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  • 1990-1994  (1)
  • 1975-1979  (1)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Basic research in cardiology 73 (1978), S. 1-9 
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Inkubation von sterilem menschlichem Serum oder Plasma bei 37 °C führt zur Entstehung eines nichtdialysablen Faktors, den wir als aktives pressorisches Prinzip (APP) bezeichnet haben. Intravenöse Gabe von inkubiertem Humanserum an narkotisierte gangliengeblockte Ratten ruft eine Blutdruckantwort hervor, die jener auf Angiotensin II und Noradrenalin ähnlich ist. Die pressorische Aktivität von Serum bzw. Plasma ist von Inkubationszeit und Temperatur abhängig. Bei 37 °C wird die maximale Aktivität nach 6 Tagen Inkubation erreicht; weitere Inkubation führt zu einer geringfügigen Aktivitätsabnahme. Bei 4 °C ist selbst nach mehreren Wochen nur wenig APP nachweisbar; bei 25 °C tritt ein Aktivitätsmaximum nach ca. 14 Tagen auf. Inkubation bei 47 °C liefert eine Maximalaktivität nach etwa 48 Studen, gefolgt von einem deutlichen Aktivitätsverlust. Bei Inkubation von Serum bei 37 °C nach Zugabe von Angiotensin II oder Noradrenalin werden diese Substanzen rasch inaktiviert, während die APP-Bildung unbeeinflußt vor sich geht. Nach Gelfiltration auf Sephadex G-200 ist die gesamte pressorische Aktivität in der Fraktion nachzuweisen, der die hauptmenge an Albumin angehört. Es kann daher angenommen werden, daß APP entweder selbst ein Protein ist oder aber eine Substanz, die an ein Trägerprotein gebunden ist. Die Eigenschaften von APP schließen eine Identität mit Angiotensin II oder Noradrenalin aus.
    Notes: Summary Incubation of human serum or plasma at 37°C leads to the formation of a non-dialysable vasoactive factor, which we have called active pressor principle (APP). The intravenous injection of incubated human serum into anesthetized ganglionic blocked rats causes a transient blood pressure increase similar to the response to angiotensin II. The pressure activity of incubated serum or plasma depends on temperature and time of the incubation. At 37 °C the activity reaches a maximum within 6 days. A slight decrease occurs after further incubation. At 4 °C very little APP is formed within several weeks; at 25 °C a maximum is reached after about 14 days of incubation. Incubation at 47 °C yields a maximum activity after 48 hours; further incubation induces a marked decrease in APP-concentration. During incubation of serum at 37 °C after addition of angiotensin II or noradrenaline, these substances are rapidly inactivated, whereas the APP-formation proceeds uninfluenced. After separation by means of gel filtration with
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Polymer bulletin 25 (1991), S. 451-458 
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary Oligomers with different aromatic substituents (oligostyrenes, oligo-p-ethylstyrenes, oligo-p-methoxystyrenes and oligo-1-vinylnaphthalenes) were synthesized by living anionic polymerization using sec-butyllithium as initiator. Number average degrees of polymerization were varied between 2 and 16 and narrow homologuedistributions were obtained. In the case of the benzenic types the isolation into pure homologues from dimers to hexamers was carried out by preparative gel permeation chromatography (GPC). In a polymeranalogous heterogeneous catalytic hydrogenation reaction the aromatic compounds were converted into oligomers with saturated cyclic structures, the initial homologue-distributions not being changed. Characterization of all oligomers was performed by GPC and proton nuclear magnetic resonance (1H-NMR). In the case of oligostyrenes and oligo-p-ethylstyrenes the occurrence of the characteristic high field shift of the ortho-protons is observed in dependence of the degree of polymerization. Oligo-1-vinylnaphthalenes show three differently shielded aromatic resonance areas.
    Type of Medium: Electronic Resource
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