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51.
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Paszkowski U 《Current opinion in plant biology》2006,9(4):364-370
Plants are solar-powered sugar factories that feed a multitude of other organisms. Many of these organisms associate directly with host plants to gain access to the plant's photosynthates. Such symbioses encompass a wide collection of styles ranging from mutualistic to commensal and parasitic. Among these, the mutualistic arbuscular mycorrhizal (AM) symbiosis is one of the evolutionarily oldest symbioses of plants, relying on the formation of an intimate relationship between fungi of the Glomeromycota and roots of the majority of vascular flowering plants. In this symbiosis, the fungus intracellularly colonizes living root cells, implying the existence of an extreme form of compatibility. Interestingly, molecular events that happen in the plant in response to mycorrhizal colonization also occur in other beneficial and, as recently shown, even antagonistic plant symbioses. Thus, basic 'compatibility modules' appear to be partially conserved between mutualism and parasitism. 相似文献
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Jorge Esparza-Gordillo Anja Matanovic Ingo Marenholz Anja Bauerfeind Klaus Rohde Katja Nemat Min-Ae Lee-Kirsch Magnus Nordenskj?ld Marten C. G. Winge Thomas Keil Renate Krüger Susanne Lau Kirsten Beyer Birgit Kalb Bodo Niggemann Norbert Hübner Heather J. Cordell Maria Bradley Young-Ae Lee 《PLoS genetics》2015,11(3)
Epidemiological studies suggest that allergy risk is preferentially transmitted through mothers. This can be due to genomic imprinting, where the phenotype effect of an allele depends on its parental origin, or due to maternal effects reflecting the maternal genome''s influence on the child during prenatal development. Loss-of-function mutations in the filaggrin gene (FLG) cause skin barrier deficiency and strongly predispose to atopic dermatitis (AD). We investigated the 4 most prevalent European FLG mutations (c.2282del4, p.R501X, p.R2447X, and p.S3247X) in two samples including 759 and 450 AD families. We used the multinomial and maximum-likelihood approach implemented in the PREMIM/EMIM tool to model parent-of-origin effects. Beyond the known role of FLG inheritance in AD (R1meta-analysis = 2.4, P = 1.0 x 10−36), we observed a strong maternal FLG genotype effect that was consistent in both independent family sets and for all 4 mutations analysed. Overall, children of FLG-carrier mothers had a 1.5-fold increased AD risk (S1 = 1.50, Pmeta-analysis = 8.4 x 10−8). Our data point to two independent and additive effects of FLG mutations: i) carrying a mutation and ii) having a mutation carrier mother. The maternal genotype effect was independent of mutation inheritance and can be seen as a non-genetic transmission of a genetic effect. The FLG maternal effect was observed only when mothers had allergic sensitization (elevated allergen-specific IgE antibody plasma levels), suggesting that FLG mutation-induced systemic immune responses in the mother may influence AD risk in the child. Notably, the maternal effect reported here was stronger than most common genetic risk factors for AD recently identified through genome-wide association studies (GWAS). Our study highlights the power of family-based studies in the identification of new etiological mechanisms and reveals, for the first time, a direct influence of the maternal genotype on the offspring’s susceptibility to a common human disease. 相似文献
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Pseudomonas aeruginosa is the causative agent of chronic respiratory infections and is an important pathogen of cystic fibrosis patients. Adaptive mutations play an essential role for antimicrobial resistance and persistence. The factors that contribute to bacterial mutagenesis in this environment are not clear. Recently it has been proposed that cationic antimicrobial peptides such as LL-37 could act as mutagens in P. aeruginosa. Here we provide experimental evidence that mutagenesis is the product of a joint action of LL-37 and free iron. By estimating mutation rate, mutant frequencies and assessing mutational spectra in P. aeruginosa treated either with LL-37, iron or a combination of both we demonstrate that mutation rate and mutant frequency were increased only when free iron and LL-37 were present simultaneously. Colistin had the same effect. The addition of an iron chelator completely abolished this mutagenic effect, suggesting that LL-37 enables iron to enter the cells resulting in DNA damage by Fenton reactions. This was also supported by the observation that the mutational spectrum of the bacteria under LL-37-iron regime showed one of the characteristic Fenton reaction fingerprints: C to T transitions. Free iron concentration in nature and within hosts is kept at a very low level, but the situation in infected lungs of cystic fibrosis patients is different. Intermittent bleeding and damage to the epithelial cells in lungs may contribute to the release of free iron that in turn leads to generation of reactive oxygen species and deterioration of the respiratory tract, making it more susceptible to the infection. 相似文献
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Christian Schwager Skadi Kull Susanne Krause Frauke Schocker Arnd Petersen Wolf-Meinhard Becker Uta Jappe 《PloS one》2015,10(4)
Background
Peanut allergy is one of the most severe class I food allergies with increasing prevalence. Especially lipophilic allergens, such as oleosins, were found to be associated with severe symptoms, but are usually underrepresented in diagnostic extracts. Therefore, this study focused on isolation, molecular characterization and assessment of the allergenicity of peanut oleosins.Methods and Results
A comprehensive method adapted for the isolation of peanut oil bodies of high purity was developed comprising a stepwise removal of seed storage proteins from oil bodies. Further separation of the oil body constituents, including the allergens Ara h 10, Ara h 11, the presumed allergen oleosin 3 and additional oleosin variants was achieved by a single run on a preparative electrophoresis cell. Protein identification realized by N-terminal sequencing, peptide mass fingerprinting and homology search revealed the presence of oleosins, steroleosins and a caleosin. Immunoblot analysis with sera of peanut-allergic individuals illustrated the IgE-binding capacity of peanut-derived oleosins.Conclusion
Our method is a novel way to isolate all known immunologically distinct peanut oleosins simultaneously. Moreover, we were able to provide evidence for the allergenicity of oleosins and thus identified peanut oleosins as probable candidates for component-resolved allergy diagnosis. 相似文献60.
Max Ernst Bender Suzanne Edwards Peter von Philipsborn Fridolin Steinbeis Thomas Keil Peter Tinnemann 《PLoS neglected tropical diseases》2015,9(12)