Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Hemodynamics of the carotid sinus reflex elicited by bilateral carotid occlusion in the conscious dog (1971)
    Springer
    Pflügers Archiv 327 (1971), S. 203-224 
    Details
    ISSN: 1432-2013
    Keywords: Pressoreceptors ; Cardiac Output ; Blood Pressure ; Autoregulation ; Sympatholytics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Flow velocity in the ascending aorta and aortic blood pressure were recorded continuously in healthy conscious dogs. Using implanted pneumatic cuffs the effect of bilateral carotid occlusion on heart rate, stroke volume, cardiac output, peak velocity, maximum acceleration, blood pressure, and total peripheral resistance (T.P.R.) was studied in the resting animal. Following carotid occlusion heart rate rose within 3–4 sec by 13 beats/min; during the steady state it exceeded the control by 8 beats/min. Cardiac output closely followed heart rate, since stroke volume decreased slightly (3–4%), mainly because of the elevated aortic pressure. During the first 3–4 sec cardiac output increased by 10–15% reaching a steady state level 8% above control. The initial fast increase of cardiac output caused mean aortic pressure to rise rapidly, while T.P.R. transiently decreased. Subsequently T.P.R. rose, causing a secondary slow increase of pressure. During the steady state blood pressure was elevated by 27 mm Hg (26%), T.P.R. by 12.1 mm Hg×l−1×min (20%). Maximum acceleration did not change with heart rate and was hardly affected (−1.5%) by the pressure rise. Peak velocity was little influenced by heart rate; it decreased by 7% mainly because of the elevated aortic pressure. β-blockade (0.5 mg/kg propranolol) affected T.P.R. only during control (+18%), but did not modify the time course of the reflex and its steady state changes. α-blockade (5.0 mg/kg phenoxybenzamine) decreased aortic mean pressure (5 mm Hg) and T.P.R. (7%) during control. Following carotid occlusion T.P.R. rose by the same amount, but much more slowly. Starting from the lower control the same pressure level was now obtained by a higher reflex increase of heart rate and cardiac output. It is concluded that the initial pressor response is initiated by an increase of cardiac output mediated by vagal inhibition. The secondary rise of blood pressure is predominantly caused by an increase of T.P.R. due to autoregulation in some vascular beds. The higher stroke work during the reflex is not accomplished by an increased contractility due to sympathetic activation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00586859
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Das Proteinmuster der Ductus thoracicus-Lymphe von Normalpersonen und Patienten mit Lebercirrhose (1972)
    Springer
    Journal of molecular medicine 50 (1972), S. 86-91 
    Details
    ISSN: 1432-1440
    Keywords: Lymph ; Proteins ; Immunoglobulins ; Isoenzymes ; Peptides ; Lymphe ; Proteine ; Immunglobuline ; Isoenzyme ; Peptide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Proteine aus Ductus thoracicus-Lymphe von 7 Patienten mit Lebercirrhose wurden mit Blutseren derselben Patienten sowie mit Lymph- und Blutseren von Normalpersonen nach Konzentration, elektrophoretischem Verhalten im Polyacrylamidgel, immunologischen Eigenschaften und Enzymgehalt verglichen. Auffallend war in den Lymphseren ein relativ geringer IgM-Gehalt, ein teilweise erhöhter IgA-Gehalt, eine hohe Albuminkonzentration, ein lebertypisches LDH-Isoenzymmuster, in 2 Lymphseren das Vorkommen eines lebereigenen Proteins und in einigen pathologischen Lymphseren das Auftreten eines Glykopeptids in hoher Konzentration.
    Notes: Summary The proteins of the thoracic duct lymph and blood serum from seven patients with liver cirrhosis and from normal persons were characterized by protein determination, electrophoresis on polyacrylamid gel, as well as by immunological and enzymatic methods. Differences between lymph and blood sera were observed. The lymph sera showed a low IgM content, a partially elevated IgA content, high albumin concentration, and altered LDH-isoenzyme pattern. In some lymph sera high concentrations of soluble protein from the liver and a glycopeptide were found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01484815
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Der Einfluß einer konstanten Herzfrequenz auf den Carotis-Sinus-Reflex am wachen Hund (1972)
    Springer
    Pflügers Archiv 337 (1972), S. 59-70 
    Details
    ISSN: 1432-2013
    Keywords: Pressoreceptors ; Parasympatholytics ; Pacemaker, Artificial ; Cardiac Output ; Vascular Resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In healty, conscious dogs the heart rate was kept constant at 144 to 146 beats per minute either by vagal blockade with Atropine (0,5 mg/kg i.v.) or by electrical pacing of the heart. In the resting dog a carotid-sinus-reflex was elicited clamping both common carotid arteries with implanted pneumatic cuffs. Velocity in the ascending aorta (electromagnetic flowmeter), pressure in the descending thoracic aorta (implanted miniature pressure transducer) and pressure in the right carotid sinus using a catheter were measured. By analogue processing acceleration in the ascending aorta, stroke volume and stroke work of the left ventricle, and mean values were derived. Compared to the reflex under normal resting heart rates (64 beats per minute) the results show, that with a constant heart rate (144–146 beats per minute) blood pressure rises by about the same amount induced by a larger increase of the peripheral resistance. Because the fast increase of cardiac output regularly observed under normal conditions was eliminated, the time course of pressure elevation was slower when heart rate was kept constant. The elevated stroke work of the left ventricle during carotid occlusion cannot be explained by an increase of contractility due to enhanced sympathetic activity, because no such increase in contractility was found. It is suggested, that a low control heart rate allows fast reflex adjustment of blood pressure mediated by increases of cardiac output due to vagal inhibition. In contrast, when heart rate is high due to vagal blockade or electrical pacing, the reflex response is determined by slow changes of the total peripheral resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00587873
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...