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71.
Abdelhalim B. Mahmoud Shereen Abd Algaffar Wendy van de Sande Sami Khalid Marcel Kaiser Pascal Mser 《Molecules (Basel, Switzerland)》2021,26(13)
Redox-active drugs are the mainstay of parasite chemotherapy. To assess their repurposing potential for eumycetoma, we have tested a set of nitroheterocycles and peroxides in vitro against two isolates of Madurella mycetomatis, the main causative agent of eumycetoma in Sudan. All the tested compounds were inactive except for niclosamide, which had minimal inhibitory concentrations of around 1 µg/mL. Further tests with niclosamide and niclosamide ethanolamine demonstrated in vitro activity not only against M. mycetomatis but also against Actinomadura spp., causative agents of actinomycetoma, with minimal inhibitory concentrations below 1 µg/mL. The experimental compound MMV665807, a related salicylanilide without a nitro group, was as active as niclosamide, indicating that the antimycetomal action of niclosamide is independent of its redox chemistry (which is in agreement with the complete lack of activity in all other nitroheterocyclic drugs tested). Based on these results, we propose to further evaluate the salicylanilides, niclosamide in particular, as drug repurposing candidates for mycetoma. 相似文献
72.
The approximate solutions of Dirac equation with Morse potential in the presence of Coulomb-like tensor potential are obtained by using Laplace transform (LT) approach. The energy eigenvalue equation of the Dirac particles is found and some numerical results are obtained. By using convolution integral, the corresponding radial wave functions are presented in terms of confluent hypergeometric functions. 相似文献
73.
74.
Systems with singular-higher order Lagrangians are investigated by two methods: Dirac method and Hamilton-Jacobi method. An example is studied and it is shown that the Hamilton-Jacobi method gives the correct canonical generalized equations of motion, contrary to Dirac method, where Dirac conjecture is invalid. 相似文献
75.
A method which employs an integrating sphere and a single-wavelength (1.6 μm) pyrometer for measuring the spectral effective emissivities of superalloys in the temperature range (=650–1050°C) is described. The spectral effective emissivities for five superalloys, namely, MARM-247, MARM-509, CMSX-4, Inconel-718, N-155 and two René-N6 samples coated with YSZ thermal barrier coating were measured. Correcting the pyrometer measurements for the variations in the object emissivity would reduce the uncertainty in the temperature measurements to <±1%. 相似文献
76.
The formyl carbonyl group in bis(4-methoxyphenyl)-acetaldehyde does not contribute to the formation of the carbonyl group in 4,4′-dimethoxydeoxybenzoin when the former rearranges to the latter by treatment with 50% (w/w) sulfuric acid. 相似文献
77.
Sami A. Shakir 《Physics letters. A》1983,93(9):510-512
We describe two methods for employing materials with giant Kerr nonlinearities for modulating waveguides. A beam, of relatively intense light, is used to vary the propagation constant of a waveguide with the guiding layer, or the substrate, made from a nonlinear material. 相似文献
78.
Sami F. Masri 《Experimental Mechanics》1967,7(2):49-55
An experimental study is made of the general behavior of single-particle impact dampers, using an electronic-analog computer
and a mechanical model. It is found that, under practically realizable conditions, impact damping is effective in reducing
the vibration-amplitude levels resulting from sinusoidal or random excitation.
Paper was presented at 1966 SESA Spring Meeting held in Detroit, Mich., on May 4–6. 相似文献
79.
Quantum confinement effect on the energy levels of Eu2+ doped K2Ca2(SO4)3 nanoparticles has been observed. The broad photoluminescence (PL) emission band of Eu2+ doped K2Ca2(SO4)3 microcrystalline sample observed at ~436 nm is found to split into two narrow well resolved bands, located at 422 and 445 nm in the nanostructure form of this material. This has been attributed to the reduction in the crystal field strength of the nanomaterials, which results in widening the energy band gap and splitting the broad 4f65d energy level of Eu2+. Energy band gap values of the micro and nanocrystalline K2Ca2(SO4)3 samples were also determined by measuring the UV–visible absorption spectra. These values are 3.34 and 3.44 eV for the micro and nanocrystalline samples, respectively. These remarkable results suggest that activators having wide emission bands might be subjected to weak crystal strength via nanostructure materials to modify their electronic transitions. This might prove a powerful technique for producing new-advanced materials for use in the fields of solid state lasers and optoelectronic devises. 相似文献
80.
This work presents a fast method for the simultaneous separation and determination of glimepiride, glibenclamide, and two related substances by RP LC. The separation was performed on a Chromolith Performance (RP-18e, 100 mm x 4.6 mm) column. As mobile phase, a mixture of phosphate buffer pH 3, 7.4 mM, and ACN (55:45 v/v) was used. Column oven temperature was set to 30 degrees C. The total chromatographic run time was 80 s. This was achieved using a flow program from 5 to 9.9 mL/min. Precisions of the interday and the intraday assay for both retention times and peak areas for the four analyzed compounds were less than 1.2%. The method showed good linearity and recovery. The short analysis time makes the method very valuable for quality control and stability testing of drugs and their pharmaceutical preparations. 相似文献