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 1,765 records · Page 98Linked to original sources
PubMed1960

Preparation of monolayer cell cultures from tissues of some lower vertebrates.

Cold trypsin dispersion at pH 7.2 was used to obtain cultivable cells and cell groups from tissues of six species of fresh-water bony fishes, a frog, and a turtle. The cells readily attached to glass and were capable of at least limfted, and in some cases extended, division in media consisting of commercially available components.

Amphibians↗
PubMed1964

PTERIDINES AS PIGMENTS IN AMPHIBIANS.

Extracts of brightly colored skins from nine amphibian species were analyzed chromatographically. In yellow skin in which xanthophores predominated, relatively large quantities of sepiapterin were found, while in red skin which was laden with erythrophores, three drosopterins were most prevalent. Frozen sections of skin indicated that pteridines were present within chromatophores, either alone or accompanied by carotenoids. It is concluded that sepiapterin and three drosopterins are utilized as pigments in amphibians and it is suggested that other less brightly colored pteridines also function in this respect. It no longer seems proper to make the tacit assumption that bright pigmentation of amphibians is due only to the presence of carotenoids.

Amphibians↗
PubMed1962

Acetylmethylcarbinol production and the classification of aeromonads associated with ulcerative diseases of ectothermic vertebrates.

Page, L. A. (Biological Research Institute, San Diego, and University of California, Davis). Acetylmethylcarbinol production and the classification of aeromonads associated with ulcerative diseases of ectothermic vertebrates. J. Bacteriol. 84:772-777. 1962.-Quantitative colorimetric tests were made for acetylmethylcarbinol (AMC) production by 14 Aeromonas isolates from ulcerous lesions of snakes, lizards, frogs, and other animals, and by 27 cultures of "identified" aeromonads. The tests revealed that: (i) some strains failed to produce AMC, while the other strains produced AMC in amounts of 5 to > 100 mug/ml of culture; (ii) the reagents employed in the standard method of Barritt failed to detect AMC in concentrations below 35 mug/ml; and (iii) certain strains reported as producing AMC at 23 C and not at 37 C (or vice versa) produced AMC at both temperatures, but at one temperature produced AMC at a level below the sensitivity of the qualitative test. The strains representing the two biotypes could not be distinguished on the basis of their morphology, habitat, pathogenicity for mice or snakes, or serological specificity. Therefore, the Aeromonas classification proposed by Ewing, Hugh, and Johnson, who incorporated the two biotypes into one species, was followed, and the new isolates were designated A. hydrophila.

Acetoin↗
PubMed1963

EFFECT OF ENVIRONMENTAL TEMPERATURES ON INFECTION WITH MYCOBACTERIUM MARINUM (BALNEI) OF MICE AND A NUMBER OF POIKILOTHERMIC SPECIES.

Clark, H Fred (Communicable Disease Center, Atlanta, Ga.), and Charles C. Shepard. Effect of environmental temperatures on infection with Mycobacterium marinum (Balnei) of mice and a number of poikilothermic species. J. Bacteriol. 86:1057-1069. 1963.-An exploration was made of the effect of environmental temperature on infections with Mycobacterium marinum of mice, young opossums, and bats, and of 50 species of poikilothermic animals. In artificial medium (7H9 broth) M. marinum grew most rapidly from 25 to 35 C, with generation times of 4 to 6 hr. At 37 C, the generation time was 14 hr; at 20 C, 20 hr; and, at 15 C and lower, little growth was observed. In mice, deep body temperatures were found to be 36.5 to 37.3 C at environmental temperatures of 4 to 30 C. At an environmental temperature of 34 C, they averaged 39.1 C; at 37 C they averaged 40.2 C. Foot-pad temperatures were within a few degrees of ambient temperatures from 10 to 34 C. In mouse foot-pad infections, the optimal environmental temperature for infection was 20 C, and the generation time of the infecting bacilli at this environmental temperature was about 15 hr. Intravenously inoculated mice developed peripheral infections of nose, feet, and tail at environmental temperatures of 4 to 30 C. At these temperatures, they had severe pneumonic involvement, and the mice at lower temperatures tended to succumb most rapidly to systemic infection. At 34 C, the intravenously infected mice did not develop peripheral infections and there was no pulmonary involvement. Young opossums, whose deep body temperatures are only 34 to 36 C, were inoculated in the foot-pad and intravenously. Foot-pad infection developed without systemic involvement. Bats, which assume environmental temperature when at rest, were inoculated in the foot-pad. Foot-pad infections were observed but no systemic disease. The bats could be maintained for only short periods, however. Poikilothermic animals were studied. Deep body temperatures were found to be nearly identical with ambient temperature. A total of 50 species of reptiles, amphibians, and fish were infected intraperitoneally in a number of experiments, as animals were available. Susceptibility to M. marinum was found throughout these species. There was no tendency to peripheral involvement. In experiments to determine the optimal environmental temperature for infection, cricket frogs (Acris), American chameleons (Anolis), young garter snakes (Thamnophis), and the young of three species of turtles were inoculated intraperitoneally. The optimal temperature for infection was found to be 30 C in each case, and infections at 20 C were definitely slower. The generation time of M. marinum in American chameleons at 30 C was about 19 hr; at 20 C, it was about 46 hr; and, at 10 C, the bacilli did not apparently multiply. Transmission studies revealed instances where infected animals shed M. marinum into the waters in which they were kept, and where animals became infected from water containing M. marinum.

Amphibians↗
PubMed1964

MORPHOGENESIS.

Explore the source record for details and available documents.

Amphibians↗