Showing papers in "Respiration Physiology in 1971"

TL;DR: A model and method for estimating pulmonary diffusion capacity from morphometric information gathered on fixed lung specimens is presented and the introduction of appropriate physical coefficients permits calculation of morphometric values of pulmonary and membrane diffusion capacities which can be used in attempts of quantitative structure-function correlation.

TL;DR: The transfer rate of a gas species, with dimension (quantity of substance)·(time)−1, may thereby be clearly distinguished from the volume flow rate, which has the dimension (volume).

TL;DR: Preliminary allometric equations relating avian respiratory variables to body weight permit a series of tentative statements regarding avian respiration which were hitherto impossible.

TL;DR: The data suggest that under conditions of hypoxia two different receptor systems in the carotid body may be stimulated or the same system in two different ways; that the Hypoxia-produced transmitter in the vehicle body is not essentially dependent on an increased (H + a ).

TL;DR: Evidence is provided that O 2 tension of ambient air influences postnatal growth of the lung during the growth period investigated, and lung volumes were increased under hypoxic conditions and under hyperoxia.

TL;DR: It is indicated that the spontaneous sigh is a complex response to lung inflation, brought about by a vagally mediated mechanoreflex, which requires and is regulated by afferent information from peripheral chemoreceptors.

TL;DR: When the carbonic anhydrase of the carotid body, but not of the perfusing blood was inhibited, the response to hypercapnia was slower, did not overshoot, and slowly came to the same steady level which it had reached in the steady state of its response before carbonicAnhydrase was inhibited.

TL;DR: It is found that the observed relations that V O 2 is proportional to W 0.73 , and respiratory frequency, f, is proportionalto W −0.27 make the phase relations between certain parameters that vary with respiration independent of body size.

TL;DR: Blood pH and PCO2 values indicate that the North American ganoid fish relies strictly on ventilation of the gills for O2 and CO2 exchange at low temperatures, and as the temperature increases, the lung becomes the predominant organ for oxygen extraction, the bloodPCO2-increases, plasma bicarbonate does not rise and the plasma pH falls.

TL;DR: Results indicate that in the turtle, Pseudemys, at least, the pH-temperature regulation is achieved by respiratory adjustment of Paco2, and the pattern of breathing observed in the turtles is consistent with the previous report on the relationship between blood pH and body temperature in various poikilothermic vertebrates.

TL;DR: Preliminary results suggest that an increased colloid osmotic effect of the albumen plays a role in loss of water by the membranes of fertilized eggs.

TL;DR: The highlander avoided the high levels of ventilatory work and exertional dyspnea experienced by the sojourner without compromising systemic O2 delivery when exposed to moderate hypoxia, and maintained PaCO2 at or above resting levels.

TL;DR: The results indicate that the ability to increase ventilation rate above the resting value, is less than that in terrestrial mammals, and blood oxygen tensions may play a primary role in influencing the length of the dive.

TL;DR: The findings indicate that young rats exposed to high altitude undergo an initial period of mild pulmonary edema; during this period the rate of alveolar development is probably not increased above normal, but with continued exposure, the edema subsides andAlveolar proliferation occurs at a faster rate than in control animals.

TL;DR: The average oxygen consumption of Japanese Waltzing Mice exceeds that of normal white laboratory mice by 80 percent and the alveolar and capillary surface area and the capillary volume are some 60 percent larger than those of NM.

TL;DR: It appears that such embryos near hatching encounter physiologically critical limits concerning blood gas metabolism, and a few embryos died even after reaching the air by pipping.

TL;DR: The direction of gas flow recorded in the dorsobronchus during spontaneous breathing and during artificial ventilation was from the mesobronchu to the parabronchi both in inspiration and expiration, in accordance with the unidirectional flow hypothesis.

TL;DR: The development of apneustic breathing following vagotomy in the animals with chronic lesions in the pontile pneumotaxic areas constitutes impressive support for the physiological participation of the pneumotAXic neurons in the neurogenesis and regulation of respiratory rhythmicity.

TL;DR: Findings further corroborate the view that the alveolar surface is lined by extracellular material topped by a smooth surface film probably related to surfactant.

TL;DR: CO2 analysis indicates that air enters the anterior sacs, partially at least, by the tertiary bronchi and enters the posterior sacs via the direct non-exchanging connections.

TL;DR: It is concluded that morphometrieally estimated D l must always be higher than physiological estimates because it supposes full availability of the lung for O2 transfer.

TL;DR: It is suggested that the embryo encounters respiratory alkalosis with metabolic acidosis in the middle stage of development, and then the acid-base status approaches normal level with time.

TL;DR: Under all conditions, PVO 2 was lower than in most other mammals, but always exceeded 20 mm Hg, reflecting the efficient mechanisms of O 2 extraction in the llama.

TL;DR: The considerably lower values obtained in intact muscles are attributable to exchange of H + of HCO − 3 across the muscle cell membrane accompanying changes in P co2.

TL;DR: Unmyelinated axons in a Schwann cell sheath have been found in the rat lung, in alveolar wall deep within the acinus: they are rare and may be sensory, their position suggesting an association with the J receptor.

TL;DR: The observations support the Bethe-Hazelhoff theory according to which the gas flow through the parenchymal parabronchi is unidirectional from caudal to cephalad during inspiration as well as during expiration.

TL;DR: The conclusion drawn from the analysis is that the computed time course of diffusive mixing in a given lung model, and its effects on the concentration gradients in the alveolar gas, are crucially dependent upon the boundary conditions employed.

TL;DR: These findings support Scholander's hypothesis that some marine mammals are protected from decompression sickness by cartilaginous reinforcement of the small airways which permits alveolar emptying during a dive, so isolating compressed gas from pulmonary capillary blood.

TL;DR: The effectiveness of a decrease in oxygen affinity as an adaptive mechanism and the causes for the increase in 2,3 DPG at high altitude are discussed.

TL;DR: A mathematical treatment was developed which is applicable to the transfer of any gas in non-homogeneous lungs and provides an explanation for the well-known discrepancy between morphometric and functional D estimates, as well as for the fact that DCO values higher than DO2 values are encountered in the literature.