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121.
D. Kelley C. Lester S. Shaw A. de Laforcade C.R.L. Webster 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(4):1053-1062
Background
Given the liver''s pivotal role in hemostasis and fibrinolysis, the coagulopathy accompanying hepatic disease is complex.Hypothesis/Objectives
To prospectively evaluate kaolin‐activated thromboelastography (TEG) in dogs with acute liver disease (ALD) and compare with plasma‐based coagulation tests.Animals
Twenty‐one dogs with a diagnosis of ALD based on recent onset of clinical signs accompanied by increases in serum bilirubin concentration and alanine aminotransferase activity.Methods
Clinical presentation, CBC, serum biochemistry, platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), and TEG analysis were evaluated in 21 dogs with a subset also having fibrinogen, antithrombin (AT) activity, protein C (PC) activity, d‐dimers, and von Willebrand''s factor (vWF) activity analyzed. A PT >1.5 times the upper limit of normal defined acute liver failure (ALF).Results
Dogs with ALD had mean increases in R, K, LY30, PT, aPTT, and vWF activity, and decreases in angle, maximal amplitude (MA), G, AT activity, and PC activity. The TEG results defined dogs as hypocoagulable (11/21), normocoagulable (8/21), or hypercoagulable (2/21). Increases in LY30 defined 8/21 dogs as hyperfibrinolytic. Hypocoagulable and hyperfibrinolytic dogs had lower fibrinogen and PC activity than dogs without these abnormalities. Overall, ALF dogs had greater increases in K and LY30, and decreases in MA, G, and PC activity than dogs with less severe hepatic impairment. Results for MA and LY30 were positively correlated with serum bilirubin concentration and white blood cell count, and negatively correlated with serum cholesterol concentration.Conclusions and Clinical Importance
ALD dogs have a range of coagulation abnormalities that trend toward hypocoagulability and hyperfibrinolysis as functional impairment occurs. 相似文献122.
David J. Wise Terrence E. Greenway Todd S. Byars Matt J. Griffin Lester H. Khoo 《Journal of aquatic animal health》2015,27(2):135-143
Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are typically administered by immersion when fry are transferred from the hatchery to rearing ponds. While this approach is a practical method of mass delivery, this strategy administers vaccines to very young fish, which lack a fully developed immune system. To circumvent this limitation, an oral vaccination strategy was evaluated as a means of immunizing catfish at the fingerling stage of production, when fish possess a more complete immune arsenal. A virulent E. ictaluri isolate (S97-773) was attenuated by successive passage on media containing increasing concentrations of rifamycin. In laboratory trials, cultured vaccine was diluted and mixed with feed (100 mL diluted vaccine/454 g feed). This mixture was then fed to Channel Catfish Ictalurus punctatus fingerlings. Two separate dilutions of cultured vaccine (1:10 and 1:100) were used to create the vaccine–feed mixture, equating to estimated doses of 5 × 107 and 5 × 106 CFU/g of feed, respectively. After 30 d, catfish were exposed by immersion (1 × 106 CFU/mL) to the virulent parental strain of E. ictaluri. The target dose (1:100 dilution, ~5 × 106 CFU/g of feed) offered exceptional protection (relative percent survival = 82.6–100%). In addition, negligible deaths occurred in fish vaccinated at 10 times the target dose (1:10 dilution, ~5 × 107 CFU/g of feed). In pond trials, antibody production increased 18-fold in orally vaccinated fish. When compared with nonvaccinated controls, vaccination significantly improved survival, feed fed, feed conversion, biomass produced, and total harvest. This research demonstrates Channel Catfish can be successfully immunized in a commercial setting against E. ictaluri with a single dose of an orally delivered, live attenuated, E. ictaluri vaccine.
Received July 31, 2014; accepted March 2, 2015 相似文献
123.
The mane of the African lion (Panthera leo) is a highly variable trait that reflects male condition and ambient temperature. We examined the consequences of this variation in a long-term study of lions in the Serengeti National Park, Tanzania. Mane darkness indicates nutrition and testosterone and influences both female choice and male-male competition. Mane length signals fighting success and only appears to influence male-male assessment. Dark-maned males enjoy longer reproductive life-spans and higher offspring survival, but they suffer higher surface temperatures, abnormal sperm, and lower food intake during hot months of the year. Maned males are hotter than females, and males have lighter and/or shorter manes in hotter seasons, years, and habitats. This phenotypic plasticity suggests that the mane will respond to forecasted increases in ambient temperature. 相似文献
124.
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126.
Lester W. Sinton Margaret L. Mackenzie Naveena Karki Rod L. Dann Liping Pang Murray E. Close 《Water, air, and soil pollution》2012,223(5):2347-2360
The relative transport and attenuation of bacteria, bacteriophages, and bromide was determined in a 5?m long?×?0.3?m diameter column of saturated, heterogeneous gravel. The average pore velocity (V), longitudinal dispersivity (?? x ), and total removal rate (??) were derived from the breakthrough curves at 1, 3, and 5?m, at a flow rate of 24.8?L?h?1. The experiments largely confirmed the differences in transport and attenuation patterns among bacteria, phages, and bromide, and between colloid-associated and ??free?? microorganisms, previously observed in a study using homogeneous pea gravel. Cultured Escherichia coli J6-2 cells were transported faster than phage MS2 and bromide, consistent with velocity enhancement of the larger particles. The evidence for velocity enhancement of phage MS2 compared with bromide was less conclusive, with some evidence of retardation of the phage as a result of adsorption?Cdesorption processes in the finer media. On average, phage in sewage and adsorbed to kaolin particles were transported faster than free phage, suggesting that most sewage phage are adsorbed to colloids. However, average velocities of cultured and sewage E. coli differed far less, suggesting that most E. coli in sewage exist as individual (non colloid-associated) cells. There was no conclusive evidence that the wider pore size range in the heterogeneous mixture compared with pea gravel increased velocity enhancement effects. Removal rates of free phage were far higher than in the pea gravel, and were attributed to adsorption in the finer materials. Equivalent increases in removal of cultured and sewage E. coli and colloid-associated phage were attributed to straining in finer materials and settling in quiescent zones. Inactivation (??) rates (determined in the pea gravel study) indicated little contribution to removal of either free or attached microorganisms. The results showed the importance of association with colloids in determining the relative transport of bacteria and viruses in alluvial gravels. 相似文献
127.
Acevedo AM Díaz de Arce H Brandão PE Colas M Oliveira S Pérez LJ 《Research in veterinary science》2012,93(2):1046-1049
The emergence of new infectious bronchitis virus (IBV) genotypes or serotypes along with the poor cross-protection observed among IBV serotypes have complicated the avian infectious bronchitis (IB) control programs in different geographic regions. In Cuba, the lack of genetic information regarding IBV and the increasing epidemiological importance of this virus in Cuban chicken flocks demand further characterization of IBV isolates. In the present work, studies of genetic diversity and phylogenetic relationships among recent IBV isolates from Cuban chicken flocks showing respiratory disorders were performed. Two putative genotypes genetically different to the Massachusetts genotype H120 strain used in the Cuban vaccination program were found in the flocks assessed. In addition, a potential nephropathogenic IBV isolate was found by first time in Cuba. 相似文献
128.
129.
Lester GE 《Journal of agricultural and food chemistry》2008,56(10):3694-3698
Orange-fleshed, non-netted honeydew ( Cucumis melo L.) is a relatively new melon in the marketplace and has shown a lot of potential as an alternative to netted muskmelons (cantaloupes), which are often prone to surface contamination by enteric bacteria. Orange-fleshed honeydew is a cross between orange-fleshed cantaloupe and non-netted, green-fleshed honeydew. This glasshouse study investigated the nutritional profile (phytonutrient and sugar contents) in different tissues of mature orange-fleshed honeydew melon fruit. The equatorial mesocarp of ripe fruit was segmented into hypodermal (subpeel), outer, middle, and inner (near the seed cavity) tissues and then assayed for total sugars, mineral nutrients, phytonutrients, total proteins, and enzymatic antioxidant activities. The concentrations of soluble solids, sucrose, total sugars, beta-carotene, and 5-methyltetrahydrofolic acid increased in an inward direction from the subpeel mesocarp tissues toward the seed cavity. The activities of ascorbate peroxidase, catalase, and superoxide dismutase also increased in an inward direction. The concentrations of calcium, iron, magnesium, manganese, and sodium all decreased in the inward direction. When expressed on a dry weight basis, the concentrations of ascorbic acid, boron, copper, fructose, glucose, phosphorus, potassium, and zinc were higher in the subpeel region compared to the inner mesocarp tissues, but the reverse was true when data were expressed on a fresh weight basis. These data reveal that there is considerable variation in sugars, minerals, and phytonutrients across the mesocarp regions and that expressing the data on a fresh or dry weight basis can alter interpretations of the nutritional significance and health benefits of fruit. The data also confirm that orange-fleshed honeydew melon can be a rich source of many human health-related nutrients. 相似文献
130.
Nola V. Lester BVMS Gregory D. Roberts DVM MS Susan M. Newell DVM MS John P. Graham MVB MSC Christine S. Hartless M.Stat. 《Veterinary radiology & ultrasound》1999,40(5):465-471
Barium impregnated polyethylene spheres (BIPS) are radiopaque markers used for investigation of a variety of gastrointestinal disorders. One proposed use of the small (1.5 mm) marker is quantitative assessment of solid-phase gastric emptying, which may offer a simple, inexpensive alternative to nuclear medicine studies. In this study the rate and pattern of gastric emptying of a radiolabeled meal containing 30 small BIPS was evaluated in normal dogs by simultaneous comparison of the radiopaque marker method and a scintigraphic method. Serial scintigraphic images and radiographs were obtained for 8 hours or until 95% of the markers had left the stomach. Emptying curves were constructed and statistical analyses performed. There were significant differences in gastric emptying times and lag phase characteristics between the BIPS and scintigraphic studies. These results indicate that in normal dogs there are differences in both the rate and the pattern of solid-phase gastric emptying of a radiolabeled meal as assessed by scintigraphy and the gastric emptying of small BIPS. 相似文献