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61.
Location of the active site of the bean {alpha}-amylase inhibitor and involvement of a Trp, Arg, Tyr triad 总被引:1,自引:0,他引:1
Mirkov T.Erik; Evans Stephen V.; Washlstrom Janice; Gomez Luis; Young N.Martin; Chrispeels Maarten J. 《Glycobiology》1995,5(1):45-50
Seeds of the common bean contain three homologous proteins:phytohaemagglutinin E, phytohaemagglutinin L and the lectin-likeprotein 相似文献
62.
63.
Olga P. Nyssen Angeles Perez‐Aisa Luis Rodrigo Manuel Castro Pilar Mata Romero Juan Ortuo Jesus Barrio Jose Maria Huguet Ines Modollel Noelia Alcaide Alfredo Lucendo Xavier Calvet Monica Perona Barbara Gomez Blas Jose Gomez Rodriguez Pilar Varela Manuel Jimenez‐Moreno Manuel Dominguez‐Cajal Liliana Pozzati Diego Burgos Luis Bujanda Jenifer Hinojosa Javier Molina‐Infante Tommaso Di Maira Luis Ferrer Luis Fernndez‐Salazar Ariadna Figuerola Llucia Tito Cristobal de la Coba Judith Gomez‐Camarero Nuria Fernandez Maria Caldas Ana Garre Elena Resina Ignasi Puig Colm OMorain Francis Megraud Javier P. Gisbert 《Helicobacter》2020,25(5)
64.
Comparative analysis reveals amino acids critical for anticancer activity of peptide CIGB‐552 下载免费PDF全文
Soledad Astrada Yolanda Gomez Exequiel Barrera Gonzalo Obal Otto Pritsch Sergio Pantano Maribel G. Vallespí Mariela Bollati‐Fogolín 《Journal of peptide science》2016,22(11-12):711-722
Because of resistance development by cancer cells against current anticancer drugs, there is a considerable interest in developing novel antitumor agents. We have previously demonstrated that CIGB‐552, a novel cell‐penetrating synthetic peptide, was effective in reducing tumor size and increasing lifespan in tumor‐bearing mice. Studies of protein–peptide interactions have shown that COMMD1 protein is a major mediator of CIGB‐552 antitumor activity. Furthermore, a typical serine‐protease degradation pattern for CIGB‐552 in BALB/c mice serum was identified, yielding peptides which differ from CIGB‐552 in size and physical properties. In the present study, we show the results obtained from a comparative analysis between CIGB‐552 and its main metabolites regarding physicochemical properties, cellular internalization, and their capability to elicit apoptosis in MCF‐7 cells. None of the analyzed metabolites proved to be as effective as CIGB‐552 in promoting apoptosis in MCF‐7. Taking into account these results, it seemed important to examine their cell‐penetrating capacity and interaction with COMMD1. We show that internalization, a lipid binding‐dependent process, is impaired as well as metabolite–COMMD1 interaction, key component of the apoptotic mechanism. Altogether, our results suggest that features conferred by the amino acid sequence are decisive for CIGB‐552 biological activity, turning it into the minimal functional unit. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
65.
Abel Barral Bernard Gomez Juan M. Zorrilla José M. Serrano Johan Yans Véronique Daviero‐Gomez Timothy A.M. Ewin Christophe Lécuyer 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2017,50(2):244-257
Two plant fossil‐bearing beds from the middle Barremian of Belgium were analysed to ascertain how experimental designs affect conclusions regarding palaeodiversity at a local scale. We analysed eight lateral samples per bed taken regularly every 3 m using an exhaustive sub‐sampling method. The Clench equation was used to evaluate the completeness of the taxonomic inventory of the samples and the sampling effort needed to obtain a reliable representation of diversity. The number of replicates needed to obtain the same representation of diversity from different nearby lateral samples of the same bed ranged from 5 to 19. Richness (S), Evenness (J) and the number of equiprobable taxa (2H’) greatly varied between samples from the same bed, even over short distances. Only one of the studied samples was representative of the taxonomic inventory of its bed. Our study shows that 1) the selection bias of the sampling area is reduced by increasing the number of lateral samples taken in a bed, enabling more reliable conclusions about local‐scale diversity; 2) intense sub‐sampling methods are needed to account for statistically independent observations of detailed lateral variation; and 3) sampling methods in palaeodiversity analyses must look for a similar degree of representativeness in samples rather than a homogeneous sample size. Using a sampling effort analysis provides evidence for the completeness of the data set, adjusting the amount of work required. Implementing the Clench equation in palaeodiversity analyses improves the performance of data acquisition in palaeoecological studies and provides a quality test of the data sets derived from them. 相似文献
66.
Matthew P. Rowan Sonya M. Bierbower Michael A. Eskander Kalina Szteyn Elaine D. Por Ruben Gomez Nicholas Veldhuis Nigel W. Bunnett Nathaniel A. Jeske 《PloS one》2014,9(4)
The transient receptor potential family V1 channel (TRPV1) is activated by multiple stimuli, including capsaicin, acid, endovanilloids, and heat (>42C). Post-translational modifications to TRPV1 result in dynamic changes to the sensitivity of receptor activation. We have previously demonstrated that β-arrestin2 actively participates in a scaffolding mechanism to inhibit TRPV1 phosphorylation, thereby reducing TRPV1 sensitivity. In this study, we evaluated the effect of β-arrestin2 sequestration by G-protein coupled receptors (GPCRs) on thermal and chemical activation of TRPV1. Here we report that activation of mu opioid receptor by either morphine or DAMGO results in β-arrestin2 recruitment to mu opioid receptor in sensory neurons, while activation by herkinorin does not. Furthermore, treatment of sensory neurons with morphine or DAMGO stimulates β-arrestin2 dissociation from TRPV1 and increased sensitivity of the receptor. Conversely, herkinorin treatment has no effect on TRPV1 sensitivity. Additional behavioral studies indicate that GPCR-driven β-arrestin2 sequestration plays an important peripheral role in the development of thermal sensitivity. Taken together, the reported data identify a novel cross-talk mechanism between GPCRs and TRPV1 that may contribute to multiple clinical conditions. 相似文献
67.
Diniz PH Silva JH Gomez MV Guatimosim C Gomez RS 《Cellular and molecular neurobiology》2007,27(6):757-770
Experimental data suggest that halothane anesthesia is associated with significant changes in dopamine (DA) concentration
in some brain regions but the mechanism of this effect is not well known. Rat brain cortical slices were labeled with [3H]DA to further characterize the effects of halothane on the release of this neurotransmitter from the central nervous system.
Halothane induced an increase on the release of [3H]DA that was dependent on incubation time and anesthetic concentration (0.012, 0.024, 0.048, 0.072 and 0.096 mM). This effect
was independent of extracellular or intracellular calcium. In addition, [3H]DA release evoked by halothane was not affected by TTX (blocker of voltage-dependent Na+ channels) or reserpine (a blocker of vesicular monoamine transporter). These data suggest that [3H]DA release induced by halothane is non-vesicular and would be mediated by the dopamine transporter (DAT) and norepinephrine
transporter (NET). GBR 12909 and nomifensine, inhibitors of DAT, decreased the release of [3H]DA evoked by halothane. Nisoxetine, a blocker of NET, reduced the release of [3H]DA induced by halothane. In addition, GBR 12909, nisoxetine and, halothane decrease the uptake of [3H]DA into rat brain cortical slices. A decrease on halothane-induced release of [3H]DA was also observed when the brain cortical slices were incubated at low temperature and low extracellular sodium, which
are known to interfere with the carrier-mediated release of the neurotransmitter. Ouabain, a Na+/K+ ATPase pump inhibitor, which induces DA release through reverse transport, decreased [3H]DA release induced by halothane. It is suggested that halothane increases [3H]DA release in brain cortical slices that is mediated by DAT and NET present in the plasma membrane. 相似文献
68.
Thai Leong Yap Zhiping Jiang Frank Heinrich James M. Gruschus Candace M. Pfefferkorn Marilia Barros Joseph E. Curtis Ellen Sidransky Jennifer C. Lee 《The Journal of biological chemistry》2015,290(2):744-754
Mutations in glucocerebrosidase (GCase), the enzyme deficient in Gaucher disease, are a common genetic risk factor for the development of Parkinson disease and related disorders, implicating the role of this lysosomal hydrolase in the disease etiology. A specific physical interaction exists between the Parkinson disease-related protein α-synuclein (α-syn) and GCase both in solution and on the lipid membrane, resulting in efficient enzyme inhibition. Here, neutron reflectometry was employed as a first direct structural characterization of GCase and α-syn·GCase complex on a sparsely-tethered lipid bilayer, revealing the orientation of the membrane-bound GCase. GCase binds to and partially inserts into the bilayer with its active site most likely lying just above the membrane-water interface. The interaction was further characterized by intrinsic Trp fluorescence, circular dichroism, and surface plasmon resonance spectroscopy. Both Trp fluorescence and neutron reflectometry results suggest a rearrangement of loops surrounding the catalytic site, where they extend into the hydrocarbon chain region of the outer leaflet. Taking advantage of contrasting neutron scattering length densities, the use of deuterated α-syn versus protiated GCase showed a large change in the membrane-bound structure of α-syn in the complex. We propose a model of α-syn·GCase on the membrane, providing structural insights into inhibition of GCase by α-syn. The interaction displaces GCase away from the membrane, possibly impeding substrate access and perturbing the active site. GCase greatly alters membrane-bound α-syn, moving helical residues away from the bilayer, which could impact the degradation of α-syn in the lysosome where these two proteins interact. 相似文献
69.
André Breton Brigitte Gaillard-Martine Corinne Gerbi Béatrice Gomez de Ségura Roger Durand Belgacem Kherratia 《Current microbiology》1995,31(4):224-227
-d-Glucosidase, -d-fucosidase -d-xylosidase, and -cellobiopyranosidase activities in Caecomyces communis, Neocallimastix frontalis, and Piromyces rhizinflata, located with fluorescent conjugates, occur throughout the whole thallus as from zoospore germination and disappear before sporulation. -d-Galactosidase and -l-arabinopyranosidase activities are low or nonexistent. A xylanase, detected by indirect immunofluorescence, was observed at the surface of the vegetative cells, vesicles, or rhizoids. Cross-reactions prove the existence of analogies in structure among the enzymes of these anaerobic gut fungi. 相似文献
70.
Anna Santoro Javier Conde Morena Scotece Vanessa Abella Ana Lois Veronica Lopez Jesus Pino Rodolfo Gomez Juan J. Gomez-Reino Oreste Gualillo 《PloS one》2015,10(8)