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991.
The safety and immunogenicity of inactivated porcine parvovirus (PPV) vaccines were investigated. Both beta-propiolactone and formalin successfully inactivated virus without destroying immunogenicity, which was considerably enhanced by incorporation of a gel adjuvant in the vaccine. Using the formalised-gel vaccine, initial antibody responses were demonstrated in susceptible piglets and adult pigs at 7 days after vaccination. These antibody responses persist at significant levels for at least 6 months after vaccination. Antibody levels increased up to 16 fold when revaccination was carried out. Vaccination of gilts with low level (passive) immunity resulted in antibody responses comparable to those recorded in susceptible pigs. The vaccine was safe as determined by absence of residual virus in the vaccine, absence of viraemia and excretion in vaccinted stock, and absence of effect on litters of sows vaccinated at different gestational ages. Vaccine stored at 4 degrees C for 6 months was as immunogenic as fresh vaccine. 相似文献
992.
Emphysematous cholecystitis not associated with diabetes mellitus was diagnosed in three dogs. All three dogs were examined because of vomiting. Neutrophilia, elevated serum alkaline phosphatase, and normal serum glucose were present in each animal. A gas-filled gallbladder and pericholecystic gas were seen radiographically in all three dogs; a cholecystolith was present in one dog. A cholecystectomy was performed on two dogs. Cultures of bacteria from these two bladders revealed Clostridium sp. One of these dogs was euthanized because of acute renal tubular necrosis that was diagnosed after ten days of treatment with gentamicin. The second dog recovered without incident. The third dog was treated successfully with antibiotics. 相似文献
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D G Brown D F Johnson 《Journal of the American Veterinary Medical Association》1970,157(11):1914-1918
996.
Growth of Rift Valley fever virus in human diploid (WI-38) cells 总被引:1,自引:0,他引:1
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Johnson RG 《Science (New York, N.Y.)》1959,129(3357):1221-1223
When hot saturated solutions of thermal copolymers containing the 18 common amino acids are allowed to cool, huge numbers of uniform, microscopic, relatively firm, and elastic spherules separate. The place of this phenomenon in a comprehensive theory of original thermal generation of primordial living units is considered. 相似文献