Now showing items 541-560 of 2801

    • Capparelli, Mario V.; DeSanctis, Y.; Arce, A. J.; Spodine Spiridonova, Evgenia (MUNKSGAARD INT PUBL LTD, 1997-03-15)
      The reaction of 1,2,3-triphenylphosphirene with [H2Os3-(CO)(10)] leads to the title compound, [Os-3(CO)(9){(C6H5)(3)-C2PO}], which displays an open Os-3(CO)(9) cluster [Os-Os 2.703(1) and 2.867(2) Angstrom, and Os-Os-Os ...
    • Díaz, René; Sapag, Amalia; Peirano, Alessandra; Steiner, Jeannette; Eyzaguirre, Jaime (ELSEVIER SCIENCE BV, 1997-03-18)
      The cDNA, for xylanase B from Penicillium purpurogenum was cloned and sequenced. This DNA encodes a protein of 208 amino acids which is expected to yield a protein of 183 residues upon processing of the N terminus. The ...
    • Bustamante Araya, Ramiro; Toral Ponce, María; Richter Duk, Pablo; Serey Estay, Italo; Yates, L. R. (KLUWER ACADEMIC PUBL, 1997-05)
      Copper mining activities are very important in central Chile. Like other metals, copper is a nutrient for most plants at low concentration levels; however, at higher levels it may become toxic. At present, copper abundance ...
    • Prieto, Humberto; Chiong Lay, Mario; Garrido, Jorge; Seelenfreund Hirsch, Daniela; Quaas, Alex; Pérez Roepke, Luz María (GUSTAV FISCHER VERLAG, 1997-05)
      A light-dependent bleaching of plastids was induced in lemon seedlings through cultivation in the presence of the herbicide Norfluorazon (NFZ). Also, etiolated seedlings were obtained by cultivation under continuous dark ...
    • Sapag, Amalia; Draper, D. E. (PERGAMON-ELSEVIER SCIENCE LTD, 1997-06)
      A minimum of 460 nucleotides of 16S ribosomal RNA are needed to fold the target site for E. coli ribosomal protein S4, although a much smaller region within this large domain is protected from chemical reagents by the ...
    • García, R.; Lemus Gutiérrez, Igor; Rivera, P.; Erazo, Silvia (ELSEVIER SCI IRELAND LTD, 1997-07)
      The methanolic extract of the aerial portion of Chenopodium chilense Schrad., used in Chilean traditional medicine as a remedy for stomach-ache, has been found to exert the major spasmolytic activity in acetylcholine ...
    • Erazo, Silvia; García, R.; Backhouse Erazo, Nadine; Lemus Gutiérrez, Igor; Delporte Vergara, Carla; Andrade, C. (ELSEVIER SCI IRELAND LTD, 1997-07)
      The anti-inflammatory property of Lomatia hirsuta (Lam.) Diels ex Macbr. (Proteaceae), leaves (radal), a plant used in Chilean traditional medicine for bronchial troubles and asthma, was evaluated. The biological assays ...
    • Toral, A. E.; Tapia, A. E.; Richter Duk, Pablo; Fuenzalida, Emely (ROYAL SOC CHEMISTRY, 1997-10)
      A flow injection photometric method for the sequential determination of zinc and copper in mixtures was developed based on the variation of the stability of the chromogenic complexes between the analytes and the reagent ...
    • Cordano, G.; Ferreira, José Roberto; Muñoz, S.; Rivera, E.; Pavani, Mario; Pavez, H. (SOCIEDAD CHILENA DE QUIMICA, 1997-12)
      We report the reaction of gallic acid with chloroacetic acid and three equivalents of sodium hydroxide. In this reaction, 2,6-dihydroxy-4-carboxyphenoxyacetic acid (A) is produced instead of 2,3-dihydroxy-5-carboxyphenoxyacetic ...
    • Erazo, Silvia; González, V.; Zaldívar San Román, María Mercedes; Negrete Córdova, Rosa (SWETS ZEITLINGER PUBLISHERS, 1997-12)
      Antimicrobial activity of leaf extracts of Psoralea glandulosa L. (Papilionaceae) is reported This study was carried out on the extracts and on the plant's most abundant metabolite, bakuchiol. Antimicrobial activity against ...
    • Ahumada Torres, Aída Inés de Lourdes; Schalscha B., Eduardo; Soto, R. (SOCIEDAD CHILENA DE QUIMICA, 1997-12)
      The applicability, sensitivity and repetitivity, as well as general aspects of the Capillary Zone Electrophoresis (CZE) technique was studied as applied in the identification and quantification of Cl-, NO3-, HCO3-, SO42-, ...
    • Weiss López, Boris; Saldaño Hurtado, Danilo; Araya Maturana, Ramiro; Gamboa, Consuelo (AMER CHEMICAL SOC, 1997-12-24)
      Deuterium quadrupole splittings from the aromatic ring of a series of linear benzyl-d(5) alkyl ethers, with alkyl chain length from 1 to 15 carbon atoms, have been measured using H-2-NMR spectroscopy. These molecules, 20% ...
    • Núñez Vergara, Luis; Bollo Dragnic, Soledad; Olea Azar, Claudio; Santander, Paola; Gunckel, Soledad; Squella Serrano, Juan (Sociedad Chilena de Química, 1998)
      This paper reports the scavenging of the nitro radical anion of nisoldipine by N-acetylcysteine assessed by cyclic volatammetry (CV) and EPR spectroscopic techniques. Studies by CV on the reactivity of the radical were ...
    • Zanocco Loyola, Antonio; Günther Sapunar, Germán; Fuente, J. R. de la; Lemp Miranda, Else; Pizarro U., N. (1998)
      Detection of O,('A,) phosphorescence emission, A,,,, = 1270 nm, following laser excitation and steady-state competitive methods was employed to measure total rate constants, k,, for the reactions of the diuretic furosemide, ...
    • Jaque, Pablo; Toral Ponce, María; Richter Duk, Pablo (Sociedad Chilena de Química, 1998)
      En este trabajo se desarrolla un método de análisis por inyección de flujo (FIA) para la determinación de ranitidina en formas farmacéuticas y orina, empleando una celda de flujo polarográfica como sistema de detección, ...
    • Zanocco Loyola, Antonio; Günther Sapunar, Germán; Lemp Miranda, Else; Lissi Gervaso, Eduardo A. (1998)
      The cationic dye Methylene Blue included in the internal aqueous microphase of dioctadecyldimethylammonium chloride (DODAC) vesicle shows the typical monomer–dimer equilibrium observed in homogenous aqueous solutions. ...
    • Soto Bustamante, Eduardo; Galyametdinov, Y.; Griesar, K.; Schuhmacher, Elcio; Haase, W. (Hüthig & Wepf Verlag, 1998)
      The synthesis of a novel kind of form-retaining liquid crystalline crosslinked metallopolymer is reported. Copper(II) is complexed by Schiff's base units as part of a mesogenic side chain polymer. This leads to remarkable ...
    • Schalscha B., Eduardo; Ahumada Torres, Aída Inés de Lourdes (PERGAMON-ELSEVIER SCIENCE LTD, 1998)
      Industrial and domestic waste waters in Chile are discharged without previous treatment into rivers and other inland waters which are used to irrigate agricultural lands. The present study reports on results obtained when ...
    • Bunel Torrealba, Sergio; Ibarra, Carmen; Moraga, Exequiel; Parada Aliste, José; Blasko, Andrei; Whiddon, Christy; Bunton, Clifford A. (Elsevier, 1998)
      The I3- salts soluble in acetone and sparingly so in methanol, and I3- inhibits formation of Co(II) so that minor decomposition of acomplex does not broaden its 1H NMR signals. The (phen)2 complex of Co(III) with D-glucosamine ...
    • Núñez Vergara, Luis; Díaz Araya, Guillermo; Olea Azar, Claudio; Atria Salas, Ana María; Bollo Dragnic, Soledad; Squella Serrano, Juan (1998)
      Purpose. To determine the formation of the one-electron reduction product from nisoldipine and its reactivity with relevant thiols in mixed medium. Methods. Cyclic voltammetry (CV) and electron paramagnetic resonance (EPR) ...