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491.
Francesco Musiani Laura Rigobello Luisa Iommarini Valerio Carelli Mauro Degli Esposti Anna Maria Ghelli 《Molecules (Basel, Switzerland)》2022,27(4)
The finding that the most common mitochondrial DNA mutation m.11778G>A/MT-ND4 (p.R340H) associated with Leber’s hereditary optic neuropathy (LHON) induces rotenone resistance has produced a long-standing debate, because it contrasts structural evidence showing that the ND4 subunit is far away from the quinone-reaction site in complex I, where rotenone acts. However, recent cryo-electron microscopy data revealed that rotenone also binds to the ND4 subunit. We investigated the possible structural modifications induced by the LHON mutation and found that its amino acid replacement would disrupt a possible hydrogen bond between native R340 and Q139 in ND4, thereby destabilizing rotenone binding. Our analysis thus explains rotenone resistance in LHON patients as a biochemical signature of its pathogenic effect on complex I. 相似文献
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Valerio Magnasco Arnaldo Rapallo Massimo Casanova 《International journal of quantum chemistry》1999,73(4):333-340
A new translation method for Slater‐type orbitals (STOs) is proposed involving exact translation of the regular solid harmonic part of the orbital followed by the series expansion of the residual spherical part in powers of the radial variable. The method is positively tested in the case of the overlap integral, showing good rate of convergence and great numerical stability under wide changes in the relevant molecular parameters. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 73: 333–340, 1999 相似文献
494.
Ivana Barravecchia Elisabetta Barresi Camilla Russo Francesca Scebba Chiara De Cesari Valerio Mignucci Davide De Luca Silvia Salerno Valeria La Pietra Mariateresa Giustiniano Sveva Pelliccia Diego Brancaccio Greta Donati Federico Da Settimo Sabrina Taliani Debora Angeloni Luciana Marinelli 《Molecules (Basel, Switzerland)》2021,26(24)
Molecule interacting with CasL 2 (MICAL2), a cytoskeleton dynamics regulator, are strongly expressed in several human cancer types, especially at the invasive front, in metastasizing cancer cells and in the neo-angiogenic vasculature. Although a plethora of data exist and stress a growing relevance of MICAL2 to human cancer, it is worth noting that only one small-molecule inhibitor, named CCG-1423 (1), is known to date. Herein, with the aim to develop novel MICAL2 inhibitors, starting from CCG-1423 (1), a small library of new compounds was synthetized and biologically evaluated on human dermal microvascular endothelial cells (HMEC-1) and on renal cell adenocarcinoma (786-O) cells. Among the novel compounds, 10 and 7 gave interesting results in terms of reduction in cell proliferation and/or motility, whereas no effects were observed in MICAL2-knocked down cells. Aside from the interesting biological activities, this work provides the first structure–activity relationships (SARs) of CCG-1423 (1), thus providing precious information for the discovery of new MICAL2 inhibitors. 相似文献
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Ruel Valerio Robles De Grano Elena V. Vashchenko Madiha Nisar Herman H.-Y. Sung Valerii V. Vashchenko Ian D. Williams 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(5):490-499
The flavonoid Oroxylin A (6‐methoxychrysin or 5,7‐dihydroxy‐6‐methoxy‐2‐phenyl‐4H‐chromen‐4‐one, C16H12O5) and its regioisomers are of increasing interest for a variety of bioactive functions and their pharmaceutical formulation is of importance. Previous difficulties in the separation and misidentification of Oroxylin A from its regioisomers Wogonin (8‐methoxychrysin or 5,7‐dihydroxy‐8‐methoxy‐2‐phenyl‐4H‐chromen‐4‐one) and Negletein (5,6‐dihydroxy‐7‐methoxyflavone or 5,6‐dihydroxy‐7‐methoxy‐2‐phenyl‐4H‐chromen‐4‐one) render its full structural and powder X‐ray characterization highly desirable. The low‐temperature (100 K) crystal structures of Oroxylin A, Negletein and Wogonin sesquihydrate are reported for the first time. Wogonin crystallizes in two related but distinct hydrated forms. These have very similar powder diffractograms, indicating that such issues need to be addressed for its pharmaceutical formulation. 相似文献
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Antoni Planes Pol Lloveras Teresa Castán Avadh Saxena Marcel Porta 《Continuum Mechanics and Thermodynamics》2012,24(4-6):619-627
A Ginzburg–Landau free-energy model is proposed to study spatially inhomogeneous states that often occur as precursors of ferroelastic/martensitic transitions. Disorder is included in the harmonic coefficient of the free-energy density which gives rise to a spatial distribution of transition temperatures, and lattice integrity is imposed through Saint-Vénant compatibility conditions which lead to a long-range anisotropic elastic interaction. We show that precursor textures are a result of the competition between elastic anisotropy and disorder. Cross-hatched modulations (tweed patterns) take place for temperatures above the martensitic phase in the limit of high anisotropy and/or low disorder while a nano-cluster phase-separated state occurs at low anisotropies or high disorder. In the latter case, nanoscale inhomogeneities give rise to glassy behaviour while the structural transition is inhibited. Interestingly, in this case, the ferroelastic system also displays a large thermo-mechanical response so that the low-symmetry structure can be easily induced by the application of relatively small stresses within a broad temperature range. 相似文献