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461.
462.
T M Kloppel C P Franz D J Morré R C Richardson 《American journal of veterinary research》1978,39(8):1377-1380
Serum concentrations of lipid-soluble (glycolipid) sialic acid were determined for 96 client-owned dogs, of which 24 were diagnosed as bearing tumors. A markedly increased concentration of lipid-soluble serum sialic acid was found in 22 of 24 tumor-bearing dogs (92%) compared with 17 of 72 dogs with other definitely false-positive, based on necropsy and follow-up work. Almost all others had acute infections or terminal congestive disorders and were potential tumor bearers. The values obtained appeared to be independent of the sex or age (or both) of the dogs. Based on the analysis of a single biochemical variable, the procedure may permit cancer detection applicable to a wide range of tumor types in dogs if evaluated in terms of the general health status of the animal. 相似文献
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466.
Franz S Hofmann-Parisot M Baumgartner W Windischbauer G Suchy A Bauder B 《The Veterinary record》2001,149(4):109-112
When the isolated teat of a cow was examined with an 8.5 MHz linear array transducer in a vertical plane, the teat canal appeared as a thin, white line, bordered on each side by parallel, thick, grey-black bands. In a horizontal plane a comparable image was obtained. In a sheep, images of comparable quality were obtained with a 12 MHz transducer. Histological studies of the tissues whose removal led to the disappearance of this characteristic ultrasonographic appearance showed that it was associated with the stratified keratinised squamous epithelium with distinct papillae. The content of keratin in the stratum corneum was apparently responsible for the bright zone; the stratum lucidum was not visible, and the surrounding dark, less echoic area was associated with the stratum granulosum. Doppler echography in live animals confirmed this designation. The outer layers of the teat wall were more echogenic. 相似文献
467.
468.
Rubel F Brugger K Hantel M Chvala-Mannsberger S Bakonyi T Weissenböck H Nowotny N 《Preventive veterinary medicine》2008,85(3-4):166-186
Usutu virus (USUV), a flavivirus of the Japanese encephalitis virus complex, was for the first time detected outside Africa in the region around Vienna (Austria) in 2001 by Weissenb?ck et al. [Weissenb?ck, H., Kolodziejek, J., Url, A., Lussy, H., Rebel-Bauder, B., Nowotny, N., 2002. Emergence of Usutu virus, an African mosquito-borne flavivirus of the Japanese encephalitis virus group, central Europe. Emerg. Infect. Dis. 8, 652-656]. USUV is an arthropod-borne virus (arbovirus) circulating between arthropod vectors (mainly mosquitoes of the Culex pipiens complex) and avian amplification hosts. Infections of mammalian hosts or humans, as observed for the related West Nile virus (WNV), are rare. However, USUV infection leads to a high mortality in birds, especially blackbirds (Turdus merula), and has similar dynamics with the WNV in North America, which, amongst others, caused mortality in American robins (Turdus migratorius). We hypothesized that the transmission of USUV is determined by an interaction of developing proportion of the avian hosts immune and climatic factors affecting the mosquito population. This mechanism is implemented into the present model that simulates the seasonal cycles of mosquito and bird populations as well as USUV cross-infections. Observed monthly climate data are specified for the temperature-dependent development rates of the mosquitoes as well as the temperature-dependent extrinsic-incubation period. Our model reproduced the observed number of dead birds in Austria between 2001 and 2005, including the peaks in the relevant years. The high number of USUV cases in 2003 seems to be a response to the early beginning of the extraordinary hot summer in that year. The predictions indicate that >70% of the bird population acquired immunity, but also that the percentage would drop rapidly within only a couple of years. We estimated annually averaged basic reproduction numbers between R (0)=0.54 (2004) and 1.35 (2003). Finally, extrapolation from our model suggests that only 0.2% of the blackbirds killed by USUV were detected by the Austrian USUV monitoring program [Chvala, S., Bakonyi, T., Bukovsky, C., Meister, T., Brugger, K., Rubel, F., Nowotny, N., Weissenb?ck, H., 2007. Monitoring of Usutu virus activity and spread by using dead bird surveillance in Austria, 2003-2005. Vet. Microbiol. 122, 237-245]. These results suggest that the model presented is able to quantitatively describe the process of USUV dynamics. 相似文献
469.
Freuling C Grossmann E Conraths FJ Schameitat A Kliemt J Auer E Greiser-Wilke I Müller T 《Veterinary microbiology》2008,131(1-2):26-34
In Europe, rabies in bats is caused by European Bat Lyssavirus (EBLV) type 1 (EBLV-1) or type 2 (EBLV-2) which form two distinct genotypes (gt 5 and 6) within the genus Lyssavirus of the family of Rhadoviridae. Spill-over infections of EBLV in humans have caused fatal rabies encephalitis and highlighted the relevance of this wildlife disease for public health. The vast majority of the 831 European bat rabies cases reported between 1977 and 2006 were identified as EBLV-1. Only few virus isolates originating from Switzerland, The Netherlands and the United Kingdom were characterized as EBLV-2. Here we report the first EBLV-2 case detected in Germany in a Daubenton's bat (Myotis daubentonii) in August 2007. The bat showed clinical signs of disorders of the central nervous system and subsequently tested positive for rabies. The virus was isolated and characterized as EBLV-2 based on its antigen pattern and by nucleotide sequencing. Phylogenetic analysis indicated an association to EBLV-2 isolates from Switzerland which correlates with the origin of the bat close to the Swiss border. 相似文献
470.
Kerstin Wernike Franz Conraths Gina Zanella Harald Granzow Kristel Gache Horst Schirrmeier Stephen Valas Christoph Staubach Philippe Marianneau Franziska Kraatz Detlef Höreth-Böntgen Ilona Reimann Stéphan Zientara Martin Beer 《Preventive veterinary medicine》2014
In autumn 2011, a novel species of the genus Orthobunyavirus of the Simbu serogroup was discovered close to the German/Dutch border and named Schmallenberg virus (SBV). Since then, SBV has caused a large epidemic in European livestock. Like other viruses of the Simbu serogroup, SBV is transmitted by insect vectors. Adult ruminants may show a mild transient disease, while an infection during a critical period of pregnancy can lead to severe congenital malformation, premature birth or stillbirth. The current knowledge about the virus, its diagnosis, the spread of the epidemic, the impact and the possibilities for preventing infections with SBV is described and discussed. 相似文献