their tailor made controllable degradability, physical properties, and ability to prevent the labile drugs from degradation, hydrogels provide platform on which diverse physicochemical interactions with entrapped drugs cause to control drug release. Herein, we report the fabrication of novel vinyltrimethoxy silane (VTMS) cross‐linked chitosan/polyvinyl pyrrolidone hydrogels. Swelling in distilled water in conjunction with different buffer and electrolyte solutions was performed to assess the swellability of hydrogels. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X‐ray diffraction (XRD) analysis were further conducted to investigate the possible interactions between components, thermal stability, and crystallinity of as‐prepared hybrid hydrogels, respectively. In vitro time‐dependent biodegradability, antimicrobial study, and cytotoxicity were also carried out to evaluate their extensive biocompatibility and cytotoxic behavior. More interestingly, in vitro drug release study allowed for the controlled release of cephradine. Therefore, this facile strategy developed the novel biocompatible and biodegradable hybrid hydrogels, which could significantly expand the scope of these hydrogels in other biomedical applications like scaffolds, skin regeneration, tissue engineering, etc. 相似文献
9.
毛细管电泳具有分析时间短,分离效率高,样品消耗量少等优点,在生物样品分离,特别是蛋白质分析领域有重要应用。然而,毛细管内壁硅羟基的解离给分离结果带来诸多不良影响。聚合物涂层能够抑制蛋白质在毛细管内壁的吸附以及调控电渗流,故对毛细管内壁进行有效修饰能够提高其对蛋白质的分离效率及分离稳定性。该文主要综述了动态及静态聚合物涂层毛细管的最新研究进展,并概述了近些年基于多巴胺/聚多巴胺发展起来的涂层毛细管的研究进展,最后展望了聚合物涂层毛细管的发展趋势。 相似文献
10.
Atif Ali Fan Cheng Wei-Hong Wen Xiao Ying Jaipal Kandhadi Hui Wang Hai-Yang Liu Chi-Kwong Chang 《中国化学快报》2018,29(12):1888-1892
A new bulky 2-chloro-5,10,15-tris(2,4,6-triphenylphenyl)-corrole was casually synthesized and the effect of mono-β-chlorination on its photophysical, electrochemical properties and light-induced singlet oxygen generation was investigated. 相似文献