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991.
Resistance to fascioliasis--a review   总被引:2,自引:0,他引:2  
Attempts to actively stimulate or passively transfer resistance to Fasciola hepatica or F. gigantica in various laboratory and farm animals including mice, rats, rabbits, sheep, goats and cattle have been reviewed. These attempts comprised sensitization by primary homologous or heterologous normal or irradiated infections per os, sensitization by subcutaneous, intramuscular or intraperitoneal implantation with the various fluke stages, sensitization by somatic extracts or metabolic products of mature or immature flukes and passive transfer of resistance by immune serum or sensitized lymphocytes.  相似文献   
992.
The results obtained indicate, that catfish peripheral blood lymphocytes recognize and respond to human IL-1. The second part of this report is dealing with a substance produced by carp epidermal cells with functional similarities to mammalian IL-1.  相似文献   
993.
Effect of liquid test meal volume on gastric emptying was investigated in healthy nonoperated dogs fed meal sizes of 6.6 to 110 ml/kg of body weight. For meals less than or equal to 66 ml/kg, the amount of test meal emptied from the stomach in 30 minutes vs meal size could be described as following a linear, exponential, or square root pattern. Deviation from these patterns was seen with test meals of 77, 88, and 110 ml/kg. A mean +/- SEM maximum of 0.99 +/- 0.06 ml/kg/min of liquid test meal was emptied from the stomach of dogs fed test meals of 77, 88, and 110 ml/kg. Massive gastric distension induced in dogs during this study did not alter gastric emptying of the liquid test meal.  相似文献   
994.
995.
Laying hens when transferred from accommodation at an ambient temperature (Ta) of 30 degrees C to one of 20 degrees C failed to acclimatise to intermittent heat stress (Ta 38 degrees C) commencing one day after the transfer. After 21 d of intermittent exposure to 38 degrees C these hens showed little or no increase in heat tolerance, whereas hens living constantly at either Ta 20 degrees C or 30 degrees C acclimatised normally. The failure to acclimatise was also observed when hens were transferred from Ta 30 degrees C to 5 degrees C but not when transferred from Ta 5 degrees C to 30 degrees C. The failure to acclimatise following transfer from a warm to a cool environment was accompanied by an increase in food intake; if food intake was not allowed to increase the hens acclimatised normally to heat stress.  相似文献   
996.
Survival to maturity and age at first calving were studied in heifer calves from 34 randomly selected Holstein dairy farms in southwestern Ontario. Calves were divided into cohorts on the basis of treatment for pneumonia, scours, other diseases, or no treatments, during the first 90 days of life. An effect of pneumonia and scours together, over and above the effects of each disease alone, was assessed by means on an interaction term in the statistical analyses. Heifers which had been treated for pneumonia during the first three months of life were 2.5 times more likely to die after 90 days of age than heifers which had not been treated for pneumonia, after controlling for the farm effect. Heifers with a calfhood history of being treated for scours were 2.5 times more likely to be sold for dairy purposes than other calves. Heifers which had been treated for scours were 2.9 times more likely to calve after 900 days of age than other heifers, after controlling for the farm effect.  相似文献   
997.
Pharmacokinetic adjustment of gentamicin dosing in horses with sepsis   总被引:1,自引:0,他引:1  
Serum gentamicin concentrations were measured and pharmacokinetic values were calculated for 12 equine patients receiving parenteral gentamicin therapy. Horses were selected for monitoring of gentamicin pharmacokinetics if they met several criteria of high risk for gentamicin-induced toxicosis. Two blood samples were obtained, one immediately before gentamicin dosing and one at 1 hour after dosing. Gentamicin serum concentrations were analyzed and dosage adjustments were made on the basis of calculated one-compartment pharmacokinetic values. Nine of the 12 horses required dosage adjustment to optimize therapeutic concentrations. Even for horses for which there was no evidence of decreased renal function, variation in the disposition of gentamicin was substantial. Because of the larger volume of distribution in foals, an initial dosage of 3 mg/kg every 12 hours was found to best approximate target concentrations. Therefore, published standard dosages were a poor means of achieving desired peak and trough concentrations in many animals. Seemingly, for optimal treatment of horses with sepsis, gentamicin dosage adjustments based on the patient's pharmacokinetic values is required.  相似文献   
998.
Serum and peritoneal fluid concentrations of metronidazole were determined in 6 healthy adult horses given the drug (25 mg/kg) by IV or oral routes. The disposition of metronidazole in horses given the drug by the IV route conformed to a 2-compartment model with a distribution half-life of 0.16 hours, an elimination half-life of 2.9 hours, and a body clearance of 0.40 +/- 0.05 L/kg/hr. The oral absorption half-life was 0.40 hours, and the bioavailability, 85.0 +/- 18.6%. Peritoneal fluid concentrations were approximately equal to serum concentrations at all times, regardless of the route of administration. On the basis of reported minimal inhibitory concentrations for anaerobic bacteria, a dosage of 15 to 25 mg/kg given orally 4 times daily was recommended.  相似文献   
999.
Gray-scale ultrasonography was utilized in addition to radiography in the diagnosis of reproductive disease in 18 bitches. In 72% of the cases, ultrasonography was considered diagnostic because it revealed information on organ architecture, relationships of radiographically silhouetting soft tissue structures, and fetal viability that was unobtainable by radiography alone. In the remainder of the cases, ultrasonography was contributory to the diagnostic process by supporting the clinical and radiographic diagnoses. The benefits of ultrasonography are discussed, as is the ultrasonographic appearance of a variety of reproductive tract diseases.  相似文献   
1000.
Interrelationships between N-acetyl-beta-D-glucosaminidase (indicating cellular damage) and antitrypsin (indicating increased permeability between the blood and milk compartments) were evaluated in 1,411 quarter-milk samples collected during routine herd surveys. N-Acetyl-beta-D-glucosaminidase was antitrypsin, whereas, in more severe mastitis, antitrypsin had a more constant deflection. The sensitivity of both determinants was associated with the virulence of bacteria. Production of bacterial hemolytic toxins was associated with a significant increase in both determinants. Penicillinase production by staphylococci was associated with selective increases of antitrypsin.  相似文献   
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