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141.
There is only limited information on sheep interferon available. Recent publications have reported on: 1. an interferon (IFN) alpha subtype, which is secreted by the fetal trophectoderm into the lumen of the uterus between the 10th and 21st day of gestation. It was therefore named ovine trophoblast protein (oTP-1), and is responsible for signalling pregnancy to the ewe via high affinity receptors in the endometrium. It is thought that oTP-1 acts by directly influencing prostaglandin metabolism. 2. the role of lentivirus-induced interferon (LV-IFN) in the pathogenesis of Maedi/Visna. The results indicate that LV-IFN limits viral replication and therefore contributes to virus persistence and is also responsible for a chronic inflammatory process. 3. the mitogen- or antigen-dependent induction of ovine interferon gamma (IFN gamma) and its characterization. 相似文献
142.
An outbreak of infectious anaemia in 46 broiler flocks due to chicken anaemia agent (CAA) is described. The vertically acquired infection led to increased mortality (3.6-19.8%) in 16 to 24 day-old broiler chickens. At necropsy severe atrophy of thymus and anaemia with pale bone marrow was observed. The histologic findings were depletion of cortical thymocytes and of hematopoietic cells in the bone marrow. The CAA was isolated from 15 of 35 examined broiler flocks. 相似文献
143.
Benny J. Woody DVM MS Michael J. Murphy DVM PhD AIlen C. Ray PhD Robert A. Green DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(1):23-28
The clinical signs and laboratory changes of brodifacoum (BDF) intoxicated dogs and their response to vitamin K1 treatment were examined. Brodifacoum, a second-generation anticoagulant rodenticide, was fed to four dogs for 3 consecutive days producing a cumulative dose of 1.1 mg BDF/kg body weight. Clinical observations of the animals were made daily throughout the study. Monitored laboratory parameters included: one-stage prothrombin time (OSPT), activated partial thromboplastin time (APTT), activated coagulation time (ACT), complete blood counts, thrombocyte counts, and serum chemistry values. Response to vitamin K1 therapy was evaluated clinically and by laboratory tests. Serum BDF concentrations were monitored. Inappetence and hemorrhagic tendencies were exhibited by day 5 postrodenticide exposure. One-stage prothrombin time, APTT, and ACT were 25% greater than time zero values at 24, 24, and 72 hours postdosing, respectively. All laboratory parameters returned to normal within 48 hours of initiating vitamin K1 therapy (0.83 mg/kg orally, TID for 5 days). Serum brodifacoum concentrations were highest (1065-1215 ng/mL) during the 3 days after BDF dosing and were detectable (3.0-7.5 ng/mL) until day 24 postexposure. A mean BDF elimination half-life of 6 +/- 4 days was observed. 相似文献
144.
Long‐term experiments are a classical case of repeated measurements. Traits are measured on the same experimental unit over many years so that correlations arise between the observations made on the same plot in consecutive years. This paper describes the analysis of a three‐crop‐rotation long‐term experiment. We analysed the yields of the crops and the organic carbon content in the topsoil over 30 consecutive years. Several variance–covariance approaches are discussed and the trait‐specific best fit is interpreted. Mixed models are used to describe the structure of the experiment. Both yields and soil organic carbon show a more or less pronounced variance heterogeneity. Especially for yields, the heterogeneity of cycles and years is dominant. The consideration of correlations results in a better model fit in all cases. 相似文献
145.
Gore Tex organoids and genetic drugs 总被引:2,自引:0,他引:2
B J Culliton 《Science (New York, N.Y.)》1989,246(4931):747-749
146.
J B Herrick 《Veterinary Clinics of North America: Food Animal Practice》1989,5(3):457-469
Marketing to veterinarians is the process of synchronizing the business aspects of his or her goods and services so that they are understood and desired by animal owners. The basic components of a successful marketing program are in four categories: the individual, the situation, the needs, and the implementation. Each category is important and all are interrelated; however, the implementation of a program should not begin until a self-analysis has been done and the situation and its needs are thoroughly researched. Programs that have been used by successful practitioners can be copied. No program can be effective unless the economic status of the client's enterprise is known and understood. 相似文献
147.
An experiment comprising 19 German Landrace sows was established to evaluate the effect of folic acid supplements (10 mg/kg concentrate) on homocysteine and folic acid concentration in plasma and serum, respectively, of highly pregnant sows as compared to an unsupplemented control (basal diet contained 0.62 mg folic acid/kg concentrate). Blood samples were taken between day 75 and 110 of gestation for homocysteine analysis and on day 100 of gestation for folic acid determination. Due to the folic acid supplements serum folic acid concentration increased significantly (104 nmol/l in controls and 140 nmol/l in supplemented sows). In contrast, homocysteine concentration in the plasma was not significantly influenced by folic acid supplements (16.6 mumol/l in controls and 15.2 mumol/l in supplemented sows). Further investigations seem to be necessary to clarify the physiology of homocysteine metabolism in swine. 相似文献
148.
S Cavirani C S Cabassi G Donofrio B De Iaco S Taddei C F Flammini 《Preventive veterinary medicine》2001,50(1-2):145-151
Although the seroprevalence of Chlamydia psittaci is widespread in Italian dairy herds, its role in inducing genital disorders has not been elucidated. We therefore set up a case-control study to compare seroprevalence to C. psittaci in an aborted-cow population and in a randomly selected control group in the province of Parma (the Po Valley of northern Italy). The true seroprevalence (45%) in aborted cows was significantly higher than that in the control group (24%) (adjusted odds ratio=2.53). 相似文献
149.
Taenia saginata cyst fluid was examined for host proteins; IgG1 and IgG2 as well as haemolytic complement activity were detected. Polyacrylamide gel electrophoresis revealed differences in proteinograms among the samples taken from 1-, 4-, and 10-month old cysts. Fluid from older cysts had fewer protein components and showed a weaker antigenic reaction with sera of bovines infected with T. saginata than that of younger cysts. The roles of antibody and complement in initiating degeneration of the parasite are discussed. 相似文献
150.
A study was conducted to determine if four surfactants can induce increased weight gain in the mouse. Basic-H, Triton X-100, Amway All Purpose Adjuvant and X-77 were put in water and fed to various groups of ICR 21 day old female mice for a period of 43 days. All the mice were clinically normal throughout the study period. Pathological examination of a random sample of the mice revealed no gross pathological changes. Similarly, histopathological examination of the lungs, livers and intestines did not reveal any visible lesions. Basic-H and Amway surfactants induced weight gain, though not significantly, better at 0.1% (V/V) concentration while X-77 and Triton X-100 induced weight gain better at 0.4% (V/V) concentration. Overall results show that none of the surfactants tested induced significant weight gain. 相似文献