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151.
The aim of the present study was to investigate the chemical constituents and hepatoprotective effect of Ficus ingens (Miq.) Miq. (Moraceae) extract against carbon tetrachloride-induced acute liver damage in male Wistar albino rats. The ethanol extract of F. ingens, was subjected to phytochemical study. In addition, its acute and sub-chronic toxicities were assessed. Eight compounds were isolated from this plant and identified as β-sitosterol, β-sitosterol glucoside, chryasophanol, 7-hydroxy-2,5 dimethyl chromen-4-one, quercetin, Aloe emodin glucoside, rutin and Patuletin-3′-O-methyl-3-O-rutinoside. The structure elucidation was based on 1H and 13C NMR, proton–proton correlation spectroscopy (1H–1H Cosy), distortionless enhancement by polarization transfer (DEPT), Heteronuclear Multiple-Quantum Correlation (HMQC), and heteronuclear multiple bond correlations spectrum (HMBC). Hepatotoxicity induced with CCl4 was evidenced by elevation of liver marker enzymes (ALT, AST, ALP and LDH) and TB content in serum. In addition, antioxidant enzymes were drastically inhibited with significant reduction of GSH and increased LPO in liver homogenate of CCl4-intoxicated rats. Pre-treatment with F. ingens (200 and 400 mg/kg) and silymarin (50 mg/kg) avoided the changes observed in CCl4-intoxicated rats. In conclusion, the ethanol extract of F. ingens showed protective activity against liver injury, which might be developed into a new hepatoprotective agent.  相似文献   
152.
In the title complex, [Cu(C7H4NO3S)2(C2H7NO)2], the CuII centre lies on an inversion centre and exhibits octahedral coordination, with the two ethano­lamine (Hea) and two saccharinate [sac; anionic 1,2-benziso­thia­zol-3(2H)-one 1,1-dioxide] ligands in a trans configuration. The bidentate Hea ligands bridge axial and equatorial positions and the sac anions occupy equatorial sites around the distorted octahedral copper(II) centre [Cu—O = 2.3263 (16), Cu—NHea = 1.9923 (16) and Cu—Nsac = 2.1776 (16) Å].  相似文献   
153.

We propose a numerical method to obtain the transient and first passage time distributions of first- and second-order Multi-Regime Markov Fluid Queues (MRMFQ). The method relies on the observation that these transient measures can be computed via the stationary analysis of an auxiliary MRMFQ. This auxiliary MRMFQ is constructed from the original one, using sample path arguments, and has a larger cardinality stemming from the need to keep track of time. The conventional method to approximately model the deterministic time horizon is Erlangization. As an alternative, we propose the so-called ME-fication technique, in which a Concentrated Matrix Exponential (CME) distribution replaces the Erlang distribution for approximating deterministic time horizons. ME-fication results in much lower state-space dimensionalities for the auxiliary MRMFQ than would be with Erlangization. Numerical results are presented to validate the effectiveness of ME-fication along with the proposed numerical method.

  相似文献   
154.
Various aryl-substituted anthraquinones were prepared by palladium(0)-catalyzed Suzuki-Miyaura cross-coupling reactions of the bis(triflate) of 1,3-dihydroxyanthraquinone. A very good site-selectivity in favor of position 1 was observed which can be explained by the electronic influence of the neighboring carbonyl group.  相似文献   
155.
Macitentan is an endothelin receptor antagonist commonly used in the treatment of pulmonary arterial hypertension (PAH). A novel, rapid, simple and sensitive UPLC–MS/MS method was developed and validated for pharmacokinetic study and the determination of macitentan in PAH patients. Macitentan and bosentan, which are used as internal standards, were detected using atmospheric pressure chemical ionization in positive ion and multiple reaction monitoring mode by monitoring the mass transitions m/z 589.1 → 203.3 and 552.6 → 311.5, respectively. Chromatographic separation was performed on a reverse‐phase C18 column (5 μm, 4.6 × 150 mm) with an isocratic mobile phase, which consisted of water containing 0.2% acetic acid–acetonitrile (90:10, v/v) at a flow rate of 1 mL/min. Retention times were 1.97 and 1.72 min for macitentan and IS, respectively. The calibration curve with high correlation coefficient (0.9996) was linear in the range 1–500 ng/mL. The lower limit of quantitation and average recovery values were determined as 1 ng/mL and 89.8%, respectively. This method is the first UPLC–MS/MS method developed and validated for the determination of macitentan from human plasma. The developed analytical method was fully validated for linearity, selectivity, specificity, accuracy, precision, sensitivity, stability, matrix effect and recovery according to US Food and Drug Administration guidelines. The developed method was applied successfully for pharmacokinetic study and the determination of macitentan in PAH patients.  相似文献   
156.
Au nanoparticles are functionalized with thioaniline electropolymerizable units and mercaptophenyl boronic acid ligands. Flavin adenine dinucleotide (FAD) is linked to the boronic acid ligands and apo‐glucose oxidase, apo‐GOx, is reconstituted on the FAD cofactor units to yield enzymes in a structurally‐aligned configuration in respect to the Au NPs. Electropolymerization of the enzyme‐functionalized Au NPs on a thioaniline‐modified Au electrode yields a three‐dimensional bis‐aniline‐crosslinked Au NPs/reconstituted glucose oxidase matrix on the electrode that reveals effective electrical contacting with the electrode.  相似文献   
157.
158.
We study the Magidor iteration of Prikry forcings, and the resulting normal measures on ${\kappa}$ , the first measurable cardinal in a generic extension. We show that when applying the iteration to a core model below ${0^{\P}}$ , then there exists a natural correspondence between the normal measures on ${\kappa}$ in the ground model, and those of the generic extension.  相似文献   
159.
Patulin (PAT) and citrinin (CTN) are the most common mycotoxins produced by Penicillium and Aspergillus species and are often associated with fruits and fruit by-products. Hence, simple and reliable methods for monitoring these toxins in foodstuffs are required for regular quality assessment. In this study, we aimed to establish a cost-effective method for detection and quantification of PAT and CTN in pome fruits, such as apples and pears, using high-performance liquid chromatography (HPLC) coupled with spectroscopic detectors without the need for any clean-up steps. The method showed good performance in the analysis of these mycotoxins in apple and pear fruit samples with recovery ranges of 55–97% for PAT and 84–101% for CTN, respectively. The limits of detection (LOD) of PAT and CTN in fruits were 0.006 µg/g and 0.001 µg/g, while their limits of quantification (LOQ) were 0.018 µg/g and 0.003 µg/g, respectively. The present findings indicate that the newly developed HPLC method provides rapid and accurate detection of PAT and CTN in fruits.  相似文献   
160.
Electrophoretic deposition (EPD) is a cheap and simple processing technique based on the movement of charged particles in an electrical field (electrophoresis) followed by deposition of these particles on the electrode that attracted them [O. VanderBiest, L.J. Vandeperre, Electrophoretic deposition of materials, Annu. Rev. Mater. Sci. 29 (1999) 327–352]. If not for electrolysis, water would be the solvent of choice instead of the currently commercially used organics. In this work we prove that high voltages can be used for electrophoretic deposition from aqueous suspensions without decomposition of water when applying an asymmetric alternating electric field. The experimental results show that deposits formed using these fields have a green density and surface comparable and even better than those typically obtained using the classic EPD systems. As a result volatile, expensive and environmentally unfriendly solvents are no longer a necessity.  相似文献   
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