Metabolic requirements for the uptake and retention of H3Norepinephrine (H3NE) by isolated frog ventricle

Resumen El tratamiento con iodoacetato (IAA), no modifica la incorporación y retencion de H³Norepinefrina (H³NE) al ventriculo aislado deRana oxigenado y suspendido en ringer con o sin glucosa. Bajo atmosfera de Nitrógeno y ausencia de glucosa, la incorporacion de H³NE es bloqueada en un 58%; en estas condiciones el IAA produce un ulterior bloqueo del 33%.     

Propagation of mouse hepatitis virus (MHV-3) in monolayer cell cultures from liver of new-born mice

Riassunto È stata provata la possibilità di coltivare MHV-3 in colture monostrato di cellule di fegato di topo neonato ottenute per tripsinizzazione. Per questo tipo di coltura è indispensabile l'aggiunta alla tripsina di metilcellulosa e di estratto embrionale di pollo al terreno di coltura. MHV-3 si moltiplica attivamente in queste colture, raggiungendo elevate concentrazioni nel liquido di coltura e producendo effetto citopatico.     

The control of the frog (Rana esculenta) thumb pad

Summary Extirpation of the pars distalis of the pituitary or castration in any period of the year cause thumb pad regression. Thumb pad development is regulated by an interaction of both temperature and androgenic hormones.Work done under the C.N.R.-finalized project Biologia della Riproduzione.     

Infection of frog tadpoles (Amphibia) by insect parasitic nematodes (Rhabditida)

Summary Infective stage juveniles ofNeoaplectana carpocapsae (Steinernematidae) andHeterohabditis heliothidis (Heterorhabditidae) were able to penetrate through the alimentary tract of young tadpoles ofHyla regilla (Hylidae) andXenopus laevis (Pipidae) and enter the body cavity. Some infectives ofN. carpocapsae were able to release their symbiotic bacterium,Xenorhabdus nematophilus inside the host and in two cases, the nematodes developed into adult females before they perished. Tadpole mortality was associated with foreign bacteria entering the penetration holes made by the invading nematodes. The infective stage juveniles of both nematodes frequently encountered a host defense reaction upon reaching the tadpole's infective stage juveniles of both nematodes frequently encountered a host defense reaction upon reaching the tadpole's coelom.     

Rhythmic activity in frog (Rana pipiens) visual system

Zusammenfassung Nachweis, dass die Netzhaut-Ganglienzellen dritter Klasse beiRana pipiens auf Beleuchtungsperiodenausgleich reaktiv rhythmische potentialfolgen von bursts und firing erzeugen. Als wirksamste Beleuchtungsperioden erwiesen sich solche im mesopischen Bereich bei Mindestdauer von 15 sec. Weder skotopische noch photopische Belichtungen führten zu rhythmischer Aktivität.     

Effect of the insecticide Sumithion (Fenitrothion) on embryonic development in a frog

Cellular and Molecular Life Sciences - The toxic effects of Sumithion on developing embryos of a frog,Microhyla ornata, were investigated for a period of 96h. Abnormalities observed were loss of...     

The response of frog taste cells (Rana nigromaculata andRana catesbeana)

Zusammenfassung Die Registrierung der Rezeptorpotentiale einzelner Geschmackszellen von Raniden (R. nigromaculata undR. catesbeana) bei Reizung mit 4 Grundgeschmacksarten mittels Glasmikroelektrode ergibt: Ruhepotential der Rezeptorzellen 10–35 mV (innen negativ). Die einzelnen Geschmackszellen antworten auf mehr als 2 Geschmacksarten und zeigen im Hinblick auf ihre Antwortmuster zellcharakteristisches Verhalten.     

Cytotaxonomy of the Seychelles tree frog,Megalixalus seychellensis (Duméril and Bibron) (Amphibia: Hyperoliidae)

Summary The Seychelles tree frog,Megalixalus seychellensis has 2n=24 chromosomes of gradually decreasing length. Pairs 2, 3, and 4 are submetacentric, and the remaining pairs are metacentric. The karyotype affirms hyperoliid assignment of this species, and indicates a link between the Seychellean fauna and the African-Madagascan faunas.Research supported by the National Geographic Society.