Showing papers in "Respiration Physiology in 1983"

TL;DR: The findings indicate that, even though the three types of receptors differ in sensory modality, they concur in exhibiting a predominant activity during inspiration, in fact, 65% of all receptors are active during eupneic inspiration and their activity increases markedly during upper airway obstruction.

TL;DR: It is demonstrated that there is both experimental and theoretical justification for the use of both exponents in describing the variation of basal energy metabolism among animals of different size and species.

TL;DR: The large breathing oscillations and periodic apnea correlated well with the ventilatory sensitivity to hypoxia (r = 0.85), supporting the hypothesis that a high gain of the peripheral chemoreflex is conductive to periodic breathing.

TL;DR: Changes in Pmax underestimated changes in force during growth, since both SA and Pmax increased with age, and the derived forces, as compared with pressures, proportionally increased more with age.

TL;DR: It is concluded that in most normal individuals standing at rest, the end-expiratory position is at least in part actively determined and such an abdominal muscle use, although causing quiet breathing to depart from the relaxed abdominothoracic configuration, may be associated with minimum respiratory work.

TL;DR: It is hypothesize that in the long term, increased oxidative enzyme activities allow increased maximum flux capacity of aerobic metabolism, which in turn calls for physiological adjustments in O2 transfer systems; flux limits of the former must be matched by flux Limits of the latter.

TL;DR: The evidence for the presence of oxygen stores in the lungs, blood and systemic musculature of diving mammals, the modifications in the respiratory functions of blood that may be important in utilizing the lung and blood oxygen stores, and the potential importance of the oxygen stores and the respiratory function of blood in supporting short-duration, aerobic dives are examined.

TL;DR: The observed elevation in ammonia excretion was probably the result of an exercise-induced increase in nitrogen metabolism rather than of production of ammonia for the purpose of acid-base regulation.

TL;DR: It is suggested that increasing tidal volume may directly distort the alveolar type II cell; each cell reacts to its own threshold distortion by releasing a pool of S in all-or-none fashion.

TL;DR: The neural respiratory response to systemically administered theophylline is mediated at the level of the brainstem, and somehow involves the action of the neurochemical dopamine.

TL;DR: In spite of arterial hypoxia at the end of incubation and some loss of blood during hatching, blood O2 transport was not seriously impaired during pipping and hatching as revealed by 'venous' blood gases.

TL;DR: Changes in the metabolism of both central 5HT and CB DA may be related to the mechanisms mediating ventilatory acclimatization to chronic hypoxia.

TL;DR: The results suggest that small airways obstruction does not occur after a marathon, and the significant increase in alveolar-capillary membrane resistance may reflect the occurrence of subclinical edema.

TL;DR: The apparent resistance to fatigue shown by the inspiratory muscles may be due to many factors including the central organization of their motoneurones and to local neuromuscular properties.

TL;DR: It is concluded that the considerable increase in extracellular Mg2+ and Ca2+ cannot be the result of release from muscle cells and has to be attributed to release from skeleton and shell.

TL;DR: Upper airway negative pressure acts centrally on both inspiratory and expiratory timing as well as on the motor output of thoracic and upper airway respiratory muscles, suggesting that upper airways respiratory muscles primarily mediate this response.

TL;DR: Data obtained on the American Medical Research Expedition to Everest were used to analyze the oxygen transport system during maximal exercise at the highest point on earth and showed it is possible to account for a VO2 max of over 1 L/min while keeping the PO2 of mixed venous blood above 15 Torr.

TL;DR: The mathematical description of the CO2 curve was employed to quantitate the in vivo Haldane factor (fH) from simultaneous arterial and mixed venous blood samples in 20 healthy exercising subjects and in 20 patients with severe obstructive lung disease.

TL;DR: In 6 subjects measurements were repeated before and after upper airway lignocaine anaesthesia, which abolished the differences in respiratory timing and drive between the breathing routes, and it is suggested that there may be upperAirway flow receptors which influence respiratory timing.

TL;DR: It is concluded that the discordant scaling of D LO2 and VO2max with respect to body mass is not an artifact of the model for calculating DLO2 from morphometric data.

TL;DR: The present data strongly suggest that the bronchomotor response to cold air breathing is a reflex, mediated by afferent fibres in the superior laryngeal nerves and in the vagus nerves.

TL;DR: Differences of recruitment order during inspiration are related for phrenic motoneurones, partly to differences of excitability but mainly to a dual central respiratory drive which is assumed to divide the population into two components.

TL;DR: Assessment of the effects of severe, short-term exercise stress on the acid-base balance, the O2 transporting properties and the cofactors for O2 binding in the blood of Tinca tinca found a drastic decrease in arterial blood pH which is attributed to a mixed respiratory and metabolic acidosis.

TL;DR: Changes suggest that the greater susceptibility to chronic HA exposure observed in the H rats is related to a more severe right ventricular overloading and perhaps failure, secondary to a a more extreme pulmonary hypertension.

TL;DR: It is concluded from the recalculated CO2 Bohr factor and from the temperature effect on the buffer value that carp hemoglobin forms carbamate which decreases at a higher temperature, which can partly account for the increase in whole blood oxygen affinity in carp acclimated at a high temperature.

TL;DR: The results suggest that mechanisms responsible for augmented breaths act similarly on upper airway muscles and the diaphragm.

TL;DR: It is concluded that: (1) there is no interaction in the ventilatory response between peripheral O2-CO2 and central CO2 stimuli; and (2) a positive interaction inThe ventilations between peripheral hypoxia and CO2 originates from the arterial chemoreceptors.

TL;DR: It is found that Ecf pH changes caused by changes in PaCO2 give rise to greater ventilatory responses than the same ecf pHChanges caused by (isocapnic) changes in pHa, and within the pH ranges measured, isOCapnic pHecf-ventilatory response lines at higher PaCO 2 are shifted upwards compared with those at lower PaCO3 levels.

TL;DR: Morphometric estimates of diffusion capacity have traditionally been calculated for oxygen while physiologic techniques have been used to determine diffusion capacity for carbon monoxide, and results suggest that the same lung function is not being accurately measured by at least one of these two techniques.

TL;DR: The results confirm the growth accelerative effect of oxygen and suggest that the degree of growth enhancement is proportional to the ambient oxygen concentration.