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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
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Quentin Coquerel Claire Legendre Jacinthe Frangieh Stephan De Waard Jrme Montnach Leos Cmarko Joseph Khoury Charifat Said Hassane Dimitri Brard Benjamin Siegler Ziad Fajloun Harold De Pomyers Kamel Mabrouk Norbert Weiss Daniel Henrion Pascal Richomme Csar Mattei Michel De Waard Anne-Marie Le Ray Christian Legros 《Molecules (Basel, Switzerland)》2022,27(13)
Voltage-gated Na+ (NaV) channels are significant therapeutic targets for the treatment of cardiac and neurological disorders, thus promoting the search for novel NaV channel ligands. With the objective of discovering new blockers of NaV channel ligands, we screened an In-House vegetal alkaloid library using fluorescence cell-based assays. We screened 62 isoquinoline alkaloids (IA) for their ability to decrease the FRET signal of voltage sensor probes (VSP), which were induced by the activation of NaV channels with batrachotoxin (BTX) in GH3b6 cells. This led to the selection of five IA: liriodenine, oxostephanine, thalmiculine, protopine, and bebeerine, inhibiting the BTX-induced VSP signal with micromolar IC50. These five alkaloids were then assayed using the Na+ fluorescent probe ANG-2 and the patch-clamp technique. Only oxostephanine and liriodenine were able to inhibit the BTX-induced ANG-2 signal in HEK293-hNaV1.3 cells. Indeed, liriodenine and oxostephanine decreased the effects of BTX on Na+ currents elicited by the hNaV1.3 channel, suggesting that conformation change induced by BTX binding could induce a bias in fluorescent assays. However, among the five IA selected in the VSP assay, only bebeerine exhibited strong inhibitory effects against Na+ currents elicited by the hNav1.2 and hNav1.6 channels, with IC50 values below 10 µM. So far, bebeerine is the first BBIQ to have been reported to block NaV channels, with promising therapeutical applications. 相似文献
33.
Magdalena
widro-Pito Alicja Chromiec Marcin Zawadzki Renata Wietecha-Posuszny 《Molecules (Basel, Switzerland)》2022,27(13)
The present investigation utilised the quick and easy SPME/LC-MS method to determine selected narcotic substances and their metabolites in whole blood. The study included qualitative analysis and validation of the method. Analytes were determined in the linearity range of 25–300 ng/mL. The precision during and between days (in general CV < 13.41%), and the LOD which results in between 0.36 and 11.08 ng/mL, and the LOQ between 1.20 and 36.90 ng/mL were investigated. The validation results obtained, as well as the results of subsequent in-laboratory tests, confirmed the applicability of the method in the analysis of blood samples. An attempt to apply the method to the analysis of bone marrow samples has yielded promising results; however, more detailed studies are needed in this area. 相似文献
34.
Despoina-Eleni Zacharioudaki Ioannis Fitilis Melina Kotti 《Molecules (Basel, Switzerland)》2022,27(15)
Fluorescence spectroscopy is an optical spectroscopic method that has been applied for the assessment of environmental quality extensively during the last 20 years. Most of the earlier works have used conventional light sources in spectrofluorometers to assess quality. Many recent works have used laser sources of light for the same purpose. The improvement of the energy sources and of the higher resolution spectrometers has led to a tremendous increase in applications. The motivation for the present review study is the increasing use of laser sources in environmental applications. The review is divided in two parts. The fundamental principles of fluorescence spectroscopy are described in the first part. The environmental applications are described in the second part. 相似文献
35.
Li Xiong Jin Hu Zhao Yang Xianglin Li Hang Zhang Guanhua Zhang 《Molecules (Basel, Switzerland)》2022,27(12)
This study presents the construction and dielectric properties investigation of atomic-layer-deposition Al2O3/TiO2/HfO2 dielectric-film-based metal–insulator–metal (MIM) capacitors. The influence of the dielectric layer material and thickness on the performance of MIM capacitors are also systematically investigated. The morphology and surface roughness of dielectric films for different materials and thicknesses are analyzed via atomic force microscopy (AFM). Among them, the 25 nm Al2O3-based dielectric capacitor exhibits superior comprehensive electrical performance, including a high capacitance density of 7.89 fF·µm−2, desirable breakdown voltage and leakage current of about 12 V and 1.4 × 10−10 A·cm−2, and quadratic voltage coefficient of 303.6 ppm·V−2. Simultaneously, the fabricated capacitor indicates desirable stability in terms of frequency and bias voltage (at 1 MHz), with the corresponding slight capacitance density variation of about 0.52 fF·µm−2 and 0.25 fF·µm−2. Furthermore, the mechanism of the variation in capacitance density and leakage current might be attributed to the Poole–Frenkel emission and charge-trapping effect of the high-k materials. All these results indicate potential applications in integrated passive devices. 相似文献
36.
聚合物作为一种有机发光材料,由于在平板显示和光电子器件中的良好应用前景而受到广泛研究[1~2].近年来,一个重要进展是在聚合物中观测到了受激发射(简称Poly-mer激光)现象[3~6].Polymer激光最早是在溶液中实现的[3~4].作为一种新型... 相似文献
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39.
分析了连续激光辐照ZnSe/MgF2/K9滤光片引起透射特性的变化。在室温条件下,用波长0.632 8μm激光作为探测光束,测量了1.06μm连续激光辐照ZnSe/MgF2/K9滤光片温升引起薄膜折射率的改变,导致探测光束通过干涉滤光片后透过率的热致非线性变化。在光斑直径0.75mm条件下,测量了不同功率激光辐照ZnSe/MgF2/K9滤光片引起温升随时间的变化。在激光功率30W,辐照时间2.52s条件下,实验观测到ZnSe/MgF2/K9滤光片薄膜破坏温度约为90℃,辐照时间10s时干涉滤光片形成的薄膜龟裂形貌。 相似文献
40.