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421.
Plasma ACTH and cortisol levels in the bovine fetuses over the period of 5 to 9 months of gestation and in the neonates immediately after birth and at 5 days old were studied. In the bovine fetuses, the plasma ACTH levels ranged from 60.8 +/- 17.8 to 71.3 +/- 19.7 pg/ml over the period of 5 to 7 months of gestation. It increased rapidly to 239.2 +/- 261.5 pg/ml at 8 months and to 406.9 +/- 409.4 pg/ml at 9 months of gestation. In the neonates immediately after birth it decreased to 182.3 +/- 110.7 pg/ml. The plasma cortisol levels ranged from 3.23 +/- 2.12 to 3.85 +/- 2.52 ng/ml over the period of 5 to 8 months of gestation and increased to 8.10 +/- 4.88 ng/ml at 9 months of gestation. It then increased rapidly to 88.35 +/- 42.78 ng/ml in the neonates immediately after birth. The correlation between plasma ACTH and cortisol levels in the fetuses of 5 to 7 months of gestation was not significant, but in the fetuses of 8 and 9 months of gestation and neonates were significant. However, especially immediately after birth, the increase in plasma cortisol occurred without a concomitant rise in plasma ACTH. According to these findings, it is suggested that the pituitary-adrenocortical axis in bovine fetus matures in the later stage of gestation and an increase of sensitivity in the fetal adrenal gland to ACTH may serve as a trigger for the onset of parturition.  相似文献   
422.
Japan has scarcely any potassic resource in her country. Therefore, the shortage was severe in the second world war. In this time I had investigated the fertilizer utilization of many potassic minerals, such as liparite, alunite, glauconite and vermiculite in this country. The potassium jarosite was discovered for the first time at Gumma limonite mine by Katayama and Saito in 1947n. Since then, the many deposites were found out at such places as Suwa Mine in Nagano prefecture, Mitsui-Aso Mine in Kumamoto prefecture and several mines in the Hokkaido district.  相似文献   
423.
Gizzard lesions were formed in specific-pathogen-free (SPF) white leghorn chickens inoculated with fowl adenovirus (FAV). The virus, serotype 1 FAV 99ZH strain (FAV-99ZH), was originally isolated from the gizzard mucosa of commercial broiler chickens exhibiting gizzard erosion with intranuclear inclusion bodies. Five-day-old and 53-day-old SPF white leghorn chickens were inoculated with FAV-99ZH by both oral and ocular routes and then examined at necropsy on days 3, 5, 7, 10, 14, and 21 postinoculation (PI). There were no clinical signs in any of the chickens after the inoculation. Focal gizzard lesions occurred macroscopically, however, in inoculated chickens at several experimental periods. FAV was recovered from tissue samples of the proventriculus, gizzard, pancreas, and rectum by day 10 or 7 PI but was not recovered from liver samples of any of the chickens. These results indicate that FAV isolated from gizzard erosion is able to reproduce gizzard lesions as necrosis and erosion in SPF white leghorn chickens and that it may have a greater degree of tissue tropism in gizzards and other digestive organs than in the liver.  相似文献   
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