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961.
Outi Vaarala Arja Vuorela Markku Partinen Marc Baumann Tobias L. Freitag Seppo Meri P?ivi Saavalainen Matti Jauhiainen Rabah Soliymani Turkka Kirjavainen P?ivi Olsen Outi Saarenp??-Heikkil? Juha Rouvinen Merja Roivainen Hanna Nohynek Jukka Jokinen Ilkka Julkunen Terhi Kilpi 《PloS one》2014,9(12)
Background
Narcolepsy results from immune-mediated destruction of hypocretin secreting neurons in hypothalamus, however the triggers and disease mechanisms are poorly understood. Vaccine-attributable risk of narcolepsy reported so far with the AS03 adjuvanted H1N1 vaccination Pandemrix has been manifold compared to the AS03 adjuvanted Arepanrix, which contained differently produced H1N1 viral antigen preparation. Hence, antigenic differences and antibody response to these vaccines were investigated.Methods and Findings
Increased circulating IgG-antibody levels to Pandemrix H1N1 antigen were found in 47 children with Pandemrix-associated narcolepsy when compared to 57 healthy children vaccinated with Pandemrix. H1N1 antigen of Arepanrix inhibited poorly these antibodies indicating antigenic difference between Arepanrix and Pandemrix. High-resolution gel electrophoresis quantitation and mass spectrometry identification analyses revealed higher amounts of structurally altered viral nucleoprotein (NP) in Pandemrix. Increased antibody levels to hemagglutinin (HA) and NP, particularly to detergent treated NP, was seen in narcolepsy. Higher levels of antibodies to NP were found in children with DQB1*06∶02 risk allele and in DQB1*06∶02 transgenic mice immunized with Pandemrix when compared to controls.Conclusions
This work identified 1) higher amounts of structurally altered viral NP in Pandemrix than in Arepanrix, 2) detergent-induced antigenic changes of viral NP, that are recognized by antibodies from children with narcolepsy, and 3) increased antibody response to NP in association of DQB1*06∶02 risk allele of narcolepsy. These findings provide a link between Pandemrix and narcolepsy. Although detailed mechanisms of Pandemrix in narcolepsy remain elusive, our results move the focus from adjuvant(s) onto the H1N1 viral proteins. 相似文献962.
The cheap and easy identification of species is necessary within multiple fields of molecular biology. The use of high-resolution melting (HRM) of DNA provides a fast closed-tube method for analysis of the sequence composition of the mitochondrial genes 12S rRNA and cytochrome b. We investigated the potential use of HRM for species identification within eleven different animal groups commonly found in Europe by animal-group-specific DNA amplification followed by DNA melting. Influence factors as DNA amount, additional single base alterations, and the existence of mixed samples were taken into consideration. Visual inspection combined with mathematical evaluation of the curve shapes did resolve nearly all species within an animal group. The assay can therefore not only be used for identification of animal groups and mixture analysis but also for species identification within the respective groups. The use of a universal 12S rRNA system additionally revealed a possible approach for species discrimination, mostly by exclusion. The use of the HRM assay showed to be a reliable, fast, and cheap method for species discrimination within a broad range of different animal species and can be used in a flexible “modular” manner depending on the question to be solved. 相似文献
963.
Miriam Ehrnthaler Lars B. Scharff Tobias T. Fleischmann Claudia Hasse Stephanie Ruf Ralph Bock 《The Plant cell》2014,26(2):765-776
Consistent with their origin from cyanobacteria, plastids (chloroplasts) perform
protein biosynthesis on bacterial-type 70S ribosomes. The plastid genomes of seed
plants contain a conserved set of ribosomal protein genes. Three of these have proven
to be nonessential for translation and, thus, for cellular viability:
rps15, rpl33, and rpl36. To
help define the minimum ribosome, here, we examined whether more than one of these
nonessential plastid ribosomal proteins can be removed from the 70S ribosome. To that
end, we constructed all possible double knockouts for the S15, L33, and L36 ribosomal
proteins by stable transformation of the tobacco (Nicotiana tabacum)
plastid genome. We find that, although S15 and L33 function in different ribosomal
particles (30S and 50S, respectively), their combined deletion from the plastid
genome results in synthetic lethality under autotrophic conditions. Interestingly,
the lethality can be overcome by growth under elevated temperatures due to an
improved efficiency of plastid ribosome biogenesis. Our results reveal functional
interactions between protein and RNA components of the 70S ribosome and uncover the
interdependence of the biogenesis of the two ribosomal subunits. In addition, our
findings suggest that defining a minimal set of plastid genes may prove more complex
than generally believed. 相似文献
964.
Tobias Maierhofer Christof Lind Stefanie Hüttl S?nke Scherzer Melanie Papenfu? Judy Simon Khaled A.S. Al-Rasheid Peter Ache Heinz Rennenberg Rainer Hedrich Thomas D. Müller Dietmar Geiger 《The Plant cell》2014,26(6):2554-2567
In contrast to animal cells, plants use nitrate as a major source of nitrogen.
Following the uptake of nitrate, this major macronutrient is fed into the vasculature
for long-distance transport. The Arabidopsis thaliana shoot
expresses the anion channel SLOW ANION CHANNEL1 (SLAC1) and its homolog SLAC1
HOMOLOGOUS3 (SLAH3), which prefer nitrate as substrate but cannot exclude chloride
ions. By contrast, we identified SLAH2 as a nitrate-specific channel that is
impermeable for chloride. To understand the molecular basis for nitrate selection in
the SLAH2 channel, SLAC1 and SLAH2 were modeled to the structure of HiTehA, a
distantly related bacterial member. Structure-guided site-directed mutations
converted SLAC1 into a SLAH2-like nitrate-specific anion channel and vice versa. Our
findings indicate that two pore-occluding phenylalanines constrict the pore. The
selectivity filter of SLAC/SLAH anion channels is determined by the polarity of
pore-lining residues located on alpha helix 3. Changing the polar character of a
single amino acid side chain (Ser-228) to a nonpolar residue turned the
nitrate-selective SLAH2 into a chloride/nitrate-permeable anion channel. Thus, the
molecular basis of the anion specificity of SLAC/SLAH anion channels seems to be
determined by the presence and constellation of polar side chains that act in concert
with the two pore-occluding phenylalanines. 相似文献
965.
Florian Fr?hlich Romain Christiano Daniel K. Olson Abel Alcazar-Roman Pietro DeCamilli Tobias C. Walther 《Molecular biology of the cell》2014,25(18):2797-2806
The plasma membrane delineates the cell and mediates its communication and material exchange with the environment. Many processes of the plasma membrane occur through interactions of proteins with phosphatidylinositol(4,5)-bisphosphate (PI(4,5)P2), which is highly enriched in this membrane and is a key determinant of its identity. Eisosomes function in lateral organization of the plasma membrane, but the molecular function of their major protein subunits, the BAR domain–containing proteins Pil1 and Lsp1, is poorly understood. Here we show that eisosomes interact with the PI(4,5)P2 phosphatase Inp51/Sjl1, thereby recruiting it to the plasma membrane. Pil1 is essential for plasma membrane localization and function of Inp51 but not for the homologous phosphatidylinositol bisphosphate phosphatases Inp52/Sjl2 and Inp53/Sjl3. Consistent with this, absence of Pil1 increases total and available PI(4,5)P2 levels at the plasma membrane. On the basis of these findings, we propose a model in which the eisosomes function in maintaining PI(4,5)P2 levels by Inp51/Sjl1 recruitment. 相似文献
966.
967.
Katharina V. Alheit Lucas Busemeyer Wenxin Liu Hans Peter Maurer Manje Gowda Volker Hahn Sigrid Weissmann Arno Ruckelshausen Jochen C. Reif Tobias Würschum 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(1):251-260
Key message
QTL mapping in multiple families identifies trait-specific and pleiotropic QTL for biomass yield and plant height in triticale.Abstract
Triticale shows a broad genetic variation for biomass yield which is of interest for a range of purposes, including bioenergy. Plant height is a major contributor to biomass yield and in this study, we investigated the genetic architecture underlying biomass yield and plant height by multiple-line cross QTL mapping. We employed 647 doubled haploid lines from four mapping populations that have been evaluated in four environments and genotyped with 1710 DArT markers. Twelve QTL were identified for plant height and nine for biomass yield which cross-validated explained 59.6 and 38.2 % of the genotypic variance, respectively. A major QTL for both traits was identified on chromosome 5R which likely corresponds to the dominant dwarfing gene Ddw1. In addition, we detected epistatic QTL for plant height and biomass yield which, however, contributed only little to the genetic architecture of the traits. In conclusion, our results demonstrate the potential of genomic approaches for a knowledge-based improvement of biomass yield in triticale. 相似文献968.
María Flor García-Mayoral Miguel Angel Trevi?o Teresa Pérez-Pi?ar María Luisa Caballero Tobias Knaute Ana Umpierrez Marta Bruix Rosa Rodríguez-Pérez 《PLoS neglected tropical diseases》2014,8(3)
Background
Anisakiasis is a re-emerging global disease caused by consumption of raw or lightly cooked fish contaminated with L3 Anisakis larvae. This zoonotic disease is characterized by severe gastrointestinal and/or allergic symptoms which may misdiagnosed as appendicitis, gastric ulcer or other food allergies.The Anisakis allergen Ani s 5 is a protein belonging to the SXP/RAL-2 family; it is detected exclusively in nematodes. Previous studies showed that SXP/RAL-2 proteins are active antigens; however, their structure and function remain unknown.The aim of this study was to elucidate the three-dimensional structure of Ani s 5 and its main IgE and IgG4 binding regions.Methodology/Principal Findings
The tertiary structure of recombinant Ani s 5 in solution was solved by nuclear magnetic resonance. Mg2+, but not Ca2+, binding was determined by band shift using SDS-PAGE. IgE and IgG4 epitopes were elucidated by microarray immunoassay and SPOTs membranes using sera from nine Anisakis allergic patients.The tertiary structure of Ani s 5 is composed of six alpha helices (H), with a Calmodulin like fold. H3 is a long, central helix that organizes the structure, with H1 and H2 packing at its N-terminus and H4 and H5 packing at its C-terminus. The orientation of H6 is undefined. Regarding epitopes recognized by IgE and IgG4 immunoglobulins, the same eleven peptides derived from Ani s 5 were bound by both IgE and IgG4. Peptides 14 (L40-K59), 26 (A76-A95) and 35 (I103-D122) were recognized by three out of nine sera.Conclusions/Significance
This is the first reported 3D structure of an Anisakis allergen. Magnesium ion binding and structural resemblance to Calmodulin, suggest some putative functions for SXP/RAL-2 proteins. Furthermore, the IgE/IgG4 binding regions of Ani s 5 were identified as segments localized on its surface. These data will contribute towards a better understanding of the interactions that occur between immunoglobulins and allergens and, in turn, facilitate the design of novel diagnostic tests and immunotherapeutic strategies. 相似文献969.
Nana Ama Amissah Sophie Gryseels Nicholas J. Tobias Bahram Ravadgar Mitsuko Suzuki Koen Vandelannoote Lies Durnez Herwig Leirs Timothy P. Stinear Fran?oise Portaels Anthony Ablordey Miriam Eddyani 《PLoS neglected tropical diseases》2014,8(9)
Background
The reservoir and mode of transmission of Mycobacterium ulcerans, the causative agent of Buruli ulcer, still remain a mystery. It has been suggested that M. ulcerans persists with difficulty as a free-living organism due to its natural fragility and inability to withstand exposure to direct sunlight, and thus probably persists within a protective host environment.Methodology/Principal Findings
We investigated the role of free-living amoebae as a reservoir of M. ulcerans by screening the bacterium in free-living amoebae (FLA) cultures isolated from environmental specimens using real-time PCR. We also followed the survival of M. ulcerans expressing green fluorescence protein (GFP) in Acanthameoba castellanii by flow cytometry and observed the infected cells using confocal and transmission electron microscopy for four weeks in vitro. IS2404 was detected by quantitative PCR in 4.64% of FLA cultures isolated from water, biofilms, detritus and aerosols. While we could not isolate M. ulcerans, 23 other species of mycobacteria were cultivated from inside FLA and/or other phagocytic microorganisms. Laboratory experiments with GFP-expressing M. ulcerans in A. castellani trophozoites for 28 days indicated the bacteria did not replicate inside amoebae, but they could remain viable at low levels in cysts. Transmission electron microscopy of infected A. castellani confirmed the presence of bacteria within both trophozoite vacuoles and cysts. There was no correlation of BU notification rate with detection of the IS2404 in FLA (r = 0.07, n = 539, p = 0.127).Conclusion/Significance
This study shows that FLA in the environment are positive for the M. ulcerans insertion sequence IS2404. However, the detection frequency and signal strength of IS2404 positive amoabae was low and no link with the occurrence of BU was observed. We conclude that FLA may host M. ulcerans at low levels in the environment without being directly involved in the transmission to humans. 相似文献970.