Results 281 to 290 of about 20,405 (323)

Dihydroxyphenylalanine in Extrapyramidal Disease

JAMA: The Journal of the American Medical Association, 1963
EVIDENCE has been accumulating for the past several years which has implicated dopamine metabolism in the production of extrapyramidal symptoms. Drugs such as reserpine which tend to produce extrapyramidal symptoms as a side effect have been shown to deplete dopamine from the brain.
A J, FRIEDHOFF, L, HEKIMIAN, M, ALPERT, E, TOBACH   +3 more
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Neuronal Source of Plasma Dihydroxyphenylalanine

The Journal of Clinical Endocrinology & Metabolism, 1987
The source and significance of plasma levels of dihydroxyphenylalanine (DOPA), the precursor of the endogenous catecholamines, have been unknown. We measured arterial and venous plasma DOPA concentrations in healthy subjects at rest, patients who had undergone regional sympathectomies or were undergoing general anesthesia, and subjects during ...
DAVID S. GOLDSTEIN, ROBERT UDELSMAN, GRAEME EISENHOFER, ROBIN STULL, HARRY R. KEISER, IRWIN J. KOPIN, CAROL JOAN FOLIO   +6 more
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Decarboxylation of 3,4-dihydroxyphenylalanine by oxyhemoglobin

Biochemical and Biophysical Research Communications, 1972
Abstract A lysate of red blood cells catalyzes the decarboxylation of 3,4-dihydroxyphenylalanine. This activity appears to be due to a reaction with oxyhemoglobin and not the presence of aromatic L amino acid decarboxylase in erythrocytes.
H, Yamabe, W, Lovenberg
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Dihydroxyphenylalanine secretion in a malignant pheochromocytoma

The American Journal of Medicine, 1967
Abstract Studies on catecholamine metabolism in patients with neural crest tumors revealed a high plasma level of 3,4-dihydroxyphenylalanine (dopa) and dopamine (DM) in association with a malignant, but not a benign pheochromocytoma. The large amounts of these amines may have been mistaken in other studies for norepinephrine because of the use of a ...
A H, Anton, M, Greer, D F, Sayre, C M, Williams   +3 more
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Syntheses of α-ethynyl-3, 4-dihydroxyphenylalanine and α-vinyl-3, 4-dihydroxyphenylalanine

Tetrahedron Letters, 1977
3,4-Dihydroxy-benzoesaureester (I) liefert mit Diphenyldichlormethan den cyclischen Ester (II), der nach Reduktion zum Carbinol (IIIa) ein Benzylchlorid (IIIb) gibt, das mit dem Acetylen-imin (IV) zu einem Substitutionsprodukt (V) fuhrt.
D. Taub, A.A. Patchett
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3, 4-Dihydroxyphenylalanine and Related Compounds

1966
This review covers essentially derivatives of β-phenyl-α-alanine which contain two phenolic hydroxyl groups, and some of their analogs and derivatives. They comprise β-(3, 4-dihydroxyphenyl)-α-alanine (dopa) and the few known ethers and ring substituted derivatives of this amino acid, as well as derivatives of dopa substituted in the alanine group ...
A R, Patel, A, Burger
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Origin and Significance of Plasma Dihydroxyphenylalanine

1997
Publisher Summary This chapter summarizes the origin and the significance of plasma 3,4-Dihydroxyphenylalanine (DOPA). DOPA is both a catecholamine and an aromatic amino acid. DOPA occupies a central position in the function of the sympathetic nervous system. It is the immediate product of the rate-limiting step in the biosynthesis of catecholamines:
Eldrup, Ebbe, Richter, Erik A., Hetland, Merete L., Andreasen, Jan, Hilsted, Jannik, Møller, Svend E., Christensen, Niels Juel   +6 more
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Radical sequestration by protein-bound 3,4-dihydroxyphenylalanine

The International Journal of Biochemistry & Cell Biology, 2010
Protein-bound 3,4-dihydroxyphenylalanine (PB-DOPA), a redox-active product of protein oxidation, is capable of functioning as both a pro- and antioxidant. A number of in vitro and in vivo studies have demonstrated a toxic, non-toxic or even beneficial effect of free DOPA, however little investigation has examined the physiological activity of PB-DOPA ...
Nelson, Michelle, Foxwell, Alice R., Tyrer, Peter, Dean, Roger T.   +3 more
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Clinical experience with dihydroxyphenylalanine (DOPA) in depression

Journal of Psychiatric Research, 1963
THIS is a report of the rGsults of a clinical trial of dihydroxyphenylalanine (DOPA), a precursor of catechol amines, in the treatment of depression. This experiment was undertaken as an indirect test of the catechol amine theory of affective disorders, which proposes that depressed patients have an absolute or relative deficiency of central nervous ...
G L, KLERMAN, J J, SCHILDKRAUT, L L, HASENBUSH, M, GREENBLATT, D G, FRIEND   +4 more
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ChemInform Abstract: SYNTHESES OF α‐ETHYNYL‐3,4‐DIHYDROXYPHENYLALANINE AND α‐VINYL‐3,4‐DIHYDROXYPHENYLALANINE

Chemischer Informationsdienst, 1977
Abstract3,4‐Dihydroxy‐benzoesäureester (I) liefert mit Diphenyldichlormethan den cyclischen Ester (II), der nach Reduktion zum Carbinol (IIIa) ein Benzylchlorid (IIIb) gibt, das mit dem Acetylen‐imin (IV) zu einem Substitutionsprodukt (V) führt.
D. TAUB, A. A. PATCHETT
openaire   +1 more source