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931.
《印度化学会志》2023,100(1):100823
The newly synthesized, characterized, and theoretically investigated Schiff base compound (E)-4-bromo-2-hydroxybenzylidene) amino)-N-(pyrimidin-2-yl) benzenesulfonamide (5BRSDA). Sulfadiazine and 5-bromosalicylaldehyde Schiff-base were the building blocks for the new compound. We were surprised by the variety in the structure of the results. By employing density functional theory (DFT), researchers were able to analyze the new compound molecular properties, geometric optimization, vibrational, frontier molecular orbitals, and energy evaluation. In addition, disc well diffusion was used to test the compounds antibacterial and antifungal properties. As compared to free ligands, the compound had a more potent pathogenic effect on the tested microbes, according to the findings. An in-depth molecular docking study on 1NTA provided new information about the inhibitory effects it has on pathogenic microbes. When compared to a literature survey, comparative analysis revealed that the titled compound had higher antibacterial and antifungal activity.  相似文献   
932.
Neuraminidase is an important target in the treatment of the influenza A virus. Screening natural neuraminidase inhibitors from medicinal plants is crucial for drug research. This study proposed a rapid strategy for identifying neuraminidase inhibitors from different crude extracts (Polygonum cuspidatum, Cortex Fraxini, and Herba Siegesbeckiae) using ultrafiltration combined with mass spectrometry guided by molecular docking. Firstly, the main component library of the three herbs was established, followed by molecular docking between the components and neuraminidase. Only the crude extracts with numbers of potential neuraminidase inhibitors identified by molecular docking were selected for ultrafiltration. This guided approach reduced experimental blindness and improved efficiency. The results of molecular docking indicated that the compounds in Polygonum cuspidatum demonstrated good binding affinity with neuraminidase. Subsequently, ultrafiltration-mass spectrometry was employed to screen for neuraminidase inhibitors in Polygonum cuspidatum. A total of five compounds were fished out, and they were identified as trans-polydatin, cis-polydatin, emodin-1-O-β-D-glucoside, emodin-8-O-β-D-glucoside, and emodin. The enzyme inhibitory assay showed that they all had neuraminidase inhibitory effects. In addition, the key residues of the interaction between neuraminidase and fished compounds were predicted. In all, this study could provide a strategy for the rapid screening of the potential enzyme inhibitors from medicinal herbs.  相似文献   
933.
Qishen Gubiao granules, a traditional Chinese medicine preparation composed of nine herbs, have been widely used to prevent and treat coronavirus disease 2019 with good clinical efficacy. In the present study, an integrated strategy based on chemical profiling followed by network pharmacology and molecular docking was employed, to explore the active components and potential molecular mechanisms of Qishen Gubiao granules in the therapy of coronavirus disease 2019. Using the ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry technique, a total of 186 ingredients corresponding to eight structure types in Qishen Gubiao preparation were identified or structurally annotated with the elucidation of the fragmentation pathways in the typical compounds. The network pharmacology analysis screened 28 key compounds including quercetin, apigenin, scutellarein, luteolin and naringenin acting on 31 key targets, which possibly modulated signal pathways associated with immune and inflammatory responses in the treatment of coronavirus disease 2019. The molecular docking results observed that the top 5 core compounds had a high affinity for angiotensin-converting enzyme 2 and 3-chymotrypsin-like protease. This study proposed a reliable and feasible approach for elucidating the multi-components, multi-targets, and multi-pathways intervention mechanism of Qishen Gubiao granules against coronavirus disease 2019, providing a scientific basis for its further quality evaluation and clinical application.  相似文献   
934.
Platycodi Radix (PR) is a valuable herb that is widely used in the treatment of chronic obstructive pulmonary disease in clinics. However, the mechanism of action for the treatment of chronic obstructive pulmonary disease remains unclear due to the lack of in vivo studies. Our study established a novel integrated strategy based on ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry, network pharmacology, and molecular docking to systematically analyze the tissue distribution and active compounds of PR in vivo and the therapeutic mechanism of chronic obstructive pulmonary disease. First, tissue distribution studies have shown that the lung is the organ with the highest distribution of PR compounds. Subsequently, network pharmacology results showed that the tumor necrosis factor signaling pathway, interleukin-17 signaling pathway, and mitogen-activated protein kinase signaling pathway were the critical mechanisms of PR against chronic obstructive pulmonary disease. Ultimately, molecular docking results showed that the key targets were stably bound to the corresponding active compounds of PR. Our study is of great significance for the screening of the key effective compounds and the study of the mechanism of action in traditional Chinese medicine and provides data to support the further development and utilization of PR.  相似文献   
935.
936.
Ficus palmata Forssk. (Moraceae family) is medicinally valuable plant that is mostly used as folk medicine for the treatment of different diseases. Phytochemical composition was evaluated by preliminary phytochemical investigation, GCMS analysis, and total bioactive contents (TPC and TFC). The antioxidant, enzyme inhibition, antimicrobial, thrombolytic and anticancer activities were performed for biological evaluation. The extract exhibited the maximum total phenolic (49.24 ± 1.21 mg GAE/g) and total flavonoid contents (29.9 ± 1.13 mg QE/g) which may be correlated to higher antioxidant potential of extract. The GCMS investigation identified the presence of 27 phytocompounds of different classes related to aldehydes, esters of fatty acids, triterpenes, steroids, triterpenoid. The extract possessed the strong α-glucosidase (73.4 ± 4.65 %) and moderate α-amylase inhibition activity (47.1 ± 3.29 %). Significant results were observed in case of antiviral, antifungal, and antibacterial activities. F. palmata extract inhibited the growth of HepG2 cancer cells in a dose-dependent manner. The extract also exhibited moderate in vitro thrombolytic activity. In addition, the phytocompounds identified by GCMS were subjected to in silico molecular docking studies to analyze the binding affinity between phytocompounds and enzymes (α-glucosidase and α-amylase). Moreover, the best docked compounds were selected for ADMET studies which provide information about pharmacokinetics, physicochemical properties, drug-likeness, and toxicity of identified phytocompounds. The outcome of our research revealed that ethanolic extract of F. palmata possessed good antidiabetic, antimicrobial, thrombolytic and anticancer potential. This plant should be further explored to isolate the bioactive compounds for new drug development.  相似文献   
937.
《印度化学会志》2023,100(2):100869
Because bioactive ester derivatives are important pharmacophores, the current study focuses on the synthesis and evaluation of their pharmacological activity. In this case, novel 1,3-diethyl 2-(4-[3-ethoxy-2-(ethoxycarbonyl)-3-oxo-2-phenylpropyl]-2,5-dimethylphenylmethyl)-2-phenylpropanedioate (C36H42O8) was synthesized in good yield. Elemental analysis, mass spectroscopy, FT-IR and NMR spectroscopy are used to analyse the compound. The X-ray diffraction examination of a single crystal indicates that the molecular structure crystallises in the monoclinic space group P21/n, with half of the molecule being crystallographically unique (Z' = 0.5) with Z = 2. Surprisingly, the inversion centre is located at the centre of the methyl-substituted benzene ring, which generates the entire molecule via symmetry operation. Crystallographic and computational chemistry technologies are used to examine the nature and strength of intermolecular interactions amongst inversion-related dimers (Hirshfeld surface, energy framework, QTAIM and NCI analysis). Koopman's approximation was used to calculate the frontier molecular orbitals, HOMO-LUMO energy gap, and associated reactive parameters. Furthermore, molecular docking experiments demonstrated the compound with Antieczematic proteins as well as protein-ligand interactions, hydrogen bond interactions are delibrated.  相似文献   
938.
《印度化学会志》2023,100(1):100835
The (Z)-N-(pyrimidin-2-yl)-4-(thiophen-2-ylmethylene)amino) benzenesulfonamide (TH2DA) were synthesized and characterized by the Infrared, UV–Visible, and NMR analysis. Using density functional theory, the current work is a set of theoretical studies on TH2DA. The compound molecular structure and geometry were defined using DFT. Topological studies, like ELF, LOL, ALIE, and RDG studies, were done with the Multiwfn-3.8 to find the main binding areas and weak interactions in the molecule. Using the IEFPCM solvation model were used to study the calculated UV–Visible spectrum. The HOMO-LUMO, MEP, and NLO properties were carried out in the gas phase. The NBO calculations are used to study how charges move between and within the molecule and stability of this molecule. A pharmacological analysis is done using online tool like Swiss-ADME, to see if the molecule could be potential drug candidate; this evaluation looks at the drug-likeness, ADME and eco-friendly toxicity properties of the TH2DA molecule. Auto-dock suite and Discovery studio Visualizer are used to do molecular docking studies.  相似文献   
939.
《印度化学会志》2023,100(2):100910
Spectroscopic methods (NMR, UV–vis) were utilized to get an understanding of the molecular structure of the (E)-4-((4-chlorobenzylidene)amino)-N-(thiazole-2yl) benzenesulfonamide (4CLBTH). The DFT/B3LYP/cc-pVDZ, were used in the theoretical study of the compound. Calculations using DFT can produce geometrical parameters such as bond lengths and bond angles. The GIAO method was utilized in DMSO to calculate the 1H and 13C NMR for TMS. These results were then compared to the observed data. The UV–Vis spectrum of 4CLBTH was computed by using the B3LYP with the cc-pVDZ basis set. Using theoretical calculations, an investigation into the FMO analysis and the MEP were carried out. The theoretical findings and the experimental findings are in reasonable agreement with one another. The molecular docking was investigated by the autodock suite and visualised using the discovery studio visualizer. The multiwfn software was used to calculate the wavefunction studies.  相似文献   
940.
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