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71.
Loconto J Papes F Chang E Stowers L Jones EP Takada T Kumánovics A Fischer Lindahl K Dulac C 《Cell》2003,112(5):607-618
The vomeronasal organ (VNO) of the mouse has two neuronal compartments expressing distinct families of pheromone receptors, the V1Rs and the V2Rs. We report here that two families of major histocompatibility complex (MHC) class Ib molecules, the M10 and the M1 families, show restricted expression in V2R-expressing neurons. Our data suggest that neurons expressing a given V2R specifically co-express one or a few members of the M10 family. Biochemical and immunocytochemical analysis demonstrates that in VNO sensory dendrites M10s belong to large multi-molecular complexes that include pheromone receptors and beta2-microglobulin (beta2m). In cultured cells, M10s appear to function as escort molecules in transport of V2Rs to the cell surface. Accordingly, beta2m-deficient mice exhibit mislocalization of V2Rs in the VNO and a specific defect in male-male aggressive behavior. The functional characterization of M10 highlights an unexpected role for MHC molecules in pheromone detection by mammalian VNO neurons. 相似文献
72.
73.
Proteins from bovine tissues and biological fluids: defining a reference electrophoresis map for liver,kidney, muscle,plasma and red blood cells 总被引:1,自引:0,他引:1
Talamo F D'Ambrosio C Arena S Del Vecchio P Ledda L Zehender G Ferrara L Scaloni A 《Proteomics》2003,3(4):440-460
A number of high resolution two-dimensional electrophoresis (2-DE) reference maps for bovine tissues and biological fluids have been determined for animals in basal state. Among the 1863 distinct protein features detected in samples of liver, kidney, muscle, plasma and red blood cells, 509 species were identified and associated to 209 different genes. Difficulties in the identification were related to the poorly characterized Bos taurus genome and were solved by a combined matrix-assisted laser desorption/ionisation-mass spectrometry and liquid chromatography-electrospray ionization tandem mass spectrometry approach. The experimental output allowed us to establish a 2-DE database accessible through the World Wide Web network at the URL address (http://www.iabbam.na.cnr.it/Biochem). These reference maps may serve as a tool in future veterinary medical studies aimed at the evaluation of changes in protein repertoire for altered animal physiological conditions and infectious diseases, to the definition of molecular markers for novel diagnostic kits and vaccines, as well as the characterization of protein modifications in bovine materials following technological processes used in the food industry. 相似文献
74.
75.
de Champdoré M De Napoli L Di Fabio G Messere A Montesarchio D Piccialli G 《Nucleosides, nucleotides & nucleic acids》2003,22(5-8):695-697
An easy and efficient strategy to obtain new nucleoside based solid supports in which the nucleoside moieties have been anchored to the solid support through the nucleobase is here proposed. A simple and efficient solid-phase synthesis of 5' and 3'-derivatized uridine analogues has so been developed, following methodologies well established in organic chemistry. 相似文献
76.
77.
Di Fabio R Tranquillini E Bertani B Alvaro G Micheli F Sabbatini F Pizzi MD Pentassuglia G Pasquarello A Messeri T Donati D Ratti E Arban R Dal Forno G Reggiani A Barnaby RJ 《Bioorganic & medicinal chemistry letters》2003,13(21):3863-3866
To identify neuroprotective agents after stroke, new substituted tetrahydroquinoline derivatives were designed as antagonists of the glycine binding site associated to the NMDA receptor, satisfying the key pharmacophoric requirements. In particular, the racemate 3c exhibited outstanding in vivo activity in the MCAo model in rats, when given iv both pre- and post-ischemia. Pure enantiomers 3c-(+) and 3c-(-) have been prepared following an original synthetic route. Despite the significant difference of activity observed in vitro, they shown similar neuroprotective profile in the MCAo model in rats. 相似文献
78.
Martire M D'Amico M Panza E Miceli F Viggiano D Lavergata F Iannotti FA Barrese V Preziosi P Annunziato L Taglialatela M 《Journal of neurochemistry》2007,102(1):179-193
KCNQ2 and KCNQ3 subunits encode for the muscarinic-regulated current (I(KM)), a sub-threshold voltage-dependent K+ current regulating neuronal excitability. In this study, we have investigated the involvement of I(KM) in dopamine (DA) release from rat striatal synaptosomes evoked by elevated extracellular K+ concentrations ([K+]e) and by muscarinic receptor activation. [3H]dopamine ([3H]DA) release triggered by 9 mmol/L [K+]e was inhibited by the I(KM) activator retigabine (0.01-30 micromol/L; Emax = 54.80 +/- 3.85%; IC50 = 0.50 +/- 0.36 micromol/L). The I(KM) blockers tetraethylammonium (0.1-3 mmol/L) and XE-991 (0.1-30 micromol/L) enhanced K+-evoked [3H]DA release and prevented retigabine-induced inhibition of depolarization-evoked [3H]DA release. Retigabine-induced inhibition of K+-evoked [3H]DA release was also abolished by synaptosomal entrapment of blocking anti-KCNQ2 polyclonal antibodies, an effect prevented by antibody pre-absorption with the KCNQ2 immunizing peptide. Furthermore, the cholinergic agonist oxotremorine (OXO) (1-300 micromol/L) potentiated 9 mmol/L [K+]e-evoked [3H]DA release (Emax = 155 +/- 9.50%; EC50 = 25 +/- 1.80 micromol/L). OXO (100 micromol/L)-induced [3H]DA release enhancement was competitively inhibited by pirenzepine (1-10 nmol/L) and abolished by the M3-preferring antagonist 4-diphenylacetoxy N-methylpiperidine methiodide (1 micromol/L), but was unaffected by the M1-selective antagonist MT-7 (10-100 nmol/L) or by Pertussis toxin (1.5-3 microg/mL), which uncouples M2- and M4-mediated responses. Finally, OXO-induced potentiation of depolarization-induced [3H]DA release was not additive to that produced by XE-991 (10 micromol/L), was unaffected by retigabine (10 micromol/L), and was abolished by synaptosomal entrapment of anti-KCNQ2 antibodies. Collectively, these findings indicate that, in rat striatal nerve endings, I(KM) channels containing KCNQ2 subunits regulate depolarization-induced DA release and that I(KM) suppression is involved in the reinforcement of depolarization-induced DA release triggered by the activation of pre-synaptic muscarinic heteroreceptors. 相似文献
79.
Katiucia Batista Silva Paiva Willian Fernando Zambuzzi Thais Accorsi-Mendonça Rumio Taga Fabio Daumas Nunes Mari Cleide Sogayar José Mauro Granjeiro 《Journal of molecular histology》2009,40(3):201-207
Reversion-inducing-cysteine-rich protein with Kazal motifs (RECK) is a single membrane-anchored MMP-regulator and regulates
matrix metalloproteinases (MMP) 2, 9 and 14. In turn, MMPs are endopeptidases that play a pivotal role in remodeling ECM.
In this work, we decided to evaluate expression pattern of RECK in growing rat incisor during, specifically focusing out amelogenesis
process. Based on different kinds of ameloblasts, our results showed that RECK expression was conducted by secretory and post-secretory
ameloblasts. At the secretory phase, RECK was localized in the infra-nuclear region of the ameloblast, outer epithelium, near
blood vessels, and in the stellate reticulum. From the transition to the maturation phases, RECK was strongly expressed by
non-epithelial immuno-competent cells (macrophages and/or dendritic-like cells) in the papillary layer. From the transition
to the maturation stage, RECK expression was increased. RECK mRNA was amplified by RT-PCR from whole enamel organ. Here, we
verified the presence of RECK mRNA during all stages of amelogenesis. These events were governed by ameloblasts and by non-epithelial
cells residents in the enamel organ. Concluding, we found differential expression of MMPs-2, -9 and RECK in the different
phases of amelogenesis, suggesting that the tissue remodeling is rigorously controlled during dental mineralization. 相似文献
80.
Claudio Lera Orsatti Eliana Aguiar Petri Nahas Jorge Nahas-Neto Fabio Lera Orsatti Vanessa Innocenti Giorgi Steven S. Witkin 《PloS one》2014,9(10)