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81.
Both members of the aldo-keto reductases (AKRs) family, AKR1B1 and AKR1B10, are over-expressed in various type of cancer, making them potential targets for inflammation-mediated cancers such as colon, lung, breast, and prostate cancers. This is the first comprehensive study which focused on the identification of phenylcarbamoylazinane-1, 2,4-triazole amides (7a–o) as the inhibitors of aldo-keto reductases (AKR1B1, AKR1B10) via detailed computational analysis. Firstly, the stability and reactivity of compounds were determined by using the Guassian09 programme in which the density functional theory (DFT) calculations were performed by using the B3LYP/SVP level. Among all the derivatives, the 7d, 7e, 7f, 7h, 7j, 7k, and 7m were found chemically reactive. Then the binding interactions of the optimized compounds within the active pocket of the selected targets were carried out by using molecular docking software: AutoDock tools and Molecular operation environment (MOE) software, and during analysis, the Autodock (academic software) results were found to be reproducible, suggesting this software is best over the MOE (commercial software). The results were found in correlation with the DFT results, suggesting 7d as the best inhibitor of AKR1B1 with the energy value of −49.40 kJ/mol and 7f as the best inhibitor of AKR1B10 with the energy value of −52.84 kJ/mol. The other potent compounds also showed comparable binding energies. The best inhibitors of both targets were validated by the molecular dynamics simulation studies where the root mean square value of <2 along with the other physicochemical properties, hydrogen bond interactions, and binding energies were observed. Furthermore, the anticancer potential of the potent compounds was confirmed by cell viability (MTT) assay. The studied compounds fall into the category of drug-like properties and also supported by physicochemical and pharmacological ADMET properties. It can be suggested that the further synthesis of derivatives of 7d and 7f may lead to the potential drug-like molecules for the treatment of colon cancer associated with the aberrant expression of either AKR1B1 or AKR1B10 and other associated malignancies.  相似文献   
82.
Triazole-based thiosemicarbazone derivatives (6a–u) were synthesized then characterized by spectroscopic techniques, such as 1HNMR and 13CNMR and HRMS (ESI). Newly synthesized derivatives were screened in vitro for inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. All derivatives (except 6c and 6d, which were found to be completely inactive) demonstrated moderate to good inhibitory effects ranging from 0.10 ± 0.050 to 12.20 ± 0.30 µM (for AChE) and 0.20 ± 0.10 to 14.10 ± 0.40 µM (for BuChE). The analogue 6i (IC50 = 0.10 ± 0.050 for AChE and IC50 = 0.20 ± 0.050 µM for BuChE), which had di-substitutions (2-nitro, 3-hydroxy groups) at ring B and tri-substitutions (2-nitro, 4,5-dichloro groups) at ring C, and analogue 6b (IC50 = 0.20 ± 0.10 µM for AChE and IC50 = 0.30 ± 0.10 µM for BuChE), which had di-Cl at 4,5, -NO2 groups at 2-position of phenyl ring B and hydroxy group at ortho-position of phenyl ring C, emerged as the most potent inhibitors of both targeted enzymes (AChE and BuChE) among the current series. A structure-activity relationship (SAR) was developed based on nature, position, number, electron donating/withdrawing effects of substitution/s on phenyl rings. Molecular docking studies were used to describe binding interactions of the most active inhibitors with active sites of AChE and BuChE.  相似文献   
83.
An ultrasonic-assisted leaching procedure was developed for the determination of heavy elements (As, Cu, Cd, Pb, and Zn) in Certified Reference Material of human hair (CRM 397) provided from the Community Bureau of Reference (BCR) of the Commission of the European Community. Concentrated nitric acid-30% hydrogen peroxide (2 + 1) was used for the leaching method. The effects of different factors on acid leaching of elements, such as presonication time (without ultrasonic stirring), sonication or exposure time to ultrasound, and temperature of the ultrasonic bath have been investigated. Optimum values of these parameters were selected for the maximum extraction of heavy metals from CRM BCR 397 and human scalp hair samples of normal healthy males. To check the validity of the proposed method, a wet acid digestion method was used to obtain the total elemental concentration in CRM BCR 397 and scalp hair samples. Cu and Zn in leachate and digests were measured by flame atomic absorption spectrometry using a conventional air/acetylene flame, while As, Cd, and Pd were determined by electrothermal atomic absorption spectrometry. Under optimized conditions, the recovery for Zn, Cd, Pd, As, and Cu was 98, 98.5, 97.5, 98.2, and 95%, respectively, of those obtained with the wet acid digestion method.  相似文献   
84.
Perovskoate, an isorinic acid derivative (1) and perovskoside, the catechol derivative (2) have been isolated from the ethyl acetate soluble fraction of the whole plant of Perovskia atriplicifolia and assigned the structure 3(7-hydroxyphenyl)-2-hydroxy propanoic acid; (R)-form, 2-O-(6',7'-dihydroxy-E-cinnamoyl) (1) and 2-methoxy-4-(undecyl-4'-O-beta-D-glucopyranosyl) phenol (2). In addition, caffeic acid (3) and ferulic acid (4) have been reported for the first time from this species. The structures of these compounds were assigned on the basis of 1D and 2D NMR techniques. The compound 1 showed significant inhibitory activity against lipoxygenase and weak to moderate activity against cholinesterases.  相似文献   
85.
The microbial transformation of levonorgestrel (1) by Cunningham elegans resulted in the formation of five hydroxylated metabolites, 13-ethyl-10beta, 17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one(2), 13-ethyl-6beta,17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (3) 13-ethyl 6beta, 10beta, 17beta-trihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (4) 13-ethyl-15alpha-17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (5) and 13-ethyl-11alpha, 17beta-dihydroxy-18,19-dinor-17alpha-pregn-4en-20-yn-3-one. The fermentation of one with Rhizopus stolonifer, Fusarium lini and Curvularia lunata afforded compound 2 as a major metabolise. These metabolites were structurally characterized on the basis of spectroScopic techniques. Metabolite 6 was identified as a new compound. Compounds 2 2 ad 5 displayed inhibitory activity against the acetylcholinesterase ( AChE, EC. 3.1.1.7) with IC50 values of 79.2 and 24.5 microM, respectively. The metabolites 2 and 5 also showed inhibitory activity against the butyryLcholinesterase ( BChE, E.C 3.1.1.8) with IC50 values ranging between 9.4 and 309.8 microM.  相似文献   
86.
In this letter, we present a facile route to produce metastable tetragonal zirconia (ZrO2) nanoparticles via pH-controlled precipitation of dilute zirconyl nitrate dihydrate [ZrO(NO3)2·2H2O] solution in liquid NH3 under ambient conditions and calcination at 500 °C for 2 h. The phase pure tetragonal ZrO2 nanoparticles are obtained at pH 9. The effect of pH on metastable phase stabilization in precipitated ZrO2 nanoparticles is demonstrated with the help of XRD, SEM/EDX, and X-ray photoelectron spectroscopy techniques. The stability of tetragonal ZrO2 phase is attributed to the smaller crystallite size and greater oxygen deficiency in phase-pure tetragonal ZrO2.  相似文献   
87.
We define nice partitions of the multicomplex associated with a Stanley ideal. As the main result we show that if the monomial ideal I is a CM Stanley ideal, then I p is a Stanley ideal as well, where I p is the polarization of I.  相似文献   
88.
Nanocontact properties of two-dimensional (2D) materials are closely dependent on their unique nanomechanical systems, such as the number of atomic layers and the supporting substrate. Here, we report a direct observation of toplayer-dependent crystallographic orientation imaging of 2D materials with the transverse shear microscopy (TSM). Three typical nanomechanical systems, MoS2 on the amorphous SiO2/Si, graphene on the amorphous SiO2/Si, and MoS2 on the crystallized Al2O3, have been investigated in detail. This experimental observation reveals that puckering behaviour mainly occurs on the top layer of 2D materials, which is attributed to its direct contact adhesion with the AFM tip. Furthermore, the result of crystallographic orientation imaging of MoS2/SiO2/Si and MoS2/Al2O3 indicated that the underlying crystalline substrates almost do not contribute to the puckering effect of 2D materials. Our work directly revealed the top layer dependent puckering properties of 2D material, and demonstrate the general applications of TSM in the bilayer 2D systems.  相似文献   
89.
90.
The CPV-2 DNA extracted from dog's intestine was amplified using RPA and transcribed into an RNA copy. The RNA copy was incubated with Cas13a and crRNA, upon activation collateral cleavage activity of Cas13a cleaves all the target RNA and nonspecific RNA in the vicinity producing fluorescent signals within 30 min.  相似文献   
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