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31.
The natural division of the pig's liver into lobules was established at this stage without particular attention to the pattern of blood vessels—in order to explain missing relationships in the structure of the liver parenchyma. The results of the study, which diviate from what has been reported to date, enable us to give a first overview and make comparisons with histological sections. 相似文献
32.
Susan M. Newell DVM Mary B. Mahaffey DVM MS Royce E. Roberts DVM MS Ana Patricia Garcia DVM Anita R. Stampley DVM 《Veterinary radiology & ultrasound》1994,35(3):217-220
Laryngeal adenocarcinoma was diagnosed in a 5-year-old golden retriever dog with no history of respiratory or pharyngeal difficulties. Radiographically the basihyoid bone was destroyed by the neoplasm, and extensive soft tissue mineralization ventral to the larynx was also present. Complete surgical resection was not possible due to diffuse involvement of the tongue and larynx. Cobalt-60 teletherapy was used for treatment of the tumor. There was no clinical evidence of tumor regrowth at approximately 12 months post treatment. This is an unusual example of primary laryngeal neoplasia due to the absence of clinical respiratory abnormalities and the aggressive destruction of the basihyoid bone. 相似文献
33.
Dennison AC Van Metre DC Morley PS Callan RJ Plampin EC Ellis RP 《Journal of the American Veterinary Medical Association》2005,227(1):132-138
OBJECTIVE: To compare the frequency of isolation, genotypes, and in vivo production of major lethal toxins of Clostridium perfringens in adult dairy cows affected with hemorrhagic bowel syndrome (HBS) versus left-displaced abomasum (LDA). DESIGN: Case-control study. ANIMALS: 10 adult dairy cattle with HBS (cases) and 10 adult dairy cattle with LDA matched with cases by herd of origin (controls). PROCEDURE: Samples of gastrointestinal contents were obtained from multiple sites during surgery or necropsy examination. Each sample underwent testing for anaerobic bacteria by use of 3 culture methods. The genotype of isolates of C. perfringens was determined via multiplex polymerase chain reaction assay. Major lethal toxins were detected by use of an ELISA. Data were analyzed with multivariable logistic regression and chi2 analysis. RESULTS: C. perfringens type A and type A with the beta2 gene (A + beta2) were the only genotypes isolated. Isolation of C. perfringens type A and type A + beta2 was 6.56 and 3.3 times as likely, respectively, to occur in samples from cattle with HBS than in cattle with LDA. Alpha toxin was detected in 7 of 36 samples from cases and in 0 of 32 samples from controls. Beta2 toxin was detected in 9 of 36 samples from cases and 0 of 36 samples from controls. CONCLUSIONS AND CLINICAL RELEVANCE: C. perfringens type A and type A + beta2 can be isolated from the gastrointestinal tract with significantly greater odds in cattle with HBS than in herdmates with LDA. Alpha and beta2 toxins were detected in samples from cows with HBS but not from cows with LDA. 相似文献
34.
35.
Persistence of Mycoplasma gallisepticum in chickens after treatment with enrofloxacin without development of resistance 总被引:2,自引:0,他引:2
Reinhardt AK Gautier-Bouchardon AV Gicquel-Bruneau M Kobisch M Kempf I 《Veterinary microbiology》2005,106(1-2):129-137
The ability of the avian pathogen Mycoplasma gallisepticum to persist despite fluoroquinolone treatment was investigated in chickens. Groups of specific pathogen free chickens were experimentally infected with M. gallisepticum and treated with enrofloxacin at increasing concentrations up to the therapeutic dose. When M. gallisepticum could no longer be re-isolated from chickens, birds were stressed by inoculation of infectious bronchitis virus or avian pneumovirus. Although M. gallisepticum could not be cultured from tracheal swabs collected on several consecutive sampling days after the end of the enrofloxacin treatments, the infection was not eradicated. Viral infections reactivated the mycoplasma infection. Mycoplasmas were isolated from tracheal rings cultured for several days, suggesting that M. gallisepticum persisted in the trachea despite the enrofloxacin treatment. The minimal inhibitory concentration (MIC) of enrofloxacin for most of the re-isolated mycoplasmas was the same as that of the strain with which the birds were inoculated. Furthermore, no mutation could be detected in the fluoroquinolone target genes. These results suggest that M. gallisepticum can persist in chickens without development of resistance despite several treatments with enrofloxacin. 相似文献
36.
37.
Amrein TM Limacher A Conde-Petit B Amado R Escher F 《Journal of agricultural and food chemistry》2006,54(16):5910-5916
Fried potato products such as French fries and chips may contain substantial amounts of acrylamide. Numerous efforts are undertaken to minimize the acrylamide content of these products while sensory properties such as color and flavor have to be respected as well. An optimization of the frying process can be achieved if the basic kinetic data of the browning and acrylamide formation are known. Therefore, heating experiments with potato powder were performed under controlled conditions (moisture, temperature, and time). Browning and acrylamide content both increased with heating time at all temperatures and moisture contents tested. The moisture content had a strong influence on the activation energy of browning and acrylamide formation. The activation energy strongly increased at moisture contents below 20%. At higher moisture contents, it was very similar for both parameters. At low moisture contents, the activation energy of acrylamide formation was larger as compared to the one for browning. This explains why the end of the frying process is very critical. Therefore, a lower temperature toward the end of frying reduces the acrylamide content of the product while color development is still good. 相似文献
38.
Tiina Nokireki Taina Laine Laura London Niina Ikonen Anita Huovilainen 《Acta veterinaria Scandinavica》2013,55(1):69
Background
Swine influenza is an infectious acute respiratory disease of pigs caused by influenza A virus. We investigated the time of entry of swine influenza into the Finnish pig population. We also describe the molecular detection of two types of influenza A (H1N1) viruses in porcine samples submitted in 2009 and 2010.This retrospective study was based on three categories of samples: blood samples collected for disease monitoring from pigs at major slaughterhouses from 2007 to 2009; blood samples from pigs in farms with a special health status taken in 2008 and 2009; and diagnostic blood samples from pigs in farms with clinical signs of respiratory disease in 2008 and 2009. The blood samples were tested for influenza A antibodies with an antibody ELISA. Positive samples were further analyzed for H1N1, H3N2, and H1N2 antibodies with a hemagglutination inhibition test. Diagnostic samples for virus detection were subjected to influenza A M-gene-specific real-time RT-PCR and to pandemic influenza A H1N1-specific real-time RT-PCR. Positive samples were further analyzed with RT-PCRs designed for this purpose, and the PCR products were sequenced and sequences analyzed phylogenetically.Results
In the blood samples from pigs in special health class farms producing replacement animals and in diagnostic blood samples, the first serologically positive samples originated from the period July–August 2008. In samples collected for disease monitoring, < 0.1%, 0% and 16% were positive for antibodies against influenza A H1N1 in the HI test in 2007, 2008, and 2009, respectively. Swine influenza A virus of avian-like H1N1 was first detected in diagnostic samples in February 2009. In 2009 and 2010, the avian-like H1N1 virus was detected on 12 and two farms, respectively. The pandemic H1N1 virus (A(H1N1)pdm09) was detected on one pig farm in 2009 and on two farms in 2010.Conclusions
Based on our study, swine influenza of avian-like H1N1 virus was introduced into the Finnish pig population in 2008 and A(H1N1)pdm09 virus in 2009. The source of avian-like H1N1 infection could not be determined. Cases of pandemic H1N1 in pigs coincided with the period when the A(H1N1)pdm09 virus was spread in humans in Finland. 相似文献39.
Maćerak Anita Leovac Ivančev-Tumbas Ivana Börnick Hilmar Ilić Gordana Isakovski Marijana Kragulj Maletić Snežana 《Journal of Soils and Sediments》2019,19(2):964-972
Journal of Soils and Sediments - This study utilizes column tests to investigate the retardation of certain herbicides with different hydrophobicities (atrazine, alachlor and trifluralin) during... 相似文献
40.
Re-creation of heathland on improved pasture using top soil removal and sulphur amendments: Edaphic drivers and impacts on ericoid mycorrhizas 总被引:1,自引:0,他引:1
Understanding the factors that drive successful re-creation and restoration of lowland heaths is crucially important for achieving the long-term conservation of this threatened habitat type. In this study we investigated the changes in soil chemistry, plant community and interactions between Calluna vulgaris and symbiotic ericoid mycorrhizas (ERM) that occurred when improved pasture was subjected to one of three treatments (i) acidification with elemental sulphur (ii) acidification with ferrous sulphur (iii) removal of the topsoil. We found that the soil stripping treatment produced the greatest reduction in available phosphate but did not decrease soil pH. Conversely, acidification with elemental sulphur decreased pH but increased availability of phosphate and potentially toxic cations. The elemental sulphur treatment produced plant communities that most closely resembled those on surrounding heaths and acid grasslands. The most important driver was low pH and concomitant increased availability of potentially toxic cations. Plant community development was found to be little related to levels of available soil phosphate, particularly at low pH. The elemental sulphur treatment also produced the best germination and growth of C. vulgaris over 4-5 years. However, this treatment was found to inhibit the development of symbiotic relationships between C. vulgaris and ERM. This may affect the long-term persistence of re-created vegetation and its interactions with other components of heathland communities. 相似文献