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381.
V. Csanyi A. Doka C. Castellano S. Puglisi-Allegra A. Oliverio 《Behavioural processes》1984,9(4):315-321
The behavioural effects of morphine on fish (Macropodus opercularis) were studied by an ethopharmacological analysis. For this purpose active and passive behavioural units were observed.The results show that morphine treatment had a stimulating effect. However, the treatment resulted not in a general enhancement of active behavioural units, but in a selective increase of some of them, such as swimming and erratic behaviour, or in stereotyped behaviours, such as circling. By contrast, high dosages of morphine resulted in a decrease of escape and of standing under the surface behaviours. 相似文献
382.
V. Carunchio P. Castellano A.M. Girelli A. Messina 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,689(2):1135
A simple high-performance liquid chromatography (HPLC) assay for the simultaneous determination of guanase and aspartate aminotransferase (AST) activities in a single serum sample is described. The method is based on direct detection of enzymatically formed products xanthine and glutamate, respectively. The procedure is sensitive, precise (C.V. below 2% for guanase and 3% for AST), suitable for routine purposes and requires only 100 μl of sample. Kinetic measurements have shown the guanase activity to have an apparent Michaelis constant of 24.5 μM and the AST activity of 11.1 and 0.18 mM for aspartate and oxoglutarate, respectively, at 37°C in Tris-HCl buffer (pH 7.5). 相似文献
383.
José Miguel Mancheño Estíbaliz Atondo Julen Tomás-Cortázar José Luís Lavín Laura Plaza-Vinuesa Itziar Martín-Ruiz Diego Barriales Ainhoa Palacios Claudio Daniel Navo Leticia Sampedro Ainize Peña-Cearra Miguel Ángel Pascual-Itoiz Janire Castelo Ana Carreras-González Donatello Castellana Aize Pellón Susana Delgado Patricia Ruas-Madiedo Blanca de las Rivas Leticia Abecia Rosario Muñoz Gonzalo Jiménez-Osés Juan Anguita Héctor Rodríguez 《Microbial biotechnology》2022,15(2):648-667
Colorectal cancer pathogenesis and progression is associated with the presence of Fusobacterium nucleatum and the reduction of acetylated derivatives of spermidine, as well as dietary components such as tannin-rich foods. We show that a new tannase orthologue of F. nucleatum (TanBFnn) has significant structural differences with its Lactobacillus plantarum counterpart affecting the flap covering the active site and the accessibility of substrates. Crystallographic and molecular dynamics analysis revealed binding of polyamines to a small cavity that connects the active site with the bulk solvent which interact with catalytically indispensable residues. As a result, spermidine and its derivatives, particularly N8-acetylated spermidine, inhibit the hydrolytic activity of TanBFnn and increase the toxicity of gallotannins to F. nucleatum. Our results support a model in which the balance between the detoxicant activity of TanBFnn and the presence of metabolic inhibitors can dictate either conducive or unfavourable conditions for the survival of F. nucleatum. 相似文献
384.
Roberto Rivabene Alfredo Cantafora Chong Chao Yan Flavia Castellano Giovannella Bruscalupi Elena Bravo 《Bioscience reports》1992,12(5):425-432
The effects of HDL1 lipoprotein infusion on biliary lipid secretion were studied in thein vitro model of rat perfused liver. A strong increase in bile flow was observed during and after lipoprotein infusion. This caused a significant rise in cholesterol, phospholipid and bile salt secretions. However, only the percentage of cholesterol increased with respect to the other bile lipids. The changes observed in the cholesterol/phospholipid molar ratio values of liver membrane subfractions (i.e., liver plasma membrane, mitochondria plus lysosomes and microsomes) isolated from the perfused rat liver after HDL1 administration were not significant. 相似文献
385.
386.
Group-specific component (Gc) polymorphism was investigated in 559 individuals from Aragon. The gene frequencies were compared to those reported for other European populations. 相似文献
387.
JoséS. Casas Eduardo E. Castellano María C. Rodríguez-Argüelles Agustín Sánchez José Sordo Julio Zukerman-Schpector 《Inorganica chimica acta》1997,260(2):4059-188
The title compoud, [TlMe2(HL)(H2O)] (HL = monoanion of pyridoxal thiosemicarbazone), crystallizers in the triclinic space group
, No. 2). The HL−anion coordinates to the thallium atom, in an unusual mode through the S atom (Tl-S = 2.832(1) Å), and also forms a weak bond with the metal atom of a neighbouring molecule to make an asymmetric bridge (Tl′…S = 3.190(1) Å). The acidic proton retained in the thiosemicarbazonato anion is located on the oxygen of the phenolic hydroxyl group. The water molecule is only 2.630(4) Å from the metal, suggesting a rather strong bond that contrasts with the long distance between the thallium and the phenolic oxygen (Tl…O(1)′ = 3.124(4) Å). If both strong and weak intermolecular interactions are taken in account, the metal has distorted octahedral coordination with the methyl groups in apical positions. The solid state IR spectrum and 1H, 13C and 205Tl NMR spectra in DMSO solution are also discussed. 相似文献
388.