排序方式: 共有194条查询结果,搜索用时 281 毫秒
181.
Amr A. E. Abdalla M. M. Essaouy S. A. Areef M. M. H. Elgamal M. H. Nassear T. A. Haschich A. E. 《Russian Journal of General Chemistry》2017,87(8):1826-1833
Russian Journal of General Chemistry - A number of substituted 4-methoxy-7-methyl-6-(substituted methyl)-5-oxo-5H-furo[3,2-g]-chromene-9-sulfonates 3a–3f and 4a–4c were synthesized.... 相似文献
182.
Biocompatible polyacrylic acid functionalized CdSe/Cu quantum dot conjugates were synthesized to be used for biomolecules detection. The study results demonstrate the conjugation of the 2.5-3 nm QD with gram negative bacteria with a low detection limit of 28 cfu/ml. The photoluminescence (PL) intensity was correlated to bacterial count, cellular proteins and exopolysaccharides in the tested samples. Confocal Scanning Laser Microscopy (CSLM) images showed significant QD uptake within the cells, both cytoplasm and DNA were the predominant targeted biomolecules, higher fluorescent uptake was shown in gram negative bacteria than that observed for gram positive bacteria. Moreover, PL showed that there was a distinction between live and dead cells as well as gram negative and gram positive cells. Cell viability was not affected even after 6 days (100% viability) rendering it a non-toxic QD. The method is simple and is performed in a single step within approximately 10 min as compared to multi-step protocols for classical microbial count or fluorescent dye staining. All the above results indicate that the CdSe/Cu-PAA QDs are suitable for biomolecule detection, bio-labeling and bioimaging applications. 相似文献
183.
Amr A. Yakout Medhat A. Shaker Khalid Z. Elwakeel Wael Alshitari 《Journal of Dispersion Science and Technology》2019,40(5):707-715
Lauryl sulfate is utilized to functionalize magnetic graphene oxide (MGOLS) for fast removal of methylene blue (MB) using batch sorption experiments. The effects of different analytical parameters including medium pH, equilibration time, MGOLS dosage, initial MB concentration and temperature on the % MB removal are investigated. Among different isotherm and kinetic models, the experimental data were best fitted to the Langmuir and pseudo-second-order rate equations. The maximum Langmuir loading capacity reaches 624.42?mg g?1 for MGOLS under optimal conditions. Sorption kinetic of MGOLS is very fast: Approximately 96% of dye extraction was recorded within the first 2?minutes of this sorption process. The sorption mechanism is proposed and the feasibility, thermic and entropic characteristics were evaluated. Sorption and desorption performances of MGOLS are maintained almost constant over five cycles of sorption/desorption. The results concluded MGOLS as an efficient extractor for fast and feasible recovery of MB from aqueous matrices. 相似文献
184.
Amr Farouk Mohamed Mohsen Hatem Ali Hamdy Shaaban Najla Albaridi 《Molecules (Basel, Switzerland)》2021,26(14)
A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and β-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical–scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by β-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry. 相似文献
185.
Saraa Abu-Melha Sobhi M. Gomha Amr S. Abouzied Mastoura M. Edrees Ahmed S. Abo Dena Zeinab A. Muhammad 《Molecules (Basel, Switzerland)》2021,26(14)
Pyridazine and thiazole derivatives have various biological activities such as antimicrobial, analgesic, anticancer, anticonvulsant, antitubercular and other anticipated biological properties. Chitosan can be used as heterogeneous phase transfer basic biocatalyst in heterocyclic syntheses. Novel 1-thiazolyl-pyridazinedione derivatives were prepared via multicomponent synthesis under microwave irradiation as ecofriendly energy source and using the eco-friendly naturally occurring chitosan basic catalyst with high/efficient yields and short reaction time. All the prepared compounds were fully characterized by spectroscopic methods, and their in vitro biological activities were investigated. The obtained results were compared with those of standard antibacterial/antifungal agents. DFT calculations and molecular docking studies were used to investigate the electronic properties and molecular interactions with specific microbial receptors. 相似文献
186.
The global economic crisis has a significant impact on healthcare resource provision worldwide. The management of limited healthcare resources is further challenged by the high level of uncertainty in demand, which can lead to unbalanced utilization of the available resources and a potential deterioration of patient satisfaction in terms of longer waiting times and perceived reduced quality of services. Therefore, healthcare managers require timely and accurate tools to optimize resource utility in a complex and ever-changing patient care process. An interactive simulation-based decision support framework is presented in this paper for healthcare process improvement. Complexity and different levels of variability within the process are incorporated into the process modeling phase, followed by developing a simulation model to examine the impact of potential alternatives. As a performance management tool, balanced scorecard (BSC) is incorporated within the framework to support continual and sustainable improvement by using strategic-linked performance measures and actions. These actions are evaluated by the simulation model developed, whilst the trade-off between objectives, though somewhat conflicting, is analysed by a preference model. The preference model is designed in an interactive and iterative process considering decision makers preferences regarding the selected key performance indicators (KPIs). A detailed implementation of the framework is demonstrated on an emergency department (ED) of an adult teaching hospital in north Dublin, Ireland. The results show that the unblocking of ED outflows by in-patient bed management is more effective than increasing only the ED physical capacity or the ED workforce. 相似文献
187.
Said A. S. Ghozlan Mohammed A. Al‐Omar Abd El‐Galil E. Amr Korany A. Ali Ahmed A. Abd El‐Wahab 《Journal of heterocyclic chemistry》2011,48(5):1103-1110
In this work, we report on the synthesis and preliminary biological activity screening of several heterocyclic derivatives 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 10a , 10b , 11 , 11a , 11b , 12 , 12a , 12b , 13 , 13a , 13b , 14 , 15 based on N2′,N6′‐diphenylthiosemi‐carbazide pyridine‐2,6‐dicarbohydrazide 2 , which has been obtained from the corresponding dihydrazide 1 . The biological screening showed that many of these compounds have good antimicrobial activities. The structure of the new compounds has been established on the bases of chemical and spectroscopic evidences. J. Heterocyclic Chem., (2011). 相似文献
188.
Nagy M. Khalifa Mostafa M. Ramla Abd El-Galil E. Amr Mohamed M. Abdulla 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3046-3062
A series of some new acetylated S-glycosides of pyridine-2-thione derivatives, including D-glucose, D-galactose, D-xylose and L-arabinose derivatives were synthesized. Oxidation of some formed S-glycosides derivatives with H2O2 afforded the corresponding sulfones. S-Alkylation of pyridine-2-thione derivatives was performed to furnish the S-acyclo deazauridine derivatives. The entire tested compound showed potent anti-inflammatory activity were potent against edema and in the same time inhibited the prostaglandine formation. It is work mention that all the tested compounds showed high safety margin. The structures of the new synthesized compounds have been proved by IR, 1 HNMR, mass spectra and elemental analysis. 相似文献
189.
In this work, a novel series of 9-amino-7-aryl-11-imino-2,4,8,10-tetraazaspiro[5.5]undeca-7,9-diene-1,3,5-triones 3a-l was synthesized via the treatment of cyanoguanidine 1 with respective arylidene barbituric acids 2a-l in dry pyridine. The products were evaluated for in vitro antibacterial activity against Bacillus cereus (+G), Staphylococcus aureus (+G), Pseudomonas aeruginosa (−G) and Escherichia coli (−G). The results showed that some of the tested products are promising antibacterial drugs. 相似文献
190.
Amr Amin Aaminah Farrukh Chandraprabha Murali Akbar Soleimani Franoise Praz Grazia Graziani Hassan Brim Hassan Ashktorab 《Molecules (Basel, Switzerland)》2021,26(13)
Background: Colorectal cancer (CRC) is one of the most common cancers worldwide. One of its subtypes is associated with defective mismatch repair (dMMR) genes. Saffron has many potentially protective roles against colon malignancy. However, these roles in the context of dMMR tumors have not been explored. In this study, we aimed to investigate the effects of saffron and its constituents in CRC cell lines with dMMR. Methods: Saffron crude extracts and specific compounds (safranal and crocin) were used in the human colorectal cancer cell lines HCT116, HCT116+3 (inserted MLH1), HCT116+5 (inserted MSH3), and HCT116+3+5 (inserted MLH1 and MSH3). CDC25b, p-H2AX, TPDP1, and GAPDH were analyzed by Western blot. Proliferation and cytotoxicity were analyzed by MTT. The scratch wound assay was also performed. Results: Saffron crude extracts restricted (up to 70%) the proliferation in colon cells with deficient MMR (HCT116) compared to proficient MMR. The wound healing assay indicates that deficient MMR cells are doing better (up to 90%) than proficient MMR cells when treated with saffron. CDC25b and TDP1 downregulated (up to 20-fold) in proficient MMR cells compared to deficient MMR cells, while p.H2AX was significantly upregulated in both cell types, particularly at >10 mg/mL saffron in a concentration-dependent manner. The reduction in cellular proliferation was accompanied with upregulation of caspase 3 and 7. The major active saffron compounds, safranal and crocin reproduced most of the saffron crude extracts’ effects. Conclusions: Saffron’s anti-proliferative effect is significant in cells with deficient MMR. This novel effect may have therapeutic implications and benefits for MSI CRC patients who are generally not recommended for the 5-fluorouracil-based treatment. 相似文献