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1.
A synthetic chimeric gene, TBI-HBS, encoding the immunogenic ENV and GAG epitopes of human immunodeficiency virus (HIV-1) and the surface protein antigen (HBsAg) of hepatitis B virus (HBV), was expressed in tomato plants. Tomato fruits containing the TBI-HBS antigen were fed to experimental mice and, on days 14 and 28 post-feeding, high levels of HIV- and HBV-specific antibodies were present in the serum and feces of the test animals. Intraperitoneal injection of a DNA vaccine directing synthesis of the same TBI-HBsAg antigen boosted the antibody response to HIV in the blood serum; however, it had no effect on the high level of antibodies produced to HBV.Mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture.  相似文献   
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Every large clade of Eukarya has its own pattern of kinetid (flagellar apparatus) structure, which is stable and specific within the group, thereby being a good phylogenetic marker. The kinetid structure of sponge choanocytes might be a candidate for such marker for the phylogeny of Porifera. Kinetids of two heteroscleromorphs, Halichondria sp. (Suberitida) and Crellomima imparidens (Poecilosclerida), have been investigated here for the first time, and a reconstruction of the kinetid for each species is provided. The kinetids of both species comprise a flagellar kinetosome with a nuclear fibrillar root, a basal foot and satellite producing microtubules; a centriole is absent. Good resolution images reveal a new thin structure, the axial granule, in the flagellar transition zone which might be present in other sponges. The comparison of kinetids in investigated sponges revealed three types of kinetid in Demospongiae, and their distribution in the taxon has been shown on a molecular phylogenetic tree. Kinetid characters of the common ancestor of Demospongiae are discussed. J. Morphol. 277:925–934, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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PCR was used to amplify DNA fragments containing the genes for interferon γ (IFNγ)-binding proteins (IFNγBPs) of the variola virus (VARV) and monkeypox virus (MPXV). The genes were expressed from baculovirus DNAs in Sf21 insect cells. The recombinant proteins were isolated from the culture medium by affinity chromatography. PAGE and Western blot analysis of the culture media and affinity-purified recombinant proteins showed that, in contrast to their cell analogs, the viral IFNγBPs form dimers in the absence of the ligand, human IFNγ. The biological activity of recombinant IFNγBPs was inferred from suppression of the protective effect of human IFNγ on L68 cells infected with the mouse encephalomyocarditis virus. The viral proteins showed a dose-dependent IFNγ-neutralizing effect. The prospects of using IFNγBPs as IFNγ antagonists are discussed.  相似文献   
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Animal movements are of great importance in studying home ranges, migration routes, resource selection, and social interactions. The Global Positioning System provides relatively continuous animal tracking over time and long distances. Nevertheless, the continuous trajectory of an animal’s movement is usually only observed at discrete time points. Brownian bridge models have been used to model movement of an animal between two observed locations within a reasonably short time interval. Assuming that animals are in perpetual motion, these models ignore inactivity such as resting or sleeping. Using the latest developments in applied probability, we propose a moving–resting process model where an animal is assumed to alternate between a moving state, during which it moves in a Brownian motion, and a resting state, during which it does not move. Theoretical properties of the process are studied as a first step towards more realistic models for animal movements. Analytic expressions are derived for the distribution of one increment and two consecutive increments, and are validated with simulations. The induced bridge model conditioning on the starting and end points is used to compute an animal’s probability of occurrence in an observation area during the time of observation, which has wide applications in wildlife behavior research.  相似文献   
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The classical (for the Grad-Shafranov equation) formulation of the equilibrium problem for a cylindrical current-carrying plasma column is shown to admit multiple solutions. The multiple solutions are bifurcational in character and appear due to the nonlinearity of the equilibrium equation. This was demonstrated analytically using a stepped current profile as an example. Bifurcational solutions found for the cylindrical case survive in toroidal geometry too.  相似文献   
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The synthesis and structure-activity relationship (SAR) of a novel series of di-substituted imidazoles, derived from modification of DAPT, are described. Subsequent optimization led to identification of a highly potent series of inhibitors that contain a β-amine in the imidazole side-chain resulting in a robust in vivo reduction of plasma and brain Aβ in guinea pigs. The therapeutic index between Aβ reductions and changes in B-cell populations were studied for compound 10h.  相似文献   
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We have developed clickable active site-directed photoaffinity probes for γ-secretase which incorporate a photoreactive benzophenone group and an alkyne handle for subsequent click chemistry mediated conjugation with azide-linked reporter tags for visualization (e.g., TAMRA-azide) or enrichment (e.g., biotin-azide) of labeled proteins. Specifically, we synthesized clickable analogs of L646 (2) and L505 (3) and validated specific labeling to presenilin-1N-terminal fragment (PS1-NTF), the active site aspartyl protease component within the γ-secretase complex. Additionally, we were able to identify signal peptide peptidase (SPP) by Western blot analysis. Furthermore, we analyzed the photo-labeled proteins in an unbiased fashion by click chemistry with TAMRA-azide followed by in-gel fluorescence detection. This approach expands the utility of γ-secretase inhibitor (GSI) photoaffinity probes in that labeled proteins can be tagged with any number of azide-linked reporters groups using a single clickable photoaffinity probe for target pull down and/or fluorescent imaging applications.  相似文献   
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