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Concurrent cutaneous abscesses and swinepox were observed in a herd of swine. An ungroupable hemolytic streptococcus was isolated from the abscesses. Tests indicated that streptococci isolated from different swine were similar if not identical. Swinepox lesions were observed on swine only after weaning. Lice (Haematopinus suis) were numerous on the suckling and weaned swine and appeared to be resistant to lindane. Abscesses, swinepox, and lice were eliminated after the swine were treated with an organic phosphate insecticide and antibacterial agents were added to the rations.  相似文献   
995.
The relationships among exogenous adrenocorticotropin (ACTH), plasma corticosteroids, and circulating leukocytes were studied in 7 lactating cows. Blood samples were obtained from jugular cannulas at -2, -1, and 0 hours before ACTH was injected (base line) and 0.25, 0.50, 1, 2, 3, 6, and 24 hours after injection. Plasma corticosteroids were increased progressively by injecting doses of ACTH between 1 and 200 IU. Plasma corticosteroids reached peak concentrations between 15 and 30 minutes and returned to base line within 1 to 3 hours after 1, 5, and 10 IU doses of ACTH were injected, but required as long as 6 hours after injection of 100 and 200 IU. Base line counts of circulating leukocytes averaged 7.3 X 10(3) cells/mm3 and remained unchanged after injecting 0 and 1 IU of ACTH (P less than 0.05). Significant dose-dependent increases in circulating leukocytes were detected within 2 hours after administering 5, 10, and 100 IU of ACTH. Responses to 100 and 200 IU were similar. The average concentration of leukocytes increased up to 6 hours after ACTH administration and returned to base line values within 12 to 24 hours in cows injected with 5 and 10 IU, but not until 48 hours in cows injected with 100 and 200 IU of ACTH. In contrast to the delayed and sustained responses observed for leukocytes, corticosteroid responses were rapid and transient. Moreover, the administration of 200 IU of ACTH was considered to increase circulating corticosteroids and leukocytes beyond that found in dairy cattle exposed to stress associated with overmilking, acute coliform mastitis, or parturition.  相似文献   
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Amnesia was obtained following electroconvulsive shock in rats trained at one-trial passive avoidance of immersion in ice water. Avoidance behavior was restored when noncontingent foot shock was administered outside the training apparatus. The qualitative differences between ice water and foot shock demonstrate that the agent inducing recovery of memory need not be physically similar to the reinforcer used during training. These findings are interpreted as supporting a retrieval failure view of experimental amnesia.  相似文献   
998.
Miller DM 《Science (New York, N.Y.)》1963,139(3559):1060-1061
"Flickering," which has been observed in the erythrocytes of many animals, has now been observed in the protoplasts of Bacillus megaterium.  相似文献   
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