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761.
徐旭平 《文山师范高等专科学校学报》2002,14(1):5-9
对曹雪芹文学思想的研究,目前学术界还是一片空白,本文从《红楼梦》原著去探讨曹雪芹的文学思想,认为作品体现了作者四个方面的文学思想,一是对“诗言志”传统的继承和发扬,二是对比兴寄托手法的运用和拓展,三是对虚实相生,有无相成艺术创作原则的把握,四是对“意境”的营建,对它们进行认真的总结和仔细的研究,和对作品本身的研究一样,同样具有十分重要的意义。 相似文献
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This paper presents an experimental validation of the use of the virtual fields method to identify the elasto-plastic behaviour
of an iron specimen from full-field measurements with the grid method and a simple heterogeneous test configuration. The experimental
procedure is carefully detailed since it is of primary importance to obtain good identification results. In particular, the
use of two back-to-back cameras has proved essential to eliminate out-of-plane effects. Then, the procedure for extracting
the elastic parameters and the parameters of a Voce’s hardening model using the virtual fields method is presented. The results
are very convincing and encouraging for future developments using more complex test geometries leading to fully multi-axial
stress states. It is a first step towards the development of such inverse procedures as an alternative to difficult and costly
methods involving homogeneous tests using multi-axial testing machines. 相似文献
763.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the COVID-19 which has infected millions of people worldwide. The main protease of SARS-CoV-2 (MPro) has been recognized as a key target for the development of antiviral compounds. Taking advantage of the X-ray crystal complex with reversible covalent inhibitors interacting with the catalytic cysteine 145 (Cys145), we explored flexible docking studies to select alternative compounds able to target this residue as covalent inhibitors. First, docking studies of three known electrophilic compounds led to results consistent with co-crystallized data validating the method for SARS-CoV-2 MPro covalent inhibition. Then, libraries of soft electrophiles (overall 41 757 compounds) were submitted to docking-based virtual screening resulting in the identification of 17 molecules having their electrophilic group close to the Cys145 residue. We also investigated flexible docking studies of a focused approved covalent drugs library including 32 compounds with various electrophilic functional groups. Among them, the calculations resulted in the identification of four compounds, namely dimethylfumarate, fosfomycin, ibrutinib and saxagliptin, able first, to bind to the active site of the protein and second, to form a covalent bond with the catalytic cysteine. 相似文献
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Multidrug resistance (MDR) is one of the serious problems in cancer research that causes failure in chemotherapy. Chromene-based compounds have been proven to be the novel anti-MDR agents for inhibiting proliferation of tumor cells through tubulin polymerization inhibition of by binding at the colchicine binding site. In this study, we screened a chromene-based database of small molecules using physicochemical, ADMET properties and molecular docking to identify potential hit compounds. In order to validate our hit compounds, molecular dynamics simulations and related analysis were carried out and the results suggest that our hit compounds (PubChem CIDs: 16814409, 17594471, 57367244 and 69899719) can prove to be potential inhibitors of tubulin. The in silico results show that the present hits, like colchicine, effectively suppressed the dynamic instability of microtubules and induced microtubule-depolymerization and cell cycle arrest. 相似文献
765.
Heat shock protein 70 is an effective anticancer target as it influences many signaling pathways. Hence the study investigated the important pharmacophore feature required for ATPase inhibitors of HSP70 by generating a ligand based pharmacophore model followed by virtual based screening and subsequent validation by molecular docking in Discovery studio V4.0. The most extrapolative pharmacophore model (hypotheses 8) consisted of four hydrogen bond acceptors. Further validation by external test set prediction identified 200 hits from Mini Maybridge, Drug Diverse, SCPDB compounds and Phytochemicals. Consequently, the screened compounds were refined by rule of five, ADMET and molecular docking to retain the best competitive hits. Finally Phytochemical compounds Muricatetrocin B, Diacetylphiladelphicalactone C, Eleutheroside B and 5-(3-{[1-(benzylsulfonyl)piperidin-4-yl]amino}phenyl)- 4-bromo-3-(carboxymethoxy)thiophene-2-carboxylic acid were obtained as leads to inhibit the ATPase activity of HSP70 in our findings and thus can be proposed for further in vitro and in vivo evaluation. 相似文献
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何成战 《广西民族大学学报》2013,19(2):63-66
采用3DSMax8.0软件,配合Vrp7.0制作虚拟现实平台,设计一套基于计算机虚拟现实技术的古建筑虚拟复原系统实现方案,完成对广西三江县程阳风雨桥数字重建过程,给出风雨桥的数字重建流程与具体的计算机虚拟重建的步骤,为文化遗产的数字化复原和保护提供可靠的技术支撑. 相似文献