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81.
82.
The effect of dose and line on immunisation of cattle with lymphoblastoid cells infected with Theileria annulata 总被引:1,自引:0,他引:1
H Ouhelli E A Innes C G Brown A R Walker S P Simpson R L Spooner 《Veterinary parasitology》1989,31(3-4):217-228
Thirty-one Friesian calves in Morocco susceptible to tropical theileriosis were protected against a lethal sporozoite challenge by prior infection with lymphoblastoid cell lines infected and transformed in vitro by a Moroccan stock of Theileria annulata. The challenge infection of cryopreserved sporozoites killed all four susceptible control calves within 20 days. Four schizont-infected cell cultures at Passage 3 were inoculated at four different doses, 10(8), 10(6), 10(4) and 10(2), into pairs of calves. The recipient animals showed great variation in severity of disease symptoms, which did not show a linear correlation with the cell dose inoculated. The most severe disease symptoms were recorded, prior to challenge, in the 10(2) cell dose recipients; one animal died of acute theileriosis and another had to be treated. One of the four cell lines used was more virulent than the other three. Two years after the completion of this experiment, immunised animals have shown normal productivity traits. 相似文献
83.
Significance of ureaplasma infection in infertility of turkeys 总被引:4,自引:0,他引:4
L Stipkovits P A Brown R Glavits J Zajer 《Archiv fuer experimentelle veterinaermedizin》1986,40(1):103-104
84.
The use of polyester fibers has grown more rapidly than that of any other man-made fiber. Many factors have contributed to this growth. Polyester's unique physical properties of strength, high modulus, elasticity, and durability are the basis for its success. The tailorability of the fiber makes it possible to generate a whole family of property variants for a wide variety of end uses. The ready availability and low cost of the raw materials, the continuing advances in polymerization technology, and the versatility of the melt spinning process have also been major factors in establishing polyester as the leading man-made fiber. New end uses have had a major impact on the growth of polyester. Most notable was the introduction of durable press fabrics for clothing and home furnishings. The consumer preference for easy-care fabrics and garments makes the durable press area one of continuing growth. Two relatively new areas where growth is expected to continue at a rapid rate are tire cord and textured knits for women's and men's outerwear. 相似文献
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Methyl bromide, used at a concentration‐time product of 800 mg h/l at 25 °C with a relative humidity of 70%, was successful in eliminating salmonellae from artificially contaminated poultry foodstuffs. Chicks fed on this fumigated food remained free from the infection and there were no adverse effects on growth rate. 相似文献
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M P Brown R H Kelly R R Gronwall S M Stover 《American journal of veterinary research》1984,45(3):578-580
Six healthy adult mares were given a single IV dose (25 mg/kg of body weight) of chloramphenicol sodium succinate. Chloramphenicol concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The highest measured serum chloramphenicol concentration was 6.21 micrograms/ml at 0.5 hour. Chloramphenicol was detected in synovial and peritoneal fluids, with mean peak concentrations of 3.89 micrograms/ml and 3.50 micrograms/ml, respectively, at 0.5 hour. Serum and synovial concentrations declined rapidly and were not measurable at 3 hours. Chloramphenicol could not be detected in peritoneal fluid at 6 hours. The serum half-life was 0.43 hour and the apparent volume of distribution was 2.83 L/kg. Urine concentrations of chloramphenicol peaked at 0.5 hour at 106.72 micrograms/ml and also declined rapidly. The drug could not be detected in the urine at 36 hours. 相似文献