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71.
Viruses have become a prominent issue in public health, politics and economics due to the Covid-19 pandemic. Yet they have still met little attention in educational research, although misconceptions concerning viruses may contribute to antibiotics misuse, disbelief in existence of viruses and distrust in vaccination. We investigated knowledge and attitudes in Austria concerning Covid-19, viruses in general and vaccination. We conducted two cross-sectional online surveys. Study A was performed Austrian-wide (N = 1027), study B specifically targeted Austrian students from middle and high schools (N = 1728). Several participants did not believe in the existence of SARS-CoV-2. General vaccination damage was highly overrated. Many defined viruses as unicellular organisms or bacteria, and 6-10 % believed that they can be killed by antibiotics. Very many participants were unable to identify, whether a specific disease was caused by a virus or another pathogen. Knowledge was significantly correlated with level of education/grade and interest in virology. Additionally, willingness to become vaccinated was significantly correlated with knowledge. Many participants felt insufficiently informed about viruses at school. We strongly recommend that virus-related school education must highly improve to enable the population to correctly assess health-related information, counter fake news and come to scientifically informed decisions. 相似文献
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74.
Tagging quantitative trait loci for maturity-corrected late blight resistance in tetraploid potato with PCR-based candidate gene markers 总被引:14,自引:0,他引:14
Bormann CA Rickert AM Ruiz RA Paal J Lübeck J Strahwald J Buhr K Gebhardt C 《Molecular plant-microbe interactions : MPMI》2004,17(10):1126-1138
Late blight caused by the oomycete Phytophthora infestans is the economically most important and destructive disease in potato cultivation. Quantitative resistance to late blight available in tetraploid cultivars is correlated with late maturity in temperate climates, which is an undesirable characteristic. A total of 30 DNA-based markers known to be linked to loci for pathogen resistance in diploid potato were selected and tested as polymerase chain reaction-based markers for linkage with quantitative trait loci (QTL) for late blight resistance and plant maturity in two half-sib families of tetraploid potatoes. Most markers originated from within or were physically closely linked to candidate genes for quantitative resistance factors. The families were repeatedly evaluated in the field for quantitative resistance to late blight and maturity. Resistance was corrected for the maturity effect. Nine of eleven different map segments tagged by the markers harbored QTL affecting maturity-corrected resistance. Interactions were found between unlinked resistance QTL, providing testable strategies for marker-assisted selection in tetraploid potato. Based on the linkage observed between QTL for resistance and plant maturity and based on the genetic interactions observed between candidate genes tagging resistance QTL, we discuss models for the molecular basis of quantitative resistance and maturity. 相似文献
75.
Kruse K Pantazis P Bollenbach T Jülicher F González-Gaitán M 《Development (Cambridge, England)》2004,131(19):4843-4856
Developing cells acquire positional information by reading the graded distribution of morphogens. In Drosophila, the Dpp morphogen forms a long-range concentration gradient by spreading from a restricted source in the developing wing. It has been assumed that Dpp spreads by extracellular diffusion. Under this assumption, the main role of endocytosis in gradient formation is to downregulate receptors at the cell surface. These surface receptors bind to the ligand and thereby interfere with its long-range movement. Recent experiments indicate that Dpp spreading is mediated by Dynamin-dependent endocytosis in the target tissue, suggesting that extracellular diffusion alone cannot account for Dpp dispersal. Here, we perform a theoretical study of a model for morphogen spreading based on extracellular diffusion, which takes into account receptor binding and trafficking. We compare profiles of ligand and surface receptors obtained in this model with experimental data. To this end, we monitored directly the pool of surface receptors and extracellular Dpp with specific antibodies. We conclude that current models considering pure extracellular diffusion cannot explain the observed role of endocytosis during Dpp long-range movement. 相似文献
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Colditz F Nyamsuren O Niehaus K Eubel H Braun HP Krajinski F 《Plant molecular biology》2004,55(1):109-120
The legume root rot disease caused by the oomycete pathogen Aphanomyces euteiches is one major yield reducing factor in legume crop production. A comparative proteomic approach was carried out in order to identify proteins of the model legume Medicago truncatula which are regulated after an infection with A. euteiches. Several proteins were identified by two dimensional gel electrophoresis to be differentially expressed after pathogen challenge. Densitometric evaluation of expression values showed different regulation during the time-course analysed. Proteins regulated during the infection were identified by matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Among the differentially expressed proteins, two encoded putative cell wall proteins and two were designated as small heat shock proteins. Furthermore, an isoform of the chalcone-O-methyltransferase was found to be increased in infected roots. The majority of induced proteins belonged to the family of class 10 of pathogenesis related proteins (PR10). Previously, various PR10-like proteins have been shown to be regulated by general stress or abscisic acid (ABA). Therefore, these proteins were further investigated concerning their regulation in response to drought stress and exogenous ABA-application. Complex regulation patterns were identified: three of the A. euteiches-induced PR10-like proteins were also induced by exogenous ABA- but none of them is induced after drought stress. In contrast, three of these proteins are down-regulated by drought stress. Hence, the strong expression of different PR10-family members and their regulation profiles indicates that this set of proteins plays a major role during root adaptations to various stress conditions. 相似文献
78.
Cryo-electron microscopy of vitreous sections 总被引:10,自引:0,他引:10
Al-Amoudi A Chang JJ Leforestier A McDowall A Salamin LM Norlén LP Richter K Blanc NS Studer D Dubochet J 《The EMBO journal》2004,23(18):3583-3588
Since the beginning of the 1980s, cryo-electron microscopy of a thin film of vitrified aqueous suspension has made it possible to observe biological particles in their native state, in the absence of the usual artefacts of dehydration and staining. Combined with 3-d reconstruction, it has become an important tool for structural molecular biology. Larger objects such as cells and tissues cannot generally be squeezed in a thin enough film. Cryo-electron microscopy of vitreous sections (CEMOVIS) provides then a solution. It requires vitrification of a sizable piece of biological material and cutting it into ultrathin sections, which are observed in the vitrified state. Each of these operations raises serious difficulties that have now been overcome. In general, the native state seen with CEMOVIS is very different from what has been seen before and it is seen in more detail. CEMOVIS will give its full potential when combined with computerized electron tomography for 3-d reconstruction. 相似文献
79.
O'Donoghue SI Meyer JE Schafferhans A Fries K 《Bioinformatics (Oxford, England)》2004,20(15):2476-2478
In this paper we present SRS 3D, a new service that allows users to easily and rapidly find all related structures for a given target sequence; structures can then be viewed together with sequences, alignments and sequence features (currently from UniProt, InterPro and PDB). Extensive user feedback confirms that SRS 3D is intuitive and useful especially for those not expert in structures. AVAILABILITY: An SRS 3D server is provided at http://srs3d.ebi.ac.uk/. 相似文献
80.
Mullett WM Walles M Levsen K Borlak J Pawliszyn J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,801(2):297-306
A new molecularly imprinted polymer (MIP) material was synthesized selective for verapamil and utilized for on-line metabolic screening of this common calcium antagonist in biological samples. Since some metabolites of verapamil have also shown pharmacological properties, a selective and sensitive sample preparation approach that provides a metabolic profile in biologically relevant samples is important. The MIP material was coupled on-line to a restricted access material (RAM) precolumn. The multidimensional nature of this set-up removed large matrix interferents such as proteins from the sample, while the selectivity of the MIP enabled further cleanup of the smaller analytes. The selectivity and extraction efficiency of the MIP for verapamil and its metabolites was evaluated in various biological matrices, such as cell cultures and urine. The experimental set-up with the developed method enabled the direct injection of biological samples for the selective isolation, preconcentration, identification and analysis of verapamil and its phase I metabolites by LC-MS(n). This multidimensional approach provided much qualitative information about the metabolic profile of verapamil in various biological matrices. An analytical method was developed for the quantification of verapamil and gallopamil in urine, plasma and cell culture. Acceptable linearity (R(2)=0.9996, 0.9982 and 0.9762) with an average injection repeatability (n=3) of 10, 25 and 15% R.S.D. was determined for urine, plasma and cell culture, respectively. This is the first application of the procedure for the selective metabolic screening of verapamil in biological samples. 相似文献