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141.
Increased levels of macrophage migration inhibitory factor (MIF) in serum, sputum, and bronchioalveolar lavage fluid (BALF) from asthmatic patients and time/dose-dependent expression of MIF in eosinophils in response to phorbol myristate acetate suggest the participation of MIF in airway inflammation. In this study, we examined inflammation in OVA-sensitized mouse lungs in wild-type and MIF-deficient mice (MIF(-/-)). We report increased MIF in the lung and BALF of sensitized wild-type mice. MIF(-/-) mice demonstrated significant reductions in serum IgE and alveolar inflammatory cell recruitment. Reduced Th1/Th2 cytokines and chemokines also were detected in serum or BALF from MIF(-/-) mice. Importantly, alveolar macrophages and mast cells, but not dendritic cells or splenocytes, from MIF(-/-) mice demonstrated impaired CD4+ T cell activation, and the reconstitution of wild-type mast cells in MIF(-/-) mice restored the phenotype of OVA-induced airway inflammation, revealing a novel and essential role of mast cell-derived MIF in experimentally induced airway allergic diseases.  相似文献   
142.
In acute and chronic schistosomiasis, survival of the host requires a carefully balanced immune response against highly immunogenic parasite eggs. We characterized the phenotype, distribution, and functional role of CD4(+)Foxp3(+) naturally occurring regulatory T cells (naTregs) in schistosome egg-induced inflammation. In adoptive transfer experiments and by intracellular staining for Foxp3, we demonstrate significant frequencies of naTregs in hepatic granulomas and draining lymphoid tissues of mice infected with the trematode Schistosoma mansoni. Strikingly, egg-induced inflammation does not change the normal ratio between naTregs and effector CD4(+) T cells at the inflammatory site or in lymphoid organs in acute or chronic disease. However, increasing frequencies of CD103-expressing cells in the naTreg compartment indicate a change in phenotype for naTregs with disease progression. Because CD103 was described recently as an activation marker for naTregs, we speculate that naTregs in chronic schistosomiasis are potentially more suppressive. Furthermore, we found that most naTregs do not contribute to egg-induced IL-4 and IL-10 production. Importantly, depletion of CD25(+) naTregs strongly enhances the frequency of IL-4-producing effector T cells in acute egg-induced inflammation. It does not change clonal expansion of activated CD4(+) T cells. This regulation of egg-induced cytokine production does not require the presence of IL-10. These data demonstrate that naTregs limit egg-induced effector-cytokine production in our model. Our results identify naTregs as an important, IL-10-independent part of the regulatory network in schistosome egg-induced inflammation.  相似文献   
143.
ImmobilizedCandida antarctica lipase was used to catalyze the separation of ketoprofen into its components by means of esterification followed by the enzymatic hydrolysis of the ester product. In this study, ketoprofen underwent esterification to ethanol in the presence of isooctane. When the reaction was complete, 58.3% of the ketoprofen had been transformed into an ester. The ketoprofen remaining in solution after the reation was complete consisted primarily of itsS-enantiomer (83.0%), while the 59.4% of the ketoprofen component of the ester consisted of itsR-enantiomer. We then subjected the ester product to enzymatic hydrolysis in the presence of the same enzyme and produced a ketoprofen product rich in theR-enantiomer; 77% of this product consisted of theR-enantiomer when 50% of the ester had been hydrolyzed, and 90% of it consisted of theR-enantiomer when 30% of the ester had been hydrolyzed. By contrast, theR-enantiomer levels only reached approximately 42 and 65%, respectively, when 50 and 30% of the racemic ester was hydrolyzed under the same conditions.  相似文献   
144.
A study of the stable isotope composition (δ18O, δ13C) of biogenic (ostracod, mollusc) and authigenic carbonates in the Ballagan Formation, Lower Carboniferous of Scotland, coupled with evidence from sedimentology and associated fossil fauna and flora, supports the argument that this formation was deposited in a coastal flood plain setting, in brackish (0.5 < 30‰ NaCl) and hypersaline (> 40‰ NaCl) waters, but in the absence of persistent normal marine conditions. The oxygen isotope data from the Ballagan Formation divide into three clusters: a diagenetic field defined by low δ18O (< − 11‰ VPDB); an intermediary field (δ18O − 11‰ to − 9‰) composed of a mixture of known primary and secondary (diagenetic) carbonates; and samples within the range of − 9‰ to − 4‰ which, as far as we can ascertain, are largely unaltered. No samples give typical Early Carboniferous δ18O marine values. Average marine carbonates from Europe have δ18O between − 4‰ to − 3‰. The Ballagan Formation carbonates were probably deposited in evaporated freshwater and/or brackish water. This conclusion is supported by the presence of evaporites (gypsum, anhydrite, halite pseudomorphs) and common desiccation-cracked mudstone surfaces throughout the Ballagan Formation, suggesting conditions of fluctuating salinity in ephemeral bodies of water. The stable isotope data support the notion that the ostracod assemblages of the Ballagan Formation were colonising brackish water and hypersaline ecologies on a coastal flood plain during the Early Carboniferous, a stage of development that may have encouraged their colonisation of fully non-marine (limnetic) environments during the later Carboniferous. The ostracods include cytherellacean and kloedenellacean species known from marginal marine sites elsewhere, but probably tolerant of brackish water, podocopid species such as ‘Bythocyprisaequalis that may have been adapted for brackish water settings on coastal flood plains (ephemeral lakes and lagoons), and paraparchitacean-dominated assemblages that may signal harsh (hypersaline or desiccating) environments.  相似文献   
145.
Zhou C  Leng B  Yao J  Qian J  Chen X  Zhou P  Knight DP  Shao Z 《Biomacromolecules》2006,7(8):2415-2419
Spider dragline silk with its superlative tensile properties provides an ideal system to study the relationship between morphology and mechanical properties of a structural protein. Accordingly, we synthesized two hybrid multiblock copolymers by condensing poly(alanine) [(Ala)(5)] blocks of the structural proteins (spidroin MaSp1 and MaSp2) of spider dragline silk with different oligomers of isoprene (2200 and 5000 Da) having reactive end groups. The synthetic multiblock polymer displayed similar secondary structure to that of natural spidroin, the peptide segment forming a beta-sheet structure. These multiblock polymers showed a significant solubility in the component solvents. Moreover, the copolymer which contains the short polyisoprene segment would aggregate into a micellar-like structure, as observed by TEM.  相似文献   
146.
147.
Cell migration plays major roles in human breast cancer-related death, but the molecular mechanisms remain unclear. Valproic acid (VPA) is a broad-spectrum inhibitor of class I and II histone deacetylases and shows great anticancer activity in a variety of human cancers including breast cancer. In this study, we found that VPA significantly inhibited cell migration but not proliferation of human breast cancer MDA-MB-231 cells. Mechanistic studies found that VPA significantly inhibited the expression of Survivin. Knockdown of Survivin could obviously inhibited cell migration, while over-expression of Survivin markedly rescued the inhibition of VPA on cell migration. Further studies found that knockdown of HDAC2 completely mimicked the effects of VPA on Survivin and cell migration, and over-expression of Survivin could also rescue the effects of HDAC2 knockdown on cell migration. Collectively, these results indicated that HDAC2 may be the specific target of VPA in breast cancer cells, and specific inhibition of HDAC2, especially by small molecular chemicals may lead to less side-effects and provide a better strategy than VPA application for human breast cancer treatment.  相似文献   
148.
The interleukin 23 receptor (IL-23R) polymorphisms have been already discussed in rheumatoid arthritis (RA) repeatedly, but the results are conflict. The purpose of this meta-analysis was to assess whether IL-23R gene polymorphisms are associated with RA. We retrieved the available data from Pubmed, Medline, CNKI and CBM. Our study evaluated the effects of two polymorphisms (rs10489629, rs7517847) in European population. Pooling all the subjects, we found significant associations between the two polymorphisms and RA. For rs10489629, the pooled ORs (95 % CI) of C versus T, C/C+C/T versus T/T and C/C versus C/T+T/T were 1.092 (1.038-1.149), 1.146 (1.059-1.240) and 1.099 (1.008-1.199), respectively. For rs7517847, the combined ORs (95 % CI) of G versus T, G/G+G/T versus T/T and G/G versus G/T+T/T were 1.121 (1.063-1.183), 1.184 (1.092-1.283) and 1.133 (1.030-1.246), respectively. In conclusion, this meta-analysis demonstrates that the polymorphisms rs10489629 and rs7517847 of the IL-23R gene may be considered as risk factors for developing RA in European population.  相似文献   
149.
Cao H  Leng X  Li C  Wei Q  Gui J  Cheng H  Zhou R 《Molecular biology reports》2012,39(4):4647-4653
Chinese sturgeon (Acipenser sinensis) is a rare and endangered species and also an important resource for the sturgeon aquaculture industry, however, a few genes have been identified in this species. We report here construction of a pituitary cDNA library from a 24 years old female Chinese sturgeon just after its spawning, and obtained 2,025 ESTs from the library. 885 unique sequences were identified, which were categorized into 12 functional groups. More than half of the unique sequences (57%) do not match with annotated sequences in the public databases. Three of these novel genes were further identified. Notably, a full-length of cDNA (1,143 bp) encoding somatolactin of 232 amino acids was identified. Phylogenetic analysis showed 97% amino acid identity with White sturgeon somatolactin. RT-PCR analysis indicated that the somatolactin mRNA was only detected in pituitary. Pituitary-specific expression of the somatolactin suggested that the protein may play important physiological functions in pituitary-endocrine system of the Chinese sturgeon.  相似文献   
150.
The rumen content of four Yunnan Yellow Cattle (Bos taurs) were collected to determine the bacteria diversity by using 16S rRNA gene sequence analysis. A total of 129 sequences were examined and the sequences were referred as 107 OTU (Operational Taxonomy Unit) according to the similarity level of 97% in gene sequence. Similarity analysis revealed that Yunnan Yellow Cattle had 12 sequences (10 OTU) shared 97% or greater similarity with cultured rumen bacteria Butyrivibrio fibrisolvens, Succiniclasticum ruminis, Ruminococcus bromii, Clostridium proteoclasticum, Ruminococcus flavefaciens, Pseudobutyrivibrio ruminis, Jeotgalicoccus psychrophilus, and Prevotella ruminicola, which accounting for 9.3% of the total clones (9.2% of the total OTU). The further 12 sequences (9 OTU) shared 90–97% similarity with cultured bacteria Clostridium aminobutyricum, butyrate-producing bacterium, Schwartzia succinivorans, Prevotella ruminicola, Eubacterium ruminantium, Ruminococcus albus, and Clostridium termitidis, also accounting for 9.3% of the total sequences (8.3% of the total OTU). The remaining 105 sequences (90 OTU) shared less than 90% similarity with cultured bacteria, accounting for 81.4% of the total sequences (82.5% of the total OTU). According to the phylogenetic analysis, all sequences were phylogenetically placed within phyla of low G+C subdivision (accounting for 72.1 and 72.5% of the total clones and OTU, respectively) and CFB subdivision (Cytophaga-Flexibacter-Bacteroides; accounting for 27.9 and 27.5% of the total clones and OTU, respectively). Among the examined clones, rare bacteria Jeotgalicoccus psychrophilus was detected in the rumen of cattle.  相似文献   
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