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Anuran metamorphosis experiments with regard to age- and hormonal conditions


, : Anuran metamorphosis experiments with regard to age- and hormonal conditions. Atti R Accad Naz Lincei Rend Cl Sci Fis Mat E Nat 18(5/6): 237-241

Preliminary report. Do the lytic, metamorphogenic substances operate only in the region of metamorphosis? Do they operate regardless of the substratum, or is this latter in a peculiarly favoring condition? Transplants were made from the tails of very young donors to hosts approaching metamorphosis. Does metamorphosis induced by thyroid-extract involve both normal structures and transplants regardless of their respective age-condition and location of graft? Both embryos and larvae were used. Results: Transplants, embryonic or larval, to hosts of the same age metamorphose normally and coincidentally, even if abnormally placed. All tissues were involved. If the donor be slightly younger, metamorphosis still is synchronous. With increasing age-discrepancy (larvae), tendency to synchronism diminishes but does not completely disappear. The lytic substances must be ubiquitous, and there must be peculiarly favoring conditions in the substratum. Thyroid-extract hastens metamorphosis in host and graft, regardless of respective age-condition, tending to eliminate age-discrepancy.

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Chen, L.H., 1984: Sweet potato production systems modeling. A simulation model was developed to determine the planting initiation date and harvest initiation date as affected by total planted area and transplanter-harvester capacity. The simulated yield per unit area decreases almost linearly with respect...

Powers, M.K.; Easter, S.S.Jr, 1978: Behavioral confirmation of the silent period during adaptation to bright lights. The "silent period" is an interval of time following the onset of an intense background during which there is absolute refractoriness to incremental light stimuli. This note provides further confirmations of the existence of the silent p...

Doguoglu, A.; Boni, R.; Burg, G.; Dummer, R.; Schafer, B.W.; Ily, E.; Heizmann, C.W., 1996: Evaluation of the expression of Ca-2+-binding proteins of the S100 family in primary cutaneous melanoma. Journal of Cutaneous Pathology 23(1): 72

Li, L.; Cao, Z.; Jia, P.; Wang, Z., 2010: Calcium signals and caspase-12 participated in paraoxon-induced apoptosis in EL4 cells. In order to investigate whether calcium signals participate in paraoxon (POX)-induced apoptosis in EL4 cells, real-time laser scanning confocal microscopy (LSCM) was used to detect Ca(2+) changes during the POX application. Apoptotic rates of EL4...

Jarlov, N.; Koefoed, F., 1984: Dermatophilosis in the horse. Occurrence in Denmark. Dermatophilus congolensis was identified microscopically in skin scrapings from 6 of 22 horses with acute or chronic encrusted skin lesions, examined in Jylland and Sjaelland. Details of the 6 horses and of biochemical tests and histological stain...

Nikolov, R., 1972: Development of a Bulgarian dairy-type ewe in Sofia region and district. Efforts to increase milk production of the recently formed Semifinewool breed are considered with particular reference to introduction of East Friesian blood. For 6 farms, the mean 1st lactation milk yields of East Friesian crosses ranged from 65....

Havelka, P.; Riedes, N., 1979: Zwei seltene Chironomiden im Oberrheingebiet und ihre rasterelektronemmikroskopische charakterisierung (Xenopelopia nigricans Fittkau und X. falcigera Kiefer). Beitraege Zur Naturkundlichen Forschung In Suedwestdeutschland: 38: 125-129

Jones, M.A.; Johnson, J.C.; French, M.L.; Hart, J.B.; Ritter, M.A., 1972: Unidirectional air flow and surgical face mask exhaust system in the prevention of airborne surgical infection. American Journal of Surgery 124(1): 49-51

Shi, J.; Shen, C.; Dreizen, P., 2000: Role of the essential light chain in the fast-muscle actin-S1 crossbridge cycle II The ADP-vanadate transition state. Biophysical Journal 78(1 Part 2): 235A, Jan

David Lagunoff; Dov H.P.uznik; Leo Sachs, 1966: The cloning of macrophages in agar Identification of the cells by electron microscopy. A normal cell type that can be cloned in agar has been identified by electron microscopy as a macrophage.