1,721,055 research outputs found
Conversion of Enkephalin and Dermorphin into δ‐Selective Opioid Antagonists by Single‐Residue Substitution
No full textThe properties of di- and tri-peptides containing 1,2,3,6tetrahydroisoquinoline-3-carboxyliacc id
(Tic) in second position suggest that the message domain of opioid peptides can be composed of
only two residues [Temussi, P. A., Salvadori, S., Amodeo, P., Guerrini, R., Tomatis, R., Lazarus, L.
H., Picone, D. & Tancredi, T. (1994) Biochem. Biophys. Res. Commun. 198, 933-9391. As a crucial
test of the possibility that the Tyr-Tic segment be a message domain in longer peptide sequences,
we have inserted it in the sequences of two typical opioid peptides: [Leulenkephalin, a non-selective
agonist, and dermorphin, a selective p agonist. Here we report the synthesis and biological activity
of [~-Tic’]enkephalin, [~-Tic~]dermorphi[n~,- Tic’]dermorphin carboxylic acid and [~-Tic’]dermorphin:
all [L-Tic’lpeptides were converted from agonists to &selective antagonists. The NMR conformational
study in a dimethylsulfoxide/water cryoprotective mixture at low temperature shows diagnostic
side-chain-side-chain NOES in the spectra of all [~-Tic’]peptides and hints that the 90”
arrangement of the the two aromatic rings found in the cis-Tyr-L-Tic moiety, typical of N-methyl
naltrindole and other 6-selective opiate antagonists, is responsible for the antagonist activity of all
these peptides
I livelli di tiocanatonel siero quale misura oggettiva del consumo di tabacco: relazione con le abitudini al fumo di sigaretta
No full textA MICROSCOPIC APPROACH TO THE STRUCTURE AND THERMODYNAMIC PROPERTIES OF PEPTIDES AND PROTEINS
No full textA NEW GENERAL-FORM OF MOLECULAR-FORCE FIELDS - APPLICATION TO INTRARESIDUE AND INTERRESIDUE INTERACTIONS IN PEPTIDES
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
STABILITY AND STRUCTURE OF FORMAMIDE AND UREA DIMERS IN AQUEOUS-SOLUTION - A THEORETICAL-STUDY
No full text- …
