0000000000323332
AUTHOR
W. Erdmann
Local H2-Clearance and PO2-Measurements in Microareas of the Brain Tissue in Rats
Lubbers [5], as well as others, measured the oxygen partial pressure of the exposed cerebral cortex by means of small platinum microelectrodes. They registered low pO2 values between 1 and 3 mmHg in certain areas of the cortex, despite the fact that the EEG was of normal pattern. In order to decide whether these low pO2 values are a result of low rCBF, or high local oxygen consumption of brain tissue, we developed a new method. Using the same platinum needle, we measured both local pO2 values and H2-clearance curves in microareas of the brain tissue. Cater and Silver [2], Lubbers [4, 5], and others used glass-insulated platinum microelectrodes to measure local pO2. Further, Aukland, Bower a…
A System of <m:math display='block'><m:mrow><m:mi>P</m:mi><m:msub><m:mi>a</m:mi><m:mrow><m:msub><m:mi>O</m:mi><m:mn>2</m:mn></m:msub></m:mrow></m:msub></m:mrow></m:math> $$P{a_{{O_2}}}$$ Continuously Controlled Ventilation
A newly developed system of \(P{a_{{O_2}}}\)-controlled automatic ventilation is reported on. \({P_{{O_2}}}\) microelectrodes (Beckman, IBC) are used to measure arterial \({P_{{O_2}}}\) continuously. In a feedback control system the inspiratory O2 concentration of a respirator is adjusted as long as the set point and actual value of the arterial \({P_{{O_2}}}\) correspond. The functional behavior of the feedback control system is described.
Oxygen-carrying v. non-oxygen-carrying colloidal blood substitutes in schock
Loss of more than 10-15 per cent of the circulating blood causes a corresponding fall in filling pressure and a marked reduction in minute volume. In order to combat a fall in the minute volume, catecholamines are liberated, the stimulating components of these cause a rise in vessel tone. In spite of the blood volume being reduced by blood loss, filling pressure and minute volume are restored by compensating mechanisms as long as the volume lost is not enough to exceed the autoregulative capacity. Even with a blood loss of 10-15 per cent, full compensation is not achieved without replenishing the blood volume unless the fluid lost from the vascular bed is less than I0 per cent of the total.…
Measurement of thett¯production cross section inpp¯collisions ats=1.96 TeVusing soft electronb-tagging
The authors present a measurement of the t{bar t} production cross section using events with one charged lepton and jets from p{bar p} collisions at a center-of-mass energy of 1.96 TeV. A b-tagging algorithm based on the probability of displaced tracks coming from the event interaction vertex is applied to identify b quarks from top decay. Using 318 pb{sup -1} of data collected with the CDF II detector, they measure the t{bar t} production cross section in events with at least one restrictive (tight) b-tagged jet and obtain 8.9{sub -1.0}{sup +1.0}(stat.){sub -1.0}{sup +1.1}(syst.) pb. The cross section value assumes a top quark mass of m{sub t} is presented in the paper. This result is cons…
Local hydrogen-clearance and 257-01257-01257-01- measurements in micro-areas of the rat brain
La pression partielle de l'oxygene et la «clearance» de l'hydrogene ont ete mesurees dans des regions circonscrites. Les deux valeurs sont enregistrees par la meme microelectrode de platine (diametre de la pointe 10μ). Cette methode nouvelle est appliquee dans des experiences faites sur le cerveau de Rats narcotises et on est capable d'evaluer les inhomogenites locales de l'apport d'oxygene dependant du flux du sang.