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201.
《Arabian Journal of Chemistry》2022,15(11):104227
The docking study on a series of furo[1]benzofuran derivatives with ERα has been demonstrated. The synthesis and characterization of a series of furo[1]benzofuran derivatives were described. All the target compounds were conducted to in vitro for the inhibitory activities against human breast cancer strains T-47D, MCF-7 and toxicity against human liver normal cell strains HL7702 via MTT assay. Most of the target compounds possessed anti-estrogen receptor-dependent breast cancer activities with weak toxicity to healthy cell strains. The preliminary structure–activity relationships were discussed. 相似文献
202.
王贺元 《数学物理学报(A辑)》2020,(2):315-327
该文研究了平面不可压缩Navier-Stokes方程五模系统的力学机理及能量演化问题,通过将五模混沌系统转换成Kolmogorov形系统,把系统的力矩分为三种类型:惯性力矩,耗散力矩和外力矩.通过不同力矩的结合分析和研究了系统产生混沌的关键因素和物理意义.讨论了能量与雷诺数之间的关系.研究表明三种力矩的耦合是产生混沌的必要条件,而且只有耗散力矩和驱动力矩(外力矩)相匹配时,系统才能产生混沌,其中任何两种力矩耦合均不可能产生混沌.外力矩给系统提供能量,导致系统失稳出现分岔与混沌.引进Casimir函数分析系统的动力学行为和能量演化,并估计混沌吸引子的界.Casimir函数反映了能量转换和轨道与平衡点间的距离. 相似文献
203.
爆破地震效应对埋地管线的影响已成为工程爆破领域研究的热点。基于有限元软件ANSYS/LS-DYNA,以两种含Y型焊缝(坡口有2 mm余高焊缝和坡口无余高焊缝)的埋地X70钢管为例,数值模拟研究了TNT炸药量相同(4.473 kg)而炸高(60.0、85.0和110.0 cm)不同时,焊缝区附近埋地X70钢管的动力响应规律。研究表明:当炸高为60.0 cm时,焊缝有余高的管道受应力集中的影响较大,且先于焊缝无余高的管道进入屈服阶段;当炸高为60.0和85.0 cm时,焊缝有余高的管道整体抵抗变形的能力明显弱于焊缝无余高的管道。管土间的相互作用对X70管道背爆面有支撑作用,可有效地减小管道背爆面的位移。在相同条件下,焊缝有余高的X70管道抵抗振动的性能弱于焊缝无余高的管道,且与焊缝形式相比,炸高对含焊缝区的X70管道的最大振速起主要影响作用。 相似文献
204.
Hydrochloric Tramadol is a safe effective and not addictive emollient, the methods to gauge the quantity of it are Ultraviolet Spectrophotometry,HPLC, Gas Chromatography-Mass Spectrometry and so on. 相似文献
205.
206.
207.
《Journal of luminescence》1987,37(1):9-20
The Eu3+ ion occupies two different crystallographic sites in (Y1−xEux)2O3 and (Gd1−xEux)2O3, with site symmetry S6 and C2. Energy transfer over more than 7 Å occurs from Eu3+ (S6) ions to Eu3+ (C2) ions. This is shown to be a direct one-phonon assisted process, in combination with a one-site resonant two-phonon assisted process at higher temperatures. For x = 1 there is energy migration over the Eu3+ (C2) sublattice to quenching impurities. The presence of cooperative absorption points to superexchange interaction between the Eu3+ ions. 相似文献
208.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1987,43(8):1039-1043
Sodium salts of iminodiacetic acid (IDA), ethylenediaminetetraacetic acid (EDTA), 1,2-propylenediaminetetraacetic acid (PDTA) and 1,2-diaminocyclohexanetetraacetic acid (DCTA) were prepared by modification of the literature methods and their i.r. and Raman spectra were studied. The results obtained by application of both techniques allowed a better characterization of these polydentate ligands. Raman spectroscopy was specially useful in elucidating structural aspects in compounds containing acetate groups. 相似文献
209.
《Physics letters. [Part B]》1987,195(3):361-365
We find that a bent global string straightens itself out by dissipation into Nambu-Goldstone (NG) bosons in the order of one oscillation time and that the spectrum of radiated NG bosons is 1/k. In the early universe, the assumption that there is one global string per causal horizon is justified after an initial period during which the effect of the primordial plasma on the motion of the strings is non-negligible. We find that the upper bound that axion radiation by strings places on the axion decay constant is comparable to, but not more stringent than the one derived from coherent oscillations of the axion field, i.e. ∫a ≲ 1012GeV. We also discuss the model-dependence of this bound. 相似文献
210.
Vishal S. Patil Darasaguppe R. Harish Umashankar Vetrivel Subarna Roy Sanjay H. Deshpande Harsha V. Hegde 《Molecules (Basel, Switzerland)》2022,27(3)
Terminalia chebula Retz. forms a key component of traditional folk medicine and is also reported to possess antihepatitis C virus (HCV) and immunomodulatory activities. However, information on the intermolecular interactions of phytochemicals from this plant with HCV and human proteins are yet to be established. Thus, by this current study, we investigated the HCV NS3/4A inhibitory and host immune-modulatory activity of phytocompounds from T. chebula through in silico strategies involving network pharmacology and structural bioinformatics techniques. To start with, the phytochemical dataset of T. chebula was curated from biological databases and the published literature. Further, the target ability of the phytocompounds was predicted using BindingDB for both HCV NS3/4A and other probable host targets involved in the immune system. Further, the identified targets were docked to the phytochemical dataset using AutoDock Vina executed through the POAP pipeline. The resultant docked complexes with significant binding energy were subjected to 50 ns molecular dynamics (MD) simulation in order to infer the stability of complex formation. During network pharmacology analysis, the gene set pathway enrichment of host targets was performed using the STRING and Reactome pathway databases. Further, the biological network among compounds, proteins, and pathways was constructed using Cytoscape 3.6.1. Furthermore, the druglikeness, side effects, and toxicity of the phytocompounds were also predicted using the MolSoft, ADVERpred, and PreADMET methods, respectively. Out of 41 selected compounds, 10 were predicted to target HCV NS3/4A and also to possess druglike and nontoxic properties. Among these 10 molecules, Chebulagic acid and 1,2,3,4,6-Pentagalloyl glucose exhibited potent HCV NS3/4A inhibitory activity, as these scored a lowest binding energy (BE) of −8.6 kcal/mol and −7.7 kcal/mol with 11 and 20 intermolecular interactions with active site residues, respectively. These findings are highly comparable with Asunaprevir (known inhibitor of HCV NS3/4A), which scored a BE of −7.4 kcal/mol with 20 key intermolecular interactions. MD studies also strongly suggest that chebulagic acid and 1,2,3,4,6-Pentagalloyl glucose as promising leads, as these molecules showed stable binding during 50 ns of production run. Further, the gene set enrichment and network analysis of 18 protein targets prioritized 10 compounds and were predicted to potentially modulate the host immune system, hemostasis, cytokine levels, interleukins signaling pathways, and platelet aggregation. On overall analysis, this present study predicts that tannins from T. chebula have a potential HCV NS3/4A inhibitory and host immune-modulatory activity. However, further experimental studies are required to confirm the efficacies. 相似文献