Results 121 to 130 of about 2,812 (174)

Isolation of Neurohypophysial Hormones of Rana temporaria

Nature New Biology, 1972
THE neurohypophysial hormones of several vertebrates have been identified1–3, but the nature of the neurohypophysial principles of amphibians is in doubt. Vasotocin (8 Arg-oxytocin) is known to be present, but the oxytocic component could be either oxytocin, mesotocin (8 Ileu-oxytocin) or both1–7. Since the neutral peptides are difficult to distinguish
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Adenohypophysis and growth in tadpoles of Rana temporaria

General and Comparative Endocrinology, 1978
Growth of the Rana temporaria tadpole was investigated after (1) adenohypophysectomy, (2) autografting the adenohypophysis to the tail, and (3) homografting an extra adenohypophysis into the tail of the otherwise normal tadpole. All operations were performed using the early tail-bud embryo.
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MHC zygosity in the frog, Rana temporaria

Immunogenetics, 1984
The major histocompatibility complex (MHC) zygosity of the field-collected frogs, Rana temporaria, was detected by progeny testing. Groups of sibling tadpoles were grafted with intrafamilial tail-tip allografts and the ratio of rapidly rejected allografts to slowly rejected ones was estimated.
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Photoprotection in tadpoles of the common frog, Rana temporaria

Journal of Photochemistry and Photobiology B: Biology, 2000
The common frog, Rana temporaria, spawning at altitudes up to 2600 m, is potentially threatened by UVB radiation. In laboratory experiments we found a specifically UVB absorbing substance (UVAS) in the skin of tadpoles with maximum absorption between 290 and 300 nm. The production of UVAS is induced by both visible light and ultraviolet radiation.
R, Hofer, C, Mokri
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Behavioural adaptations of Rana temporaria to cold climates

Journal of Thermal Biology, 2015
Environmental conditions at the edge of a species' ecological optimum can exert great ecological or evolutionary pressure at local populations. For ectotherms like amphibians temperature is one of the most important abiotic factors of their environment as it influences directly their metabolism and sets limits to their distribution.
Gerda, Ludwig, Ulrich, Sinsch, Bernd, Pelster   +2 more
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Karyometric studies of the preoptic nucleus of Rana temporaria

General and Comparative Endocrinology, 1961
Abstract Karyometric studies in the area of the preoptic nucleus in Rana temporaria show the existence of an annual cyclical variation of the volumes of the nuclei of the neurosecretory cells. The nuclei are largest during spring and summer. They are smallest during hibernation.
K, DIERICKX, N, VAN MEIRVENNE
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The Common Frog Rana temporaria

1991
The oocytes, embryos, and larvae of Rana temporaria have long been traditional subjects of diverse experimental embryological studies. Experimental embryologists have often used the embryos of R. temporaria for studies concerning the mechanisms of development. In the first half of this century experiments were carried out on eggs collected from natural
N. V. Dabagyan, L. A. Sleptsova
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The magnocellular preoptic nuclei and the reproduction in Rana temporaria

Zeitschrift f�r Zellforschung und Mikroskopische Anatomie, 1965
In Rana temporaria, changes of activity of the magnocellular neurosecretory preoptic nuclei in close correlation with ovulation, spermiation and copulation were observed. In accordance with previous experiments, the present observations suggest that the neurosecretory nuclei could play a part in the mechanism of ovulation, spermiation and copulation.
K, Dierickx, F, Vandesande
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Cyclical mitotic activity in the adeno-hypophysis of Rana temporaria

Zeitschrift f�r Zellforschung und Mikroskopische Anatomie, 1971
In the pars distalis, the pars intermedia and the pars tuberalis of the hypophysis of Rana temporaria, an annual mitotic cycle is described.
Dierickx, Kamiel, Goossens, Noel, Van Den Branden, Christiane   +2 more
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Immunofluorescent localization of calcitonin in the ultimobranchial gland of Rana temporaria and Rana pipiens

Histochemie, 1971
Calcitonin-like immunoreactivity has been demonstrated by immunofluorescence in the cells of the ultimobranchial gland of two species of Rana, using an indirect (sandwich) technique with anti-pure porcine calcitonin serum. The possibility of cross-reactivity, between the amphibian hormone and anti-porcine calcitonin antibody, had been anticipated on ...
S, Van Noorden, A G, Pearse
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