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1.
The role of birds as sources of Shiga toxin-and intimin-producing Escherichia coli was studied. Fecal samples from live gulls (n=86), pigeons (n=33) and broiler chickens (n=199) from 23 flocks were analyzed for stx and eae by PCR. No stx positive samples were detected. In contrast, eae E. coli were highly prevalent among gulls (40%), and was also found in pigeons (7%) and chickens (57% of the flocks contaminated). The eae positive isolates were analyzed genetically and O-serogrouped. One isolate from a pigeon was found to have stx (2f). The isolates of gulls differed from those of pigeons and chickens, and all eae E. coli isolates from birds differed from human pathogenic strains by the lack of EHEC-hlyA and bfp/EAF as well as distribution of O-serogroups. Thus, birds cannot be regarded as important carriers of zoonotic stx or eae E. coli in Finland.  相似文献   
2.
The fatty acid composition and contents of fat and fat-soluble vitamins of three salted products prepared from Icelandic herring were analyzed. The effects of storage on the products over their shelf life, 6 or 12 months, were investigated. The average oil content of salted, gutted herring and salted fillets in vacuum remained constant, 17 and 12% of wet weight, respectively. In the pickled product the oil content decreased during the 12 months of storage from 13 to 12%. The composition of the products was typical for herring, the most abundant fatty acids being oleic (18:1n-9), palmitic (16:0), cetoleic (22:1n-11), and gadoleic (20:1n-9) acids. Monounsaturated acids constituted clearly the main group with a proportion of >50% of all fatty acids. Eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) comprised together >12% of all fatty acids. During storage, some hydrolysis of triacylglycerol (TAG) occurred, causing a slight reduction in practically all esterified fatty acids. In none of the three products was the loss of polyunsaturated fatty acids from TAG greater than the loss of saturated ones, indicating that the loss of EPA and DHA was not due to oxidation. After packing, the average content of vitamins A, D, and E in the products varied between 27 and 87 microg/100 g (wet weight), between 17-28 microg/100 g (wet weight), and between 77-120 microg/100 g (wet weight), respectively. During storage, the level of vitamin A decreased significantly, whereas no loss of vitamin D was observed. The content of vitamin E was low in all products and showed wide variation. When compared to the recommended daily intake, it could be concluded that the products investigated were good and stable sources of long-chain n-3 fatty acids (EPA, DHA) and vitamin D.  相似文献   
3.
Peat was employed as a biological filter material for the removal of hydrogen sulphide (H2> S) dimethyl sulphide (Me2S) and methyl mercaptan (MeSH) from odorous ventilation air. Removal of H2S was possible without the need to inoculate the filter material with oxidizing microbes whereas Me2S required inoculation for degradation. The removal of Me2S was decreased as a result of MeSH addition. Liming of the filter material, i.e., addition of calcium hydroxide, increased removal efficiency and activated the oxidation of H2S without any adaptation period. As a consequence of the poor Me2S removal efficiency of natural peat, a limed and inoculated biofilter was needed to purify mixtures of gases containing sulphur. The highest H2S load tested with limed but otherwise natural peat was 136 g-S m-3 day-1, yielding a 99 % reduction. The maximum Me2S elimination capacity with limed and inoculated peat was 175 g-S m-3day-1, but removal became unstable when the load exceeded 150 g-S m-3day-1. The maximum MeSH load tested was 107 g-S m-3day-1, yielding 98 % removal.  相似文献   
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Effects of the timing of soil thawing in the spring on Scots pine (Pinus sylvestris L.) were studied under controlled laboratory conditions. Sixteen 6-year-old saplings were lifted from the field, replanted in containers and placed in four treatments in controlled environment (CE) chambers with four replicate saplings per chamber. The saplings were held in the CE chambers during one simulated winter and one simulated growing season. The soil was frozen to -2 degrees C during a second simulated winter in the CE chambers, and the soil thawing treatments began at the end of the second simulated winter. Soil thawing began at various times before (no delay in thawing) and after (delay in thawing) chamber air conditions were changed from simulated winter to simulated summer. Delayed soil thawing subjected saplings to stress, with the severity of stress depending on the length of the delay in thawing. If there was no delay or only a short delay in soil thawing, stress was minor and reversible. A 2-week delay in soil thawing led to death of the saplings. Stress was apparent as decreases in the variable to maximal chlorophyll fluorescence ratio (Fv/Fm), chlorophyll a/b ratio and needle water potential. In needles of stressed saplings, apoplastic electrical resistance first decreased and then increased and there were anomalies in the electrical impedance spectra of the stems. Stress from the soil thawing treatments affected both root and shoot growth.  相似文献   
7.
We previously traced 10B-enriched boric acid from shoots to roots to demonstrate the translocation of boron (B) in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings. To gain a more detailed understanding of B translocation, we sought: (1) to demonstrate B retranslocation directly, by showing that foliar-applied 10B is located in the new growth after dormancy; and (2) to assess whether shoot-applied B affects growth in the long term. We applied 10B-enriched boric acid to needles of Scots pine and Norway spruce seedlings. After a dormancy period and 9 weeks of growth, small but significant increases in the 10B isotope were found in the new stem and needles of both species. In Scots pine, the total B concentration of the new stem was also increased. Both species contained polyols, particularly pinitol and inositol. Boron-polyol complexes may provide a mechanism for mobilizing B in these species. To determine the long-term effects of applied B, seedlings were grown for two growing seasons after the application of 10B to shoots. In Norway spruce, the proportion of 10B in the root systems and current needles of the harvest year was slightly higher than in the controls, and in Scots pine root systems, marginally so. The B treatment had no effect on growth of Norway spruce seedlings. In Scots pine seedlings, the B treatment caused a 33% increase in total dry mass and significantly increased the number of side branches.  相似文献   
8.
A 12-year-old castrated male West Highland White Terrier was referred because of recurrent episodes of collapsing. The dog was mildly anemic and severely thrombocytopenic and had high serum alanine aminotransferase activity. Infection with Bartonella vinsonii (berkhoffii) was initially diagnosed on the basis of serologic testing. Despite treatment with a series of antimicrobials and prolonged use of immunosuppressive drugs, thrombocytopenia persisted. After 5 months of treatment, Babesia canis organisms were seen during examination of a direct blood smear. The dog was treated with imidocarb dipropionate for babesiosis, after which thrombocytopenia resolved, and administration of immunosuppressive drugs was discontinued. Retrospective review of blood smears failed to identify organisms; however, polymerase chain reaction (PCR) analysis of multiple stored blood samples obtained during the 5-month period of persistent thrombocytopenia identified DNA of B. canis vogeli. Babesiosis may cause persistent, unexplained thrombocytopenia in dogs that are not anemic. A PCR assay can facilitate a diagnosis of babesiosis when organisms are not evident or when serologic testing fails to detect Babesia-specific antibodies.  相似文献   
9.
Regional cerebral metabolism and blood flow can be measured noninvasively with positron emission tomography (PET). 2‐[18F]fluoro‐2‐deoxy‐D‐glucose (FDG) widely serves as a PET tracer in human patients with epilepsy to identify the seizure focus. The goal of this prospective study was to determine whether juvenile or adult dogs with focal‐onset epilepsy exhibit abnormal cerebral glucose uptake interictally and whether glucose uptake changes with age. We used FDG‐PET to examine six Lagotto Romagnolo dogs with juvenile epilepsy, two dogs with adult‐onset epilepsy, and five control dogs of the same breed at different ages. Three researchers unaware of dog clinical status visually analyzed co‐registered PET and magnetic resonance imaging (MRI) images. Results of the visual PET analyses were compared with electroencephalography (EEG) results. In semiquantitative analysis, relative standard uptake values (SUV) of regions of interest (ROI) drawn to different brain regions were compared between epileptic and control dogs. Visual analysis revealed areas of hypometabolism interictally in five out of six dogs with juvenile epilepsy in the occipital, temporal, and parietal cortex. Changes in EEG occurred in three of these dogs in the same areas where PET showed cortical hypometabolism. Visual analysis showed no abnormalities in cerebral glucose uptake in dogs with adult‐onset epilepsy. Semiquantitative analysis detected no differences between epileptic and control dogs. This result emphasizes the importance of visual analysis in FDG‐PET studies of epileptic dogs. A change in glucose uptake was also detected with age. Glucose uptake values increased between dog ages of 8 and 28 weeks and then remained constant.  相似文献   
10.
In human epileptic patients, changes in cerebral glucose utilization can be detected 2‐deoxy‐2‐[18F] fluoro‐d ‐glucose positron emission tomography (FDG‐PET). The purpose of this prospective study was to determine whether epileptic dogs might show similar findings. Eleven Finnish Spitz dogs with focal idiopathic epilepsy and six healthy dogs were included. Dogs were examined using electroencephalography (EEG) and FDG‐PET, with epileptic dogs being evaluated during the interictal period. Visual and semi‐quantitative assessment methods of FDG‐PET were compared and contrasted with EEG findings. Three independent observers, unaware of dog clinical status, detected FDG‐PET uptake abnormalities in 9/11 epileptic (82%), and 4/8 healthy dogs (50%). Occipital cortex findings were significantly associated with epileptic status (P = 0.013). Epileptic dogs had significantly lower standardized uptake values (SUVs) in numerous cortical regions, the cerebellum, and the hippocampus compared to the control dogs. The lowest SUVs were found in the occipital lobe. White matter normalized and left‐right asymmetry index values for all pairs of homologous regions did not differ between groups. Visual evaluation of the EEGs was less sensitive (36%) than FDG‐PET. Both diagnostic tests were consensual and specific (100%) for occipital findings, but EEG had a lower sensitivity for detecting lateralized foci than FDG‐PET. Findings supported the use of FDG‐PET as a diagnostic test for dogs with suspected idiopathic epilepsy. Visual and semiquantitative analyses of FDG‐PET scans provided complementary information. Findings also supported the theory that epileptogenesis may occur in multiple brain regions in Finnish Spitz dogs with idiopathic epilepsy.  相似文献   
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