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排序方式: 共有479条查询结果,搜索用时 15 毫秒
381.
Hatem A. Abuelizz Ahmed H. Bakheit Mohamed Marzouk Mohamed M. Abdellatif Rashad Al-Salahi 《Molecules (Basel, Switzerland)》2022,27(11)
The cyclic anhydrides are broadly employed in several fields, such as the chemical, plastic, agrochemical, and pharmaceutical industries. This study describes the chemical reactivity of 4,5-dichlorophthalic anhydride towards several nucleophiles, including thiosemicarbazide and different amines, to produce the carboxylic acid derivatives resulting from anhydride’s opening, namely, phthalimide and dicarboxylic acid (1–12) products. Their chemical structures are confirmed by NMR, IR and MS spectra analyses. Density–functional theory (DFT) studies are performed using (DFT/B3LYP) with the 6-311G(d, p) basis sets to recognize different chemical and physical features of the target compounds. 相似文献
382.
Ali A. Rabaan Abbas Al Mutair Hawra Albayat Jawaher Alotaibi Tarek Sulaiman Mohammed Aljeldah Basim R. Al Shammari Amal H. Alfaraj Mona A. Al Fares Sara Alwarthan Abdulwahab Z. Binjomah Mohammed S. Alzahrani Hatem M. Alhani Mohammed S. Almogbel Abdulmonem A. Abuzaid Ghaya Alqurainees Fatimah Al Ibrahim Ali H. Alhaddad Mubarak Alfaresi Nadira Al-baghli Saad Alhumaid 《Molecules (Basel, Switzerland)》2022,27(20)
Mycobacterium tuberculosis (Mtb), an acid-fast bacillus that causes Tuberculosis (TB), is a pathogen that caused 1.5 million deaths in 2020. As per WHO estimates, another 4.1 million people are suffering from latent TB, either asymptomatic or not diagnosed, and the frequency of drug resistance is increasing due to intrinsically linked factors from both host and bacterium. For instance, poor access to TB diagnosis and reduced treatment in the era of the COVID-19 pandemic has resulted in more TB deaths and an 18% reduction in newly diagnosed cases of TB. Additionally, the detection of Mtb isolates exhibiting resistance to multiple drugs (MDR, XDR, and TDR) has complicated the scenario in the pathogen’s favour. Moreover, the conventional methods to detect drug resistance may miss mutations, making it challenging to decide on the treatment regimen. However, owing to collaborative initiatives, the last two decades have witnessed several advancements in both the detection methods and drug discovery against drug-resistant isolates. The majority of them belong to nucleic acid detection techniques. In this review, we highlight and summarize the molecular mechanism underlying drug resistance in Mtb, the recent advancements in resistance detection methods, and the newer drugs used against drug-resistant TB. 相似文献
383.
Amira M. G. Darwish Aida A. Abd El-Wahed Mohamed G. Shehata Hesham R. El-Seedi Saad H. D. Masry Shaden A. M. Khalifa Hatem M. Mahfouz Sobhy A. El-Sohaimy 《Molecules (Basel, Switzerland)》2023,28(1)
Honeybee products, as multicomponent substances, have been a focus of great interest. The present work aimed to perform the nutritional and chemical profiling and biochemical characterization of bee pollen (BP), bee bread (BB), and royal jelly (RJ) and study their applications in the fortification of functional fermented dairy products. Their effects on starter cultures and the physicochemical and sensorial quality of products were monitored. A molecular networking analysis identified a total of 46 compounds in the three bee products that could be potential medicines, including flavonoids, fatty acids, and peptides. BB showed the highest protein and sugar contents (22.57 and 26.78 g/100 g), which cover 45.14 and 53.56% of their daily values (DVs), with considerable amounts of the essential amino acids threonine and lysine (59.50 and 42.03%). BP, BB, and RJ can be considered sources of iron, as 100 g can cover 141, 198.5, and 94.94% of DV%, respectively. BP was revealed to have the highest phenolic and flavonoid contents (105.68 and 43.91 µg/g) and showed a synergetic effect when mixed with RJ, resulting in increased antioxidant activity, while BB showed a synergetic effect when mixed with RJ in terms of both antioxidant and proteolytic powers (IC50 7.54, 11.55, 12.15, 12.50, and 12.65 cP compared to the control (10.55 cP)), reflecting their organoleptic properties and highlighting these health-oriented products as promising natural products for human health care. 相似文献
384.
Dina M. El-Kersh Rania F. Abou El-Ezz Marwa Fouad Mohamed A. Farag 《Molecules (Basel, Switzerland)》2022,27(17)
Acylated flavonoids are widely distributed natural metabolites in medicinal plants and foods with several health attributes. A large diversity of chemical structures of acylated flavonoids with interesting biological effects was reported from several plant species. Of these, 123 compounds with potential antimicrobial, antiparasitic, anti-inflammatory, anti-nociceptive, analgesic, and anti-complementary effects were selected from several databases including SCI-Finder, Scopus, Google Scholar, Science Direct, PubMed, and others. Some selected reported biologically active flavonoids were docked in the active binding sites of some natural enzymes, namely acetylcholinesterase, butyrylcholinesterase, α-amylase, α-glucosidase, aldose reductase, and HIV integrase, in an attempt to underline the key interactions that might be responsible for their biological activities. 相似文献
385.
With a view to creating a specific unique chip, its wearable, flexible and conductor.utilizing conventional physical methods like grafting and assembling metals (silver, copper, and gallium indium alloy) on graphene as composite, then immersed inside PDMS matrix. However, there is an incompatibility between liquid gallium and graphene sheet. So we used the abridge of metallic nanoparticles as silver and copper as a boundary barrier to its different charges to maximize interfacial surface interaction in between amorphous carbon and liquid gallium. to evaluate the chip conduct during the fabrication process we utilize various characterization such as electrochemical EIS and CVT to justify conductivity besides electrochemical reaction and oxidation and reduction, addition to measure the dielectric constant (?) of a composite at a different range of frequencies which is equal to 3.73 compared to PDMS 2.69.moreover its thermal stability (DSC) of prepared composite and tensile stress as an inductor for enforcement and enhancement physical properties, as well as, surface Morphology techniques characterize using TEM IR, and UV absorption. 相似文献
386.
387.
Bakr F. Abdel-Wahab Hatem A. Abdel-Aziz Essam M. Ahmed 《Monatshefte für Chemie / Chemical Monthly》2009,140(6):601-605
Abstract Potassium hydrazinecarbodithioate were prepared by treatment of acid hydrazides with carbon disulfide in the presence of potassium
hydroxide. Reaction of this potassium salt with hydrazine hydrate, phenacyl bromide, or hydrazonoyl chlorides afforded 1,2,4-triazole,
1,3-thiazole, and 1,3,4-thiadiazoles. Reaction of 1,2,4-triazole with phenacyl bromide or hydrazonoyl chlorides afforded the
corresponding 1,2,4-triazolo[3,4-b][1, 3, 4]-thiadiazines. All these new compounds were screened for antibacterial and antifungal activity. Some had promising
activity.
Graphical abstract
相似文献
388.
389.
Djaafar Zouache Abdelouahab Moussaoui Fouad Ben Abdelaziz 《European Journal of Operational Research》2018,264(1):74-88
We propose a novel cooperative swarm intelligence algorithm to solve multi-objective discrete optimization problems (MODP). Our algorithm combines a firefly algorithm (FA) and a particle swarm optimization (PSO). Basically, we address three main points: the effect of FA and PSO cooperation on the exploration of the search space, the discretization of the two algorithms using a transfer function, and finally, the use of the epsilon dominance relation to manage the size of the external archive and to guarantee the convergence and the diversity of Pareto optimal solutions.We compared the results of our algorithm with the results of five well-known meta-heuristics on nine multi-objective knapsack problem benchmarks. The experiments show clearly the ability of our algorithm to provide a better spread of solutions with a better convergence behavior. 相似文献
390.
A compromise solution for the multiobjective stochastic linear programming under partial uncertainty
This paper solves the multiobjective stochastic linear program with partially known probability. We address the case where the probability distribution is defined by crisp inequalities. We propose a chance constrained approach and a compromise programming approach to transform the multiobjective stochastic linear program with linear partial information on probability distribution into its equivalent uniobjective problem. The resulting program is then solved using the modified L-shaped method. We illustrate our results by an example. 相似文献