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51.
Areas a few square metres in size, devoid of higher vegetation other than moss, have been mapped at 600–700 m above sea level in the mountains of the western part of central Norway. The moss is covered by a grey precipitate during dry summer periods. The precipitate has been identified by ICP-AES analysis of HNO3-extract, X-ray diffraction (XRD) and by scanning electron microscopy (SEM) as an aluminium(Al)-hydroxide, probably amorphous Al-hydroxide and diaspore (Al(OH)3), containing 21–25% Al by weight. In comparison, the underlying moraine deposits contain 1.5–3.5% Al by weight. A small spring, where groundwater discharges, is located uphill of each contaminated area. The Al content of the water which emerges from these springs decreases downhill away from the spring and is inversely proportional to the pH. The runoff waters originating at the springs have been modelled using the computer-codes MINTEQA2 and ALCHEMI and are found to be saturated with respect to amorphous Al(OH)3. This study raises the very important question as to what extent a lower pH in the influent meltwater may leach out more aluminium and possibly lead to the formation of larger amounts of precipitate.  相似文献   
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With the aim to extend the present knowledge on possible systemic spreading of Pasteurella multocida in pigs with bronchopneumonia, the occurrence and associated lesions of P. multocida were described by comparing cultural detection, pathological evaluation and in situ hybridization of P. multocida in lungs, hearts and kidneys from cases of porcine bronchopneumonia. P. multocida was cultivated from the lung lesions in 114 out of a total of 148 cases of porcine bronchopneumonia. Among the 114 cases, P. multocida was also cultivated from the pericardial sacs of 40 pigs and the kidneys of seven pigs. Gross lesions and histological findings included a variety of type and stages of bronchopneumonia in connection to the isolation of P. multocida. Furthermore, chronic fibrous pericarditis, interstitial nephritis and a high proportion of lympho-histocytic nephritis were observed. In situ hybridization identified P. multocida in the majority of the lungs, none of the hearts and in half of the kidneys examined. The results show a possible low rate of systemic spreading of P. multocida from lung lesions in pigs with bronchopneumonia.  相似文献   
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We tested whether the spatiotemporal distribution of Norway spruce (Picea abies) logs influenced species richness and abundances of wood-decaying fungi in two 2-km2 boreal forest study sites in southeastern Norway. According to the random sample null-hypothesis equally large subsamples of logs should be equally efficient in sampling fungi from a regional species pool. Based on 0.25-ha plots at 1-ha grid resolution, we compared plots with high and low densities of ‘new logs’ (decay stages 1-5) and plots with ‘old logs’ (decay stages 5-8) present or absent. Based on visible sporocarps, 45 fungus species, including 15 redlisted, were identified among 4151 logs. When rarefying species accumulation curves to the same number of logs, we found no difference in species richness between old forest plots having high and low densities of new logs, or between plots where old logs were present or absent. Curves from young forest revealed fewer species than in old forest. Multiple regression analysis of six redlisted and six common species corroborated the rarefaction analysis in showing that the probability of occurrence was independent of the spatiotemporal distribution of logs for all but two common species. Aside from the fact that more dead wood harboured more wood-decaying fungi, we conclude that the spatiotemporal distribution of dead wood was of minor importance in determining species richness and abundances at the scales of <1 ha and <100 years. This suggests that wood-decaying fungi are not dispersal-limited at these scales, and it offers an optional element in forest management.  相似文献   
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Trehalose-negative strains of the Pasteurella haemolytica complex have recently been transferred to a new genus, Mannheimia. This genus presently consists of five named species: M. haemolytica, M. glucosida, M. granulomatis, M. ruminalis and M. varigena. The purpose of this study was to investigate the occurrence of these species and lesions associated with these isolates in Denmark. In all 106 M. haemolytica-like strains isolated from pathological material from cattle, sheep, pigs and hares submitted to the Danish Veterinary Laboratory between 1994 and 1998 were investigated. Phenotypic characterization and ribotyping were used for identification in addition to sequencing of the 16S rRNA genes for selected strains. The species allocation was determined by comparison to results from a previous polyphasic taxonomic study. Seventy-one percent of the strains belonged to M. haemolytica, 18% to M. varigena and 8% to unnamed groups within the genus Mannheimia. Single isolates identified as M. glucosida and P. trehalosi, respectively, were detected. Two isolates belonged to M. granulomatis. Forty-three percent of the strains belonged to serotype 1, 41% were untypeable, while the rest belonged to serotypes 2, 7, 9, and 16. The present investigation also showed that a simplified phenotypic characterization using Diatabs Diagnostic Tablets (Rosco, Denmark) represents a useful method for obtaining a quick and reliable species identification. Finally, the investigation confirmed that serotyping does not represent a reliable method for species identification. The heterogeneity of species associated with bovine "pasteurellosis" should be considered in future studies to improve our understanding of the pathogenesis of pneumonic disease.  相似文献   
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A common bile duct obstruction was documented in a dog, by performing cholecystography haparoscopic visualization facilitated performance of the cholecystography. Target cells were a consistent hematologic finding. Cholecystoduodenostomy, an easily performed surgical technique, allowed for restoration of bile flow and resolution of clinical signs.  相似文献   
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One hundred and two strains of Campylobacter fetus subsp. jejuni isolated from pigs, various avian species and man were subjected to biochemical characterization including hydrolysis of hippurate, tolerance of 3.5 % saline, H2S production in TSI medium, growth on TTC agar and antibiotic sensitivity. On this basis the porcine strains could be classified into 4 groups, while the avian and human strains could each be divided into 2 groups. The avian and human strains had the same biochemical characteristics as 2 of the porcine groups.  相似文献   
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The taxonomy of the members of the genus Actinobacillus associated with animals has been reviewed with focus on classification and identification including molecular based characterization, typing and identification. Out of the 22 species or species like taxa reported as Actinobacillus, 19 are associated with animals. When classified on the basis of 16S rRNA sequence based phylogenetic analysis, DNA-DNA hybridizations and phenotypic analysis, Actinobacillus sensu stricto is restricted to include A. lignieresii, A. pleuropneumoniae, A. equuli subsp. equuli, A. equuli subsp. haemolyticus (taxon 11 of Bisgaard), A. hominis, A. suis, A. ureae, A. arthritidis (taxon 9 of Bisgaard), Actinobacillus genomospecies 1 and 2 and the taxa 8 and 26 of Bisgaard. The remaining 11 species of Actinobacillus are unrelated to A. sensu stricto and should consequently be grouped with other genera or be renamed as new genera depending on new data. Identification of members of Actinobacillus at species level is possible through phenotypic characterization combined with information on host of isolation. PCR tests are available for specific detection of A. pleuropneumoniae. Only A. pleuropneumoniae is presently considered as a primary pathogen. Based on different types of RTX genes it is possible to PCR type A. pleuropneumoniae to serotype level. PCR might also be used for the specific detection of A. equuli subsp. haemolyticus. Epidemiological investigations and surveillance have so far included serotyping, multilocus enzyme electrophoresis (MLEE), ribotyping and restriction fragment length profiling.  相似文献   
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