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991.
Florence Quesada Calvo Marianne Fillet Dr. Dominique de Seny Marie‐Alice Meuwis Raphael Maree Céline Crahay Geneviève Paulissen Natacha Rocks Maud Gueders Louis Wehenkel Marie‐Paule Merville Renaud Louis Jean‐Michel Foidart Agnes Noël Didier Cataldo 《Proteomics》2009,9(8):2163-2170
Asthma is a complex inflammatory disease of airways. A network of reciprocal interactions between inflammatory cells, peptidic mediators, extracellular matrix components, and proteases is thought to be involved in the installation and maintenance of asthma‐related airway inflammation and remodeling. To date, new proteic mediators displaying significant activity in the pathophysiology of asthma are still to be unveiled. The main objective of this study was to uncover potential target proteins by using surface‐enhanced laser desorption/ionization‐time of flight‐mass spectrometry (SELDI‐TOF‐MS) on lung samples from mouse models of allergen‐induced airway inflammation and remodeling. In this model, we pointed out several protein or peptide peaks that were preferentially expressed in diseased mice as compared to controls. We report the identification of different five proteins: found inflammatory zone 1 or RELMα (FIZZ‐1), calcyclin (S100A6), clara cell secretory protein 10 (CC10), Ubiquitin, and Histone H4. 相似文献
992.
993.
Christian Schloegl Anneke Dierks Gyula K. Gajdon Ludwig Huber Kurt Kotrschal Thomas Bugnyar 《PloS one》2009,4(8)
Background
Among birds, corvids and parrots are prime candidates for advanced cognitive abilities. Still, hardly anything is known about cognitive similarities and dissimilarities between them. Recently, exclusion has gained increasing interest in comparative cognition. To select the correct option in an exclusion task, one option has to be rejected (or excluded) and the correct option may be inferred, which raises the possibility that causal understanding is involved. However, little is yet known about its evolutionary history, as only few species, and mainly mammals, have been studied.Methodology/Principal Findings
We tested ravens and keas in a choice task requiring the search for food in two differently shaped tubes. We provided the birds with partial information about the content of one of the two tubes and asked whether they could use this information to infer the location of the hidden food and adjust their searching behaviour accordingly. Additionally, this setup allowed us to investigate whether the birds would appreciate the impact of the shape of the tubes on the visibility of food. The keas chose the baited tube more often than the ravens. However, the ravens applied the more efficient strategy, choosing by exclusion more frequently than the keas. An additional experiment confirmed this, indicating that ravens and keas either differ in their cognitive skills or that they apply them differently.Conclusion
To our knowledge, this is the first study to demonstrate that corvids and parrots may perform differently in cognitive tasks, highlighting the potential impact of different selection pressures on the cognitive evolution of these large-brained birds. 相似文献994.
Hiromi Hosako Gail S. Martin Marianne Barrier Yian A. Chen Ivan V. Ivanov Philip E. Mirkes 《Birth defects research. Part A, Clinical and molecular teratology》2009,85(6):546-555
BACKGROUND: Neural tube defects (NTDs) are one of the most common human birth defects, with a prevalence of approximately 1 in 1000 live births in the United States. In animal studies, deletion of p53 leads to a significant increase in embryos that exhibit exencephaly. Whereas several studies have closely investigated the morphologic changes of p53‐deficient embryos, no study has reported the molecular‐level alteration in p53‐deficient embryos. Here we attempt to identify genes and microRNAs (miRNAs) modified by deletion of p53 in day 8.5 mouse embryos. METHODS: Mouse embryos from p53 heterozygous crosses were collected, genotyped, and embryos of similar genotype (+/+; +/?; ?/?) were pooled. RNA from the pooled samples was isolated to determine mRNA and miRNA expression levels using Whole Genome Bioarrays and Low Density Arrays, respectively. RESULTS: In p53 ?/? embryos, 388 genes showed statistically significant alteration in gene expression of more than twofold compared to p53 +/+ embryos. Expression of p53 and well known p53 target genes, such as p21 and cyclin G1, were significantly down‐regulated in p53 ?/? embryos. In contrast, expression of other p53 target genes, such as Mdm2, Noxa, and Puma, were unchanged. We also identified six genes (Csk, Itga3, Jarid2, Prkaca, Rarg, and Sall4), known to cause NTDs when deleted, that are also down‐regulated in p53 ?/? embryos. Finally, five miRNAs (mir‐1, mir‐30e‐3p, mir‐142‐3p, mir‐301, and mir‐331) also showed statistically significant alterations in expression levels in p53 ?/? embryos compared to p53 +/+ embryos. Combined analysis of the experimental data using stepwise regression model and two publicly available algorithms identified putative target genes of these miRNAs. CONCLUSIONS: Our data have identified genes and miRNAs that may be involved in the mechanisms underlining NTDs and begin to define the developmental role of p53 in the etiology of NTDs. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc. 相似文献
995.
Yuuichi Soeno Yuji Taya Taras Stasyk Lukas A. Huber Takaaki Aoba Alexander Hüttenhofer 《RNA (New York, N.Y.)》2010,16(7):1293-1300
Small nucleolar RNAs (snoRNAs) guide nucleotide modifications within ribosomal RNAs or spliceosomal RNAs by base-pairing to complementary regions within their RNA targets. The brain-specific snoRNA MBII-52 lacks such a complementarity to rRNAs or snRNAs, but instead has been reported to target the serotonin receptor 2C pre-mRNA, thereby regulating pre-mRNA editing and/or alternative splicing. To understand how the MBII-52 snoRNA might be involved in these regulatory processes, we isolated the MBII-52 snoRNP from total mouse brain by an antisense RNA affinity purification approach. Surprisingly, by mass spectrometry we identified 17 novel candidates for MBII-52 snoRNA binding proteins, which previously had not been reported to be associated with canonical snoRNAs. Among these, Nucleolin and ELAVL1 proteins were confirmed to independently and directly interact with the MBII-52 snoRNA by coimmunoprecipitation. Our findings suggest that the MBII-52 snoRNA assembles into novel RNA-protein complexes, distinct from canonical snoRNPs. 相似文献
996.
997.
Tamulaitiene G Jakubauskas A Urbanke C Huber R Grazulis S Siksnys V 《Structure (London, England : 1993)》2006,14(9):1389-1400
Rare-cutting restriction enzymes are important tools in genome analysis. We report here the crystal structure of SdaI restriction endonuclease, which is specific for the 8 bp sequence CCTGCA/GG ("/" designates the cleavage site). Unlike orthodox Type IIP enzymes, which are single domain proteins, the SdaI monomer is composed of two structural domains. The N domain contains a classical winged helix-turn-helix (wHTH) DNA binding motif, while the C domain shows a typical restriction endonuclease fold. The active site of SdaI is located within the C domain and represents a variant of the canonical PD-(D/E)XK motif. SdaI determinants of sequence specificity are clustered on the recognition helix of the wHTH motif at the N domain. The modular architecture of SdaI, wherein one domain mediates DNA binding while the other domain is predicted to catalyze hydrolysis, distinguishes SdaI from previously characterized restriction enzymes interacting with symmetric recognition sequences. 相似文献
998.
Rohr KB Selwood T Marquardt U Huber R Schechter NM Bode W Than ME 《Journal of molecular biology》2006,357(1):195-209
Tryptases alpha and beta are trypsin-like serine proteinases expressed in large amounts by mast cells. Beta-tryptase is a tetramer that has enzymatic activity, but requires heparin binding to maintain functional and structural stability, whereas alpha-tryptase has little, if any, enzymatic activity but is a stable tetramer in the absence of heparin. As shown previously, these differences can be mainly attributed to the different conformations of the 214-220 segment. Interestingly, the replacement of Asp216 by Gly, which is present in beta-tryptase, results in enzymatically active but less stable alpha-tryptase mutants. We have solved the crystal structures of both the single (D216G) and the double (K192Q/D216G) mutant forms of recombinant human alphaI-tryptase in complex with the peptide inhibitor leupeptin, as well as the structure of the non-inhibited single mutant. The inhibited mutants exhibited an open functional substrate binding site, while in the absence of an inhibitor, the open (beta-tryptase-like) and the closed (alpha-tryptase-like) conformations were present simultaneously. This shows that both forms are in a two-state equilibrium, which is influenced by the residues in the vicinity of the active site and by inhibitor/substrate binding. Novel insights regarding the observed stability differences as well as a potential proteolytic activity of wild-type alpha-tryptase, which may possess a cryptic active site, are discussed. 相似文献
999.
Jér?me Toussaint Virginie Durbecq Sevilay Altintas Valérie Doriath Ghizlane Rouas Marianne Paesmans Philippe Bedard Benjamin Haibe-Kains Wiebren A. Tjalma Denis Larsimont Martine Piccart Christos Sotiriou 《PloS one》2010,5(8)
Purpose
Optimal management of breast ductal carcinoma in situ (DCIS) is controversial, and many patients are still overtreated. The local death of myoepithelial cells (MECs) is believed to be a pre-requisite to tumor invasion. We thus hypothesized that loss of CD10 expression, a MEC surface peptidase, would signify basement membrane disruption and confer increased risk of relapse in DCIS. The aim of our study was to retrospectively evaluate the prognostic value of CD10 in DCIS.Experimental Design
CD10 expression was evaluated by quantitative RT-PCR and immunohistochemistry using paraffin-embedded samples of normal breast tissue (n = 11); of morphologically normal ducts associated with DCIS (n = 10); and of DCIS without an invasive component (n = 154).Results
CD10 immunostaining was only observed in MECs in normal tissue and in DCIS. Normal tissue showed high mRNA expression levels of CD10, whereas DCIS showed a variable range. After a median follow-up of 6 years, DCIS with CD10 expression below the levels observed in normal tissue (71%) demonstrated a higher risk of local relapse (HR = 1.88; [95CI:1.30–2.70], p = 0.001) in univariate analysis. No relapse was observed in patients expressing high CD10 mRNA levels (29%) similar to the ones observed in normal tissue. In multivariate analysis including known prognostic factors, low CD10 mRNA expression remained significant (HR = 2.25; [95%CI:1.24–4.09], p = 0.008), as did the recently revised Van Nuys Prognostic Index (VNPI) score (HR = 2.03; [95%CI:1.23–3.35], p = 0.006).Conclusion
The decrease of CD10 expression in MECs is associated with a higher risk of relapse in DCIS; this knowledge has the potential to improve DCIS management. 相似文献1000.
Patricia Guillaumot Céline Luquain Mouhannad Malek Anne-Laure Huber Sabine Brugière Jérome Garin Didier Grunwald Daniel Régnier Virginie Pétrilli Etienne Lefai Serge N. Manié 《PloS one》2010,5(6)