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Corynebacterium silvaticum is a newly identified animal pathogen of forest animals such as roe deer and wild boars. The species is closely related to the emerging human pathogen Corynebacterium ulcerans and the widely distributed animal pathogen Corynebacterium pseudotuberculosis. In this study, Corynebacterium silvaticum strain W25 was characterized with respect to its interaction with human cell lines. Microscopy, measurement of transepithelial electric resistance and cytotoxicity assays revealed detrimental effects of C. silvaticum to different human epithelial cell lines and to an invertebrate animal model, Galleria mellonella larvae, comparable to diphtheria toxin-secreting C. ulcerans. Furthermore, the results obtained may indicate a considerable zoonotic potential of this newly identified species.  相似文献   
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The presence of protease inhibitors in soybean prohibits the utilisation of the raw beans for food and feed. However, little information is available about environmental influences and the effects of nitrogen and sulphur supply on the antinutritional constituents of soybean. As these factors may influence protease inhibitors, soybean genotypes segregated according to the presence or absence of the Kunitz trypsin inhibitor have been evaluated for trypsin inhibitor activity (TIA) in field trials. TIA was affected significantly by environment (geographical location), fertilisation treatment and genotype. Environmental means of TIA were between 69.5 and 104.8 mg g?1. Nitrogen application, which caused an increase in seed protein content, resulted in a reduction in TIA by about 15% as compared with the control. Remarkably, simultaneous application of nitrogen and sulphur in the form of ammonium sulphate had a similar reductive effect on TIA to that of nitrogen application alone, although soybean protease inhibitors are rich in sulphur amino acids. Significant genetic variation in TIA was found both within the genotype class with the Kunitz inhibitor present as well as within the class lacking this inhibitor. The results suggest that TIA of soybean may be modified considerably by genetic improvement and appropriate agronomic management. Copyright © 2003 Society of Chemical Industry  相似文献   
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The frequencies of multinational papers in various sciences   总被引:2,自引:1,他引:1  
Multinational papers are defined here as ones written by authors who reside in different countries during the course of research. For each of 16 fields of science, I scanned the first 200 papers in 2005 in four major journals publishing original research papers. Those journals produced 40% of all the citations among those journals with Impact Factors greater than 1.0. The frequencies of multinational papers ranged from 13% in surgery to 55% in astronomy. Although one can list a dozen factors which might contribute toward multinational papers, I lack the data to test most of those. There are only minor correlations with team sizes and Impact Factors, inadequate to explain the range. There is a larger, but not convincing, dependence upon the fractions of single-author papers and its cause, if real, is unclear. However, the most prominent factor seems to be the nature of the objects studied; if they are usually local (e.g. in one hospital or in one laboratory), the papers tend to be domestic but if most of the objects are available simultaneously to scientists in many countries (e.g. the sky in astronomy or the oceans and the Earth’s atmosphere in geosciences or widespread diseases in the area of infectious diseases or plants and animals widely distributed in biology), the papers are often international. Auxiliary results for 2005 are an average of 5.5 ± 0.3 authors per paper and 6.6 ± 1.0% one-author papers.  相似文献   
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A new on-line texture-analyzing system and its application to nondestructive r value determination is discussed. In addition to providing a brief theoretical background and describing the instrumental set-up, the article presents off-line measurements with this equipment and demonstrates the high accuracy of the determined r-values. A special feature of the unit is the possibility to simultaneously measure the most important r values—r0, r45, r90, and rm.  相似文献   
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