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Fátima H. Vaz Patrícia M. Machado Rita D. Brand?o Cátia T. Laranjeira Joana S. Eugénio Aires H. Fernandes Saudade P. André 《The journal of histochemistry and cytochemistry》2007,55(11):1105-1113
Only 20-25% of families screened for BRCA1/2 mutations are found positive. Because only a positive result is informative, we studied the role of BRCA1/2 immunohistochemistry as an additional method for patient selection. From 53 high-risk-affected probands, 18 (34%) had available paraffin blocks of their tumors and were selected for this study. Mutation screening was done by conformation-sensitive gel electrophoresis and multiplex ligation-dependent probe amplification. For immunohistochemistry, 21 neoplastic specimens (15 breast carcinomas, 5 ovary neoplasms, and 1 rectal adenocarcinoma) were analyzed with BRCA1 (monoclonal antibody, Ab-1, oncogene) and BRCA2 (polyclonal antibody, Ab-2, oncogene) antibodies. Absence of the BRCA1 protein was confirmed in negative tumors by Western blotting. Seven patients were positive for BRCA1/2 mutations: 5 for BRCA1 and 2 for BRCA2. Four out of five positive patients had tumors negative for BRCA1 immunostaining, and the remaining 13 BRCA1-negative patients had positive BRCA1 immunostaining in all tumor samples. Sensitivity to predict for BRCA1 mutation carriers was 80%, and specificity was 100%, with a positive predictive value of 100% and a negative predictive value of 93%. This correlation was statistically significant (p=0.001). No correlation was observed for BRCA2. If larger studies confirm these results, high-risk patients with BRCA1-negative tumors should be screened first for this gene. 相似文献
3.
Gabriela Caballero 《Morphology》2006,16(2):273-289
Although a wide array of phonological properties seem to backcopy in reduplication, it is an open question whether reduplicative
templates can backcopy as well. It has been argued that natural languages do not have reduplicative
constructions where the base truncates to match the truncated reduplicant (McCarthy & Prince, 1994; McCarthy & Prince, 1999;
Spaelti, 1997; inter alia). In Guarijio Abbreviated Reduplication (Miller, 1996), however, both copies of the reduplicative
construction truncate, instantiating the pattern that has been claimed not to exist. This paper argues that the Guarijio case
fills this typological gap. Although the data can be given a templatic backcopying analysis, this paper defends a Morphological
Doubling Theory (MDT) analysis using cophonologies (Inkelas & Zoll, 2005). In MDT, Guarijio Abbreviated Reduplication results
from the parallel imposition of a truncating cophonology in each copy of the reduplicative construction. Guarijio Abbreviated
Reduplication is predicted to exist by MDT together with other documented cases of parallel phonological modification in reduplication.
I am grateful to many people for helpful comments and suggestions, including Isabel Barreras Aguilar, Laura Downing, Nicholas
Fleisher, Andrew Garrett, Jason Haugen, Larry Hyman, Yuni Kim, Teresa McFarland, David Mortensen, Mary Paster, Eric Raimy,
and Timothy Thornes as well as the audience of the LSA 2005 Annual Meeting in Oakland. I would like to extend a special thanks
to Alan Yu for his detailed comments and suggestions to latter versions of this paper. I am particularly indebted to Sharon
Inkelas, for her generous advice, feedback, and numerous discussions throughout the development of this paper. I am also grateful
to two anonymous reviewers for their comments and criticisms, and especially to Ingo Plag for his patience and detailed suggestions
as editor. All remaining errors and omissions are mine. This study was made possible by fellowships by CONACYT (Consejo Nacional
de Ciencia y Tecnología, México), the University of California Institute for Mexico and the United States (UCMEXUS) and Fulbright. 相似文献
4.
5.
Determination of the critical micelle concentration of surfactants using the fluorescent probe N-phenyl-1-naphthylamine 总被引:4,自引:0,他引:4
The fluorescence quantum yield of N-phenyl-1-naphthylamine (NPN) increases about 10-fold and the wavelength of maximum fluorescence emission is blue-shifted when this molecule partitions into the apolar core of micellar structures from the aqueous phase. This property allowed the utilization of NPN as a fluorescent indicator of micelle formation by 14 different surfactants belonging to the families of alkyltrimethylammonium halides, alkylsulfates, alkylbetaines, alkylglucosides, and bile salts. The critical micelle concentrations (CMCs) determined with NPN agreed well with literature values. In this work NPN was used at a concentration of 10(-6) M which allowed determination of CMCs in the range between approximately 10(-5) and greater than 10(-2) M. With high-sensitivity instrumentation considerably lower NPN concentrations can be used and consequently considerably lower CMCs can be rapidly and accurately determined. 相似文献
6.
Felicitas Altmayr Gabriela Jusek Bernhard Holzmann 《The Journal of biological chemistry》2010,285(6):3525-3531
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Andreas Wagner Mirko Platzgummer Günther Kreismayr Heribert Quendler Gabriela Stiegler Boris Ferko 《Journal of liposome research》2013,23(3):311-319
A new scalable liposome production system is presented, which is based on the ethanol injection technique. The system permits liposome manufacture regardless of production scale, as scale is determined only by free disposable vessel volumes. Once the parameters are defined, an easy scale up can be performed by just changing the process vessels. These vessels are fully sterilizeable and all raw materials are transferred into the sanitized and sterilized system via 0.2 μm filters to guarantee an aseptic production.Liposome size can be controlled by the local lipid concentration at the injection point depending on process parameters like injection pressure, lipid concentration and injection rate. These defined process parameters are furthermore responsible for highly reproducible results with respect to vesicle diameters and encapsulation rates Compared to other technologies like the film method which is normally followed by size reduction through high pressure homogenization, ultrasonication or extrusion, no mechanical forces are needed to generate homogeneous and narrow distributed liposomes.Another important advantage of this method is the suitability for the entrapment of many different drug substances such as large hydrophilic proteins by passive encapsulation, small amphiphilic drugs by a one step remote loading technique or membrane association of antigens for vaccination approaches 相似文献
9.
10.
Teresa K. Aman Bruce A. Maki Thomas J. Ruffino Eileen M. Kasperek Gabriela K. Popescu 《The Journal of biological chemistry》2014,289(27):18805-18817
Protein kinase A (PKA) enhances synaptic plasticity in the central nervous system by increasing NMDA receptor current amplitude and Ca2+ flux in an isoform-dependent yet poorly understood manner. PKA phosphorylates multiple residues on GluN1, GluN2A, and GluN2B subunits in vivo, but the functional significance of this multiplicity is unknown. We examined gating and permeation properties of recombinant NMDA receptor isoforms and of receptors with altered C-terminal domain (CTDs) prior to and after pharmacological inhibition of PKA. We found that PKA inhibition decreased GluN1/GluN2B but not GluN1/GluN2A gating; this effect was due to slower rates for receptor activation and resensitization and was mediated exclusively by the GluN2B CTD. In contrast, PKA inhibition reduced NMDA receptor-relative Ca2+ permeability (PCa/PNa) regardless of the GluN2 isoform and required the GluN1 CTD; this effect was due primarily to decreased unitary Ca2+ conductance, because neither Na+ conductance nor Ca2+-dependent block was altered substantially. Finally, we show that both the gating and permeation effects can be reproduced by changing the phosphorylation state of a single residue: GluN2B Ser-1166 and GluN1 Ser-897, respectively. We conclude that PKA effects on NMDA receptor gating and Ca2+ permeability rely on distinct phosphorylation sites located on the CTD of GluN2B and GluN1 subunits. This separate control of NMDA receptor properties by PKA may account for the specific effects of PKA on plasticity during synaptic development and may lead to drugs targeted to alter NMDA receptor gating or Ca2+ permeability. 相似文献