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Biomedical subjects

J Miller

Publications and source records attributed to J Miller.

At least 1,243 records · Page 69Linked to original sources

Immunological competence: alteration by whole body x-irradiation and shielding of selected lymphoid tissues.

The spleen and thymus of 6-week-old mice contain similar numbers of lymphoid cells. A lethal dose of x-irradiation given to animials whose thymus, midgut, or hindlimbs were shielded at the same time resulted in permanent acceptance of allografts, while a similar dose given to spleen-shielded mice so irradiated resulted in a normal rejection pattern. The return of immunological competence was related to the state of the lymphoid organs with different types of shielding.

Animals↗

Inhibition of leaf process by p-fluorophenylalanine during induction of flowering in the cocklebur.

The amino acid antimetabolite, DL-p-fluorophenylalanine (FPA), inhibited induction of flowering in the short-day cocklebur plant, Xanthium pensylvanicum Wall., primarily by interfering with processes occurring during the inductive dark period. At the concentrations used the inhibitor had little effect on subsequent vegetative development of the plant.The inhibition was largely reversed (internally) by L-phenylalanine, but not by D-phenylalanine nor by DL-tyrosine. The FPA strongly inhibited the absorption of labeled phenylalanine, leucine, and glycine, and inhibited the conversion of phenylalanine into protein in experiments where incorporation was separated in time from effects upon absorption. The FPA, too, was incorporated into protein, at nearly half the rate of phenylalanine. Neither D- nor L-phenylalanine significantly interfered with absorption of FPA, showing the FPA did not affect amino acid absorption by simple competition for a common carrier site. It was concluded that FPA may affect flower induction because of its interference with normal enzyme synthesis, although effects on other processes might also be involved.

Antimetabolites↗