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41.
Viet Hung Dao Isabelle Ourliac-Garnier Cdric Log Florence O. McCarthy Stphane Bach Teresinha Gonalves da Silva Caroline Denevault-Sabourin Jrme Thifaine Blandine Baratte Thomas Robert Fabrice Gouilleux Marie Brachet-Botineau Marc-Antoine Bazin Pascal Marchand 《Molecules (Basel, Switzerland)》2021,26(21)
Pim kinases (proviral integration site for Moloney murine leukemia virus kinases) are overexpressed in various types of hematological malignancies and solid carcinomas, and promote cell proliferation and survival. Thus, Pim kinases are validated as targets for antitumor therapy. In this context, our combined efforts in natural product-inspired library generation and screening furnished very promising dibenzo[b,d]furan derivatives derived from cercosporamide. Among them, lead compound 44 was highlighted as a potent Pim-1/2 kinases inhibitor with an additional nanomolar IC50 value against CLK1 (cdc2-like kinases 1) and displayed a low micromolar anticancer potency towards the MV4-11 (AML) cell line, expressing high endogenous levels of Pim-1/2 kinases. The design, synthesis, structure–activity relationship, and docking studies are reported herein and supported by enzyme, cellular assays, and Galleria mellonella larvae testing for acute toxicity. 相似文献
42.
Jill K. Wolken Viet Q. Nguyen František Tureček 《Journal of mass spectrometry : JMS》1997,32(11):1162-1169
Hypervalent organic ammonium radicals were generated by collisional neutralization with dimethyl disulfide of protonated 1,4-diazabicyclo[2.2.2]octane (1H+), N,N′-dimethylpiperazine (2H+) and N-methylpiperazine (3H+). The radicals dissociated completely on the 5.1 μs time-scale. Radical 1H• underwent competitive N−H and N−C bond dissociations producing 1,4-diazabicyclo[2.2.2]octane and small ring fragments. Dissociations of radical 2H• proceeded by N−H bond dissociation and ring cleavage, whereas N−CH3 bond cleavage was less frequent. Radical 3H• underwent N−H, N−CH3 and N−Cring bond cleavages followed by post-reionization dissociations of the formed cations. The pattern of bond dissociations in the hypervalent ammonium radicals derived from six-membered nitrogen heterocycles is similar to those of aliphatic ammonium radicals. © 1997 John Wiley & Sons, Ltd. 相似文献
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44.
Celastrus hindsii is a popular medicinal plant in Vietnam and Southeast Asian countries as well as in South America. In this study, an amount of 12.05 g of an α-amyrin and β-amyrin mixture was isolated from C. hindsii (10.75 g/kg dry weight) by column chromatography applying different solvent systems to obtain maximum efficiency. α-Amyrin and β-amyrin were then confirmed by gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR). The antioxidant activities of the α-amyrin and β-amyrin mixture were determined via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,20-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays with IC50 of 125.55 and 155.28 µg/mL, respectively. The mixture exhibited a high potential for preventing gout by inhibiting a relevant key enzyme, xanthine oxidase (XO) (IC50 = 258.22 µg/mL). Additionally, an important enzyme in skin hyperpigmentation, tyrosinase, was suppressed by the α-amyrin and β-amyrin mixture (IC50 = 178.85 µg/mL). This study showed that C. hindsii is an abundant source for the isolation of α-amyrin and β-amyrin. Furthermore, this was the first study indicating that α-amyrin and β-amyrin mixture are promising in future therapies for gout and skin hyperpigmentation. 相似文献
45.
Duong Quoc Viet 《Journal of Pure and Applied Algebra》2009,213(11):2104-2116
Let A be a Noetherian local ring with the maximal ideal m and an m-primary ideal J. Let S=?n≥0Sn be a finitely generated standard graded algebra over A. Set S+=?n>0Sn. Denote by FJ(S)=?n≥0→(Sn/JSn) the fiber cone of S with respect to J. The paper characterizes the multiplicity and the Cohen-Macaulayness of FJ(S) in terms of minimal reductions of S+. 相似文献
46.
Ha Thi-Thanh Vu Hanh Thi-Minh Pham Tuyen Viet Nguyen Hieu Khac Ho 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(4):65
In this paper, the moment method in statistical mechanics has been employed to study the pressure effects on thermodynamic and mechanical properties of zinc-blende zinc telluride using many-body potential. We have derived the analytical expressions of the pressure-dependent lattice parameter, volume compression as well as mean-square displacement of zinc-blende type compound. Numerical calculations performed for ZnTe compound up to 12 GPa are found to be in good and reasonable agreement with available experimental data as well as with previous theoretical studies. These results have been used to evaluate the bulk modulus and its first pressure derivative of ZnTe. The present moment method has taken into account the quantum zero-point vibrations at low temperature and the higher-order anharmonic terms in the atomic displacements. This research shows the advantage of moment method on extensively studying thermo-mechanical properties of materials under high pressures. 相似文献
47.
48.
Effects of amyloid beta (Aβ) peptide Aβ(40) on secondary structures of Aβ(42) are studied by all-atom simulations using the GROMOS96 43a1 force field with explicit water. It is shown that in the presence of Aβ(40) the beta-content of monomer Aβ(42) is reduced. Since the fibril-prone conformation N? of full-length Aβ peptides has the shape of beta strand-loop-beta strand this result suggests that Aβ(40) decreases the probability of observing N? of Aβ(42) in monomer state. Based on this and the hypothesis that the higher is the population of N? the higher fibril formation rates, one can expect that, in agreement with the recent experiment, Aβ(40) inhibit fibril formation of Aβ(42). It is shown that the presence of Aβ(40) makes the salt bridge D23-K28 and fragment 18-33 of Aβ(42) more flexible providing additional support for this experimental fact. Our estimation of the binding free energy by the molecular mechanics-Poisson-Boltzmann surface area method reveals the inhibition mechanism that Aβ(40) binds to Aβ(42) modifying its morphology. 相似文献
49.
Christian Decker Danielle Decker Trieu Nguyen Thi Viet Hien Le Xuan 《Macromolecular Symposia》1996,102(1):63-71
Different types of tridimensional polymer networks have been synthetised by photoinitiated cationic polymerisation of vinyl ether and epoxy-functionalised oligomers and polymers. The polymerisation kinetics was followed by real-time infrared (RTIR) spectroscopy, a technique that records directly conversion versus time profiles in a timescale as short as 1 s. The addition of a diacrylate monomer was shown to accelerate the ring-opening polymerisation of epoxidized polyisoprene, with formation of interpenetrating polymer networks having well contrasted properties. A dual polymer network has been generated by photocrosslinking of a polyisoprene functionalised with both epoxy and acrylate groups. 相似文献
50.
Vu T. Nguyen Graham C. Haug Viet D. Nguyen Ngan T. H. Vuong Hadi D. Arman Oleg V. Larionov 《Chemical science》2021,12(18):6429
Sulfonamides feature prominently in organic synthesis, materials science and medicinal chemistry, where they play important roles as bioisosteric replacements of carboxylic acids and other carbonyls. Yet, a general synthetic platform for the direct conversion of carboxylic acids to a range of functionalized sulfonamides has remained elusive. Herein, we present a visible light-induced, dual catalytic platform that for the first time allows for a one-step access to sulfonamides and sulfonyl azides directly from carboxylic acids. The broad scope of the direct decarboxylative amidosulfonation (DDAS) platform is enabled by the efficient direct conversion of carboxylic acids to sulfinic acids that is catalyzed by acridine photocatalysts and interfaced with copper-catalyzed sulfur–nitrogen bond-forming cross-couplings with both electrophilic and nucleophilic reagents.Sulfonamides are now accessible directly from carboxylic acids by a one-step, tricomponent decarboxylative amidosulfonation that provides the missing link between the two key functionalities. 相似文献