Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Amphibia”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
PubMed1976

[Studies On The Parasites Of Korean Amphibia: 1. Trematodes Of Amphibians]

An investigation on the trematodes of Korean amphibians was carried out during the period from April to September of 1976. A total of 883 amphibians of 6 species were examined. These frogs, toads and salamanders were collected in the areas of the Han river side. And also these amphibians comprised 775 Rana nigromaculata, 53 Rana rugosa, 21 Hyla arborea japonica, 2 Bufo bufo gargarizans, 2 Gallula tornieri and 30 Hynobius leechi. Out of the results of this work, 7 species of trematodes belonging to 2 orders were found as follows: 1. Monogenea: Diplorchis ranae Ozaki, 1931. 2. Digenea: Diplodiscus japonicus (Yamaguti, 1936), Gorgodera japonica Yamaguti, 1936, Haematoloechus sibiricus japonicus(Yamaguti, 1936), Mesocoelium brevicaecum Ochi, 1929, Loxogenes liberum Seno,1980, Pleurogenoides japonicus (Yamaguti, 1936).

Journal Article↗
PubMed2002

Karyological and flow cytometric evidence of triploid specimens in Bufo viridis (Amphibia Anura).

Karyological and flow cytometric (FCM) analyses were performed on a group of 14 green toads of the Bufo viridis species from seven Eurasian populations. Both approaches gave concordant results concerning the DNA ploidy level. All the populations examined were represented exclusively by diploid or tetraploid specimens, except one, where triploids were found. Results evidenced an interpopulation variability in DNA content against the same ploidy level, as well as an unusually high number of triploids in a particular reproductive place. The origin of polyploidy and the presence and persistence of a high number of triploids in a particular population are discussed.

Animals↗
PubMed1990

Occurrence of tetrathyridia of Mesocestoides sp. (Cestoidea: Cyclophyllidea) in North American anurans (Amphibia).

A new host and geographic locality record is reported for tetrathyridia of Mesocestoides sp. in two species of ranid frogs (Rana berlandieri and R. pipiens) from Texas and New York, respectively. Tetrathyridia were found encapsulated in liver and mesenteries of the hosts. Morphological examination and experimental inoculation of these tetrathyridia into mice demonstrated the absence of capacity for asexual proliferation. Overall prevalence of infection was low in anurans from Arkansas, Texas and New York, but intensities can be generally high. In addition, a summary of frogs and toads from North America reported as hosts of tetrathyridia of Mesocestoides sp. is presented.

Animals↗
PubMed1992

Testicular myxosporidiasis in the flat-backed toad, Bufo maculatus (Amphibia: Bufonidae), from Cameroon, Africa.

Macroscopic cysts measuring less than or equal to 860 x 500 microns were found in the testes of a flat-backed toad, Bufo maculatus, collected in Cameroon, West Africa. On histologic examination, the cysts contained numerous spores of a Myxobolus sp. (Myxozoa: Myxobolidae). Spores in fixed tissues measured 9.2 microns long, 8.9 microns wide, and 4.0 microns thick; the range of values for length, width, and thickness were 8.8 to 9.6 microns, 8.6 to 9.4 microns, 3.6 to 4.4 microns, respectively (n = 20). The shape index (length/width) was 1.03, and ranged from 1.00 to 1.09. Pathology was limited to a slight constriction of adjacent seminiferous tubules by the cysts. No host inflammatory response was noted. This myxozoan is distinct from all other members of the genus infecting anurans and is assigned the name Myxobolus bufonis sp. n.

Animals↗
PubMed1976

Histochemical studies on the effect of thyroid hormone on alkaline and acid phosphatase activities in liver of fish and amphibia.

The Lata fishes (Ophicephalus punctatus) showed increased alkaline and acid phosphatase activities in liver after immersion for 15-30 days in thyroxine-containing medium (0.025 mug/ml). A single injection of thyroxine (1-2 mug/g of body weight) caused increased acid phosphatase activity in liver of Lata fish in comparison to the controls on the 5th day after experiment but the alkaline phosphatase activity remained unchanged. Both alkaline and acid phosphatases showed increased activities in liver of Lata fishes treated with a single injection of 4 mug of thyroxine per g of body weight on the 5th day. Immersion of Lata fishes in thiourea solution (1 mg/ml) for 15 days did not show any alteration in alkaline or acid phosphatase activities but these enzyme activities decreased after 30 days' immersion in thiourea solution in comparison to the controls. A seasonal variation of alkaline and acid phosphatase activities was observed in liver of Lata fishes. More alkaline phosphatase activity was found in liver of summer fishes than in winter fishes. The winter fishes showed more acid phosphatase activity than the summer fishes. Three consecutive injections of thyroxine (0.1 mug/g of body weight) to toads (Bufo melanostictus) caused increased alkaline and acid phosphatase activities in liver on the 5th day of the experiment, in comparison to the controls.

Acid Phosphatase↗
PubMed1978

[Ultrastructural localization of 3-beta-hydroxysteroid dehydrogenase activity in the glandular tissue cells of the testis of Pleurodeles waltlii Michach. (Amphibia, Urodela)].

With the potassium ferricyanide method, the localization of the sites of 3 beta-hydroxysteroid dehydrogenase activity has been investigated in the glandular tissue cells, previously fixed, of the Pleurodeles testis. An abundant copper ferrocyanide precipitate, the final reaction product, is observed in the vicinity of the external faces of the membranes of the smooth endoplasmic reticulum, or in contact with them. A very weak reaction occurs in mitochondrial cristae.

3-Hydroxysteroid Dehydrogenases↗
PubMed1999

Karyotype study of Rana camerani and comparisons with the other 26-chromosome European brown frog species (Amphibia, Anura).

The results of a detailed morphological and morphometrical chromosome analysis of Rana camerani (2n = 26) are described. It was established that the karyotype of this species consisted of three homologous pairs of large metacentrics, two homologous pairs of large submetacentrics, three homologous pairs of small metacentrics, two homologous pairs of small submetacentrics, and three homologous pairs of small subtelocentrics. Morphologically discernible sex chromosomes were not found. The similarity and peculiarities in the R. camerani karyotype and those of R. temporaria, R. dalmatina and R. graeca are discussed. This comparative karyotype analysis has suggested the possibility for developing a general chromosomal formula, by means of which these 26-chromosome species could be characterized.

Animals↗
PubMed2000

Functional morphology of the inner ear and underwater audiograms of Proteus anguinus (Amphibia, Urodela).

Octavolateral sensory organs (auditory and lateral line organs) of cave salamander Proteus anguinus are highly differentiated. In the saccular macula of the inner ear the complex pattern of hair cell orientation and the large otoconial mass enable particle displacement direction detection. Additionally, the same organ, through air cavities within the body, enables detection of underwater sound pressure changes thus acting as a hearing organ. The cavities in the lungs and mouth of Proteus are a resonators that transmit underwater sound pressure to the inner ear. Behaviourally determined audiograms indicate hearing sensitivity of 60 dB (rel. 1 microPa) at frequencies between 1 and 10 kHz. The hearing frequency range was between 10 Hz and 10 kHz. The hearing sensitivities of depigmented Proteus and black Proteus were compared. The highest sensitivities of the depigmented animals (N=4) were at frequencies 1.3-1.7 kHz and it was 2 kHz in black animals (N=1). Excellent underwater hearing abilities of Proteus are sensory adaptations to cave habitat.

Acoustic Stimulation↗
PubMed2000

The ultrastructure of photoreceptor cells in the pineal organ of the blind cave salamander, Proteus anguinus (Amphibia, Urodela).

We studied ultrastructure of the photoreceptor cells in the pineal organ of blind, depigmented, neotenic cave salamander, Proteus anguinus. Unlike in epigean vertebrates the outer segments of most photoreceptor cells consists of concentrically arranged lamellae, however; in few cells, the outer segments contain 7-9 plasma membrane disks. In both types of photoreceptor cells the outer segments enclose lumps of vesicles of different sizes. The photoreceptor cells of Proteus anguinus are similar to those in other cavernicolous fish species.

Animals↗
PubMedDate not supplied

Cranial kinesis in the amphibia: a review.

All extant orders of amphibians are characterized by kinetic skulls. Main type of intracranial movability in amphibians is pleurokinetism, that is supplemented in different amphibian groups by various types of rhyncho- and prokinetism. The most primitive pattern of cranial kinesis is revealed in the stegocrotaphic gymnophions. More paedomorphic species retain general cranial flexibility that is characteristic of larval skull. That is unfavourable for evolution of well-regulated (adult) cranial kinesis and related feeding adaptations. Kinetism is also reduced in the species with heavily ossified skulls. Adaptive role and evolution of cranial kinesis in amphibians are discussed.

Amphibians↗
PubMed1975

[A radioautographic study of changes in the intensity of total protein synthesis in the limb tissues of anuran amphibia during loss of regenerating capacity].

The intensity of total protein synthesis was estimated by 3H-lysine incorporation in the hind limb tissues of mesodermal origin in the common frog tadpoles. In the course of limb development and loss of regenerative ability, the intensity of 3H-lysine incorporation in the differentiating muscle tissue and cartilage epiphysis increased; the cartilage diaphysis is characterized by the low level of 3H-lysine incorporation. At the stage Ia of regeneration after the limb amputation the intensity of labeling in the tissues of organ residue descreases until the stage of regeneration blastema formation and then, during the formation of limb rudiment, rapidly increases. The blastema cells are characterized by the high intensity of 3H-lysine incorporation. At the stage IIIa of wound healing after the limb amputation, the intensity of 3H-lysine incorporation in the differentiated muscles and cartilage epiphysis gradually decreases. The intensity of labeling in the scar cells is high enough.

Animals↗