ISSN:
0362-2525
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
The skins of normal and x-rayed tadpoles and frogs were compared. Almost no mitotic figures occurred after the tenth day of larval life. The number of mitoses and the length of the period during which mitosis occurred were reduced by x-rays in proportion to the exposure. Spindle-shaped cells were found on the vertical connective tissue fiber bundles which connect the lower layer of the dermis with the under side of the epidermis in adult frogs. After exposure to 4000 r the number of these cells, which are believed to be traveling up the vertical strands to join the epidermis, was doubled. New, uninjured cells appeared in the basal epidermal layer following this increase. Since no appreciable number of mitotic divisions and no amitotic divisions were found in the epidermis, either normally or during the regeneration following exposure to x-rays, these ‘traveling-cells’ are held to be an important source of replacement in correlation with normal desquamation as well as desquamation caused by the irradiation.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jmor.1050590206
