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排序方式: 共有192条查询结果,搜索用时 15 毫秒
11.
Ali Raza Hala A. Hejazi Sami Ullah Khan M. Ijaz Khan Kamel Smida Iskander Tlili 《印度化学会志》2022,99(7):100568
In this investigation, a mixed convective nanoparticles fluid flow over an inclined plate is deliberated. The effects of slip boundary wall and magnetic field are also considered. The dimensionless governing system for the considered problem is attained by implementing recent definitions of fractional derivatives (FD). The generalized solution is obtained through the Laplace Transformation Scheme (LTS) for the momentum and thermal expressions. To improve the novelty and to demonstrate some more physical perception of the stated research work, some remarkable special cases of velocity distribution through CF and AB-fractional derivative concept are addressed, whose daily life implication is well known in the existing literature. Moreover, to evaluate the physical interest of the stated problem, the outcomes of the obtained system graphical illustrations are made by utilizing MATHEMATICA. As a result, we concluded that the aluminium oxide nanoparticles show more decaying behavior as compared to titanium oxide nanoparticles for temperature and velocity profile. Furthermore, both fields i.e., momentum and thermal distributions are increased with the help of rising estimations parameter. Current results report novel applications in enhancement of heat transfer, thermal engineering, chemical processes, engineering and electronics devices, solar systems, extrusion processes, fission reactions etc. 相似文献
12.
Karim Samy El-Said Shaimaa Hussein Barakat M. Alrashdi Heba A. Mahmoud Mahrous A. Ibrahim Mohamed Elbakry Hala El-Tantawy Doaa Ibrahim Kabil Sabry A. El-Naggar 《Molecules (Basel, Switzerland)》2022,27(2)
Heavy metals intoxication causes several health problems that necessitate finding new protective and therapeutic approaches. This study aimed to evaluate the impact of Musa sp. leaves extract (MLE) on hepato-renal toxicities induced by cadmium (Cd) in male mice. The phytochemical screening, metal chelating activity (MCA), and the median lethal dose (LD50) of MLE were determined. Fifty CD-1 male mice were used and intraperitoneally (i.p.) injected with MLE (1000 to 5000 mg/kg b.wt) for MLE LD50 determination. Another 50 mice were used for evaluating the effect of MLE on Cd toxicity. Blood samples were collected for hematological, liver, and kidney functions assessments. Liver tissue homogenates were used for determination of oxidant/antioxidant parameters. Liver and kidney tissues were harvested for histopathological and molecular investigations. MLE showed potent in vitro antioxidant activities. The MCA and LD50 of the MLE were 75 µg/mL and 3000 mg/kg b.wt, respectively. MLE showed beneficial therapeutic activity against hepato-renal toxicities in Cd-intoxicated mice, evidenced by improving the hematological, biochemical, histopathological, and molecular alterations. 相似文献
13.
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
14.
Zeinab El Rashed Giulio Lupidi Elena Grasselli Laura Canesi Hala Khalifeh Ilaria Demori 《Molecules (Basel, Switzerland)》2021,26(15)
Fucoidan is a fucose-rich sulfated polysaccharide typically found in the cell wall of marine algae but also recently isolated from terrestrial sources. Due to a variety of biological activities, including antioxidant properties, fucoidan exhibits an attractive therapeutic potential against a wide array of metabolic diseases associated with oxidative stress. We used FTIR, 1H NMR and 13C NMR spectroscopy to investigate the structural features of a fucoidan fraction extracted from the brown alga Cystoseira compressa (CYS). The antioxidant potential of CYS was measured by DPPH, ABTS and FRAP assays, which revealed a radical scavenging capacity that was confirmed in in vitro cellular models of hepatic and endothelial cells. The same antioxidant effects were observed for another fucoidan fraction previously identified in the terrestrial tree Eucalyptus globulus (EUC). Moreover, in hepatic cells, CYS and EUC exhibited a significant antisteatotic action, being able to reduce intracellular triglyceride content through the regulation of key genes of hepatic lipid metabolism. EUC exerted stronger antioxidant and antisteatotic effects as compared to CYS, suggesting that both marine and terrestrial sources should be considered for fucoidan extraction and therapeutic applications. 相似文献
15.
Hala Samaha Nathalie Chahine Anatoly Petrovich Sobolev Luigi Menghini Hassane Makhlouf 《Molecules (Basel, Switzerland)》2021,26(16)
Despite the beneficial health properties shown by Lebanese saffron, its qualitative and quantitative composition has never been investigated before. In the present study, NMR spectroscopy, together with antioxidant activity assays, were applied to evaluate the chemical composition of saffron samples of different geographical origins (Lebanon, Italy, Iran, and India) and to categorize the Lebanese saffron for the first time. The distinction between Lebanese saffron and that produced in other countries was attributed to its higher linolenic and linoleic fatty acids, glucose and picrocrocin contents. Moreover, spices produced in three different regions of the Lebanese territory have been clearly differentiated. Saffron cultivated in the Qaa region displayed a high glucose, fatty acids and polyphenols content, whereas Hermel saffron exhibited the largest rate of picrocrocin and glycosylated carotenoids. Finally, samples from Baalbeck showed lower rates for the majority of metabolites. Moreover, Lebanese saffron showed a high antioxidant activity in ABTS and DPPH assays. A low dose of saffron extract (10 µg/mL) inhibited the growth of human lung adenocarcinoma cells, probably due to the high polyphenolic content. This study highlights the quality and peculiarity of Lebanese saffron cultivated in Northern Beqaa district and allows for a good discrimination between spices produced in relatively close territory. 相似文献
16.
Mohamed A. Salem Mohamed H. Helal Moustafa A. Gouda Hala H. Abd EL-Gawad Marwa A. M. Shehab Abeer El-Khalafawy 《合成通讯》2019,49(14):1750-1776
The development of new synthetic routes towards pyrazolo[1,5-a]pyrimidines for their biological and medicinal exploration is an attractive area for researchers. This review focuses on various synthetic routes developed in the last decade for the synthesis of differently substituted pyrazolo[1,5-a]pyrimidines by a broad range of organic reactions by means of 5-aminopyrazole as a precursor. 相似文献
17.
JPC – Journal of Planar Chromatography – Modern TLC - The merits of chemometrics in categorizing different Egyptian olive chemovarieties based on their compositional integrity were... 相似文献
18.
Ahmed H. Ragab Hala S. Hussein Inas A. Ahmed Khamael M. Abualnaja Najla AlMasoud 《Molecules (Basel, Switzerland)》2021,26(17)
Based on the adsorption performance of a porous nanocomposite with limestone (LS), activated carbon (AC) and sodium alginate (SG), a unique, multifunctional LS–AC–SG nanocomposite absorbent was designed and prepared for extracting antibiotics and drugs from aqueous solutions. The composite exhibited the following advantages: quick and simple to prepare, multifunctionality and high efficiency. Amoxicillin (AMX) and diclofenac (DCF) were chosen as the conventional antibiotic and the drug, respectively. The prepared nanocomposite’s physicochemical characteristics were calculated through numerous characterization methods. The structure of the surface was made up of interconnected pores that can easily confine pollutants. The surface area was measured to be 27.85 m2/g through BET analysis. The results show that the maximum absorption capacity of amoxicillin and diclofenac was 99.6% and 98.4%, respectively, at a contact time of 40 min. The maximum removal of amoxicillin and diclofenac was reached at pH = 2. Adsorption analysis revealed that adsorption isotherm and kinetic data matched the pseudo-first-order kinetic and the Langmuir isotherm models. The results imply that the synthesized nanocomposites have the capacity to remove amoxicillin (AMX) and diclofenac (DCF) from aqueous solutions. 相似文献
19.
Omar A. Fathalla Neama A. Mohamed Walaa S. El-Serwy Hala F. AbdelHamid Sherein I. Abd El-Moez Abdel-mohsen M. Soliman 《Research on Chemical Intermediates》2013,39(3):821-841
Starting from the reaction of ethyl cyanoacetate with thiourea and the appropriate aldehydes, a series of new pyrimidine derivatives were prepared. Ten selected pyrimidine derivatives were subjected to a screening system for the investigation of their antitumor potency against liver (HEPG2) cell line. The antitumor activity results indicated that most of the selected pyrimidine derivatives showed moderate growth inhibition activity against the tested cell line, but with varying intensities in comparison to the known anticancer drugs: 5-fluorouracil and doxorubicin. Some of the synthesized compounds were also tested for their antimicrobial activity against bacteria as well as fungal isolates. 相似文献
20.
Ayad M. R. Raauf Rafah F. Al-Smaism Khalida A. Thejeel Hala Ayad M. Rasheed 《Natural product research》2019,33(9):1277-1283
New compounds of trimethoprim heterocyclic derivatives were synthesized. These compounds were synthesized through the condensation reaction between trimethoprim with bromoacetic acid to yield compound 1. Several Schiff bases 2–7 have been synthesized by the condensation different aromatic aldehydes with compound 1. Compound 8 were formed from the reaction of sodium nitrite and acetyl acetone in presence of conc. hydrogen chloride to obtain the hydrazono derivative; then, Cyclocondensation of compound 8 with hydrazine hydrate, phenyl hydrazine and dinitrophenyl hydrazine respectively to yield compounds 9–11 in ethanol affording the pyrazoline derivatives. This work involves the synthesis of some 1,2,3-Triazoles derived from compound 1 by the action of sodium azide on the diazonium chloride salt to yield 5-azido-8-(3,4,5-trimethoxybenzyl)imidazo[1,2-c]pyrimidin-3(2H)-one 12. Finally, by reaction of 12 with acetyl acetone and ethyacetoacetate; respectively in sodium ethoxide/ethanol as a solvent to form compounds 13, 14. The structures of the compounds 1–14 were characterized by elemental analysis, spectral data and antimicrobial evaluation of the some newly synthesized compounds and found that the synthesized compounds are active against tested Gram positive and Gram negative bacteria like Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Proteus. 相似文献