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1.
Mass culture of benthic macroalgae under rough offshore conditions in the North Sea requires rigid culture support systems that cannot only withstand rough weather conditions but can also be effectively handled while at the same time retain the cultured species. Various carrier constructions and different mooring systems were tested. Laminaria saccharina grew on all of these carriers with initially high (up to 14.5% per day) and later decreasing length increments. Longlines, ladder and grid systems had certain disadvantages and these are discussed. The study results led to a new ring carrier (patent pending), first used in 1994/1995, which was gradually improved until 2002. This system now emerges as being superior, since it resists not only rough weather conditions (2 m s–1 current velocity, 6 m wave height) but also permits ease of handling when compared to other constructions. The ring allows various operational modes and can be equipped with culture lines that can be collected offshore or transported to shore facilities for harvesting. The modular nature of the tested ring system lends itself for future use in integrated aquaculture systems located in or attached to offshore wind farms. 相似文献
2.
Cornelia Franz 《International journal of primatology》1999,20(4):525-546
I tested the utility of Seyfarth's (1977) model of rank-related attractiveness to explain the distribution of allogrooming behavior among captive bonobos (Pan paniscus). Adult female bonobos generally have high social status and may be dominant over males. As predicted by the model, I found that high-ranking adult females received most allogrooming within each of the four investigated groups. Among adult female-adult female dyads, however, allogrooming was not clearly associated with dominance rank. Contradictory to predictions of the model, the highest-ranking females were responsible for most displacements over allogrooming, and grooming competition is positively correlated with dominance rank. In the second part of this study, I investigated the social significance of allogrooming body site preferences. Bonobos direct significantly most allogrooming to the face of conspecifics, and high- and low-ranking individuals, as well as males and females, differ significantly in their preferences for certain allogrooming sites. Subordinates and males tended to avoid facial grooming and preferred the back and anogenital region, while high-ranking individuals and females directed most allogrooming to the face and head of grooming partners. Data from this study support the hypothesis that high-ranking females are the most attractive grooming partners within a female-centered bonobo society. Many other aspects of allogrooming behavior, however, are not consistent with the model of rank-related attractiveness. 相似文献
3.
Wolschek M Samm E Seper H Sturlan S Kuznetsova I Schwager C Khassidov A Kittel C Muster T Egorov A Bergmann M 《Journal of virology》2011,85(5):2469-2473
Segment 8 of the influenza A virus codes for two proteins (NS1 and NS2/NEP) via splicing. Here, we developed a viral vector expressing a cytokine or chemokine instead of the interferon antagonist NS1. To achieve both the desired genetic stability and high transgene expression levels, NS2/NEP mRNA splicing efficacy had to be fine-tuned by modification of splicing elements. Expression levels of secreted foreign proteins could be further enhanced by fusing the N-terminal 13 amino acids of NS1 with an IgK-derived secretion signal peptide. Thus, the first start codon was used for translation initiation of both NS2/NEP and the foreign protein. 相似文献
4.
The effects of four plant extract formulations on the orientation and survival of subterranean termites were tested. In choice experiments, extract-treated filter paper had a significantly repellent effect on groups of Reticulitermes santonensis De Feytaud, R. virginicus (Banks), Coptotermes formosanus Shiraki, and Schedorhinotermes intermedius Breinli. There was no species-specific difference in avoidance behavior toward the tested concentrations. No-choice experiments revealed toxic properties of all investigated extracts by contact or airborne compounds against R. santonensis. However, high termite mortality was only achieved by forced direct or forced indirect exposure to the plant material, Feeding deterrence or digestive toxicity could not be judged in these experiments. One of the extracts was efficiently used for soil treatments to protect a food substrate against R. santonenis infestation. Extract-treated barriers in the experiments did not affect mortality compared with control trials but prevented termites from penetrating treated soil. 相似文献
5.
Oliver Poetz Tanja Henzler Michael Hartmann Cornelia Kazmaier Markus F. Templin Thomas Herget Thomas O. Joos 《Molecular & cellular proteomics : MCP》2010,9(11):2474-2481
Microarray-based sandwich immunoassays can simultaneously detect dozens of proteins. However, their use in quantifying large numbers of proteins is hampered by cross-reactivity and incompatibilities caused by the immunoassays themselves. Sequential multiplex analyte capturing addresses these problems by repeatedly probing the same sample with different sets of antibody-coated, magnetic suspension bead arrays. As a miniaturized immunoassay format, suspension bead array-based assays fulfill the criteria of the ambient analyte theory, and our experiments reveal that the analyte concentrations are not significantly changed. The value of sequential multiplex analyte capturing was demonstrated by probing tumor cell line lysates for the abundance of seven different receptor tyrosine kinases and their degree of phosphorylation and by measuring the complex phosphorylation pattern of the epidermal growth factor receptor in the same sample from the same cavity.Phosphorylation of proteins is an integral part of the signal transduction of eukaryotic cells as it modulates the activity of complex protein networks. Although Western blot- and immunoprecipitation-based MS approaches (1, 2) can lead to detailed insights into these processes, most of the integrated approaches only allow a static view of protein phosphorylation because they are not suitable for the screening of hundreds of samples. Either planar or bead array-based sandwich immunoassays can be used to analyze the quantity and activation state of signaling molecules in multiplex, enabling the systematic profiling of protein abundance and post-translational modifications (3–6) in hundreds of samples. However, multiplex immunoassays are only suitable for the simultaneous analysis of a limited number of proteins. The detection of comprehensive phosphorylation patterns is difficult as this involves assay systems that are incompatible with multiplexing.In principle, two sandwich immunoassay setups are possible for probing the phosphorylation state of a protein. The first setup applies a capture antibody specific for a non-modified part of the protein and uses a phosphorylation state-specific detection antibody. When applied to an array-based format, however, this setup does not allow for the simultaneous measurement of the abundance and the degree of phosphorylation (3, 4). A mixture of detection antibodies, one specific for the phosphorylation site and one specific for the non-modified site of the protein, would bind simultaneously to the two different epitopes, and assay signals could not be further deconvoluted by the spatial or color code of the array. The second sandwich immunoassay setup for the analysis of protein phosphorylation applies a phosphorylation state-specific capture antibody and a protein-specific detection antibody. In such a setup, an anti-phosphotyrosine antibody (e.g. mAb 4G10) cannot be applied as a capture antibody because a huge variety of tyrosine phosphorylated proteins would be captured, and specific signals could rarely be deconvoluted. Using capture antibodies that bind to phosphorylated epitopes in the context of their flanking amino acids is not a problem until a multiplex readout is desired. If one antibody specific for the phosphosite and one antibody specific for the abundance of a protein are used together in a multiplex assay panel they might compete for their analyte. The situation becomes even more complex if the protein of interest contains various phosphorylation sites such as e.g. the epidermal growth factor receptor. Several capture antibodies target different epitopes of the same protein and therefore compete for the overall amount of targeted protein in the sample, thus making a valid simultaneous measurement problematic.Although different ways of tackling the problem of assay multiplexing are in use, we demonstrated the feasibility to sequentially perform such incompatible assays from the same sample using a magnetic particle handler that moves particles through the samples and reagents (Fig. 1). Using a model assay, we confirmed that suspension bead array-based immunoassays work under ambient analyte conditions. As described by Roger Ekins (7), decreasing of the amount of capture antibody in a sandwich immunoassay setup from a macrospot (e.g. a microtiter plate assay) to a microspot generates a scenario where only a tiny fraction of the present target analytes is captured on the microspot. Therefore, the overall concentration of the analyte molecules in the sample does not change significantly even in the case of low target concentrations and high affinity binding reactions. Furthermore, as the initial concentration of the analyte is not significantly changed when performing a miniaturized sandwich immunoassay, multiple post-translational modifications within the same protein can be measured either in sequence or in parallel in the same multiplex panel.Open in a separate windowFig. 1.Sequential multiplex analyte capturing. Magnetic suspension bead array assays can be performed sequentially, reusing the same sample material (indicated by the blue arrow). The use of a magnetic particle handler enables the quantitative transfer (black arrow) of the magnetic beads from the sample well into the wells containing washing solutions or other assay reagents. Magnetic beads from the first bead array panel are incubated with the samples to capture their respective analyte. Then the magnetic beads are subjected to washing and detection steps and are finally transferred into the readout plate (first row). After retracting the magnetic suspension bead array of the first assay panel from the sample, a bead array from the second assay panel is added and processed as described above but using different detection antibodies (second row). A third bead array assay panel can be applied after removing the second panel (third row) and so on.By probing tumor cell lines for the abundance of seven different receptor tyrosine kinases and their generic tyrosine phosphorylation, we generated complex phosphorylation patterns and thereby demonstrated the potential of this approach. More importantly, demonstrating ambient analyte conditions allowed the parallel detection of phosphorylation at different sites of the EGFR1 using phosphorylation site-specific antibodies as capture molecules with one assay panel. Phosphorylation of eight different sites and the abundance of the EGFR could be quantified relative to one another without any interference of the different immunoassays during multiplexing because competition for the analyte can be prevented by running the assays under ambient analyte conditions. 相似文献
6.
Preethi Vijayaraj Cornelia Kr?ger Ursula Reuter Reinhard Windoffer Rudolf E. Leube Thomas M. Magin 《The Journal of cell biology》2009,187(2):175-184
Keratin intermediate filament proteins form cytoskeletal scaffolds in epithelia, the disruption of which affects cytoarchitecture, cell growth, survival, and organelle transport. However, owing to redundancy, the global function of keratins has not been defined in full. Using a targeted gene deletion strategy, we generated transgenic mice lacking the entire keratin multiprotein family. In this study, we report that without keratins, embryonic epithelia suffer no cytolysis and maintain apical polarity but display mislocalized desmosomes. All keratin-null embryos die from severe growth retardation at embryonic day 9.5. We find that GLUT1 and -3 are mislocalized from the apical plasma membrane in embryonic epithelia, which subsequently activates the energy sensor adenosine monophosphate kinase (AMPK). Analysis of the mammalian target of rapamycin (mTOR) pathway reveals that AMPK induction activates Raptor, repressing protein biosynthesis through mTORC1''s downstream targets S6 kinase and 4E-binding protein 1. Our findings demonstrate a novel keratin function upstream of mTOR signaling via GLUT localization and have implications for pathomechanisms and therapy approaches for keratin disorders and the analysis of other gene families. 相似文献
7.
Most songbirds learn their songs from adult tutors, who can be their father or other male conspecifics. However, the variables that control song learning in a natural social context are largely unknown. We investigated whether the time of hatching of male domesticated canaries has an impact on their song development and on the neuroendocrine parameters of the song control system. Average age difference between early- and late-hatched males was 50 days with a maximum of 90 days. Song activity of adult tutor males decreased significantly during the breeding season. While early-hatched males were exposed to tutor songs for on average the first 99 days, late-hatched peers heard adult song only during the first 48 days of life. Remarkably, although hatching late in the season negatively affected body condition, no differences between both groups of males were found in song characteristics either in autumn or in the following spring. Similarly, hatching date had no effect on song nucleus size and circulating testosterone levels. Our data suggest that late-hatched males must have undergone accelerated song development. Furthermore, the limited tutor song exposure did not affect adult song organization and song performance. 相似文献
8.
Ohne Zusammenfassung 相似文献
9.
10.
Cornelia A. M. van de Weg Ralph M. H. G. Huits Cláudio S. Pannuti Rosalba M. Brouns Riemsdijk W. A. van den Berg Henk-Jan van den Ham Byron E. E. Martina Albert D. M. E. Osterhaus Mihai G. Netea Joost C. M. Meijers Eric C. M. van Gorp Esper G. Kallas 《PLoS neglected tropical diseases》2014,8(10)