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Yasukouchi A - - 1990
Five subjects were tested to determine the threshold for detection of an added resistance to inspiration in three tests, one at rest and two with exercise (mild = 50 W; moderate = 100 W) on a cycle ergometer. Changes in the breathing pattern were examined at added resistances near the ...
Estenne M - - 1990
STUDY OBJECTIVE: To determine the role of the clavicular portion of the pectoralis major during cough in tetraplegic subjects. PATIENTS: Eight patients with longstanding traumatic transection of the lower cervical cord. METHODS: The electromyographic activity of the pectoralis major and abdominal external oblique muscles and the changes in the anteroposterior ...
Grucza R - - 1990
Kinetics of cardiorespiratory response to dynamic (DE) and then to rhythmic-static exercise (RSE) was compared in nine male subjects exercising in an upright position on a cycle ergometer at an intensity of about 50% VO2max and a mean pedalling frequency of 60 rpm over 5 min. Respiratory frequency (fR), tidal ...
King M - - 1990
We have reported previously that high-frequency oscillation of the chest wall (HFO/CW) enhances the tracheal mucus clearance rate (TMCR) in dogs. This enhancement of TMCR may be due in part to the expiratory bias in peak flow rate (VE/VI greater than 1) that occurs during HFO/CW. We examined this factor ...
Borison H L - - 1989
T-2 toxin, a trichothecene mycotoxin, was injected iv or ip in the single lethal dose of 2 mg/kg. Vomiting was elicited in normal and decerebrate cats with an average onset time of 26.6 min. Chronic ablation of the area postrema significantly delayed the emetic latency to 304 min. Polygraph recording ...
Ainsworth D M - - 1989
Using 6 chronically instrumented awake dogs, we contrasted the ventilatory and respiratory muscle EMG responses to steady-state normoxic hypercapnia with those occurring at similar levels of ventilation during steady-state treadmill exercise. During hypercapnia, increases in ventilatory output were primarily due to increments in VT whereas during exercise, increases in minute ...
Baer R - - 1989
Breathing pattern and static lung volumes were studied in 10 subjects at rest and during incremental-load cycle ergometry under three different conditions, viz. with normal pressure in the airways (control) and during continuous positive- and negative-pressure breathing (CPPB, CNPB) of +15 and -15 cmH2O. End-expiratory, end-inspiratory and mid-expiratory volumes were ...
Smith J - - 1989
The coordination of breathing and swallowing was studied in seven normal males at rest, as well as during eating and drinking. Ventilation was monitored using respiratory inductive plethysmography and swallowing was recorded by submental electromyogram. Swallowing occurred almost exclusively in expiration. Two hundred and seventy-one swallows were seen and only ...
Goldstein R - - 1989
We evaluated application of a Pth device for testing inspiratory muscle endurance among patients with severe but stable COPD. Endurance time in five patients was reproducible. Magnitude of variability was +/- 1.26 minutes with a range of +/- 0.19 to +/- 2.28 minutes. Eleven inpatients completed inspiratory muscle training twice ...
Baydur A - - 1989
To evaluate the effects of abnormal respiratory mechanics and neuromuscular drive on the various components of elastic load compensation, we studied 16 anesthetized patients with kyphoscoliosis whose mean passive and active respiratory elastance (Ers and E'rs, respectively), active respiratory resistance, and peak inspiratory occlusion pressure were, respectively, 89, 84, 100, ...
Harber P - - 1989
The degree to which subjective tolerance of respirator loads is related to physiologic effects and to psychophysical load sensitivity was investigated in this study. Fifty-two normal volunteers walked on a treadmill while breathing through a variety of respirator-type resistance and dead-space loads. Visual analog scales measuring perceived time limit of ...
Freitag L - - 1989
The present study evaluated whether high-frequency oscillations (HFO) with biased flow profiles applied at the airway opening are capable of altering mucus clearance. In eight anesthetized sheep, artificial mucus (100 P) was infused continuously (1 ml/min) into the left main bronchus via a cannula inserted through the dorsal wall of ...
Hodous T K - - 1989
A useful system to study the cardiopulmonary effects of respirators in the workplace would be reliable, portable, and lightweight and would not encumber the nose or mouth or require modification to the respirator. Twenty men using such a system (which measured ventilatory parameters by respiratory inductive plethysmography [RIP]) were studied. ...
Kinnear W - - 1989
We have studied the contribution of vagal pulmonary receptors to the stability of breathing during postural changes in humans. Quiet breathing was quantified in the seated and the supine postures in 10 patients with chronic pulmonary denervation due to heart-lung transplantation and 10 age and sex matched normal controls. In ...
Poon C S - - 1989
Eight healthy young men underwent two separate steady-state incremental exercise runs within the aerobic range on a treadmill with alternating periods of breathing with no load (NL) and with an inspiratory resistive load (IRL) of approximately 12 cmH2O.1-1.s. End-tidal PCO2 was maintained constant throughout each run at the eucapnic or ...
Gardner W N - - 1989
We compared respiratory patterning at rest and during steady cycle exercise at work rates of 30, 60, and 90 W in 7 male chronically laryngectomized subjects and 13 normal controls. Breathing was measured with a pneumotachograph and end-tidal PCO2 by mass spectrometer. Inspired air was humidified and enriched to 35% ...
Phillips M S - - 1989
Twenty eight subjects (mean age 64 years) who had been treated for tuberculosis by thoracoplasty in the past performed an increasing work rate exercise test, from which maximum oxygen consumption (VO2max), ventilation and heart rate were measured. VO2max was significantly lower than predicted, being 0.75 l/min in 17 subjects, 1.0 ...
Badier M - - 1989
In anesthetized rabbits, direct and integrated phrenic neurogram (Ephr) and electromyograms from the diaphragm (Edi) and intercostal (Eic) (2nd space) and transversus abdominis muscles (Etr) were simultaneously recorded in two protocols. 1) In animals breathing spontaneously, we used infinite inspiratory (RI) or expiratory (RE) resistive load and intravenous injections of ...
Flynn M G - - 1989
The effects of six weeks of threshold pressure inspiratory muscle training (IMT) on inspiratory muscle performance, breathing pattern and exercise performance were studied in eight patients with severe airflow obstruction. The results indicated that IMT improved inspiratory muscle performance but did not affect exercise performance or breathing pattern during maximal ...
Costa M M - - 1989
The effect of using specialized or no specialized muscle groups on ventilatory threshold (VT) and on maintenance of steady-state oxygen consumption during long term exercise on treadmill and on cycle ergometer was studied in ten endurance runners and nine cyclists. Initially, maximum oxygen consumption (VO2max) and VT were determined. Oxygen ...
Iscoe S - - 1989
The role of phrenic afferents in controlling inspiratory duration (TI) at elevated end-expiratory lung volume (EEV) has been studied in pentobarbital-anesthetized, spontaneously breathing cats with intact vagi. Responses to increases in EEV, induced by imposition of an expiratory threshold load (ETL) of 10 cmH2O, were monitored before and after section ...
Wilson J R - - 1989
Current regulations governing the certification of respiratory protective devices are based on data published in the early 1950s. The limited data base of this early work and documented increases in the average height of the population underscore the need for additional information concerning the parameters of certification. In the present ...
Ramonatxo M - - 1989
The aim of this study was to specify whether during exercise the neural response to increased resistive load in asthmatic children corresponds to a modification of the neuromuscular inspiratory drive, to a modification of the breathing pattern, or to both. Thus, nine children with mild or moderate asthma (aged 10-15 ...
Boule M - - 1989
Breathing pattern during exercise on a cycle ergometer was studied in 18 untrained children aged from 6 to 15 years of age (9 boys, 9 girls). Oxygen uptake, tidal volume, minute ventilation, all normalized for body weight (VO2BW, VT BW, VE BW), respiratory frequency (f), inspiratory (TI) and expiratory (TE) ...
Harver A - - 1989
We determined the influence of the background level of mechanical impedance on the respiratory responses to very small mechanical loads, at or below the threshold for conscious perception. We used a pseudorandom load application technique to estimate the immediate pattern responses from the zeroth lag of the cross correlation between ...
Vertes C - - 1989
Aminophylline or VIP (Vasoactive Intestinal Peptide) given ip. or iv. have marked bronchodilatory effects. The onion extracts protect guinea pigs as well as human patients against allergen-induced bronchial spasms (Dorsch et al.). Recently it has been shown that lipophilic components of onions seem to be responsible for the antiasthmatic effects. ...
Violante B - - 1989
We investigated the effects of intravenously administered aminophylline (A; 6 mg/kg over 20 min, followed by 0.9 mg/kg/h), salbutamol (S; 4 micrograms/kg over 20 min, followed by 3 micrograms/kg/h) and placebo (P; saline solution) on the strength of the respiratory muscles, the ventilatory endurance and the exercise tolerance in 7 ...
Harber P - - 1989
The effects of respiratorlike inspiratory resistance (IR), expiratory resistance (ER), and dead space (DS) were assessed in a group of 11 normal volunteers during moderate steady-state (SS) and rapidly incremented (RI) exercise. The physiologic effects of IR were predominant, increasing inspiratory time, duty cycle, and several measures of ventilatory work. ...
Bunc V - - 1989
In order to evaluate changes in parameters at the ventilatory threshold (VT) and in mechanical efficiency (ME) during training in the years 1982 and 1983 we tested seven top-class endurance runners on a treadmill. The VT and ME were assessed during their training period (January 1982 and 1983) and during ...
Hecker B R - - 1989
Lower intercostal and abdominal muscles interact with other respiratory muscles to produce inspiration as well as expiration. Intercostal nerve blockade from T6-T12 was produced in seven healthy males to study its effect on: 1) supine pulmonary function, 2) inspiratory effort, 3) hypercapnic ventilatory response, including mouth occlusion pressures with and ...
Olgiati R - - 1989
We assessed the effects of respiratory muscle training (RMT) in patients with multiple sclerosis (MS) on vital capacity (VC), maximal static inspiratory (PImax) and expiratory (PEmax) pressures and maximal voluntary ventilation (MVV). Eight patients (mean age 53, range 42 to 65 years) with stable disease and respiratory muscle weakness (RMW; ...
Damato S - - 1989
Changing the depth and the frequency of breathing affects the efficiency of ventilation. This has been studied in eight normal subjects using the technique of nitrogen washout whilst breathing a mixture of 79% argon and oxygen. The signals were converted to digital data at 50 Hz and all calculations were ...
Concu A - - 1989
To investigate the relative contributions of the central and peripheral neural drive to hyperventilation at the onset of muscular exercise, five volunteers were tested during the first ten breaths while performing both voluntary (VM) and passive (PM) ankle rotations with a frequency of 1 Hz and through an angle of ...
Klas J V - - 1989
We determined the efficiency with which maximal exercise ventilatory output could be mimicked voluntarily. Five normal subjects exercised to maximal volitional effort and flow:volume and pressure:volume loops, and end-expiratory lung volume (EELV) and breathing pattern were measured. All subjects increased expiratory flow rate and reduced EELV sufficiently so that the ...
Art T - - 1989
This paper attempts to evaluate the changes in the mechanical work of breathing induced by the increase of ventilation in ponies exercising on a treadmill. Airflow, tidal volume (VT) and oesophageal pressure were simultaneously recorded in eight ponies (four to six years old and weighing 258 +/- 11 kg) before, ...
Polianski J M - - 1989
To evaluate the consequences of breathing pattern variations inherent to lung disease on the rebreathing measurement of lung tissue volume (Vt), we carried out a study of ten normal human subjects in whom we assessed the effects of changes in rebreathing volume (Vreb), additional deadspace volume (AVD), respiratory rate (RR), ...
Sackner M A - - 1989
We describe a single-posture method for deriving the proportionality constant (K) between rib cage (RC) and abdominal (AB) amplifiers of the respiratory inductive plethysmograph (RIP). Qualitative diagnostic calibration (QDC) is based on equations of the isovolume maneuver calibration (ISOCAL) and is carried out during a 5-min period of natural breathing ...
Goodman L S - - 1988
The purpose of this study was to determine the relationship between previously prescribed training heart rates (THR) for patients training for six months or more in a cardiac rehabilitation program (CRP), calculated Karvonen percentage heart rate reserve (THRk), and the ventilatory threshold (VT). In twenty male patients (ages 41-63) with ...
Takano N - - 1988
Fourteen subjects performed cycle exercise at work loads of 0 and 1 kp, each for 3 min, during which the pedal rate was kept constant by various external cues. Six cues were used in order: no cue (N1), a speedometer dial (S), a flashing light (F), a verbal command (V), ...
Coates A L - - 1988
Although exertional hypercapnea has been observed in patients with advanced cystic fibrosis (CF), the causes have not been fully elucidated. In 14 patients aged 15 to 35 yr of age with advanced CF, the effects of chronic airflow limitation (CAL), increased physiologic dead space (VD), and the timing components of ...
O'Donnell D E - - 1988
To cope with the increased ventilatory demands of exercise, patients with severe expiratory flow limitation adopt strategies that ultimately place greater demands on their inspiratory muscles. Increased inspiratory muscle work may contribute to dyspnea causation and exercise limitation in such patients even before their ventilatory ceiling is attained. In this ...
Jayaweera A R - - 1988
The objective of this study was to elucidate the resistive, elastic, and total inspiratory muscle work and mainly the efficiency of the inspiratory muscle work in still standing and in exercising dogs. In 180 experiments with nine mongrel dogs, respiratory and circulatory functions were recorded at rest and during a ...
Vai F - - 1988
The correlation between heart rate (HR) and three respiratory parameters, minute ventilation (VE), tidal volume (Vt), and respiratory rate (RR), were studied. Four healthy subjects performed four exercise tests (duration 30 seconds at 50, 100, 150, or 200 W), in random order. Cardio-respiratory parameters were recorded respiratory cycle by respiratory ...
Criner G J - - 1988
We have proposed that unsupported arm exercise alters ventilatory muscle recruitment and precipitates dyspnea in patients with severe chronic airflow obstruction (CAO). To test this hypothesis, we studied 11 patients with CAO during symptom-limited, unsupported arm exercise (UAE) and compared it with supported arm cycling (SAE). During each exercise period, ...
Ellingsen I - - 1988
Conflicting opinions exist concerning the breathing pattern in man during resting and stimulated ventilation. Some but not all investigators have reported the existence of an abrupt change, a 'breakpoint', in the relation between mean tidal volume and mean inspiratory time. Different opinions exist as to whether the slope and the ...
Reisman J J - - 1988
Because of the time and the emotional cost involved in performing daily conventional chest physiotherapy in patients with cystic fibrosis, a 3-year prospective study was undertaken to compare the long-term effects of postural drainage accompanied by percussion and the forced expiratory technique with the effects of the forced expiratory technique ...
Sica A L - - 1988
In newborn pigs (4-6 days old), recordings of efferent whole hypoglossal and phrenic nerve discharges were obtained during hyperoxia (or normoxia) and during hypoxia, before and after bilateral vagotomy. With intact vagi, spontaneous hypoglossal inspiratory activity was not observed and was not elicited by either spontaneous changes of electroencephalogram (EEG) ...
Jodkowski J S - - 1988
1. Using both rectangular- and ramp-shaped intracellularly injected currents, the repetitive firing properties of 23 antidromically identified phrenic motoneurons were determined in anesthetized, paralyzed, and artificially ventilated cats during hypocapnic apnea. In response to rectangular depolarizing current injections, regular repetitive firing was observed in all cells. 2. At the beginning ...
Dodd D S - - 1988
We examined the combined effect of an increase in inspiratory flow rate and frequency on the O2 cost of inspiratory resistive breathing (VO2 resp). In each of three to six pairs of runs we measured VO2 resp in six normal subjects breathing through an inspiratory resistance with a constant tidal ...
Art T - - 1988
The exercise-induced changes in the equine breathing pattern were studied by analyzing tidal breathing flow-volume loops recorded in ten ponies both at rest and during a standardized exercise. Airflow, tidal volume, esophageal pressure and mask pressure were simultaneously recorded before, during and after a treadmill exercise. From the collected data, ...
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