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991.
Trichinella antigens: a review 总被引:13,自引:0,他引:13
This paper presents a review of the Trichinella antigens within the context of species variation. As with other parasites, Trichinella antigens can be classified according to their localisation as surface, excretory/secretory (ES) and somatic components. Surface antigens are mainly constituents of the outer cuticle although secretions from inner parts of the body wall as well as from the oesophagus can temporarily accumulate in the surface. ES antigens come mainly from the excretory granules of the stichosome, whereas somatic constitutive antigens come from the internal parts of the worms. ES products are considered very important from an immunological point of view as they are easily targeted by the immune system, whereas parasite death is required for exposure of somatic products. Some of the antigenic components have been characterised chemically. Phosphorylcholine is an important hapten that modulates the immune responses in Trichinella infections. Glycoproteins are the major components of surface and excretory/secretory products. A 43-kDa glycoprotein has been regarded as a good candidate for diagnosis and vaccination purposes. Recently some glycans have received special attention either as relevant epitopes or as parasite evasion strategies. 相似文献
992.
Several biological parameters were measured in 31 heifers naturally infected with Fasciola hepatica during one grazing season in the Belgian Ardennes. A forecast model based on daily temperature used to assess the risk of fasciolosis was fitted to this assay. Cattle were turned out to two pastures. Each pasture was divided into two plots: one was treated with calcium cyanamide and the other was left untreated. The Lymnaea truncatula snails were counted on three different occasions. The results indicated a poor molluscicide efficiency. Body weight gains, anti-Fasciola antibody levels, faecal egg counts, levels of sorbitol dehydrogenase (SDH) and gamma-glutamyl transferase (gamma GT), packed cell volumes, white blood cells and differential leucocyte counts were determined monthly. No statistically significant difference was observed between animals from the two plots regardless of the recorded data. No correlation was found between body weight gains and other biological data. The sampling date had a significant effect on the antibody responses within a same group, and on the enzymatic levels for all groups combined. The forecast results were consistent with the recorded data. Temperature was a major bioclimatic constraint on the transmission of life cycle, and risk of infection occurred mainly in late spring (May/June) and in early September. Current results might be used to issue advice on the need for flukicide treatment of cattle. The indicators of the infection considered alone were useless and it is concluded that herd diagnosis of fasciolosis may rely on the rise of specific antibody levels, possibly associated with an increase in hepatic enzyme activities. 相似文献
993.
Brand TS Johnson Q Franck F Veith W Conradie R Hough FS 《Journal of the South African Veterinary Association》1999,70(1):9-13
Increased dietary protein consumption is thought to cause calciuresis, a negative calcium balance and increased bone loss that may result in skeletal deformities and fracture. To explore this hypothesis, 40 approximately 100-day-old meat-type Merino ram lambs were fed, for 6 months, diets with an increasing crude protein (CP) content (114, 142, 171 and 190 g/kg DM) but approximately on an iso-nutrient basis with regard to metabolisable energy, calcium and phosphorus. Increased protein consumption modestly (NS) enhanced calciuresis and resulted in significant (P < or = 0.01) limb skewness. This could not, however, be ascribed to osteopaenic bones, and compared with animals consuming lower protein rations, the bone mineral density (BMD) and vertebral trabecular bone volume of animals fed high protein diets were significantly increased: the BMD of thoracic vertebrae was positively related to the CP intake (r = 0.62; P < or = 0.001). In animals consuming higher protein diets, skeletal radiology and quantitative bone histology revealed no evidence of increased bone turnover as would be expected in animals that are in negative calcium balance. No relationship existed between limb skewness and the growth rate of lambs. However, the ratio of Ca:P in the forelimb (r = -0.98), vertebrae (r = -0.72) and rib (r = -0.42) was found to be inversely correlated with increased protein intake and resulted from an increase in the phosphorus content of bone, while the amount of bone calcium was unaffected. We conclude that qualitative micro-architectural abnormalities, and not mere bone loss, may underlie the skeletal deformities induced by increased protein consumption in sheep. 相似文献
994.
Stegmann GF 《Journal of the South African Veterinary Association》1999,70(3):122-126
Xylazine, midazolam and a midazolam/ketamine combination were administered to 6 goats in a randomised 3-way block design. All goats received all treatments with at least a 7-day interval between treatments. Statistically significant (P < 0.05) changes were observed in some of the measured cardiopulmonary variables for xylazine and midazolam/ ketamine. Xylazine administration resulted in statistically significant decreases in minute volume, arterial partial pressure of oxygen, heart rate and mean arterial blood pressure. The increase in arterial partial pressure of carbon dioxide was not statistically significant. For the midazolam/ketamine combination, the decrease in tidal volume was statistically significant, but not the decrease in minute volume and increase in arterial partial pressure of carbon dioxide. The decrease in the arterial partial pressure of oxygen was also statistically significant. The mean arterial blood pressure for the combination was statistically significantly higher compared to xylazine. The changes in cardiopulmonary variables after midazolam administration were not statistically significant, such as tidal and minute volume, arterial partial pressure of oxygen and carbon dioxide. However, clinically significant effects such as hypoventilation and hypoxia were observed after its administration. The change in mean arterial blood pressure was minimal. 相似文献
995.
996.
(13Z,13'Z,3R,3'R,6'R)-Lutein has been isolated and purified from extracts of marigold flowers, fresh raw kale (Brassica oleracea var. Acephala), and human plasma and fully characterized by (1)H and (13)C NMR, UV/vis, and MS. While the concentration of (13Z, 13'Z)-lutein in kale and human plasma compared to (all-E,3R,3'R, 6'R)-lutein was found to be quite low, this compound was readily isolated by fractional crystallization of lutein from marigold extracts. Thus, the mother liquors from two consecutive crystallizations of lutein from a saponified extract of marigold flowers were enriched in (13Z,13'Z)-lutein (8.7% of total carotenoids) and employed for the isolation of this compound by HPLC. The identity of the di-Z-lutein in kale and human plasma has been established by comparison of the HPLC-UV/vis-MS profiles of the purified compounds with those of a fully characterized sample, isolated from marigolds. 3-Hydroxy-beta,epsilon-caroten-3'-one and 3'-epilutein have also been identified in extracts from marigolds. 相似文献
997.
The effect of fat content on the release of volatile aroma compounds from frankfurters has been investigated. Although the release of most n-alkanals, alcohols, ketones, and furans was little affected by changes in the fat content of frankfurters, that of monoterpene hydrocarbons, sesquiterpene hydrocarbons, terpenes containing oxygen, cyclopentenones, phenyl propanoids, and phenols was greatly increased when the fat content was decreased. Some odors were also detected more frequently in the low-fat than in the full-fat sausages. These included smoky odors, due to phenols, spicy, synthetic, and floral odors due to terpenes, and meaty, roasted odors caused by sulfur-containing heterocyclic compounds. The release of aroma compounds from frankfurters appears to be closely related to the solvation of these compounds in the lipid phase. 相似文献
998.
Length of sample storage can become significant in sensory studies due to panel fatigue limitations and samples needed for a reasonable expectation of finding significant differences. In roasted peanut sensory studies samples are stored between -10 and -23 degrees C to prevent or retard changes. Studies of up to 13 months' duration have examined stability and slow-rate sensory changes. Sweet taste was relatively stable, whereas bitter and tongue burn attributes increased slightly. Stale taste increased, suggesting lipid oxidation was taking place even at -23 degrees C. Painty attribute did not increase until stale was >3. An increase in fruity attribute was unexpected. With increases in fruity and stale attributes a decrease in roasted peanut was expected. However, storage at -23 degrees C seems to stabilize the roasted peanut lability when compared to storage at -10 degrees C. Fruity and stale interactions with roasted peanut and lability of roasted peanut were shown to be three separate and identifiable effects on roasted peanut. 相似文献
999.
1000.
OBJECTIVE: To determine changes in results of selected serum biochemical tests after a single percutaneous liver biopsy and changes in results of hematologic and selected serum biochemical tests after multiple percutaneous liver biopsies in alpacas and llamas. ANIMALS: 5 llamas and 10 alpacas. PROCEDURE: A single percutaneous liver biopsy was performed in 5 llamas and 6 alpacas. Blood samples were collected before and 1, 2, and 3 days after liver biopsy, and submitted for serum biochemical analysis. In the other 4 alpacas, liver biopsy was performed on day 0 and then weekly for 4 weeks. Blood samples were collected at the time of each biopsy, and CBC and serum biochemical analyses were performed. Attitude and appetite of all animals were evaluated daily. RESULTS: None of the animals developed clinically apparent adverse effects. A mild decrease in sorbitol dehydrogenase activity was detected in animals that underwent a single liver biopsy, and mild decreases in plasma protein and albumin concentrations were detected in animals that underwent multiple biopsies. Other significant changes were not detected. CONCLUSIONS: Results of this study suggest that liver biopsy is safe in healthy llamas and alpacas and that, if necessary, multiple weekly liver biopsies can be performed safely in healthy alpacas. 相似文献