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Ohne Zusammenfassung 相似文献
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A. S. J. P. A. M. VAN MIEKT C. T. M. VAN DUIN Th. WENSING† 《Journal of veterinary pharmacology and therapeutics》1992,15(4):332-342
Tumour necrosis factor (TNF), a polypeptide produced by mononuclear phagocytes, has been implicated as an important mediator of inflammatory processes and of clinical manifestations in acute infectious diseases. To study further the potential role of TNF in infectious diseases, recombinant Escherichia coli (E. coli) derived human (r.HuTNF-alpha) and bovine TNF (r.BoTNF-alpha) were intravenously (i.v.) administered in dwarf goats. Rectal temperature, heart rate, rumen motility, plasma zinc and iron concentrations, and certain other blood biochemical and haematological values were studied and compared with the changes seen after E. coli endotoxin (LPS) was administered (dose: 0.1 microgram/kg i.v.). Following a single injection of 4 micrograms/kg of r.BoTNF-alpha, shivering and biphasic febrile response were observed, accompanied by tachycardia, inhibition of rumen contractions, drop in plasma zinc and iron concentrations, lymphopenia, and neutropenia followed by neutrophilia. The i.v. administration of a single injection of 4 micrograms/kg r.HuTNF-alpha induced shivering and biphasic febrile responses, accompanied by anorexia and a similar drop in plasma trace metal concentrations when compared with r.BoTNF-alpha-treated goats. The TNF-alpha-induced symptoms were essentially the same as those that occurred after LPS administration. However, the time of onset of these changes after the injection of TNF-alpha was significantly shorter than after LPS. Moreover, the r.BoTNF-alpha induced a longer lasting neutrophilic leucopenia, less neutrophilia, and a more persistent lymphopenia than after LPS injection. Neither r.BoTNF-alpha nor LPS caused severe haemo-concentration. Furthermore, no cross-tolerance between r.BoTNF-alpha and LPS could be demonstrated. We conclude that both r.BoTNF-alpha and r.HuTNF-alpha induce many of the physiologic, haematologic and metabolic changes that characterize the acute phase response to LPS. The overlapping biological activities of r.BoTNF-alpha, r.HuTNF-alpha and LPS in dwarf goats may indicate that both recombinant tumour necrosis factors have some homology with caprine TNF-alpha. 相似文献
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Malestein A Geurink JH Schuyt G Schotman AJ Kemp A Th van 't Klooster A 《The Veterinary quarterly》1980,2(3):149-159
Summary In a series of experiments the effect of administering KNO(2) was studied, during parturition, on the capability of oxygen transport of maternal blood and on oxygen transfer to foetal blood. The following blood parameters were analysed, MHb percentage, pO(2), O(2)-saturation, pH, pCO(2), and (NO(2)) in maternal arterial blood (carotid art.) and venous blood (jugular vein) and in foetal arterial blood (umbilical art.) and venous blood (umbilical vein). The relative O(2)-saturation was calculated from the estimated O(2)-saturation by multiplying with the factor Hb (mmol/1) minus MHb (mmol/1), divided by Hb (mmol/1). In addition, blood pressure in the carotid artery, heart rate, and respiration rate in the dam were continuously recorded for some hours. A dosage of 9 to 12 mg of NO(2)/kg body weight intravenously or of 30 mg of NO(2)/kg body weight orally to the dam caused much higher MHb percentages and NO(2) contents in the maternal blood than in the foetal blood. In maternal blood the ratio of NO(2) content td MHb percentage was proportional to that in foetal blood. In the arterial blood, MHb percentages were almost as high as in the venous blood. After administering of nitrite, relative O(2)-saturation dropped simultaneously with the increase in methaemoglobin. Nitrite treatment caused a drop in the maternal blood pressure; heart rate and respiration rate increased. O(2)-saturation in the blood in the umbilical vein was much lower in the animals with nitrite treatment than in those without. These experimental results show clearly that the oxygen capacity of the blood decreases after nitrite treatment. In pregnant cows the oxygen supply to the foetus will be adversely affected after nitrate intake, especially by the lower oxygen transfer via the placenta, though hardly at all by methaemoglobin formation in the foetal blood. When the oxygen transfer to the foetal blood decreases too sharply, intra-uterine death and ultimately abortion may result. 相似文献
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R. A. A. van der Vlugt C. Cuperus J. Vink I. C. M. M. Stijger D.-E. Lesemann J. Th. J. Verhoeven J. W. Roenhorst 《EPPO Bulletin》2002,32(3):503-508
At the beginning of 1999, a new virus disease occurred in protected tomato crops in The Netherlands. Initial diagnostic tests revealed the presence of a potexvirus but serological tests ruled out the presence of Potato X potexvirus (PVX). Tests for other potexviruses reported from solanaceous crops provisionally identified the virus as Pepino mosaic potexvirus (PepMV). The virus was purified, and an antiserum was produced, which showed strong reactions with both the type isolate of PepMV from pepino and two other isolates from tomato. Host range and symptomatology of the pepino and tomato isolates of PepMV revealed clear differences from PVX. However, differences were also observed between the pepino and tomato isolates of PepMV. Sequence alignment of DNA fragments of 584 bp derived from the RNA polymerase cistron showed almost 95% identity with the pepino isolate, whereas the identity with PVX appeared to be < 60%. Together, these results identified PepMV as the causal agent of the new virus disease in tomato. Based on the differences from the type isolate from pepino ( Solanum muricatum ), the isolates from tomato should be considered as a distinct strain of PepMV for which the name tomato strain is proposed. 相似文献
6.
Jennifer E Graham Michael S Kent Alain Théon 《Veterinary Clinics of North America: Exotic Animal Practice》2004,7(3):757-81, vii
The majority of information on oncology therapies has been reported in humans, canine, and feline patients, and laboratory animals with experimentally induced tumors. A variety of treatments,including radiation therapy, chemotherapy, photodynamic therapy, and others have been used with exotic animals. There are many species of exotic pets, and anatomic differences, as well as husbandry and nutritional requirements, must be taken into account to provide optimal care. By providing a broad overview of therapies and considerations for treatment, this article is intended to provide the practitioner with an overview of approach and options when addressing oncology cases in exotic animals. 相似文献
7.
Goyette Jean-Olivier Cimon-Morin Jérôme Mendes Poliana Thériault Maxime Pellerin Stéphanie Poulin Monique 《Landscape Ecology》2021,36(9):2691-2706
Landscape Ecology - Human activities have led to the degradation of wetlands, impinging on their capacity to deliver essential ecosystem services to society. Wetland restoration now appears an... 相似文献
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Hofmann MA Thür B Vanzetti T Schleiss W Schmidt J Griot C 《Schweizer Archiv für Tierheilkunde》1999,141(4):185-190
In May 1998, wild boars with classical swine fever (CSF) symptoms were detected in the southern part (Canton Ticino) of Switzerland. CSF virus was isolated from the submitted samples and RT-PCR followed by direct nucleotide sequencing of the 5' non-translated region showed that this virus was identical to the isolate previously recognized in wild boars from the area of Varese (Italy). In most animals, antibodies to CSF virus were detected as well. An immediate measurement was taken by limiting the movement of pigs and identifying both risk and surveillance zones. In order not to disturb potentially infected wild boars within their habitat a complete hunting prohibition for 2 months was enforced. The different possibilities of the control of CSF outbreaks in wild boars are discussed. 相似文献
10.
A survey of Newcastle disease in Swiss laying-hen flocks using serological testing and simulation modelling 总被引:1,自引:0,他引:1
Newcastle disease (ND) is a highly contagious viral disease of birds particularly domestic poultry. Switzerland is currently declared free from ND; since vaccination is prohibited, the detection of antibodies against ND virus (NDV) results in the destruction of the respective flock (stamping-out policy). However, in 1995 and 1996, antibody-positive flocks were detected and sporadic ND outbreaks even occurred in Switzerland. Therefore, a serosurvey was done to look for evidence of NDV infections in Swiss laying-hen flocks. The survey was designed to provide 95% confidence of detecting at least one seropositive flock if the flock prevalence were 1%. Thirty blood samples from each of 260 commercial laying-hen flocks were collected during 1996 in a central poultry slaughterhouse. Sera were screened for NDV antibodies with a commercial blocking enzyme-linked immunosorbent assay (ELISA). Samples with a questionable or positive test result were retested with the same ELISA. A stochastic computer model was applied to define a cut-off number of test-positive samples to help to differentiate between true- and false-positive flocks and to estimate the true flock prevalence of infection. Four flocks were identified as NDV-seropositive and the NDV true seroprevalence among commercial laying-hen flocks in Switzerland was most likely between 1.35 and 1.55%. This indicates that Swiss laying-hen and parental flocks with more than 150 animals have been in contact with strains of NDV that cause subclinical infection in chicken, because no clinical symptoms have been observed. In this context, computer simulation was a useful technique to interpret survey results. 相似文献