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排序方式: 共有1422条查询结果,搜索用时 15 毫秒
61.
62.
Dr. Jérémie Topin Claire A. de March Dr. Landry Charlier Prof. Dr. Catherine Ronin Prof. Dr. Serge Antonczak Dr. Jérôme Golebiowski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10227-10230
A joint approach combining free‐energy calculations and calcium‐imaging assays on the broadly tuned human 1G1 olfactory receptor is reported. The free energy of binding of ten odorants was computed by means of molecular‐dynamics simulations. This state function allows separating the experimentally determined eight agonists from the two non‐agonists. This study constitutes a proof‐of‐principle for the computational deorphanization of olfactory receptors. 相似文献
63.
Henry W. Orton Dr. Jan Stanek Dr. Tobias Schubeis Dylan Foucaudeau Claire Ollier Dr. Adrian W. Draney Dr. Tanguy Le Marchand Dr. Diane Cala-De Paepe Prof. Dr. Isabella C. Felli Prof. Dr. Roberta Pierattelli Prof. Dr. Sebastian Hiller Dr. Wolfgang Bermel Dr. Guido Pintacuda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2400-2405
64.
Angus Campbell Dr. Ian Mat Som Dr. Claire Wilson Prof. Dr. J. Stephen Clark 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1155-1160
Six members of the asbestinin family of marine diterpene natural products have been synthesized in an efficient and stereoselective manner from a single oxa-bridged intermediate. Five of these natural products have not been synthesized previously and the structures of four of them have been confirmed as those proposed originally or following revisions to the original structures. The fifth natural product—asbestinin-21—has been shown to be a diastereomer of the compound that had been proposed previously. 相似文献
65.
Jinny Claire Lee Hye Yun Kim Sejin Lee Jisu Shin Hyunjin Vincent Kim Kyeonghwan Kim Seungyeop Baek Donghee Lee Hanna Jeon DaWon Kim Seung‐Hoon Yang Gyoonhee Han Keunwan Park Jaeho Choi Jinwoo Park Jason A. Moss Kim D. Janda YoungSoo Kim 《Angewandte Chemie (International ed. in English)》2020,59(28):11491-11500
Amyloid‐β (Aβ) oligomers are implicated in Alzheimer disease (AD). However, their unstable nature and heterogeneous state disrupts elucidation of their explicit role in AD progression, impeding the development of tools targeting soluble Aβ oligomers. Herein parallel and anti‐parallel variants of Aβ(1–40) dimers were designed and synthesized, and their pathogenic properties in AD models characterized. Anti‐parallel dimers induced cognitive impairments with increased amyloidogenesis and cytotoxicity, and this dimer was then used in a screening platform. Through screening, two FDA‐approved drugs, Oxytetracycline and Sunitinib, were identified to dissociate Aβ oligomers and plaques to monomers in 5XFAD transgenic mice. In addition, fluorescent Astrophloxine was shown to detect aggregated Aβ in brain tissue and cerebrospinal fluid samples of AD mice. This screening platform provides a stable and homogeneous environment for observing Aβ interactions with dimer‐specific molecules. 相似文献
66.
Hossein Vahabi Laurent Ferry Claire Longuet Rodolphe Sonnier Claire Negrell-Guirao Ghislain David José-Marie Lopez-Cuesta 《European Polymer Journal》2012,48(3):604-612
The influence of phosphonated groups on thermal degradation and flammability has been investigated in the case of two chemically modified PMMA. Thermogravimetric analysis as well as pyrolysis combustion flow calorimetry have been used to define the efficiency of phosphorus in both condensed and vapor phases. A theoretical study was also performed to determine the contribution of phosphonated groups to the effective heat of combustion, residue content and heat release capacity. Empirical and theoretical approaches agreed to highlight that PMMA modified with monophosphonated comonomer is more efficient in both condensed and vapor phases in terms of flammability and char formation. These results were attributed to the ability of phosphonate groups to interact with ester groups and also to the weakness of the P–C–N bonds. Moreover, this study proposes a method for designing the chemical environment of phosphonate group in polymers to achieve better flame retardancy. 相似文献
67.
Fave C Hissler M Sénéchal K Ledoux I Zyss J Réau R 《Chemical communications (Cambridge, England)》2002,(16):1674-1675
In plane parallel arrangement and enhancement of NLO-activity are observed upon coordination of heteroditopic dipoles containing a phosphole ring on square-planar d8-palladium centre. 相似文献
68.
Double-quantum filtered MAS NMR spectra of an isolated homonuclear spin-1/2 pair are considered, at and away from rotational resonance conditions. The pulse sequence used is the solid-state NMR equivalent of double-quantum filtered COSY, known from solution-state NMR. The 119Sn spin pair in [(chex3Sn)2S] is characterized by a difference in isotropic chemical shielding smaller than the two chemical shielding anisotropies and by direct dipolar and isotropic J-coupling constants of similar magnitudes. At rotational resonance, one-dimensional double-quantum filtered 119Sn lineshapes yield the relative orientation of the two 119Sn chemical shielding tensors. Good double-quantum filtration efficiencies are found at and away from rotational resonance conditions, despite the presence of large chemical shielding anisotropies. Numerical simulations illustrate the interplay of the direct dipolar and J-coupling pathways and identify the latter as the main pathway even at rotational resonance conditions. 相似文献
69.
Background
It is well established that nucleus basalis magnocellularis (NbM) lesions impair performance on tests of sustained attention. Previous work from this laboratory has also demonstrated that pedunculopontine tegmental nucleus (PPTg) lesioned rats make more omissions on a test of sustained attention, suggesting that it might also play a role in mediating this function. However, the results of the PPTg study were open to alternative interpretation. We aimed to resolve this by conducting a detailed analysis of the effects of damage to each brain region in the same sustained attention task used in our previous work. Rats were trained in the task before surgery and post-surgical testing examined performance in response to unpredictable light signals of 1500 ms and 4000 ms duration. Data for PPTg lesioned rats were compared to control rats, and rats with 192 IgG saporin infusions centred on the NbM. In addition to operant data, video data of rats' performance during the task were also analysed. 相似文献70.
James B. Gerken Claire Badger Christopher Bisbee Sasha Gardner Yan Qi Víctor Durà Vilà John D. Roberts 《Journal of Physical Organic Chemistry》2008,21(3):193-197
Conformational preferences of glutaric, 3‐hydroxyglutaric and 3‐methylglutaric acid, and their mono‐ and dianions have been investigated with the aid of NMR spectroscopy. In contrast to succinic acid, glutaric acid displays essentially statistical conformational equilibria in polar and non‐polar solutions of high and low hydrogen‐bonding ability with no clear evidence for intramolecular hydrogen‐bonding interactions. The acid ionization constant ratios, K 1/K2, in D2O and DMSO of glutaric, 3‐hydroxyglutaric, and 3‐methylglutaric acids also indicate that intramolecular interactions are much less important than, or indeed insignificant, for shorter‐chain acids. FTIR studies on 3‐methylglutaric acid indicate some preference for either association with solvent or dimerization, depending on the solvent, rather than intramolecular hydrogen bonding. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献