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
  • First order canal neuron dynamics  (1)
  • Intraventrikuläre Blutung  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    International journal of legal medicine 105 (1993), S. 243-245 
    ISSN: 1437-1596
    Keywords: Intraventricular haemorrhage ; Head injury ; Traumatic subarachnoid haemorrhage ; Intraventrikuläre Blutung ; Kopftrauma ; Traumatische Subarachnoidalblutung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Description / Table of Contents: Zusammenfassung Der Fall eines 26 Jahre alten Mannes wird beschrieben, welcher nach einer Episode von Traumen eine tödliche intraventrikuläre Hirnblutung erlitt. Bei der Obduktion wurde nach dem ersten Eindruck eine traumatische Subarachnoidalblutung vermutet, und die anfängliche Untersuchung war daher auf die Strukturen des Halses und auf die Vertebralarterien gerichtet, jedoch mit negativen Resultaten. Die Sektion des fixierten Gehirns zeigte eine massive intraventrikuläre Blutung mit sekundärer Beteiligung des Subarachnoidalraums und Ausbreitung in das Hirnparenchym. Keine Blutungsquellen oder natürliche Erkrankungen der Hirngefäße konnten gefunden werden. Die praktischen Aspekte der Diagnose und der vorsichtige Ansatz, welcher notwendig ist, um Subarachnoidalblutungen zu interpretieren, werden betont. Die Bedeutung der intraventrikulären Blutung nach Trauma ist mit der Einführung der Computertomographie offensichtlicher geworden. Die Implikationen dieses und ähnlicher Fälle werden bedacht.
    Notes: Summary A case of a 26-year-old man who suffered a fatal intraventricular cerebral haemorrhage following an episode of trauma is described. The initial appearance at necropsy suggested a traumatic subarachnoid haemorrhage and initial investigation was directed towards the anterior neck structures and the vertebral arteries with negative results. Dissection of the fixed brain showed a massive intraventricular bleed with secondary involvement of the subarachnoid space and dissection into the cerebral parenchyma. No bleeding points or natural disease of the cerebral vessels could be identified. The practical aspects of diagnosis and the cautious approach necessary in interpreting subarachnoid bleeding is emphasised. The significance of intraventricular haemorrhage following trauma has become more apparent with the advent of computed tomographic scanning. The implications for this and similar cases are considered.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 62 (1986), S. 312-320 
    ISSN: 1432-1106
    Keywords: Isolated frog labyrinth ; Excitatory-inhibitory rotational stimuli ; First order canal neuron dynamics ; Non-linearities
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary EPSPs and spikes were recorded at rest and during rotation from single fibres of the posterior nerve in the isolated frog labyrinth. The spike discharge properties of 57 units were examined at rest and during repetitive acceleratory-velocity steps. Forty of these units were subjected to excitatory steps of 5–12 s duration and 45% displayed an evident discharge adaptation. In the non-adapting units, the excitatory response also deviated from that expected on the basis of the torsion-pendulum model and exhibited an exponential time-course in only 36% of the fibres examined. The time constant T2 of the response rising phase was significantly longer than that of the decay (2.5 s versus 1.7 s). When all the 57 units were considered, a linear behaviour was found in 67%. The average gain in these linear units was 1.9 ± 1.4 spikes · s−1/deg · s−2. Adaptive fibres exhibited a lower resting firing rate and a higher gain (3.8 spikes/s and 2.3 spikes · s−1/deg · s−2, respectively) when compared with the non-adapting ones (7.1 spikes/s and 1.5 spikes · s−1/deg · s−2). An undershoot was present in 57% of the units; it increased with acceleration and was not strictly related to adaptation. Fifteen of the 40 units tested with the 5–12 s duration excitatory steps survived repeated inhibitory accelerations of the same duration. In these units a marked response asymmetry was evident since their resting activity could be abolished by accelerations not larger than 10 deg/s2. In 40% of the units inhibited by acceleration the mean response was proportional to the stimulus logarithm, while the others saturated for weak stimulations. A consistent overshoot of the discharge was evident in most of the units (60%). Analysis of the EPSP emission rates demonstrates that even a 10–20% increase in their frequency during excitation results in a two-three fold increase in the corresponding spike frequency. Similarly, a decrease of 15–35% in their numbers during inhibition is sufficient to completely block the spike firing. These findings reveal the high sensitivity of the afferent synapse, spike discharge being modulated by slight modifications in the release of the excitatory transmitter.
    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...