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Résumé Chez les cailles japonaises, le complexe glandulaire du cloaque est en fait localisé dans la lèvre dorsale du cloaque et non de l'anus. Il existe un complexe glandulaire similaire et très petit du côté ventral. La glande active se colore intensément avec le réactif périodique «acide Schiff», avec la fuchsine aldéhyde, avec le bleu d'alciane et métachromatiquement avec le bleu de toluidine. Ceci indique la présence d'une sécrétion de glycomucoprotéines. Le liquide transparent sécrété est transformé en masse blanche mousseuse au contact des bactériesE. coli etProteus mirabilis, présentes en quantités équivalentes dans le proctodeum. Les gaz émis consistent probablement en H2 et CO2, ce dernier peut agir comme tampon et stabiliser le pH de la sécrétion autour de la valeur 6,5.

This work was supported by U.S.P.H.S. grant No. ES 00054, Support for Toxicology Center, and by NASA research grant No. NGR 05-004-028.  相似文献   

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Summary The midbrain areas that yielded calling with the smallest currents were within the nucleus intercollicularis and isthmi complex. Natural calls were evoked, but they could not be localized. Rather, some calls were more easily evoked than others.Acknowledgments. We are very grateful to The Royal Society and the Central Research Fund, University of London for financial support.  相似文献   

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Ecdysteroids are hormones controlling cell proliferation, growth and the developmental cycles of insects and other invertebrates1. They are occasionally present in various unrelated plants for no apparent reason; no phytohormonal function has yet been identified. In certain cases, ecdysteroids are accumulated to high levels in leaves, roots or seeds. Some ecdysteroid-containing plants have been known as medicinal plants for centuries. One of them,Leuzea carthamoides Iljin (Asteraceae), growing in Central Asia, contains 0.4% ecdysteroid in dry roots and 2% in seeds. A pharmacological preparation from this plant, Ecdisten, is already available as a commercial preparation for its anabolic, tonic and other effects, for medical use (review2). It remained problematic, however, whether ecdysteroids were truly responsible for these effects, becauseLeuzea contains a number of other biologically active compounds in addition to ecdysteroids. We extracted and purified ecdysteroids from the seeds ofLeuzea. With 6 g of 96% 20-hydroxyecdysone (20E), we made a large-scale feeding assay with Japanese quail to find out whether ecdysteroid alone could duplicate the anabolic effects of the seeds. We found that the 96% ecdysteroid increased the mass of the developing quails in a dose-dependent manner, with the rate of increase proportional to the ecdysteroid content in the seeds; there was a 115% increase in living mass with 100 mg kg–1 of pure 20E compared with 109.5% increase with 100–180 mg kg–1 20E equivalents in the seeds. We conclude that the plethora of growth-promoting, vitamin-like effects induced in vertebrates byLeuzea is mediated by ecdysteroids.  相似文献   

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Summary Electrolytic bilateral lesions of the nuclei habenulae were made in male, adult photostimulated quail. Habenular destruction led to a marked decrease in the plasma thyroxine level (40%), whereas sham operated birds did not differ from controls. This result appears to be somewhat different from those obtained in mammals and the mechanisms of habenular-thyroid interrelationships are unknown.  相似文献   

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Electrolytic bilateral lesions of th nuclei habenulae were made in male, adult photostimulated quail. Habenular destruction led to a marked decrease in the plasma thyroxine level (40%), whereas sham operated birds did not differ from controls. This result appears to be somewhat different from those obtained in mammals and the mechanisms of habenular-thyroid interrelationships are unknown.  相似文献   

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Summary Acute bilateral superior cervical ganglionectomy (SCGX) completely prevents the nocturnal rises in pineal N-acetyltransferase (NAT) activity and melatonin content in male rats kept in light-dark cycles of 1410. Unilateral SCGX causes the NAT and melatonin levels to be intermediate between those in sham-operated control rats and those in rats from which both ganglia had been removed.Supported by NSF, grant No. PCM 77-05734.  相似文献   

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Acute bilateral superior cervical ganglionectomy (SCGX) completely prevents the nocturnal rises in pineal N-acetyltransferase (NAT) activity and melatonin content in male rats kept in light-dark cycles of 14:10. Unilateral SCGX causes the NAT and melatonin levels to be intermediate between those in sham-operated control rats and those in rats from which both ganglia had been removed.  相似文献   

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Résumé Après une injection intrapéritonéale de thymidine3H à la caille japonaise pondeuse, nous avons trouvé une incorporation de ce précurseur dans des organites cytoplasmiques subcorticaux des oocytes, quelques jours avant leur ovulation.  相似文献   

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Summary No evidence was found for ribosomal DNA amplification in the oocytes of the Japanese quail, before or during folliculogenesis. DNA synthesis in the somatic cells, involved in follicle formation, starts at the medullar side of the basement membrane. The localized sterilization of the quail ovary after administration of3H-thymidine (3H-TdR) seems to be due to radiation-induced lesions in the follicle forming somatic cells, rather than to direct radiation damage of the oocyte.The author is very grateful to Prof. Dr L. Vakaet, R.U.C.A.—Antwerpen, for his valuable suggestions and to Mrs D. De Wolf-Van Rompaey for her excellent technical assistance.  相似文献   

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Summary Incorporation of3H-uridine was studied during pachytene and diplotene stages of quail oocytes. No labelling could be detected during early pachytene. During advanced and late pachytene, labelling simultaneously appeared on the macrochromosomes and on certain michromosomes in the zone where they emerge from the chromocentric surface periphery. The latter localization corresponds to the region of ribosomal RNA synthesis. At diplotene the same localizations were labelled with a considerably increased intensity.  相似文献   

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