Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1985-1989  (32)
  • 1987  (32)
  • Chemistry  (29)
  • SCN−  (2)
  • Computational Chemistry and Molecular Modeling
Material
Years
  • 1985-1989  (32)
Year
  • 1
    ISSN: 1432-1424
    Keywords: gallbladder ; Na+−Cl− symport ; acetazolamide ; SITS ; SCN− ; bumetanide ; K+
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary In the epithelium of rabbit gallbladder, in the nominal absence of bicarbonate, intracellular Cl− activity is about 25mm, about 4 times higher than intracellular Cl− activity at the electrochemical equilibrium. It is essentially not affected by 10−4 m acetazolamide and 10−4 m 4-acetamido-4′-isothiocyanostilbene-2,2′-disulfonate (SITS) even during prolonged exposures; it falls to the equilibrium value by removal of Na+ from the lumen without significant changes of the apical membrane potential difference. Both intracellular Cl− and Na+ activities are decreased by luminal treatment with 25mm SCN−; the initial rates of change are not significantly different. In addition, the initial rates of change of intracellular Cl− activity are not significantly different upon Na+ or Cl− entry block by the appropriate reduction of the concentration of either ion in the luminal solution. Luminal K+ removal or 10−5 m bumetanide do not affect intracellular Cl− and Na+ activities or Cl− influx through the apical membrane. It is concluded that in the absence of bicarbonate NaCl entry is entirely due to a Na+−Cl− symport on a single carrier which, at least under the conditions tested, does not cotransport K+.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1424
    Keywords: gallbladder ; Na+−Cl− cotransport ; acetazolamide ; furosemide ; SITS ; SCN− ; amiloride
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary Cl− influx at the luminal border of the epithelium of rabbit gallbladder was measured by 45-sec exposures to36Cl− and3H-sucrose (as extracellular marker). Its paracellular component was evaluated by the use of 25mm SCN− which immediately and completely inhibits Cl− entry into the cell. Cellular influx was equal to 16.7μeq cm−2 hr−1 and decreased to 8.5μeq cm−2 hr−1 upon removal of HCO 3 − from the bathing media and by bubbling 100% O2 for 45 min. When HCO 3 − was present, cellular influx was again about halved by the action of 10−4 m acetazolamide, 10−5 to 10−4 m furosemide, 10−5 to 10−4 m 4-acetamido-4′-isothiocyanostilbene-2,2′-disulfonate (SITS), 10−3 m amiloride. The effects of furosemide and SITS were tested at different concentrations of the inhibitor and with different exposure times: they were maximal at the concentrations reported above and nonadditive. In turn, the effects of amiloride and SITS were not additive. Acetazolamide reached its maximal action after an exposure of about 2 min. When exogenous HCO 3 − was absent, the residual cellular influx was insensitive to acetazolamide, furosemide and SITS. When exogenous HCO 3 − was present in the salines, Na+ removal from the mucosal side caused a slow decline of cellular Cl− influx; conversely, it immediately abolished cellular Cl− influx in the absence of HCO 3 − . In conclusion, about 50% of cellular influx is sensitive to HCO 3 − , inhibitable by SCN−, acetazolamide, furosemide, SITS and amiloride and furthermore slowly dependent on Na+. The residual cellular influx is insensitive to bicarbonate, inhibitable by SCN−, resistant to acetazolamide, furosemide, SITS and amiloride, and immediately dependent on Na+. Thus, about 50% of apical membrane NaCl influx appears to result from a Na+/H+ and Cl−/HCO 3 − exchange, whereas the residual influx seems to be due to Na+−Cl− contranport on a single carrier. Whether both components are simultaneously present or the latter represents a cellular homeostatic counterreaction to the inhibition of the former is not clear.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 70 (1987), S. 680-689 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Eight cyclic triamines with ring sizes between 9 and 13 were synthesized by the p-toluenesulfonate method. The open-chain triamines bis(2-aminoethyl)amine (dien) and bis(3-aminopropyl)amine (diprop) were used as starting materials. In some cases, the corresponding dimeric cyclic hexaamines have been isolated and characterized as major by-products. The complexation of Cu(I) by the triamines has been studied potentiometrically in CH3CN/H2O. All ligands L form ternary complexes [Cu(CH3CN)L]+. The corresponding association constants vary between 1011 and 107, decreasing with increasing ring size. In addition, complexes [Cu(CH3CN)yLH]2+, y = 1 or 2, are found as less important species with maximum concentrations of 7 to 50%.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Gloeosporone, the germination self-inhibitor from the fungus Colletotrichum gloeosporioides f.sp. jussiaea, is shown by spectroscopic data and X-ray analysis to have the constitution and relative configuration as shown in Formula 2 (either (1S,6R,12R)-1-hydroxy-6-pentyl-5,15-dioxabicyclo[10.2.1]pentadecan-4,13-dione or its enantiomer), rather than the previously assigned constitution 1.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 11-15 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The reaction of MHCl(CO)[P(iPr)3]2, (1, 2) and MHCl-(CO)[PMe(tBu)2]2 (5, 6) with NaBH4 in methanol lead to the octahedral compounds MH(η2-BH4)(CO)[P(iPr)3]2, (3, 4) and MH(η2-BH4)(CO)[PMe(tBu)2]2 (7, 8), which posses a rigid structure in solution only at low temperatures. Above ca. -30°C exchange processes take place which involve the bridging hydrogen atoms and the terminal hydrogens attached to boron but not the metal hydride ligand. The compounds 3 and 4 react with Lewis bases L such as CO, P(OMe)3, PMe3, and P(iPr)3 to form dihydridoruthenium(II) and -osmium(II) complexes MH2(CO)-(L)[P(iPr)3]2 (9 - 15). In the reaction of 4 with methanol under reflux, the tetrahydridoosmium(IV) compound OsH4(CO)[P(i-Pr)3]2 (16) is produced.
    Notes: Die Reaktionen von MHCl(CO)[P(iPr)3]2, (1, 2) und MHCl-(CO)[PMe(tBu)2]2 (5, 6) mit NaBH4 in Methanol führen zu den oktaedrischen Verbindungen MH(η2-BH4)(CO)[P(iPr)3]2, (3, 4) und MH(η2-BH4)(CO)[PMe(tBu)2]2 (7, 8), die in Lösung nur bei tiefer Temperatur eine starre Struktur besitzen. Oberhalb von ca. -30°C finden Austauschprozesse statt, in welche die Brücken-H-Atome und die am Bor endständig gebundenen H-Atome, nicht jedoch der Metall-Hydrid-Ligand, einbezogen sind. Die Verbindungen 3 und 4 reagieren mit Lewis-Basen L wie CO, P(OMe)3, PMe3 und P(iPr)3 zu Dihydridoruthenium(II)- und -osmium(II)-Komplexen des Typs MH2(CO)(L)[P(iPr)3]2 (9-15). Bei Reaktion von 4 in Methanol unter Rückfluß entsteht die Tetrahydridoosmium(IV)-Verbindung OsH4(CO)[P(iPr)3]2 (16).
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 887-898 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Derivatives of silicic acid of the type Si6O5R18 and Si8O7R18 (R = Cl, OCH3, and OC2H5) as well as bicyclic Si8O9(OC2H5)14 were isolated and characterized by 29Si NMR. The spin-lattice-relaxation and the nuclear Overhauser enhancement factor of the esters were determined between 273 and 343 K. The temperature dependency of the dipolar contribution to the longitudinal relaxation time gave an energy of activation for the segmental motion of the siloxane skeleton of about 10 kJ/mol which is independent of the kind of building unit.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 29 (1987), S. 962-968 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An artisanal static process for protein enrichment of cassava by solid-state fermentation, developed in laboratory and tested on pilot units in Burundi (Central Africa), provides enriched cassava containing 10.7% of dry matter protein versus 1% before fermentation. Cassava chips, processed into granules of 2-4-mm diameter, are moistened (40% water content) and steamed. After cooling to 40°C, cassava is mixed with a nutritive solution containing the inoculum (Rhizopus oryzae, strain MUCL 28627) and providing the following per 100 g dry matter: 3.4 g urea, 1.5 g KH2PO4, 0.8 g MgSO4·7H2O, and 22.7 g citric acid. For the fermentation, cassava, with ca. 60% moisture content, is spread in a thin layer (2-3 cm thick) on perforated trays and slid into an aerated humidified enclosure. The incubation lasts ± 65 h. The production of protein enriched cassava is 3.26 kg dry matter/m2 tray. The effects of the variation of the nutritive solution composition and the inoculum conservation period on the protein production are equally discussed.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 33 (1987), S. 503-505 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Biopolymers 26 (1987), S. 1207-1225 
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Prior to availability of the crystal structure of the complex, we evaluated models of the complex between porcine pancreatic elastase and a t-Boc-Val-derived benzoxazinone inhibitor. Models of the noncovalent and covalent complex were generated using computer graphics and each model was subjected to energy minimization using molecular mechanics. After the crystal structure became available, we found that the model with the lowest energy was in good agreement with the crystal structure, except for the position of the His57 side chain. Permissible conformations of the inhibitor were based on information from x-ray crystal structures and an earlier conformational energy investigation of t-Boc-amino acids. We did not, however, limit ourselves to these conformations. The conformation of the inhibitor in the lowest energy model and crystal structure, was not similar to any of the minimum-energy conformations of t-Boc-amino acids. This suggests that limiting proposed binding modes only to the lowest energy conformations of a ligand (prior to binding) may sometimes unfairly bias the procedure.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie in unserer Zeit 21 (1987), S. 59-69 
    ISSN: 0009-2851
    Keywords: Chemistry ; Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Werkstoffe auf der Basis von synthetischen oder natürlichen Polymeren sind in vielen Bereichen des zivilisierten Lebens selbstverständlich geworden. Das liegt unter anderem an den typischen Eigenschaften der Polymeren, z. B. leichte Formgebung, geringes spezifisches Gewicht und oft niedriger Preis, die ihnen im Vergleich zu den „klassischen“ Werkstoffen wie Holz, Metall und Keramik Vorteile verschaffen.Besonders auf dem Gebiet der Konstruktionswerkstoffe verdrängen deshalb Polymere andere Werkstoffe aus immer mehr Anwendungsbereichen. So ist z. B. die Innenausstattung von Personenkraftwagen in den letzten Jahren fast ausnahmslos eine Domäne der polymeren Werkstoffe geworden. Der vorliegende Artikel über Grundlagen und Anwendungen von „Polymer-Legierungen“ ist der erste einer Serie von Aufsätzen, die sich unter der gemeinsamen überschrift „Polymere Werkstoffe“ mit den vielseitigen Aspekten dieser Werkstoffklasse befassen werden und in zwangloser Folge erscheinen sollen.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...