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21.
Interferon induction in bovine and feline monolayer cultures by four bluetongue virus serotypes. 总被引:2,自引:0,他引:2 下载免费PDF全文
The interferon inducing ability of bluetongue viruses was studied in bovine and feline monolayer cultures inoculated with each of four bluetongue virus serotypes. Interferon was assayed by a plaque reduction method in monolayer cultures with vesicular stomatitis virus as challenge virus. Interferon was produced by bovine turbinate, Georgia bovine kidney, and Crandell feline kidney monolayer cultures in response to bluetongue virus serotypes 10, 11, 13 and 17. The antiviral substances produced by the bluetongue virus infected cultures had properties of interferon. 相似文献
22.
Berry SD Weber Nielsen MS Sejrsen K Pearson RE Boyle PL Akers RM 《Domestic animal endocrinology》2003,25(3):245-253
The objectives of the experiment were (1) to determine whether MAC-T cells would accurately mimic the previously observed proliferative responses of primary mammary epithelial cells (MEC) to mammary tissue extracts from high and low-fed heifers and (2) to determine whether mammary tissue extracts from ovariectomized (OVX) heifers would have lower mitogenic activity than intact controls. Addition of mammary tissue extracts to cell culture media of MAC-T cells plated on plastic or collagen-coated plastic to a range of concentrations between 1 and 8% resulted in dose-dependent increases in cell proliferation. Furthermore, mammary tissue extracts from low-fed prepubertal heifers aged 9 months, stimulated significantly more proliferation of MAC-T cells, as measured by 3H-thymidine incorporation into DNA than mammary tissue extracts from high-fed heifers (40.6 cpm x 10(3) per well versus 21.9+/-1.8 cpm x 10(3) per well). These observations suggested that MAC-T cells would be a suitable alternative to primary MECs for measuring the mitogenic activity of mammary tissue extracts. Conversely, no difference was observed in the mitogenic activity of mammary tissue extracts from OVX or control heifers. Possibly, MAC-T cells provide a good model for nutrition- but not ovarian-induced changes in mammary growth. Alternatively, that reduction of in vivo mammary development following OVX did not result in reduced mitogenic activity of the mammary tissue extracts emphasizes that heifer mammary development is the result of complex interactions between local growth factors and systemic hormones. 相似文献
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Lobetti R Dvir E Pearson J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(1):63-68
This study compared the sensitivity of ECG and cardiac troponins to predict cardiac histopathological changes, clinical severity, and survival in canine babesiosis. One control group (n = 9) and 4 groups of dogs with mild uncomplicated babesiosis (n = 8), severe uncomplicated babesiosis (n = 9), complicated babesiosis (n = 8), and babesiosis and concurrent immune-mediated hemolytic anemia (IMHA) (n = 9) were studied. A 1-minute lead II ECG was recorded, and cardiac troponin I (cTnI) and T (cTnT) concentrations in plasma were measured. cTnI concentrations were significantly higher in the complicated (mean, 9.9; SE, +/-5.76) and concurrent IMHA (mean, 6.53; SE, +/-4.32) groups and in the 3 dogs that died of the disease (mean, 22.17; SE, +/-12.85) than in the control dogs (concentration below detection limit of test, -0.3 ng/mL). The 3 nonsurvivors had the most severe cardiac histopathological changes, but no arrhythmia and minimal other ECG changes. Dogs with babesiosis developed a variety of ECG abnormalities, but the abnormalities were not associated with disease severity, outcome, or plasma cardiac troponin concentrations. The exception was the presence of ventricular premature complexes (VPCs), which were associated with high cardiac troponin concentrations. This study showed an association between cTnI concentration and histological changes, clinical severity, and survival and no correlation between ECG abnormalities and histological changes or biochemical evidence of myocardial damage as reflected by cTnI concentrations. From this study, it was concluded that the analysis of plasma cTnI is a feasible and sensitive test and is superior to cTnT in diagnosing cardiac involvement in dogs with babesiosis. 相似文献
24.
OBJECTIVE: To determine clinical, clinicopathologic, and postmortem abnormalities in New World camelids with pancreatic necrosis. DESIGN: Retrospective study. ANIMALS: 10 llamas and 1 alpaca. PROCEDURES: Medical records of animals in which a diagnosis of pancreatic necrosis had been made on the basis of histologic examination of necropsy specimens or on the basis of clinical signs and results of clinicopathologic testing were reviewed. RESULTS: The initial owner complaint varied, and various other conditions were diagnosed. Clinical and clinicopathologic abnormalities were vague. Amylase activity was higher in abdominal fluid than in serum in 5 of 7 animals, and lipase activity was higher in abdominal fluid than in serum in all 7. Four animals survived, and 7 died or were euthanatized. Only 1 of the animals that died had marked inflammation of the pancreatic parenchyma. All 7 had necrosis and saponification of fat in and surrounding the pancreas. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that pancreatic necrosis may develop in New World camelids, but clinical signs are vague, and the condition may easily be confused with other diseases. The only laboratory test that appeared to be helpful in the antemortem diagnosis of pancreatic necrosis was comparison of amylase and lipase activities in abdominal fluid and serum. 相似文献
25.
Wendy Pearson Semir Omar Andrew F. Clarke 《Canadian journal of veterinary research》2007,71(3):213-217
The purpose of this study was to determine if ginseng fed at low levels enhances a horse's antibody response to vaccination against Equid herpesvirus 1 (EHV-1). For 28 d, 5 horses received ground, powdered ginseng (35 mg/kg body weight, 1.7 mg/kg total ginsenosides) in molasses as a carrier, and 5 received molasses only. On day 14, each horse was vaccinated against EHV-1. The time course of the antibody response to vaccination was significantly altered in the horses receiving ginseng, a clinically relevant increase in antibody titer being observed by postvaccination day 2 compared with day 6 in the control horses. The horses receiving ginseng also had a significant decrease in serum levels of sodium and a significant increase in serum levels of potassium. No adverse effects of ginseng treatment were identified by hematologic and blood biochemistry profiles. Thus, low-dose dietary supplementation with ginseng in healthy horses may be a useful adjunct to vaccination. 相似文献
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We evaluated whether new information could be drawn from additional data collection and unconventional statistical analyses of an on-farm trial. First, we compared a conventional sampling method using a biomass estimate of weed abundance to repeated visual assessment of the percentage ground cover of weeds. The biomass was sampled once after the treatment, whereas the ground cover was repeatedly sampled once before weed control plus several occasions after weed control. Second, we contrasted the outcomes from analysis of variance ( anova ), taking samples from a single point in time with repeated measures (rm) anova and a multivariate method. As the outcomes and conclusions drawn were relatively similar, we conclude that the ground cover estimate of weed abundance was as reliable as the biomass estimate. The rm anova enabled us to follow the temporal trend in response to treatments in the most abundant species, including possible initial differences. Multivariate analysis went even further, by clearly displaying species-wise responses and treatment selectivity. 相似文献
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In the past, pressing fluids from ground plant matter has typically been accomplished with a hand press. Fluids must be separated from dry matter as part of the methodology for various applications in plant species including latex quantification. This article describes the design and construction of a hydraulic press used for extracting fluids from plant tissue samples, the accompanying press plates, sieve vessels, and collection pan, and the process we use for pressing plant fluids from sunflower (Helianthus annuus) homogenate. The overall height of the press is 205.7 cm (81 in.) and the width is 94.0 cm (37 in.). We have used the press for several years and have not identified any flaws in its design and performance. While designed and constructed for use in latex extraction we envision the press and associated press plates, sieve vessels, and collection pan could be used in a variety of other applications. 相似文献