Results 211 to 220 of about 36,860 (259)

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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Albinism in the Common Frog

Nature, 1933
ALBINISM in the common grass frog is a very rare phenomenon and as no mention is made of it in most works on albinism, its occurrence in four parts of England seems worth recording. The specimens I have seen recently came from Somersetshire, Wiltshire, Oxfordshire and Lancashire.
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Handbook of Common New Guinea Frogs

Copeia, 1977
Handbook of common New Guinea frogs , Handbook of common New Guinea frogs , مرکز فناوری اطلاعات و اطلاع رسانی ...
M. J. Littlejohn, J. I. Menzies
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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 EFFECT OF TESTOSTERONE ON THE SPERMATOGENESIS OF THE COMMON FROG, RANA TEMPORARIA

Acta Endocrinologica, 1960
ABSTRACT Testosterone pellets have been implanted into the dorsal lymph sac of common frogs (Rana temporaria) at three different stages of the spermatogenetic cycle. Testosterone appears to cause complete inhibition of the multiplication divisions of the spermatogonia.
P, van OORDT, S L, BASU
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Spawning Date of the Common Frog

Nature, 1934
IN a former communication1 I announced certain conclusions on the effect of the weather upon the spawning date of the common frog, Rana temporaries. Since then, a number of new facts have come to light.
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Role of hydration in ovulation of common frog oocytes in vitro

Russian Journal of Developmental Biology, 2013
Stimulation of ovulation of the common frog Rana temporaria oocytes with homologous pituitary extract caused an increase in their volume. Factors that are known to inhibit hydration in teleostean oocytes (potassium-free Ringer solution and inhibitor of Na+, K(+)-ATPase--ouabain), as well as use of aquaporin inhibitors (mercuric chloride and ...
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[Chronology of the embryonic development of the common frog].

Ontogenez, 1984
The tables of embryonic development of the common frog (Dabagyan, Sleptsova, 1975) have been made more precise: more precise timing of successive developmental stages (in the number of tau 0) from fertilization till hatching was provided and new drawings of the embryos during gastrulation were given.
L V, Riabova, O B, Trubnikova, L A, Sleptsova   +2 more
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[Physiological polymorphism in a population of the common frog. I. The polymorphism of a population of the common frog for the trait of muscle tissue heat resistance].

Tsitologiia, 1979
A study was made of heat resistance (36+/-0.2 degrees C) of m. interphalangealis of the third finger of a hind extremity in animals of one population of Rana temporaria L. living on the boundary between Leningrad region and Pskov region. Within this population, the existence of three groups of individuals differing in heat resistance levels of their m.
T A, Dzhamusova, N V, Kesamanly
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Heterosis in the common European water frog

Naturwissenschaften, 1979
H G, Tunner, H, Nopp
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