Search Results
Results 401 - 450 of 1021
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Dionne I J - - 2002
We tested the reproducibility of the heart rate variability (HRV) measurements before and after a standardized meal. Heart rate recordings were obtained in 14 healthy subjects tested in a reclining position before and after a standardized meal on two separated occasions, apart by a 1-2-week interval. We measured three components ...
Monahan Kevin D - - 2002
The purpose of this study was to determine the effects of the semicircular canals and otolith organs on respiration in humans. On the basis of animal studies, we hypothesized that vestibular activation would elicit a vestibulorespiratory reflex. To test this hypothesis, respiratory measures, arterial blood pressure, and heart rate were ...
Hewitt Gwen - - 2002
A possible function of laryngeal air sacs in apes and gibbons was investigated by examining the relationships between air sac distribution, call rate, call duration and body weight in a phylogenetic context. The results suggest that lack of sacs in the smaller gibbons and in humans is a derived feature. ...
Sciacca Joslyn - - 2002
The response of infective third-stage larvae (L3) of three species of parasitic nematodes, Ancylostoma caninum, Strongyloides stercoralis, and Haemonchus contortus to carbon dioxide (CO(2)) at physiological concentrations was investigated. L3 of the skin-penetrating species, A. caninum and S. stercoralis, were stimulated by CO(2) at the concentration found in human breath ...
Delapille P P Centres d'Etudes des Transformations des APS, University of Rouen, Rouen, France. - - 2002
The aim of this study was to demonstrate the kinetics of heart rate and blood lactate level obtained after repeated short breath holds with muscular effort in a swimming pool. each subject had to perform a series of breath hold diving at rest and three series for different underwater swimming ...
Lindholm Peter - - 2002
There is indirect evidence that cardiovascular responses to apnoea result in a temporary slowing of the O(2) uptake in the lungs in exercising humans. The present study was undertaken in an attempt to determine directly to what extent this occurs, and whether the magnitude of this slowing is such that ...
Bailey E Fiona - - 2002
Pulmonary ventilation during speech breathing reflects the sum of the airflow changes used to speak and to meet the metabolic needs of the body. Studying interactions between speaking and breathing may provide insights into the mechanisms of shared respiratory control. The purposes of this study were to determine if healthy ...
Nayeri F - - 2002
Hepatocyte growth factor (HGF) is a protein produced by mesenchymal cells in many organs, which can stimulate epithelial growth. An enhanced production and concentration of HGF is observed after injuries. The lung is one of the major sources of HGF. By cooling exhaled air, a condensate is formed containing molecules ...
Rodríguez-Nieto M J - - 2002
Multiple-breath washout (MBW) tests, with end-expiratory lung volume at functional residual capacity (FRC) and 90% O(2), 5% He, and 5% SF(6) as an inspired gas mixture, were performed in healthy volunteers in supine and prone postures. The semilog plot of MBW N(2) concentrations was evaluated in terms of its curvilinearity. ...
Binks Andrew P - - 2002
Asthma evokes several uncomfortable sensations including increased "effort to breathe" and chest "tightness." We have tested the hypotheses that "effort" and "tightness" are due to perception of increased work performed by the respiratory muscles. Bronchoconstriction was induced by inhaled methacholine in 15 subjects with mild asthma (FEV(1)/FVC baseline = 81.9% ...
Nitz Jennifer - - 2002
BACKGROUND AND PURPOSE: Dystrophia myotonica or myotonic dystrophy is a progressive neuromuscular disorder in which patients demonstrate an irregular respiratory pattern and are particularly subject to cardiopulmonary compromise. The aim of the present study was to investigate the effects of both proprioceptive neuromuscular facilitation (PNF) and staged basal expansion (SBE) ...
Yeragani Vikram Kumar - - 2002
BACKGROUND: Respiratory irregularity has been previously reported in patients with panic disorder using time domain measures. However, the respiratory signal is not entirely linear and a few previous studies used approximate entropy (APEN), a measure of regularity of time series. We have been studying APEN and other nonlinear measures including ...
Lim W S - - 2002
Measurement of respiratory rate (RR) is essential in the evaluation of respiratory disorders. However, the variability in RR measurement in adults has never been adequately assessed. Respiratory rate was measured twice in 245 patients; the two measurements were performed by the same observer in 137 patients, by different observers in ...
Hirst Lisa J - - 2002
Respiratory parameters in 29 normal older subjects (mean age-73 years, SD = 5.7) were studied at rest, during single water swallows, and in continuous drinking. Respiration was recorded by intranasal air pressure changes and the moment of swallowing by pharyngoesophageal manometry. Compared with respiration at rest, respiratory rate increased immediately ...
Aboud Fionnuala Cormack - - 2002
The concept of negative intrapleural pressure is fairly new. Although the phenomenon had already been described, Wirz provided the first definitive analysis of its significance to the mechanics of breathing in 1923. By contrast, empyema has been known since antiquity; from the time of Hippocrates, treatment has consisted of open ...
Matsumoto M - - 2001
This study compared the psychological effects of Progressive Muscle Relaxation (PMR) and breathing exercises. Forty-two students were divided randomly into two groups and taught PMR or breathing exercises. Both groups practiced for five weeks and were given the Smith Relaxation States Inventory before and after each session. As hypothesized, PMR ...
Fasano V - - 2001
The aim of this study was to investigate whether patients with laryngeal hemiplegia (LH) show a frequency-dependent increase in specific airway resistance (sRaw), measured by body plethysmography. In addition to the flow-volume loop, usually considered in the functional evaluation of upper airway obstructions, variations in sRaw at respiratory frequencies of ...
Herbert N A - - 2001
Physiological characteristics of the blood oxygen transport system and muscle metabolism indicate a high dependence on aerobic pathways in the blue gourami, Trichogaster trichopterus. Haemoglobin concentration and haematocrit were modest and the blood oxygen affinity (P50=2.31 kPa at pH 7.4 and 28 degrees C) and its sensitivity to pH (Bohr ...
Breakell A - - 2001
Study objective-To investigate the correlation between the Respi-check sensor and simultaneous chest auscultation in determining the respiratory rates in adults. METHODS:Random visits to a local accident and emergency (A&E) department were made and all patients wearing oxygen masks were recruited into the study. The new sensor was attached to the ...
Zimmer M B - - 2001
To determine whether metabolic rate is suppressed in a temperature-independent fashion in the golden-mantled ground squirrel during steady state hibernation, we measured body temperature and metabolic rate in ground squirrels during hibernation at different T(a)'s. In addition, we attempted to determine whether heart rate, ventilation rate, and breathing patterns changed ...
Gessner C - - 2001
Analysis of breath condensate (BC) has received interest recently due to the need for easy and repetitive monitoring or airway and pulmonary disease. While many authors have used custom built systems, commercial systems are now available and will probably be used more widely. Early studies of markers and mediators in ...
Dellacà R L - - 2001
OBJECTIVE: To test the capability of optoelectronic plethysmography (OEP) to monitor positive end-expiratory pressure (PEEP)-induced changes of end-expiratory lung volume (EELV) changes in mechanically ventilated paralyzed patients. DESIGN: Laboratory and clinical investigation. SETTING: Intensive care unit of the Ospedale Maggiore Policlinico di Milano. PATIENTS: A total of eight patients with ...
Ward S A - - 2001
Since dyspnoeic sensation (delta) increases progressively with work rate (WR) and the duration of a volitional breath-hold (tBH) shortens, we wished to explore whether tBH might correlate sufficiently closely with delta to provide a quantitative and descriptor-free index of respiratory sensation during dynamic exercise. Nine healthy males exercised on a ...
Karl T - - 2001
Numerous publications have described measurements of breath isoprene in humans, and there has been a hope that breath isoprene analyses could be a noninvasive diagnostic tool to assess blood cholesterol levels or cholesterol synthesis rate. However, significant analytic problems in breath isoprene analysis and variability in isoprene levels with age, ...
D'Angelo E - - 2001
An index (IS), quantitating the departure of the inspiratory flow profile (IFP) from the rectangular one, i.e. the optimal profile (IS=0), was computed from pneumotachograms recorded in 26 normal, anesthetized subjects breathing spontaneously through the endotracheal tube (ETT) or face mask (FM) with or without added resistances (R) and in ...
Soparkar P - - 2001
An evaluation of the effects of ARM & HAMMER DENTAL CARE The Baking Soda Gum on extrinsic dental stain was performed on 85 subjects presenting with measurable extrinsic stain. The subjects were randomized to use either the baking soda chewing gum or a breath mint placebo once daily after lunch ...
Arambula P - - 2001
This study explores the physiological correlates of a highly practiced Kundalini Yoga meditator. Thoracic and abdominal breathing patterns, heart rate (HR), occipital parietal electroencephalograph (EEG), skin conductance level (SCL), and blood volume pulse (BVP) were monitored during prebaseline, meditation, and postbaseline periods. Visual analyses of the data showed a decrease ...
Stuessi C - - 2001
Isolated respiratory muscle endurance training (RMT) can prolong constant-intensity cycling performance. We tested whether RMT affects O2 supply during exercise, i.e. whether the partial pressure of oxygen in arterial blood (Pa,O2) and/or its oxygen saturation (SaO2) are higher during exercise after RMT than before. A group of 28 sedentary subjects ...
Roecker K - - 2001
The dilution of an intravenous bolus dose of [13C]bicarbonate is used as an estimate for the metabolic rate under certain conditions. It is a consistent finding in all studies that the total amount of intravenous [13C]bicarbonate cannot be recovered as breath 13CO2. In this study, we used a breath-by-breath analysis ...
Rocco M - - 2001
BACKGROUND: The aim of the present study was to evaluate the effects of hyperbaric oxygenation on lipid peroxidation, on the release of circulating cytokines (TNFa, IL6, IL1b) and endothelin-1 (ET1). METHODS: EXPERIMENTAL DESIGN: single arm, prospective study. SETTING: ICU hyperbaric division of a University Hospital. PATIENTS: fifteen healthy volunteers (10 ...
Mols G - - 2001
OBJECTIVE: Volume assist (VA) amplifies the breathing effort whereas pressure support ventilation (PSV) provides a fixed, effort-independent ventilatory support. According to the concept of VA, its level should compensate for the pathologically increased (additional) elastance (Eadd). However, it is unclear whether breathing subjects prefer an exact compensation of Eadd and ...
Nimmagadda U - - 2001
Various techniques of "preoxygenation" before anesthetic induction have been advocated, including tidal volume breathing (TVB) for 3-5 min, four deep breaths (DB) in 0.5 min, and eight DB in 1 min. However, no study has compared the effectiveness of these techniques, assessed extending deep breathing beyond 1 min, or investigated ...
Hyldegaard O - - 2001
The fate of bubbles formed in tissues during the ascent from a real or simulated air dive and subjected to therapeutic recompression has only been indirectly inferred from theoretical modeling and clinical observations. We visually followed the resolution of micro air bubbles injected into adipose tissue, spinal white matter, muscle, ...
Harris M B - - 2001
The roles of vagal afferent feedback in terminating inspiration and modulating breathing pattern and ventilatory responses to hypoxia and hypercapnia were assessed in the golden-mantled ground squirrel, Spermophilus lateralis, during wakefulness and urethane anesthesia. Hypoxia increased ventilation primarily through increases in breathing frequency (f(R)) while hypercapnia increased ventilation primarily through ...
Babb T G - - 2001
We previously observed an increase in minute ventilation (V E) with resistive unloading (He-O2 breathing) in healthy elderly subjects with normal pulmonary function. To investigate the effects of resistive unloading in elderly subjects with mild chronic airflow limitation (FEV(1)/FVC: 61 +/- 4%), we studied 10 elderly men and women 70 ...
Mialon P - - 2001
HYPOTHESIS: We wanted to evaluate the pulmonary effects of discontinuous oxygen breathing (15 min O2, 2 min air breaks, 15:2), at 0.25 MPa once a day for 90 min O2 (6 sequences) over 10 d. This sequence, which has never been evaluated, is currently used in our hyperbaric therapy center. ...
Tarlo S M - - 2001
Two biological sisters working at the same factory for > 9 years developed chronic beryllium disease (CBD) from a copper-beryllium alloy. Both had marked tachypnea (36 breaths/min and 45 breaths/min at rest, respectively), persisting over 8 years. Ventilation during exercise (assessed in one sibling) was grossly excessive (57 L/min, expected ...
van Lunteren E - - 2001
Respiratory motor units (MU) segregate into subpopulations, which differ in firing patterns during resting and stimulated breathing. For phrenic/diaphragm MUs, diversity also exists within subpopulations, and is greater for late than early-onset MUs. The present study characterized the extent of diversity within upper airway respiratory MU subpopulations by recording geniohyoid ...
Telles S - - 2000
The present study was conducted to evaluate a statement in ancient yoga texts that suggests that a combination of both "calming" and "stimulating" measures may be especially helpful in reaching a state of mental equilibrium. Two yoga practices, one combining "calming and stimulating" measures (cyclic meditation) and the other, a ...
Wilson R J - - 2000
While little is known of the origin of air-breathing in vertebrates, primitive air breathers can be found among extant lobe-finned (Sarcopterygii) and ray-finned (Actinopterygii) fish. The descendents of Sarcopterygii, the tetrapods, generate lung ventilation using a central pattern generator, the activity of which is modulated by central and peripheral CO(2)/H(+) ...
Duru F - - 2000
Previous studies have shown a high correlation between transthoracic impedance minute ventilation (IMV) determined by a pacemaker sensor and actual minute ventilation (VE) measured by standard methods. We hypothesized that several factors (e.g., posture, breathing pattern, and exercise type) could potentially affect the calibration between IMV and VE. In patients ...
Radhakrishna R K - - 2000
In this study, we investigated measures of nonlinear dynamics and chaos theory in regards to heart rate variability in 27 normal control subjects in supine and standing postures, and 14 subjects in spontaneous and controlled breathing conditions. We examined minimum embedding dimension (MED), largest Lyapunov exponent (LLE) and measures of ...
Nimmagadda U - - 2000
BACKGROUND: Preoxygenation before tracheal intubation is intended to increase oxygen reserves and delay the onset of hypoxemia during apnea. Various systems are used for preoxygenation. Designed specifically for preoxygenation, the NasOral system uses a small nasal mask for inspiration and a mouthpiece for exhalation. One-way valves in the nasal mask ...
Johnson A T - - 2000
Respirator dead volume accumulates exhaled carbon dioxide and returns it to the respiratory system during subsequent inhalations. Because inhaled carbon dioxide is known to be a powerful respiratory stimulant and psychoactive gas, respirator dead volume would be expected to influence performance times while respirators are worn during work. This experiment ...
Morooka H H Department of Anesthesiology, Nagasaki University School of Medicine, Japan. - - 2000
Either an increase in PaCO(2) or a decrease in PaO(2), can affect respiratory stimulation through respiratory centers, thus influencing breath-holding time (BHT). This study was designed to determine whether and how hyperbaric air could influence BHT in comparison with hyperbaric oxygen in humans. We studied 36 healthy volunteers in a ...
Harver A A Department of Psychology, University of North Carolina at Charlotte, NC 28223-0001, USA. - - 2000
We tested the hypothesis that descriptors of breathlessness represent distinct and separable cognitive constructs, and predicted that the use of descriptors of breathlessness by healthy individuals is the same as their use by patients with cardiopulmonary disease. Cluster analyses obtained in healthy individuals were compared with those obtained previously in ...
Manning T S TS Department of Kinesiology and Physical Education, Northern Illinois University, DeKalb 60115, - - 2000
The lumbar vertebrae of rowers are subjected to high levels of shear and compression at mid-drive, but intra-abdominal pressure (IAP) may partially neutralize these forces. IAP fluctuates with breathing. This study compared the IAP between inspiring during the drive and expiring during the drive. ten volunteers performed one 5x2-minute repetition ...
Jaques P A - - 2000
Ultrafine particles (< 0.10 microm in diameter) are present in great number in polluted urban air, thus posing a potential health risk. In this study, the total deposition fraction (TDF) of ultrafine aerosols with a narrow size distribution (number median diameter NMD = 0.04-0.1 microm and geometric standard deviation sigma(g) ...
Rassler B - - 2000
Coordination of the respiratory rhythm with the rhythm of limb movements has often been observed during rhythmical exercise (e.g. in locomotion). It is usually associated with changes in the respiratory time course, but not in the locomotor rhythm. Therefore, we hypothesised that in walking, the extent of coordination-related changes (CRC) ...
Halperin J - - 2000
Chasmagnathus granulatus is an estuarine crab which actively moves from subtidal to supratidal areas. To elucidate the possible existence of extrabranchial sites for aerial gas exchange, we measured respiratory and acid-base variables in animals with and without branchial water (controls and experimental crabs, respectively) during air exposure. An histological study ...
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