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Agostoni E - - 1977
In anesthetized subjects rib cage strapping (RCS) did not change tidal volume (VT) and increased ventilation (V), whereas abdomen strapping (AS) markedly decreased VT and V. Both kinds of strapping decreased expiratory duration (TE), but did not change inspiratory duration (TI) and breathing rate. RCS and AS decreased lung volume ...
Ward S A - - 1977
Four healthy young men and women, selected for the responsiveness and steadiness of their breathing, were studied in rest and mild exercise (58 runs) while receiving alternate inspirates of low and high PCO2 (0 and 8.6 kPa). PACO2 oscillated between ca. 6 and 7.5 kPa (45-55 torr); PACO2 was held ...
Cunningham D J - - 1977
1. Three healthy young males were maintained for sessions of about 1 hr in a state of mild asphyxia (PA,O2 approximately 55, PA,CO2 approximately 45 torr), i.e. with moderately strong drives from both arterial and intracranial chemoreceptors. Tidal volume (VT), breath duration (TT) and duration of inspiration (TI) were recorded, ...
Stemler F W - - 1977
Men ran to a voluntary end point under the following conditions listed in increasing order to resistance, expressed as inspiratory/expiratory in mmH2O at a flow of 4 l-s-1: 1) bare-headed 0/0; 2) face mask 0/0; 3) face mask -6/14; 4) mouthpiece and valves -25/29; 5) face mask -96/62; and 6) ...
Mauderly J L - - 1977
Nitrogen washout curves resulting from open circuit N2 washouts of unsedated human and canine subjects were constructed by plotting the breath-by-breath end-expiratory N2 fraction (Fn2) against breath number on a semilog scale. Curves were analyzed graphically, and the slope of the 2nd of the 3 components was expressed by B ...
Knox C K - - 1976
The lung stretch reflex characteristics of unanesthetized decerebrate cats were determined using servo-controlled lung volume changes before and after bilateral lesion of the dorsolateral rostral pons in the region of nucleus parabrachialis medialis (NPBM). During the inspiratory phase the time-dependent threshold curve for inspiratory inhibition by lung inflation was shifted ...
Miserocchi G - - 1976
In anesthetized tracheotomized cats we compared the time sequence of ventilatory events with neurological events (electrical activity of the diaphragm) during the breathing cycle. We found that under control conditions a phase shift existed between the neurological and the spirometric duration of inspiration, amounting to about 150 ms. This phase ...
Winning A J - - 1976
Tidal volume (VT), and inspiratory (tI) AND EXPIRATORY (TE) durations have been measured in anaesthetized cats on stimulation of alveolar type J (nociceptive) and lung irritant receptors by intravenous injections of phenyl diguanide and of histamine acid phosphate respectively. The reflexes were studied during eupnoea, hypercapnic and hypoxic hyperpnoea, during ...
Agostoni E - - 1976
In anesthetized dogs and rabbits passive or active limb movements (1) shifted to the left the relationship between tidal volume (Vt) and inspiratory time (Ti), (2) lowered the relationship between expiratory time (Te) and Ti and decreased its slope, and (3) increased the output to the inspiratory muscles (Vt/Ti). These ...
Phillipson E A - - 1976
We have investigated immediate and progressive ventilatory responses to external elastic loads in five dogs with cervical vagal loops. Three dogs were studied while awake (W) and during non-REM sleep (S); the other two during barbiturate anesthesia (A). Elastic loads were applied at the end expiration for 1-6 breaths by ...
Schaanning J - - 1976
Thirty-four patients with chronic obstructive lung disease were exercised stepwise up to maximal work load. V02 at maximal work load showed a slightly significant correlation to FEV1, while a closer association with VC as well as Ve and Vt was noted. In most patients Vt during maximal exercise was around ...
Goldstein I - - 1975
Increases in functional residual capacity (FRC) decrease inspiratory muscle efficiency; the present experiments were designed to determine the effect of FRC change on the ventilatory response to exercise. Six well-trained adults were exposed to expiratory threshold loads (ETL) ranging from 5 to 40 cmH2O during steady-state exercise on a bicycle ...
Kay J D - - 1975
1. The breathing pattern, that is the changes in tidal volume (VT), and in inspiratory (TI) and expiratory (TE) durations, has been studied as ventilation increases in exercise. 2. Five healthy subjects were studied in steady-state exercise on a bicycle ergometer, breathing air, at two speeds of pedalling and at ...
Kay J D - - 1975
1. The breathing pattern, that is the relation between tidal volume (VT) and the inspiratory (TI) and expiratory (TE) durations, has been studied for individual breaths (forty in each steady state). 2. Five healthy subjects were studied in steady-state exercise on a bicycle ergometer breathing air; three of them were ...
Zuskin E - - 1975
Changes in respiratory function during a 10-year period were studied in a group of 34 men and 19 women exposed to coarse cotton dust. The prevalence of byssinosis increased significantly in the 10-year period both in men and women; in addition, there was an increase in the prevalence of all ...
Phillipson E A - - 1975
We have investigated the possibility that afferent vagal stimuli may be responsible for the excessive ventilatory drive during exercise characteristic of many diffuse pulmonary parenchymal diseases. Studies were performed on four conscious dogs with cervical vagal loops, in whom experimental pneumonitis was induced by the intravenous administration of complete Freund's ...
Rebuck A S - - 1975
Ventilatory responses to hypoxia, with and without an inspiratory resistive load, were measured in eight normal subjects, using a rebreathing technique. During the studies, the end-tidal P-CO2 was kept constant at mixed venous level (Pv-CO2) by drawing expired gas through a variable CO2-absorbing bypass. The initial bag O2 concentration was ...
Gautier H - - 1975
Ventilation was monitored in awake and anesthetized cats breathing air or CO2 mixtures, both before and after lesions in the pneumotaxic center region and after subsequent bilateral vagotomy. Cats with pontile lesions had, relative to intact state, a prolonged inspiratory duration and an increase in tidal volume and expiration duration. ...
Bartoli A - - 1973
1. Breuer's hypothesis that the vagus nerves exert a tonic control of respiratory rhythm, in addition to the phasic control, was examined.2. Closed-chest cardiopulmonary bypass was instituted in dogs weighing 20-30 kg anaesthetized with chloralose. Respiratory rhythm was recorded from a phrenic electroneurogram.3. Complete muscular paralysis induced with gallamine triethiodide ...
Eldridge F L - - 1972
1. The respiratory response, measured directly as tidal volume or indirectly by using integrated peak phrenic activity, to brief intermittent chemical stimulation or depression of the carotid body was determined in anaesthetized cats. Recordings of carotid sinus nerve impulses allowed precise timing of the stimulus.2. Stimulation of the carotid body ...
Clark F J - - 1972
1. The relationships between the depth of a breath and the durations of the inspiratory and expiratory phases have been studied in cat and in man during rebreathing, and in cat using artificial inflations of different magnitudes and timings.2. In the cat, the apparent volume threshold for termination of inspiration ...
Potter W A - - 1971
The interrelationships among transpulmonary pressure, flow, and volume during exhausting exercise were studied in 12 males with chronic obstructive lung disease. Expiratory pressure during exercise was compared with flow-limiting pressure (P(max)) measured at rest. In 11 patients, expiratory pressure during exercise exceeded P(max), indicating that ventilation became mechanically inefficient. P(max) ...
Bouhuys A - - 1966
The auditory signal provided by a soprano recorder in a breathing circuit can help human subjects to regulate inspiratory and expiratory airflow rates at constant preset levels. This method of airflow control is useful in studies of the static and dynanic mechanical properties of the lungs and may have additional ...
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