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131.
132.
Kieran F. Scott Timothy J. Mann Shadma Fatima Mila Sajinovic Anshuli Razdan Ryung Rae Kim Adam Cooper Aflah Roohullah Katherine J. Bryant Kasuni K. Gamage David G. Harman Fatemeh Vafaee Garry G. Graham W. Bret Church Pamela J. Russell Qihan Dong Paul de Souza 《Molecules (Basel, Switzerland)》2021,26(23)
Phospholipase A2 (PLA2) enzymes were first recognized as an enzyme activity class in 1961. The secreted (sPLA2) enzymes were the first of the five major classes of human PLA2s to be identified and now number nine catalytically-active structurally homologous proteins. The best-studied of these, group IIA sPLA2, has a clear role in the physiological response to infection and minor injury and acts as an amplifier of pathological inflammation. The enzyme has been a target for anti-inflammatory drug development in multiple disorders where chronic inflammation is a driver of pathology since its cloning in 1989. Despite intensive effort, no clinically approved medicines targeting the enzyme activity have yet been developed. This review catalogues the major discoveries in the human group IIA sPLA2 field, focusing on features of enzyme function that may explain this lack of success and discusses future research that may assist in realizing the potential benefit of targeting this enzyme. Functionally-selective inhibitors together with isoform-selective inhibitors are necessary to limit the apparent toxicity of previous drugs. There is also a need to define the relevance of the catalytic function of hGIIA to human inflammatory pathology relative to its recently-discovered catalysis-independent function. 相似文献
133.
Chiara Dal Bosco Flavia Bonoli Alessandra Gentili Chiara Fanali Giovanni D&#x;Orazio 《Molecules (Basel, Switzerland)》2021,26(23)
A novel chromatographic application in chiral separation by using the nano-LC technique is here reported. The chiral recognition of 12 antifungal drugs was obtained through a 75 µm I.D. fused-silica capillary, which was packed with a CSP-cellulose 3,5-dichlorophenylcarbamate (CDCPC), by means of a lab-made slurry packing procedure. The mobile phase composition and the experimental conditions were optimized in order to find the optimum chiral separation for some selected racemic mixtures of imidazole and triazole derivatives. Some important parameters, such as retention faction, enantioresolution, peak efficiency, and peak shape, were investigated as a function of the mobile phase (pH, water content, type and concentration of both the buffer and the organic modifier, and solvent dilution composition). Within one run lasting 25 min, at a flow rate of approximately 400 nL min−1, eight couples of enantiomers were baseline-resolved and four of them were separated in less than 25 min. The method was then applied to milk samples, which were pretreated using a classical dispersive liquid–liquid microextraction technique preceded by protein precipitation. Finally, the DLLME-nano-LC–UV method was validated in a matrix following the main FDA guidelines for bioanalytical methods. 相似文献
134.
Ali Maghsoumi Uliana Beser Xinliang Feng Akimitsu Narita Klaus Müllen Chiara Castiglioni Matteo Tommasini 《Journal of Raman spectroscopy : JRS》2021,52(12):2301-2316
We report a detailed investigation by Raman spectroscopy of the holey nanographene C216 , a hexagon-shaped disk with armchair edges (1.4 nm long), from which the central aromatic ring is missing. Density functional theory (DFT) calculations allow to assign the main features of the Raman spectra that have been recorded with several excitation wavelengths. In the Raman spectra, we observe signatures of the hole in the structure, several G and D modes, as well as their overtones and combinations—up to third order. 相似文献
135.
Prof. Gianlorenzo Bussetti Claudia Filoni Prof. Andrea Li Bassi Dr. Alberto Bossi Prof. Marcello Campione Prof. Alessio Orbelli Biroli Prof. Chiara Castiglioni Dr. Silvia Trabattoni Dr. Stefania De Rosa Prof. Luca Tortora Prof. Franco Ciccacci Prof. Lamberto Duò 《ChemistryOpen》2021,10(8):748-755
We have recently discussed how organic nanocrystal dissolution appears in different morphologies and the role of the solution pH in the crystal detriment process. We also highlighted the role of the local molecular chemistry in porphyrin nanocrystals having comparable structures: in water-based acid solutions, protonation of free-base porphyrin molecules is the driving force for crystal dissolution, whereas metal (ZnII) porphyrin nanocrystals remain unperturbed. However, all porphyrin types, having an electron rich π-structure, can be electrochemically oxidized. In this scenario, a key question is: does electrochemistry represent a viable strategy to drive the dissolution of both free-base and metal porphyrin nanocrystals? In this work, by exploiting electrochemical atomic force microscopy (EC-AFM), we monitor in situ and in real time the dissolution of both free-base and metal porphyrin nanocrystals, as soon as molecules reach the oxidation potential, showing different regimes according to the applied EC potential. 相似文献
136.
Luca Banfi Andrea Basso Chiara Lambruschini Lisa Moni Renata Riva 《Chemical science》2021,12(47):15445
This perspective aims at celebrating the 100th anniversary of the discovery of the Passerini three component reaction. After being nearly neglected for many years, now this reaction has become quite popular, thanks to the achievements of the last 30 years, which have revealed several chances of exploitation in organic synthesis. Though not being comprehensive, this review means to show the various ways that have been used in order to expand the utility of the Passerini reaction. Post-MCR transformations to give heterocycles or peptidomimetics, variants through single component replacement, stereochemical issues, and applications in total syntheses will be especially covered.This perspective aims at celebrating the 100th anniversary of the discovery of the Passerini three component reaction. 相似文献
137.
Jiacheng Lin Chiara Figazzolo Michael A. Metrick II Pietro Sormanni Michele Vendruscolo 《Chemical science》2021,12(41):13940
The expansion of structural databases and the increase in computing power are enabling approaches for antibody discovery based on computational design. It has already been shown that it is possible to use this approach to generate antibodies for specific epitopes on challenging targets. Here we describe an application of this procedure for antibody maturation through the computational design of mutational variants of increased potency. We illustrate this procedure in the case of a single-domain antibody targeting an epitope in the N-terminal region of Aβ42, a peptide whose aggregation is closely associated with Alzheimer''s disease. We show that this approach enables the generation of an antibody variant with over 200-fold increased potency against the primary nucleation process in Aβ42 aggregation. Our results thus demonstrate that potentiated antibody variants can be obtained by computational maturation.A computational maturation method enables the generation of an antibody variant with over 200-fold increased potency against the primary nucleation process in Aβ42 aggregation. 相似文献
138.
139.
We used the recombinant phage display antibody system (RPAS) to obtain chimeric single-chain fragment variable (ScFv) antibodies
to gill proteins of the white clam Codakia orbicularis (Linné, 1758). After three rounds of selection on immunotubes loaded with total gill protein extract, recombinant phages
exhibiting antibodies to gill proteins were isolated and tested by enzyme-linked immunosorbent assay (ELISA). Clones exhibiting
a high affinity for the mollusk proteins were selected for production of soluble ScFv antibodies, which were purified for
subsequent analysis. ScFv antibodies exhibited a reaction specific for a protein whose molecular mass was about 15,000 Daltons
and that was detected by the antigen capture technique followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis
and Western blotting. 相似文献
140.
Charge-exchange reactions involving benzene have been successfully exploited to increase the sensitivity of atmospheric-pressure chemical ionization mass spectrometry (APCI-MS) towards hydrophobic compounds of significant environmental relevance which are not detectable with the ordinary APCI techniques. Among them, good sensitivity have been found for (a) highly chlorinated biphenyl derivatives such as dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethene (DDE); (b) cyclopentadienes such as Aldrin and its epoxy derivatives Dieldrin and Endrin; and (c) dibenzofurans and dibenzo-para-dioxins such as 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF) and 2,3,7,8-tetrachloro-dibenzo-para-dioxin (2,3,7,8-TCDD). The reactant benzene molecules were introduced into the source either through the nebulizer gas or by direct post-column addition of neat liquid, whereas the targeted compounds were analyzed using a high-performance liquid chromatography (HPLC) RP-18 column using methanol/water solutions as mobile phase. By using benzene as post-column reagent, positive ion mode detection was proven to be significantly enhanced as compared with APCI measurements carried out without benzene assistance. 相似文献