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21.
Abd El Raheim M. Donia Gamal A. Soliman Ahmed M. Zaghloul Saleh I. Alqasoumi Amani S. Awaad Asmaa M. Radwan Omer A. Basodan 《Journal of Saudi Chemical Society》2013,17(1):125-133
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
22.
Zaghloul U Bhushan B Papaioannou G Coccetti F Pons P Plana R 《Journal of colloid and interface science》2012,365(1):236-253
The work presents a comprehensive package of novel nanoscale characterization techniques to study dielectric charging in electrostatic nano- and microelectromechanical systems (NEMS and MEMS). The proposed assessment methodologies are based on the force-distance curve (FDC) measurements performed using an atomic force microscope (AFM) to measure, for the first time, the induced surface potential and adhesive force over charged dielectric films. They were employed to study plasma enhanced chemical vapor deposition (PECVD) silicon nitride films for application in electrostatic capacitive RF MEMS switches. Three different techniques were introduced including the application of FDC measurements to study charging in bare SiN(x) films, metal-insulator-metal (MIM) capacitors, and MEMS switches. The results from the three methods were correlated and compared with the published data from other characterization techniques, mainly charge/discharge current transient (C/DCT) and Kelvin probe force microscopy (KPFM). The unique advantages of the proposed FDC-based characterization techniques are twofold. First, they can measure the multiphysics coupling between the dielectric charging phenomenon and tribological issues at the interface between the switch bridge and the dielectric surface. Second, the FDC-based techniques can measure larger levels of induced surface potential over charged dielectric films which results from the high electric field normally used to actuate MEMS switches. Based on the proposed FDC techniques, the influence of several parameters on dielectric charging/discharging processes was investigated: the dielectric film thickness, deposition conditions, substrate, and electrical stress conditions. 相似文献
23.
Fundamental view on the calculation of internal partition functions using occupational probabilities
From first principles, the author gathers a few general rules that need to be abided by in the calculation of the internal partition functions (IPFs) of individual molecules. These rules are violated in many schemes in the literature where occupational probabilities are used including those using the Planck–Larkin partition function (PLPF) within the chemical picture. Considering these rules is useful from conceptual and practical points of view. A solution is introduced to assure fulfilling the above mentioned rules when using occupational probabilities. Sample calculations are performed showing quantitative significance of inaccuracies caused by dishonoring such rules. 相似文献
24.
Yhiya M. Amen Amani M. Marzouk Mona G. Zaghloul Mohamed S. Afifi 《Natural product research》2015,29(6):511-517
A new acylated kaempferol glycoside, kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 6)-O-[β-d-glucopyranosyl-(1 → 2)-4-O-acetyl-α-l-rhamnopyranosyl-(1 → 2)]-β-d-galactopyranoside, has been isolated from the leaves of Tipuana tipu (Benth.) Lillo growing in Egypt, along with three known flavonol glycosides, kaempferol 3-O-rutinoside, quercetin 3-O-rutinoside (rutin) and kaempferol 3-O-[α-l-rhamnopyranosyl-(1 → 6)]-[α-l-rhamnopyranosyl-(1 → 2]-β-d-glucopyranoside. Structure elucidation was achieved through different spectroscopic methods. Structure relationship with anti-inflammatory activity using carrageenin-induced rat paw oedema model is discussed. 相似文献
25.
Zaghloul E. Kandeel Ahmad M. Farag Mohamed R. Shaaban Mohamed H. Elnagdi 《Heteroatom Chemistry》1996,7(1):35-38
A facile, one-step synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-benzopyran derivatives 4a-e via cyclo-addition reactions of acrylonitrile derivatives 1a-e with 1,3-cyclohexandione 2 is described. On the other hand, the reactions of 2 with the thioamides 1f-h afforded 5-oxo-5,6,7,8-tetrahydroquinoline derivatives 9a-c in good yields. The structures of the prepared compounds were established from their elemental analyses, spectroscopic data, and by their chemical transformations. © 1996 John Wiley & Sons, Inc. 相似文献
26.
Yasser A. El-Amier Walid Soufan Khalid F. Almutairi Nouf S. Zaghloul Ahmed M. Abd-ElGawad 《Molecules (Basel, Switzerland)》2022,27(1)
Halophytes have been characterized as a potential resource for fiber, food, fodder, and bioactive compounds. Proximate composition, bioactive compounds, and antioxidant activity of five wild dominant halophytes (Arthrocnemum macrostachyum, Halocnemum strobilaceum, Limoniastrum monopetalum, Limoniastrum pruinosum, and Tamarix nilotica) naturally growing along the Nile Delta coast were assessed. The soil supporting these halophytes was sandy to sand-silty, alkaline, with low organic carbon, and relatively high CaCO3. H. strobilaceum attained the highest moisture content, ash, crude fiber, lipids, and total soluble sugars. L. monopetalum showed the highest content of crude protein (18.00%), while T. nilotica had the highest content of total carbohydrates. The studied halophytes can be ranked according to their nutritive value as follows: H. strobilaceum > L. monopetalum > A. macrostachyum > L. pruinosum > T. nilotica. A. macrostachyum attained the highest amount of Na+, K+, Ca2+, and Mg2+. A. macrostachyum showed a high content of phenolic compounds, while H. strobilaceum was rich in tannins and saponin contents. The MeOH extract of A. macrostachyum and H. strobilaceum exhibited substantial antioxidant activity. The present results showed that the studied halophytes could be considered as candidates for forage production or used as green eco-friendly natural resources for bioactive compounds. 相似文献
27.
Cellulose - Unique technique is currently demonstrated for preparation of ultraviolet protective cotton fabrics with full shielding effect, via self-implantation of palladium (Pd) nanoclusters.... 相似文献
28.
Linearly polarized light incident on a transparent film coating a transparent substrate remains linearly polarized after reflection only at a set of discrete angles of incidence φm (m integer). Measurement of these angles of incidence for zero reflection-induced ellipticity (ZRIE) allows simple, direct and explicit determination of the refractive index and thickness of the film, independent of the substrate refractive index. The latter can be separately and easily determined from the azimuths of the incident and reflected linear vibrations at one of the angles of incidence φm or, alternatively, from the angle of refraction of light into the substrate using Snell's law. The proposed technique requires that the thickness of the film exceed one-fourth the wavelength of light in the medium of the film, and that it does not fall in a “higher-order” thickness gap when the ratio of the refractive index of the film to that of the ambient is greater than . 相似文献
29.
R. Zaghloul W. H. El-Abbady N. S. Ghoma 《Journal of Radioanalytical and Nuclear Chemistry》1987,116(2):235-241
The trace elements As, Co, Eu, Ga, La, Sb, Sc, Sm, U and W and the major constituents Fe and Na were determined in four domestic phosphate rocks by the monostandard epithermal neutron activation technique. Samples of 0.1 g were irradiated in the Egyptian 2 MW ERR-1 reactor under Cd cover, and the induced gamma activities measured after 6 h, 7 d and 8 w with a Hp Ge detector coupled to a computerized multichannel analyzer. Uranium has been used as a monostandard due to its relatively high resonance integral value (I0=274.6 b) and because it is one of the elements to be determined more accurately. The present data are compared with those obtained by instrumental neutron activation analysis (INAA) method performed at Institute of Radiochemistry, Karlsruhe. The observed discrepancies do not exceed 12% in average. The present method is a practical alternative for trace element analysis. 相似文献
30.
M. A. Raoof A. Naeem R. Zaghloul A. F. Abdul-Fattah M. A. Obeid 《Journal of Radioanalytical and Nuclear Chemistry》1980,60(1):273-279
Multielemental analysis of an iron ore from the Kingdom of Saudi Arabia was carried out using Instrumental Neutron Activation
Analysis (INAA) with Ge(Li) detectors. The spectra were analysed with the help of an off-line computer programme. Twenty five
elements are observed to be present in the ore. The elements of major interest are Fe, Al and Ca with 51.5%, 3.6% and 2.2%
concentrations, respectively. 相似文献