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991.
The saponin adjuvant Quil A was investigated in trivalent vaccination against foot-and-mouth disease with a concentrated vaccine based on BHK suspension cell virus of the serotypes O, A and G. The activity in cattle was estimated on the basis of seroneutra-lizing antibodies. Five and 10 ml doses with or without 1 mg of Quil A were each injected into 6 animals. Seroneutralizing antibodies were estimated at regular intervals during a period of 29 weeks. The activity in guinea pigs was estimated by experimental challenge. One ml doses of serial 4-fold dilutions of the vaccine with or without 50 µg of Quil A were injected into 24 groups of 20 guinea pigs. Challenge was given 3 weeks after vaccination.It was concluded that Quil A showed adjuvant activity in cattle and guinea pigs with all the serotypes used in the trivalent vaccination. 相似文献
992.
To study bile acid metabolism in the pig, indwelling catheters were surgically placed in the hepatic portal vein and the anterior vena cava of 12-17 kg crossbred pigs. The pigs were fed ad libitum for one hr at 0800 and 1600 hrs daily. Two weeks after the surgery, 50 microCi of 24[14C] chenodeoxycholic acid were infused into the hepatic portal vein. The radioactivity in plasma from the two veins was monitored hourly for six hrs following each of six consecutive meals over a 3-day period. Fecal and urine radioactivity were determined for 14 days. It was found that the peak levels of radioactivity in the plasma of both veins were reached within two hrs post-feeding. The biological half-life of chenodeoxycholic acid was determined to be 6.4 days. 相似文献
993.
G. T. Woods A. H. Jensen Jennifer Gossling H. E. Rhoades W. F. Nickelson 《Canadian journal of veterinary research》1972,36(1):49-54
Antimicrobial agents were added to the feed of swine for three weeks to determine the interrelationships of potentially pathogenic agents in the nasal tract, turbinate atrophy and weight gains.
Bordetella bronchiseptica was not isolated from the groups fed the combination of chlortetracycline, penicillin and sulfamethazine. B. bronchiseptica was found in some pigs after the feeding trail, but this organism was not significantly associated with turbinate atrophy at the time of slaughter.
Mycoplasma hyorhinis was not found in the nasal passages of the pigs that received feed containing high concentration chlortetracycline but was found in pigs that received other diets. Hemophilus suis was not significantly reduced by any of the treatments used.
The organisms studied in the pigs were not isolated from the personnel handling the pigs.
相似文献994.
The Ahb/Ahb homozygous and the Ahb/Ahd heterozygous inbred mouse strains from the (C57BL/6)(DBA/2)F1 X DBA/2 backcross are genetically responsive to 3-methylcholanthrene. They both also develop, within 6 hours after a large intraperitoneal dose of acetaminophen, an irreversible opacity in the anterior portion of the lens. Such cataract formation does not occur in similarly treated nonresponsive inbred strains or nonresponsive Ahd/Ahd individuals from the same backcross. Differences in acetaminophen metabolism and toxicity are associated with the Ah locus in the mouse, and differences in heritability at the Ah locus exist in the human. Our ophthalmologic findings may be important clinically to certain patients receiving either a single large overdose of this drug or high doses over a long period. 相似文献
995.
The vitamin E distribution in serum, liver, adipose and muscle tissues in the pig during depletion and repletion 总被引:1,自引:0,他引:1
This study was designed to examine the storage capacity for vitamin E in liver, adipose tissue and skeletal muscle of growing pigs during a period of supplementation and of depletion. Therefore, biopsy specimens of these tissues and samples of serum were frequently taken from 7 pigs throughout the experimental period. After a 7-week period on a diet highly supplemented with vitamin E (405 mg/kg), a significant increase (p less than 0.001) in the concentration of this vitamin was observed in all tissues sampled. The highest level (102.9 +/- 26.2 mg/kg) was observed in the liver. After 2 days of depletion the concentration of vitamin E in the liver had fallen by 80%, whereas the concentration in the fat and muscle remained unchanged during 1 week of depletion. The serum vitamin E value rose significantly (p less than 0.001) after 1 week on the supplemented diet and then remained at about 7 mg/l throughout the supplementation period and decreased (p less than 0.001) after 2 days on a nonsupplemented diet. Generally, the serum vitamin E levels among growing pigs are between 2 and 3 mg/l. The results show that the serum and liver values were correlated when the serum level was within this range. Moreover, it is clearly demonstrated that the concentrations of vitamin E in serum and liver reflect the immediate nutritional status of the animal, whereas the vitamin concentrations in adipose and skeletal muscle tissue reflect its long-term nutritional history. 相似文献
996.
J G Cunningham D Haidukewych H A Jensen 《Journal of the American Veterinary Medical Association》1983,182(10):1091-1094
Fifteen dogs with idiopathic epilepsy were included in a 9-month clinical trial to determine the therapeutic serum concentrations of primidone and its active metabolites, phenobarbital and phenylethylmalonamide. Dogs with a seizure frequency greater than 1/mo or with a record of multiple seizures greater than 1/day were chosen for the study. Each dog was given primidone 3 times daily at dosages intended to maximize seizure control and to minimize undesired side effects. Maintenance period blood samples were taken from fasted dogs 7 hours after dosing in the 3rd, 5th, 7th, and 9th months of the trial to determine therapeutic serum concentrations of primidone and its metabolites. Two blood samples also were taken from all dogs 7 hours after dosing, during an enforced drowsy period, to establish upper limits of desirable serum concentrations of the drug. Seizure frequencies during the trial were controlled in 13 dogs, 7 of which had no seizures during the 9-month trial. The mean percentage reduction in seizure frequency from pretrial frequency was 85%. Two dogs appeared refractory to primidone therapy. Serum phenobarbital was the best metabolite of primidone to use to assess therapeutic serum concentrations. The therapeutic antiepileptic serum concentration of phenobarbital was found to be between 25 and 40 micrograms/ml of serum. Serum phenobarbital concentrations greater than 40 micrograms/ml resulted in side effects in most dogs. 相似文献
997.
998.
H E Jensen H V Krogh H Sch?nheyder 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(1):33-40
The agreement between three diagnostic methods (mycology, morphology, and immunofluorescence staining) was compared two by two in elucidating the aetiological diagnosis in 52 cases of bovine mycotic abortion. Agreement between the three methods was expressed by the kappa coefficient (kappa), and ranked as follows: mycology and immunofluorescence staining (kappa = 0.48); morphology and immunofluorescence staining (kappa = 0.40); mycology and morphology (kappa = 0.28). A. fumigatus was confirmed to be the main cause of bovine mycotic abortion with members of the zygomycetes (order Mucorales) being the second most important group. In two aborted placentas a Candida species was found to be the cause of mycotic placentitis. 相似文献
999.
1000.