Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Krypton”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,549 records · Page 86Linked to original sources
PubMed1975

Simultaneous counting of 85Kr in lung and myocardium during measurement of coronary blood flow.

Coronary blood flow rate (ml-min-1-100 g-1) was estimated by a) measuring pump flow into the cannulated circumflex branch of the left coronary artery and dividing by the weight of perfused myocardium and b) measuring the clearance of 85Kr following intra-arterial injection (detection with a 2-in. crystal with cylindrical collimation). Although the correlation between the two measurements was relatively high (r equals 0.90), the line best fitting the data was 85Kr flow equals 0.55 pump flow + 25.6. We tested the possibility that the discrepancy between the two methods was primarily due to the counting of 85Kr removed from myocardium and delivered to lung. Relative efficiency of lung counting versus myocardial counting was determined as well as clearance pattern of 85Kr from lung in each dog. A simple mathematical model which assumes no recirculation of 85Kr to heart allowed correction of coronary clearance curves using this information. When corrected 85Kr flow equals 1.00 pump flow + 4.1 (r equals 0.90). Thus, the major systematic cause for the discrepancy between the two measurements under the conditions of this experiment appears to be simultaneous counting of 85Kr in lung and in myocardium.

Adenosine↗
PubMed2000

Sequential V(A)/Q distributions in the normal rabbit by micropore membrane inlet mass spectrometry.

We developed micropore membrane inlet mass spectrometer (MMIMS) probes to rapidly measure inert-gas partial pressures in small blood samples. The mass spectrometer output was linearly related to inert-gas partial pressure (r(2) of 0.996-1.000) and was nearly independent of large variations in inert-gas solubility in liquid samples. We infused six inert gases into five pentobarbital-anesthetized New Zealand rabbits and used the MMIMS system to measure inert-gas partial pressures in systemic and pulmonary arterial blood and in mixed expired gas samples. The retention and excretion data were transformed into distributions of ventilation-to-perfusion ratios (V(A)/Q) with the use of linear regression techniques. Distributions of V(A)/Q were unimodal and broad, consistent with prior reports in the normal rabbit. Total blood sample volume for each VA/Q distribution was 4 ml, and analysis time was 8 min. MMIMS provides a convenient method to perform the multiple inert-gas elimination technique rapidly and with small blood sample volumes.

Acetone↗