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
  • Electronic Resource  (2)
  • 1990-1994  (2)
  • Ammonia  (1)
  • Cerebral hemorrhage  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Neuroradiology 34 (1992), S. 301-304 
    ISSN: 1432-1920
    Keywords: 23Na MRI ; 1H MRI ; Cerebral hemorrhage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Four patients with cerebral hemorrhage were examined serially from the acute to chronic phase by1H magnetic resonance imaging (MRI),23Na MRI and computed tomography (CT). At 1–2 days after bleeding, the23Na image revealed no visible signal change in the area of hemorrhage, although CT and1H images clearly demonstrated the existence of a hematoma in the thalamus or putamen. At 4–7 days after the hemorrhage, the23Na images began to exhibit a small increase in signal intensity at the hematoma site, while at 2–3 weeks, a marked increase in23Na signal intensity was observed. These findings suggest that the hematoma consisted mainly of a corpuscular component, with a low Na+ concentration, with little serum component. Lack of signal from the corpuscular component on the23Na image was confirmed by an in vitro study. In the late acute phase, Na+ accumulation may occur in the corpuscular component due to failure of the Na+ pump. The intracellular23Na appears to be totally visible to MRI, resulting in an increase in signal intensity. In the subacute or chronic phase, the corpuscular component may be destroyed, leaving fluid in its place. A high Na+ concentration in this fluid may give markedly increased23Na signal intensity on MRI.23Na MRI appears to provide important information for understanding the evoluation of cerebral hemorrhage and for estimating the viability of cells, although its value for diagnosis may not be great.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1750
    Keywords: Rapidly adapting pulmonary stretch receptor ; Ammonia ; Substance P ; Substance P blocker
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We investigated the effects of the substance P (SP) blocker [D-Pro2,D-Trp7,9]-SP on the response of rapidly adapting pulmonary stretch receptors (RARs) to SP administered into the right atrium, or ammonia vapor inhaled into the lungs in anesthetized, spontaneously breathing rabbits. Right atrial administration of SP (0.3, 1.0, and 3.0 µg/kg) caused an increase in the RAR activity, and this increase became more prominent as the dose of SP was increased. The RARs increased their activity following inhalation of vapor from 5 and 10% ammonia solutions, and the increase was concentration dependent. The excitatory responses of RAR activity to SP at different doses were greatly diminished or completely blocked by administration of the selective SP antagonist (300 and 500 µg/kg). However, the ammonia-induced RAR stimulation was not significantly altered by prior treatment with the SP blocker (300 and 500 µg/kg). These results suggest that the stimulation of RARs by ammonia does not occur as a result of the release of SP from sensory nerves in the airways and lungs.
    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...