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排序方式: 共有322条查询结果,搜索用时 15 毫秒
21.
Sherif R. Abdel-All Zeinab T. Abdel Shakour Dalia M. N. Abouhussein Enji Reda Thoraya F. Sallam Hala M. El-Hefnawy Azza R. Abdel-Monem 《Molecules (Basel, Switzerland)》2021,26(2)
The incorporation of cisplatin (CP) as a cytotoxic antineoplastic agent in most chemotherapeutic protocols is a challenge due to its toxic effect on testicular tissues. Natural compounds present a promising trend in research, so a new nutraceutical formulation (NCF) was designed to diminish CP spermatotoxicity. A combination of three nutraceutical materials, 250 mg Spirulina platensis powder (SP), 25 mg Tribulus terrestris L. extract (TT), and 100 mg fish oil (FO) were formulated in self-nanoemulsifying self-nanosuspension (SNESNS). SP was loaded into the optimized self-nanoemulsifying system (30% FO, 50% span 80/cremophor EL and 20% isopropanol) and mixed with TT aqueous solution to form SNESNS. For the SP, phytochemical profiling revealed the presence of valuable amounts of fatty acids (FAs), amino acids, flavonoids, polyphenols, vitamins, and minerals. Transmission electron microscopy (TEM) and particle size analysis confirmed the formation of nanoemulsion-based nanosuspension upon dilution. Method validation of the phytochemical constituents in NCF has been developed. Furthermore, NCF was biologically evaluated on male Wistar rats and revealed the improvement of spermatozoa, histopathological features, and biochemical markers over the CP and each ingredient group. Our findings suggest the potential of NCF with SNESNS as a delivery system against CP-induced testicular toxicity in male rats. 相似文献
22.
A convenient, practical, green, and environmentally friendly method was developed for the synthesis of biscoumarins and corresponding tetrakis products from the reaction of 4-hydroxycoumarin and various aldehydes. The bis-coumarins were synthesized in high yield under mild reaction conditions. Products were obtained in the presence of in situ prepared Fe(SD)3 [Iron(III) dodecyl sulfate] as a combined Lewis acid–surfactant catalyst (LASC) in water in short reaction times. Also, the antibacterial activity of compounds was screened against Pseudomonas aeruginosa and Escherichia coli as Gram-negative bacteria and Micrococcus luteus and Staphylococcus aureus as Gram-positive bacterial strains. Products 3g , 3k–l were most active than cefotaxime against E. coli and also compounds 3c and 3g were most active than cefotaxime against S. aureus. 相似文献
23.
Zeinab Abdeveiszadeh Siamak Noorizadeh 《International journal of quantum chemistry》2020,120(11):e26185
DFT calculations are performed to investigate the structure, stability, and nature of chemical bonding of some neutral noble gas insertion compounds containing a Xe-Xe bond; including HXeXeR, FXeXeR as well as RXeXeR (R = CN, NC, CCH, and BS). Geometry optimization of the considered molecules anticipate the existence of just four stable compounds (HXeXeCN, HXeXeNC, FXeXeCN, and FXeXeCCH); and rest of the molecules dissociate during the structural optimization. The results of NBO and AIM calculations show that a H(F)XeXeR molecule has a covalent H(F)-Xe bond in the H(F)XeXe+ fragment, which is bonded to R− mainly through columbic interaction. Thermodynamic study indicates that all of the considered unimolecular dissociation channels for decomposition of H(F)XeXeR molecules to neutral fragments are both exothermic and exorergic; but dissociation to ionic species (H(F)XeXe+ and R−) is endothermic. Also kinetic study of the most probable dissociation reaction shows that FXeXeR molecules are metastable with respect to the global minimum F-R + 2Xe. Therefore, FXeXeCN molecule is more kinetically protected against the decomposition reaction than the other molecules and its experimental detection is more likely. 相似文献
24.
Zeinab Akbarzadeh 《Green Chemistry Letters and Reviews》2020,13(2):141-154
ABSTRACT A novel mesoporous Al-SBA-15 modified by N,N'-(1,2-phenylene)bis(2-aminobenzamide) dichloro cobalt has been prepared and applied as a reusable catalyst in the 3-cinnamoyl coumarins synthesis via three-component reaction between benzaldehydes, salicylaldehydes and ethyl acetoacetate by the assist of ultrasonic irradiation. By using of the nanocatalyst and also ultrasound irradiation, the easiness and velocity of the abovementioned reaction were enhanced and an environment friendly condition was provided to synthesis of various 3-cinnamoyl coumarin compounds. The properties and structure of nanocatalyst have been specified by methods including powder X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), nitrogen adsorption–desorption analysis and scanning electronic microscopy (SEM). Superiority of this novel and viable method is due to mild reaction condition, short reaction times, high yields of 3-cinnamoyl coumarins, environmentally benign, recoverability of the CoCl2N,N'-(1,2-phenylene)bis(2-aminobenzamide)/Al-SBA-15 catalyst and reusability with important preservation in its catalytic activity. 相似文献
25.
The platinum(II) complex [PtMe2(bpy)] (bpy = 2,2′-bipyridine) reacted with a large excess of dihaloalkanes X(CH2)nX (n = 1, X = Cl; n = 4, X = Br) to form the platinum(IV) complexes [PtMe2X{(CH2)nX}(bpy)] (n = 1, X = Cl, 1a; n = 4, X = Br, 1b). The reaction of complexes 1a and 1b with SnBr2 resulted in insertion of SnBr2 into Pt–X (X = Cl, Br) bond to afford the trihalostannyl complexes [PtMe2(SnBr2X){(CH2)nX}(bpy)] (n = 1, X = Cl, 2a; n = 4, X = Br, 2b). The synthesis of such trihalostannylplatinum(IV) complexes is reported for the first time. The complex 2a was decomposed in CH2Cl2 solution and single crystals of [PtBr2(bpy)] (3a) were obtained. The X-ray structure determination of 3a revealed a new polymorphic form of [PtBr2(bpy)]. The molecules undergo a remarkable stacking along the b-axis to form a zigzag Pt?Pt?Pt chain containing both short (3.799 Å) and long (5.175 Å) Pt?Pt separations through the crystal. The crystal structure is compared to that of the yellow modification of [PtBr2(bpy)]. 相似文献
26.
Phase-controlled atom-photon entanglement in a three-level Λ-type closed-loop atomic system
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We study the entanglement of dressed atom and its spontaneous emission in a three-level Λ-type closed-loop atomic system in a multi-photon resonance condition and beyond it.It is shown that the von Neumann entropy in such a system is phase-dependent,and it can be controlled by either the intensity or relative phase of applied fields.It is demonstrated that for the special case of the Rabi frequency of applied fields,the system is disentangled.In addition,we take into account the effect of Doppler broadening on the entanglement and it is found that a suitable choice of laser propagation direction allows us to obtain the steady state degree of entanglement(DEM) even in the presence of the Doppler effect. 相似文献
27.
<正>4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component one-pot condensation of acetophe-none derivatives,aldehydes and urea in the presence of trimethylsilyl chloride and a catalytic amount of H_3PMo_(12)O_(40)under solvent-free conditions. 相似文献
28.
Oxidative coupling of methane over (Na2WO4+Mn or Ce)/SiO2 catalysts: In situ measurement of electrical conductivity
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Zeinab Gholipour Azim Malekzadeh Reza Hatami Yadollah Mortazavi Abasali Khodadadi 《天然气化学杂志》2010,19(1):35-42
The effects of manganese oxide or ceria promoters on the performance of Na2WO4/SiO2 catalysts for oxidative coupling of methane (OCM) are reported. The OCM reaction was performed in a continuous-flow microreactor at 800 ℃, atmospheric pressure and under GHSV = 13200 ml gC-1at h-1. Catalysts were characterized by in situ conductivity measurement, FT-IR spectroscopy, XRD, SEM and temperature programmed reduction analysis. Manganese oxide promoted Na2WO4/SiO2 is considered as one of the active and selective ca... 相似文献
29.
Chemical analysis of a marine-derived Streptomyces sp. (CMB-M0423) isolated from beach sand off Heron Island, Australia, yielded three new members of the rare pyrroloterpene biosynthetic structure class. Identified by detailed spectroscopic analysis as the first reported examples of naturally occurring 2-nitropyrroles, heronapyrroles A-C (1-3) displayed promising biological activity-with low to submicromolar IC(50) activity against Gram-positive bacteria but no cytotoxicity toward mammalian cell lines. 相似文献
30.
New and efficient multi-component methods have been developed for the synthesis of spirooxindoles in the presence of a catalytic amount of p-TSA as an inexpensive and available catalyst in EtOH under ultrasound irradiation. The method is simple, starts from readily accessible commercial starting materials, and provides biologically interesting products in good yields and short reaction times. 相似文献