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101.
Gerwen Lammers Günter Roth Mathias Heck Roland Zengerle G. Sandra Tjabringa Elly M. Versteeg Theo Hafmans Ronnie Wismans Dieter P. Reinhardt Eugene T. P. Verwiel Patrick L. J. M. Zeeuwen Joost Schalkwijk Roland Brock Willeke F. Daamen Toin H. van Kuppevelt 《Macromolecular bioscience》2012,12(5):675-691
A papillary‐structured collagen fibril membrane is created, mimicking the 3D‐architecture of the human papillary dermis. Primary human keratinocytes cultured to confluency on papillar‐structured films are compared to keratinocytes cultured on flat membranes. Microscopical evaluation reveals the presence of morphologically distinct cells at the base of the papillar structures that are not observed on flat membranes. Gene expression microarrays and RT‐qPCR indicate that these cells are in a more proliferative/migrational state, whereas cells on flat membranes have a more differentiated expression profile. Immunohistochemical stainings confirm these results. In conclusion, specific collagen architecture can direct keratinocyte behavior, and this may be used to further improve skin regeneration.
102.
MA Smith M Coinçon A Paschos B Jolicoeur P Lavallée J Sygusch C Baron 《Chemistry & biology》2012,19(8):1041-1048
Secretion systems translocate virulence factors of many bacterial pathogens, enabling their survival inside the host organism. Consequently, inhibition strongly attenuates pathogenicity and can be considered a target for novel antimicrobial drugs. The type IV secretion system (T4SS) of the intracellular pathogen Brucella is a prerequisite for its virulence, and in this work we targeted the interactions of the?essential assembly factor protein, VirB8, using small-molecule inhibitors. High-throughput screening identified several potent and specific inhibitors, and the target-binding site of these inhibitors was identified by X-ray crystallography, in?silico docking, and analysis of the derivates of the inhibitor B8I-2. VirB8 interaction inhibitors bind to a surface groove opposite to the dimerization interface, and by varying the binding-site residues, we were able to determine which residues are required for inhibitor activity. E115 and K182 were found to be especially important, and changes at R114, Y229, and L151 also reduced inhibitor efficiency. 相似文献
103.
The supramolecular assembly of Helicobacter pylori urease was studied by nanoflow electrospray ionization orthogonal time-of-flight mass spectrometry. The measured molecular mass of the urease complex of 1.06 MDa corresponds to a dodecameric (alphabeta)(12) assembly of urease alpha (26 kDa) and beta (61 kDa) subunits. The dodecamer disassembles readily into (alphabeta)(3) subunits in solution and under controlled collisional-induced dissociation in the gas phase. This is in strong support of an ((alphabeta)(3))(4) architecture consistent with the recently published x-ray structure. In vitro, the alpha and beta subunits are capable of re-assembling to (alphabeta)(3), but not further to the dodecameric complex. 相似文献
104.
105.
This paper discusses the molecular design of selected examples of structural units containing taper shaped exo-receptors and various crown ether, oligooxyethylenic, and H-bonding based endo-receptors, which self-assemble into cylindrical channel-like architectures via principles resembling those of tobacco mosaic virus (TMV). The ability of these structural units to self- assemble via a delicate combination of exo-and endo-recognition processes will be presented. A comparison between various supramolecular (generated via H-bonding, ionic, and electrostatic interactions) and molecular “polymer backbones” will be made. The present limitations concerning the ability to engineer the structural parameters of these supramolecular channel-like architectures and some possible novel material functions derived from them will be briefly mentioned. 相似文献
106.
Albert J. R. Heck Leo J. de Koning Nice M. M. Nibbering 《Journal of the American Society for Mass Spectrometry》1991,2(6):453-458
Results of a Fourier transform-ion cyclotron resonance study are reported concerning the reactivity of protonated perdeuteromethane and deuteronated methane, generated under varying pressure conditions in an external chemical ionization ion source, toward ammonia. The competition between proton and deuteron transfer from both protonated perdeuteromethane and deuteronated methane to ammonia exhibits chemically distinguishable hydrogens. The chemical behavior of protonated methane appears to be compatible with the theoretically predicted stable structure with CS symmetry, involving a three-center two-electron bond associating two hydrogens and the carbon atom. Interconversion of this structure due to exchange between one of these hydrogens and one of the three remaining hydrogens appears to be a fast process that is induced by interactions with the chemical ionization gas. 相似文献
107.
Bächler J Bartke J Bialkowska H Bock R Brockmann R Buncic P Chase SI Derado I Eckardt V Eschke J Ferenc D Fleischmann B Foka P Fuchs M Gazdzicki M Gladysz E Harris JW Heck W Hoffmann M Jacobs PM Kabana S Kadija K Keidel R Kosiec J Kowalski M Kühmichel A Lahanas M Lee JY Ljubicic A Margetis S Morse R Nappi E Odyniec G Paic G Panagiotu AD Petridis A Piper A Posa F Poskanzer AM Pugh HG Pühlhofer F Rai G Rauch W Renfordt R Röhrich D Roland G Rothard H Runge K Sandoval A Schambach JJ Schmitz N 《Physical review letters》1994,72(10):1419-1422
108.
D. K-H. Finkler T. Heck A. E. Maurer S. J. Campbell U. Gonser 《Hyperfine Interactions》1988,41(1):571-574
TheCuAuFe system has been studied by room temperature Mössbauer spectroscopy in order to examine the influence of varying both iron (Cu94?yAu6Fey; y=0.2–1.0 at%) and gold (Cu99?xAuxFe1; x=6–50.7 at%) concentrations on the clustering of iron atoms. Samples were examined in different metallurgical states, as rolled, fast quenched and melt spun with similar degrees of clustering being observed. The isomer shift is found to vary inversely with atomic volume for the Cu99?xAuxFe1 alloys. 相似文献
109.
110.
van den Bremer ET Keeble AH Kleanthous C Heck AJ 《Chemical communications (Cambridge, England)》2005,(9):1137-1139
Mass spectrometric and calorimetric data reveal that phosphate ion binding to the active site of colicin E9 DNase is delicately regulated by concomitant binding of specific transition metal ions. 相似文献