Biomaterial Database

Intra versus interregional nitrogen gradients in the single breath nitrogen test. 1980

M Laviolette, and Y Cormier

To investigate the genesis of cardiogenic oscillations (C.O.) and the slopes of the single-breath nitrogen test, we studied ten healthy volunteers with a modified test. This test utilized incremental volumes of air from 10% to 100% vital capacity (VC) after a nitrogen washout with oxygen. Subjects exhaled to residual volume, inspired the air volume and completed a full inspiration with oxygen. C.O. and both slopes were positive with low air volumes and negative with a VC of air. The slope of phase IV showed a linear decrease with the increasing inspired air volume, and reached zero with an air volume of 38% VC. AT higher volumes it became progressively more negative. The slope of phase III and C.O. were highly positive with 10% to 50% VC air volume then subsequently decreased. The values for C.O. and the slope of phase III were significantly different (P < 0.001) from those of the slop of phase IV and the apex-base gradients predicted by the model of Milic-Emili et al. These results suggest that intraregional gradients are significantly involved in the genesis of C.O. and the slop of phase III.

UI	MeSH Term	Description	Entries
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008176	Lung Volume Measurements	Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.	Lung Capacities,Lung Volumes,Capacity, Lung,Lung Capacity,Lung Volume,Lung Volume Measurement,Measurement, Lung Volume,Volume, Lung
D008297	Male		Males
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009584	Nitrogen	An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
D003011	Closing Volume	The lung volume at which the dependent lung zones cease to ventilate presumably as a result of airway closure.	Closing Volumes,Volume, Closing,Volumes, Closing
D005260	Female		Females
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults