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21.
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
22.
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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24.
Conraths FJ Köhler H Werner O Beer M Depner KR Geue L Kaden V Staubach C Pötzsch C Schares G Mettenleiter TC 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(9-10):354-364
The Friedrich-Loeffler-Institut, founded in 1910 by Friedrich Loeffler, the discoverer of the first animal virus, foot-and-mouth disease virus, is the oldest virological research facility in the world. Beyond viruses, its area of competence has significantly expanded since its foundation and now also covers bacterial, parasitic and prion diseases of livestock, poultry and aquatic animals. Presently located at four sites within Germany (Insel Riems, Jena,Tübingen,Wusterhausen) the tasks of the institute as delineated in the Animal Disease Act encompass research on infectious animal diseases including zoonoses, import/export examinations, epidemiological studies in case of outbreaks of notifiable animal diseases, acting as reference laboratory for notifiable animal diseases and nationwide quality management of diagnosis of notifiable animal diseases. It is obliged to publish and maintain up-to-date diagnostic regimes for notifiable animal diseases, and it publishes a yearly report on animal health in Germany. With the increasing importance of infectious diseases of animals, in particular those potentially harmful to man (zoonoses), the Friedrich-Loeffler-Institut will be moving into new facilities including laboratories and animal facilities up to the highest biosafety level at its main site Insel Riems on the occasion of its 100th anniversary. 相似文献
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26.
Nitrate‐N uptake from soil depends on root growth and uptake activity. However, under field conditions N‐uptake activity is difficult to estimate from soil‐N depletion due to different loss pathways. We modified the current mesh‐bag method to estimate nitrate‐N‐uptake activity and root growth of two oilseed‐rape cultivars differing in N‐uptake efficiency. N‐efficient cultivar (cv.) ‘Apex' and N‐inefficient cv. ‘Capitol' were grown in a field experiment on a silty clayey gleyic fluvisol near Göttingen, northern Germany, and fertilized with 0 (N0) and 227 (N227) kg N ha–1. In February 2002, PVC tubes with a diameter of 50 mm were installed between plant rows at 0–0.3 and 0–0.6 m soil depth with an angle of 45°. At the beginning of shooting, beginning of flowering, and at seed filling, the PVC tubes were substituted by PVC tubes (compartments) of the same diameter, but with an open window at the upper side either at a soil depth of 0–0.3 or 0.3–0.6 m allowing roots to grow into the tubes. Anion‐exchange resin at the bottom of the compartment allowed estimation of nitrate leaching. The compartments were then filled with root‐free soil which was amended with or without 90 mg N (kg soil)–1. The newly developed roots and nitrate‐N depletion were estimated in the compartments after the installing period (21 d at shooting stage and 16 d both at flowering and grain‐filling stages). Nitrate‐N depletion was estimated from the difference between NO ‐N contents of compartments containing roots and control compartments (windows closed with a membrane) containing no roots. The amount of nitrate leached from the compartments was quantified from the resin and has been taken into consideration in the calculation of the N depletion. The amount of N depleted from the compartments significantly correlated with root‐length density. Suboptimal N application to the crop reduced total biomass and seed‐yield formation substantially (24% and 38% for ‘Apex’ and ‘Capitol’, respectively). At the shooting stage, there were no differences in root production and N depletion from the compartments by the two cultivars between N0 and N227. But at flowering and seed‐filling stages, higher root production and accordingly higher N depletion was observed at N0 compared to N227. Towards later growth stages, the newly developed roots were characterized by a reduction of root diameter and a shift towards the deeper soil layer (0.3–0.6m). At low but not at high N supply, the N‐efficient cv. ‘Apex’ exhibited higher root growth and accordingly depleted nitrate‐N more effectively than the N‐inefficient cv. ‘Capitol’, especially during the reproductive growth phase. The calculated nitrate‐N‐uptake rate per unit root length was maximal at flowering (for the low N supply) but showed no difference between the two cultivars. This indicated that the higher N‐uptake efficiency of cv. ‘Apex’ was due to higher root growth rather than higher uptake per unit of root length. 相似文献
27.
Objective
To evaluate the transdermal local anaesthetic effect of lidocaine or lidocaine combined with prilocaine or tetracaine in horses.Study design
Experimental, randomized study.Animals
A total of five healthy adult warmblood horses.Methods
Horses were clipped bilaterally at the withers, cranial saddle area and caudal saddle area. Baseline measurements for mechanical superficial sensation via von Frey filaments and nociceptive thermal thresholds were performed. A 5% lidocaine patch (12 hour exposure, treatment L), a lidocaine/prilocaine cream (each 2.5%, treatment LP) and a lidocaine/tetracaine cream (each 7%, treatment LT) were applied (both 2 hour exposure). The same product was applied at the same location bilaterally, but on the right side an epidermal micro-perforation (dermaroller, 1200 needles) was performed prior to application. A total of five more measurements were performed at each location, immediately at the end of exposure time followed by hourly measurements. Thermal thresholds normalized to thermal excursion were analysed. One- or two-way anova and the Wilcoxon signed-rank test were used for statistical analysis with p < 0.05 considered significant.Results
Epidermal micro-perforation had no enhancing effect. Treatments L, LP, and LT resulted in increased thermal excursion (%) immediately (84.7 ± 12.9; 100.0 ± 0.0; 100.0 ± 0.0) and 1 hour (81.7 ± 66; 86.0 ± 17.7; 87.7 ± 14.4) after the removal of the respective product compared to baseline (66.1 ± 9.3; 69.9 ± 8.3; 76.5 ± 7.8). Superficial mechanical sensation was decreased by the lidocaine-and-tetracaine cream at all time points, and by the lidocaine patch and lidocaine-and-prilocaine cream for three measurements.Conclusions and clinical relevance
Eutectic mixtures of lidocaine with either prilocaine or tetracaine led to a reduction in thermal nociception and mechanical sensation for up to 2 hours. 相似文献28.
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
29.
30.