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31.
This paper is concerned with iterative solution to general Sylvester-conjugate matrix equation of the form $\sum_{i = 1}^{s} A_{i}V + \sum_{j = 1}^{t} B_{j}W = \sum_{l = 1}^{m} E_{l}\overline{V}F_{l} + C$ . An iterative algorithm is established to solve this matrix equation. When this matrix equation is consistent, for any initial matrices, the solutions can be obtained within finite iterative steps in the absence of round off errors. Some lemmas and theorems are stated and proved where the iterative solutions are obtained. Finally, a numerical example is given to verify the effectiveness of the proposed algorithm.  相似文献   
32.
Today, cancer is considered as one of the major reasons of death in human beings worldwide. We reported herein the synthesis, anticancer activity, and in silico docking studies of a series of nine quinazolindione-based scaffolds bearing pyrimidine, pyridine, pyran, and pyrazole moieties ( 1 - 9 ) through Michael addition, Vilsmeier-Haack, Claisen-Schmidt, and nucleophilic addition reactions. The chemical structures of the newly prepared compounds were ascertained by means of their spectral analysis techniques like IR, 1H-nuclear magnetic resonance (NMR), 13C-NMR, mass spectroscopy, and elemental analysis. This work was conducted to investigate the implication of Rho7 protein in breast and hepatocellular cancer cells aggressively. MCF-7 and HepG2 cells have been selected as models for the effect of protein expression on breast and hepatocellular cancers cell growth. All prepared compounds were biologically evaluated for their antiproliferative efficacy on hepatic cancer cell lines (HepG2) and breast cancer cell lines (MCF-7); also, their effects on normal cell lines (BALB/3T3) were studied. Moreover, in silico molecular docking studies were studied for the compounds against the binding site of Homo sapiens Rho7 protein. The pharmacokinetic properties of the newer compounds were also evaluated using various computational tools. The compounds showed interesting interactions with satisfactory docking scores to the target Rho7; thus, they may act as promising potent drug candidates against cancer.  相似文献   
33.
Novel triazoloquinoxaline-pyrazole hybrids have been developed and synthesized. All derivatives' anticancer activity has been evaluated using Sulforhodamine-B (SRB) assay for cancer cell lines MCF-7, HepG-2, and HCT-116. Compound 12b was 2-fold more cytotoxic than Doxorubicin, while 12a , c demonstrated comparable cytotoxicity to the reference Doxorubicin. Further investigations on the most active derivatives 12a-c were done to study their inhibitory activity on two EGFR subtypes wild EGFR and mutant EGFR (L858R) tyrosine kinases in MCF-7 cell lines. Compound 12b exhibited potent inhibitory activity toward wild EGFR (IC50: 0.98 μM) when compared to Gefitinib (IC50:18.07 μM). 12b also possessed a marked inhibition against mutant EGFR (L858R-TK) exhibiting (IC50:27.45 μM) in comparison to Lapatinib (IC50: 61.06 μM). Compound 12b improved the active Caspase-3 value and the BAX/Bcl-2 reference. Furthermore, 12b showed G2/M cell cycle arrest induced apoptosis in cell line MCF-7. In addition, the most active derivatives have been orally bioavailable as shown in the in silico determination of the ADME characters. The binding pattern of compound 12b was also studied by molecular docking.  相似文献   
34.
This study involves the synthesis and anticonvulsant evaluation of 1‐ethyl‐3‐hydrazinylquinoxaline‐2‐(1H)‐one ( 8 ), its chemical confirmations 9 and 10 and certain (1,2,4) triazolo(4,3‐a)quinoxalin‐4(5H)‐one compounds 11 , 12 , 13 , 13a , 13b , 13c , 13d , 13e , 13f , 14 , 15 , 16 . The structure of the synthesized compounds was confirmed chemically by elemental analyses and spectral data (IR, 1H NMR, 13C NMR, and Mass). Docking studies were preformed to all of the synthesized compounds to predict, in a qualitative way, the anticonvulsant activity of the proposed compounds. There is a promising correlation between the results of molecular modeling and the anticonvulsant activity of the synthesized compounds. The highest fitting value was noticed for compounds 9 and 10 , which showed the highest anticonvulsant activity.  相似文献   
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36.
We are concerned with the following: If k is a quadratic field and N a cyclic unramified extension of degree qn over k, q a prime number, determine N explicitely via a primitive element , i.e., N=k(), in the spirit of Helmut Hasse [3]. We propose a method which determines these extensions, once we are able to specify the arithmetic of a certain field . To explicit our method, we construct the Hilbert fields of (226) and (646).  相似文献   
37.
The present work reports the self-healing performance of the epoxy based polymeric nanocomposite coatings containing different concentrations (1 and 3 wt%) of talc nanoparticles (TNPs) modified with sodium nitrate (NaNO3), and a fixed amount (5 wt%) of urea-formaldehyde microcapsules (UFMCs) encapsulated with linseed oil (LO). The polymeric nanocomposites were developed, coated on polished steel substrates, and their structural, thermal, and self-healing characteristics were investigated using various techniques. The successful loading (~wt 10%) of NaNO3 into TNPs, which can be ascribed to the involvement of physio-chemical adsorption mechanism, is validated and proceeds without altering the TNPs parent lamellae structure. The performed tests elucidated that the self-release of the corrosion inhibitor (NaNO3) from TNPs is sensitive to the pH of the solution and immersion time. In addition, the release of the linseed oil (self-healing agent) from UFMCs in response to the external damage was found to be a time-dependent process. The superior self-healing and corrosion inhibition performance of the protective polymeric nanocomposites coatings containing 3 wt% TNPs and UFMCs/LO are proven using the electrochemical impedance spectroscopy (EIS) studies. A careful selection of smart carriers, inhibitor, and self-healing agent compatible with polymeric matrix has enabled to attain decent self-healing and convincing corrosion inhibition efficiency of 99.9% and 99.5%, respectively, for polymeric nanocomposites coatings containing 3 and 1 wt% TNPs, making them attractive for many industrial applications.  相似文献   
38.
Thiazoles are important scaffolds in organic chemistry. Biosynthesis of thiazoles is considered to be an excellent target for the design of novel classes of therapeutic agents. In this study, a new series of 2-ethylidenehydrazono-5-arylazothiazoles 5a–d and 2-ethylidenehydrazono-5-arylazo- thiazolones 8a–d were synthesized via the cyclocondensation reaction of the appropriate hydrazonyl halides 4a–d and 7a–d with ethylidene thiosemicarbazide 3, respectively. Furthermore, the thiosemicarbazide derivative 3 was reacted with different bromoacetyl compounds 10–12 to afford the respective thiazole derivatives 13–15. Chemical composition of the novel derivatives was established on bases of their spectral data (FTIR, 1H-NMR, 13C-NMR and mass spectrometry) and microanalytical data. The newly synthesized derivatives were screened for their in vitro anti-hepatic cancer potency using an MTT assay. Moreover, an in silico technique was used to assess the interaction modes of the compounds with the active site of Rho6 protein. The docking studies of the target Rho6 with the newly synthesized fourteen compounds showed good docking scores with acceptable binding interactions. The presented results revealed that the newly synthesized compounds exhibited promising inhibition activity against hepatic cancer cell lines (HepG2).  相似文献   
39.
2-azido-1H-benzo[d]imidazole derivatives 1a,b were reacted with a β-ketoester such as acetylacetone in the presence of sodium ethoxide to obtain the desired molecules 2a,b. The latter acted as a key molecule for the synthesis of new carbazone derivatives 4a,b that were submitted to react with 2-oxo-N-phenyl-2-(phenylamino)acetohydrazonoyl chloride to obtain the target thiadiazole derivatives 6a,b. The structures of the newly synthesized compounds were inferred from correct spectral and microanalytical data. Moreover, the newly prepared compounds were subjected to molecular docking studies with DNA gyrase B and exhibited binding energy that extended from −9.8 to −6.4 kcal/mol, which confirmed their excellent potency. The compounds 6a,b were found to be with the minimum binding energy (−9.7 and −9.8 kcal/mol) as compared to the standard drug ciprofloxacin (−7.4 kcal/mol) against the target enzyme DNA gyrase B. In addition, the newly synthesized compounds were also examined and screened for their in vitro antimicrobial activity against pathogenic microorganisms Staphylococcus aureus, E. coli, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans. Among the newly synthesized molecules, significant antimicrobial activity against all the tested microorganisms was obtained for the compounds 6a,b. The in silico and in vitro findings showed that compounds 6a,b were the most active against bacterial strains, and could serve as potential antimicrobial agents.  相似文献   
40.
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