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排序方式: 共有474条查询结果,搜索用时 15 毫秒
21.
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Franz F 《Science (New York, N.Y.)》1949,109(2836):466-467
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Wagner M Hein I Grif K Sumerkan AB Esel D Allerberger F 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(11-12):460-466
Research on the pathogen Listeria monocytogenes is a key issue both for the clinical and the food microbiologist owing to the unique pathway of infection and the exposure of humans via contaminated foods. Although, in Austria, the incidence of listeriosis is about 870-fold lower than the incidence for Salmonella infection, the food law manages both foodborne pathogens with a comparable stringency. The current risk management is based on the assumption that environmental L. monocytogenes isolates, from which the pool of "foodborne" isolates is recruited, are of similar pathogenicity compared to clinical and outbreak isolates. This verdict became doubted in the recent years. Characterization of L. monocytogenes by virulence gene sequencing, virulence studies in vivo and in vitro and by molecular typing was considerably stimulating the discussion on virulence variability in L. monocytogenes. This article provides insights in the value of epidemiological follow-up studies by presenting a typing study on 15 cases of listeriosis observed in a district hospital in Turkey. Furthermore results from typing L. monocytogenes either by virulence gene sequencing, mismatch amplification mutation assay or by pulsed field gel electrophoresis are discussed. The close interaction of molecular microbiology with food microbiology both in applied and basic science is currently creating a new discipline of molecular food microbiology. We are convinced that veterinary medicine will contribute to this exiting development in a fruitful way. 相似文献
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Otmar Spring Mark Bachofer Marco Thines Alexandra Riethmüller Markus Göker Franz Oberwinkler 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):309-315
Sequence parts of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were analysed to screen for the intraspecific
variability of a non-coding genomic region in 15 Plasmopara halstedii populations of different pathotype and geographic origin. Samples revealed uniformity in a ca. 790 Bp fragment comprising
of the ITS-1, 5.8S and front parts of the ITS-2. In contrast, clear differences were found in a ca. 810 Bp fragment of the
ITS-2 thus allowing differentiation between populations of pathotype 100, 310 and 330 and a group of populations representing
pathotypes 700, 701, 703, 710 and 730. Samples of pathotypes 700 to730 originated from Slovakia, France, and Germany, but
were uniform in both ITS sequence parts, thus indicating very recent origin of these highly aggressive physiological races.
The potential use of ITS sequences for pathotype differentiation and phylogenetic studies in P. halstedii is discussed. 相似文献
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Franz Bichlmaier 《European Journal of Forest Research》1970,89(1):356-362
Summary One of the essential aims of land planning is to satisfy the people's need for recreation. For this purpose it seems to be
efficient to differentiate between “local” recreation and “long-distance” recreation areas and to consider them separatly
in regional planning. To determine the location of recreational forests we need appropriate aids for decision making. Therefore
activities that bring about deterioration of natural conditions, e.g. water pollution, soil erosion etc., as well as injuries
to the optical value of the landscape, are not allowed in natural recreational areas. On the other hand it is possible to
delimit forests after an analysis of stand composition and also by interpretation of maps giving the physiological effects
of the climate.
Above all the habits of the people are of importance, especially when they are based on irrational motives. These factores
are of great importance in addition to the sociological conditions of an area and therefore do not allow the organization
of long-distance recreation areas from simply a regional point of view. In the case of areas designed for local recreation,
however, it might be sufficient to appraise the demands of the people through a regional analysis.
Herrn Professor Dr. Dr. h. c.Julius Speer zum 65. Geburtstag gewidmet. 相似文献
Herrn Professor Dr. Dr. h. c.Julius Speer zum 65. Geburtstag gewidmet. 相似文献
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