scholarly journals Correction for Intravascular Activity in the Oxygen-15 Steady-State Technique is Independent of the Regional Hematocrit

1987 ◽  
Vol 7 (3) ◽  
pp. 372-374 ◽  
Author(s):  
Adriaan A. Lammertsma ◽  
Jean-Claude Baron ◽  
Terry Jones
Keyword(s):  
Carbon Monoxide ◽  
Steady State ◽  
Metabolic Rate ◽  
Molecular Oxygen ◽  
Correction Method ◽  
Large Vessel ◽  
Cerebral Metabolic Rate ◽  
State Technique ◽  
Additional Procedure

The oxygen-15 steady-state technique to measure the regional cerebral metabolic rate for oxygen requires a correction for the nonextracted intravascular molecular oxygen-15. To perform this correction, an additional procedure is carried out using RBCs labeled with 11CO or C15O. The previously reported correction method, however, required knowledge of the regional cerebral to large vessel hematocrit ratio. A closer examination of the underlying model eliminated this ratio. Both molecular oxygen and carbon monoxide are carried by RBCs and are therefore similarly affected by a change in hematocrit.

Quantitative measurement of cerebral metabolic rate of glucose by means of dual-head coincidence gamma camera and 2-deoxy-2- [18F] fluoro-D-glucose

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S670-S670
Author(s):  
Katsufumi Kajimoto ◽  
Naohiko Oku ◽  
Yasuyuki Kimura ◽  
Makiko Tanaka ◽  
Hiroki Kato ◽  
...  
Keyword(s):  
Metabolic Rate ◽  
Gamma Camera ◽  
Quantitative Measurement ◽  
Cerebral Metabolic Rate

On the Regulation of the Respiration in Reptiles

1961 ◽  
Vol 38 (2) ◽  
pp. 301-314 ◽  
Author(s):  
BODIL NIELSEN
Keyword(s):  
Steady State ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Temperature Interval ◽  
Normal Values ◽  
Pulmonary Ventilation ◽  
The Body ◽  
Respiratory Frequency ◽  
Temperature Changes ◽  
Instantaneous Increase

1. In two species of Lacerta (L. viridis and L. sicula) the effects on respiration of body temperature (changes in metabolic rate) and of CO2 added to the inspired air were studied. 2. Pulmonary ventilation increases when body temperature increases. The increase is brought about by an increase in respiratory frequency. No relationship is found between respiratory depth and temperature. 3. The rise in ventilation is provoked by the needs of metabolism and is not established for temperature regulating purposes (in the temperature interval 10°-35°C). 4. The ventilation per litre O2 consumed has a high numerical value (about 75, compared to about 20 in man). It varies with the body temperature and demonstrates that the inspired air is better utilized at the higher temperatures. 5. Pulmonary ventilation increases with increasing CO2 percentages in the inspired air between o and 3%. At further increases in the CO2 percentage (3-13.5%) it decreases again. 6. At each CO2 percentage the pulmonary ventilation reaches a steady state after some time (10-60 min.) and is then unchanged over prolonged periods (1 hr.). 7. The respiratory frequency in the steady state decreases with increasing CO2 percentages. The respiratory depth in the steady state increases with increasing CO2 percentages. This effect of CO2 breathing is not influenced by a change in body temperature from 20° to 30°C. 8. Respiration is periodically inhibited by CO2 percentages above 4%. This inhibition, causing a Cheyne-Stokes-like respiration, ceases after a certain time, proportional to the CO2 percentage (1 hr. at 8-13% CO2), and respiration becomes regular (steady state). Shift to room air breathing causes an instantaneous increase in frequency to well above the normal value followed by a gradual decrease to normal values. 9. The nature of the CO2 effect on respiratory frequency and respiratory depth is discussed, considering both chemoreceptor and humoral mechanisms.

The oxidation of Carbon with Atomic Oxygen

1959 ◽  
Vol 12 (2) ◽  
pp. 114 ◽  
Author(s):  
JD Blackwood ◽  
FK McTaggart
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Radio Frequency ◽  
Molecular Oxygen ◽  
Atomic Oxygen ◽  
Graphitic Carbon ◽  
Carbon Surface ◽  
Direct Oxidation ◽  
Radio Frequency Field ◽  
Frequency Field

Atomic oxygen, produced by dissociation of molecular oxygen in a radio frequency field, will react with amorphous or graphitic carbon at room temperatures and both carbon monoxide and carbon dioxide appear in the product gases. Carbon monoxide appears to be the primary product of oxidation of carbon, the carbon dioxide being produced by direct combination of carbon monoxide with oxygen which takes place mainly at the carbon surface. Atomic oxygen will also react with carbon dioxide to produce carbon monoxide and molecular oxygen but the quantity of carbon monoxide produced by this reaction is small compared to that produced by direct oxidation of the carbon.

New Steady-State Technique for Measuring Shale Core Plug Permeability

2014 ◽  
Author(s):  
Mehrdad Zamirian ◽  
Kashy Kashy Aminian ◽  
Samuel Ameri ◽  
Ebrahim Fathi
Keyword(s):  
Steady State ◽  
State Technique

scholarly journals Using the rPatlak plot and dynamic FDG-PET to generate parametric images of relative local cerebral metabolic rate of glucose

2012 ◽  
Vol 57 (28-29) ◽  
pp. 3811-3818 ◽  
Author(s):  
YiGen Wu ◽  
Yun Zhou ◽  
ShangLian Bao ◽  
SungCheng Huang ◽  
XiaoHu Zhao ◽  
...  
Keyword(s):  
Metabolic Rate ◽  
Fdg Pet ◽  
Parametric Images ◽  
Cerebral Metabolic Rate
Sign in / Sign up

Export Citation Format

Share Document