Search Results
Results 301 - 350 of 1010
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Lindholm Peter - - 2005
Hyperventilation prior to breath-hold diving increases the risk of syncope as a result of hypoxia. Recently, a number of cases of near-drownings in which the swimmers did not hyperventilate before breath-hold diving have come to our attention. These individuals had engaged in prolonged exercise prior to breath-hold diving and it ...
Salerno Francesco G - - 2005
The effects of breathing depth in attenuating induced bronchoconstriction were studied in 12 healthy subjects. On four separate, randomized occasions, the depth of a series of five breaths taken soon (approximately 1 min) after methacholine (MCh) inhalation was varied from spontaneous tidal volume to lung volumes terminating at approximately 80, ...
Masaoka Yuri - - 2004
Idiopathic hyperventilation (IH) is a condition of uncertain aetiology characterized by sustained arterial and alveolar hypocapnia and a plethora of symptoms, the most commonly reported being shortness of breath, and breathlessness. We previously reported that anxiety increases respiratory frequency and minute ventilation with no change in metabolism in normal subjects. ...
Reid Stephen G - - 2004
This study examined the role of phasic pulmonary stretch receptor (PSR) feedback in ventilatory control, breath clustering and breath timing in decerebrate, paralysed and artificially-ventilated cane toads (Bufo marinus) under conditions designed to minimise tonic PSR feedback. Fictive breathing was recorded as trigeminal motor output to the buccal musculature. Artificial ...
Seymour R S - - 2004
The evolution of air-breathing organs (ABOs) is associated not only with hypoxic environments but also with activity. This investigation examines the effects of hypoxia and exercise on the partitioning of aquatic and aerial oxygen uptake in the Pacific tarpon. The two-species cosmopolitan genus Megalops is unique among teleosts in using ...
Cerny Frank J - - 2004
Arm work, by limiting movement of the chest wall and use of the respiratory muscles, may alter breathing pattern and gas exchange sufficiently to interfere with the ability to perform certain tasks. To determine the effects of arm work on breathing pattern during a well-controlled work task, depth of breathing, ...
Jucá-Chagas R - - 2004
The present study investigated the respiratory rates, frequency of air breathing and ability to extract oxygen from air compared to body mass of three neotropical air-breathing fishes (Lepidosiren paradoxa, Hoplerythrinus unitaeniatus and Hoplosternum littorale) with different accessory organs, under the same conditions of hypoxia (PO(2)<5 mm Hg) and temperature (25 ...
Caron Olivier - - 2004
Body sway was studied in standing with eyes closed during quiet breathing and apnoea. The hypothesis was that absence of ventilation improved balance. Performance and control of balance were assessed by centre of gravity and centre of pressure motions respectively. Eight healthy male subjects participated in the study. The analysis ...
Pal G K - - 2004
Practice of breathing exercises like pranayama is known to improve autonomic function by changing sympathetic or parasympathetic activity. Therefore, in the present study the effect of breathing exercises on autonomic functions was performed in young volunteers in the age group of 17-19 yr. A total of 60 male undergraduate medical ...
Wang Chuji - - 2004
We report a study on the cavity ringdown spectroscopy of acetone in both the ultraviolet (UV) and the near-infrared (NIR) spectral regions to explore the potential for development of a breath analyzer for disease diagnostics. The ringdown spectrum of acetone in the UV (282.4-285.0 nm) region is recorded and the ...
Peng C-K - - 2004
OBJECTIVE: This study was designed to quantify and compare the instantaneous heart rate dynamics and cardiopulmonary interactions during sequential performance of three meditation protocols with different breathing patterns. BACKGROUND: We analyzed beat-to-beat heart rate and continuous breathing signals from 10 experienced meditators (4 females; 6 males; mean age 42 years; ...
Peppard Paul E - - 2004
STUDY OBJECTIVES: The degree to which physical exercise habits are related to sleep-disordered breathing is not known. We sought to investigate the association between a single-item exercise question and laboratory-assessed sleep-disordered breathing. DESIGN: A population-based cross-sectional epidemiologic study of adults measured the association between exercise and sleep-disordered breathing. Hours of ...
Tong Tom K - - 2004
To identify the effect of normal breathlessness sensation elicited during intense intermittent exercise at exhaustion on limitation of exercise maintenance (Ex), the contribution of the flow-resistive unloading effect of normoxic helium-oxygen breathing on the breathlessness sensation to the change in the Ex was examined. Seven men repeatedly performed 12-s exercise ...
Khayat Rami N - - 2004
We reasoned that, if the lung inflation reflex contributes importantly to apnea-induced sympathetic activation, such activation would be attenuated in bilateral lung transplant recipients (LTX). We measured muscle sympathetic nerve activity (MSNA; intraneural electrodes), heart rate, mean arterial pressure, tidal volume, end-tidal Pco(2), and arterial oxygen saturation in seven LTX ...
Cysarz Dirk - - 2004
The objective of this study was to investigate the synchronization between low-frequency breathing patterns and respiratory sinus arrhythmia (RSA) of heart rate during guided recitation of poetry, i.e., recitation of hexameter verse from ancient Greek literature performed in a therapeutic setting. Twenty healthy volunteers performed three different types of exercises ...
Bowers Emma J - - 2004
Baroreflex sensitivity is becoming an important clinical measurement. Nevertheless there is no recommend standard measurement protocol. This study assessed the ability of eight protocols to induce regular changes in cardiac beat-to-beat interval and systolic pressure (SP), and the effect each protocol had on baroreflex sensitivity (BRS). Twelve subjects had changes ...
Gurevich T Yu - - 2004
OBJECTIVE: To investigate whether the cardiac R-R interval variation (RRIV) is of value in differentiating patients with Parkinson's disease (PD) from multiple system atrophy (MSA). BACKGROUND: RRIV assessment is a simple procedure, reflecting mainly vagal efferent activity. Reduced RRIV was reported in MSA. METHODS: RRIV at rest and after 120 ...
Nikkola E M - - 2004
BACKGROUND: Only a few methods for the measurement of breathing are non-invasive and do not interfere with measured parameters. The static-charge-sensitive bed (SCSB) could be such a monitor. The aim of this study was to evaluate the validity of the SCSB compared with the respiratory inductive plethysmograph (RIP) using a ...
Larsson P U - - 2004
The purpose of this study was to investigate the validity of the MetaMax II portable metabolic measurement system against the Douglas Bag technique. Nine recreationally active male subjects were included in a validation at 100 W, 10 well-trained male subjects at 200 W and 10 well-trained males at 250 W ...
Reychler Gregory - - 2004
BACKGROUND: So-called intrapulmonary percussive ventilation (IPV), frequently coupled with a nebulizer, is increasingly used as a physiotherapy technique; however, its physiologic and clinical values have not been rigorously assessed. STUDY OBJECTIVE: To compare in vitro and in vivo characteristics of the nebulizer of the IPV device (Percussionaire; Percussionaire Corporation; Sandpoint, ...
Dellacà R L - - 2004
Expiratory flow limitation (EFL) during tidal breathing is a major determinant of dynamic hyperinflation and exercise limitation in chronic obstructive pulmonary disease (COPD). Current methods of detecting this are either invasive or unsuited to following changes breath-by-breath. It was hypothesised that tidal flow limitation would substantially reduce the total respiratory ...
Connaghan Kathryn P KP Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98105-6246, - - 2004
The development of respiratory drive for vocalization was studied by observing chest wall kinematics longitudinally in 4 typically developing children from the age of 9 to 48 months. Measurements of the relative contribution of rib cage and abdominal movement during vocalization (i.e., babbling and true words) and rest breathing were ...
Ben Lamine Samia - - 2004
To investigate the interindividual differences in respiratory sinus arrhythmia (RSA), recordings of ventilation and electrocardiogram were obtained from 12 healthy subjects for five imposed breathing periods (T(TOT)) surrounding each individual's spontaneous breathing period. In addition to the spectral analysis of the R-R interval signal at each breathing period, RSA characteristics ...
Beck Jennifer - - 2004
Mechanical ventilation may interfere with the spontaneous breathing pattern in infants because they have strong reflexes that play a large role in the control of breathing. This study aimed to answer the following questions: does a ventilator-assisted breath 1) reduce neural inspiratory time, 2) reduce the amplitude of the diaphragm ...
Leaf David Alexander - - 2004
PURPOSE: The purpose of this study was to compare the susceptibility to exercise-induced lipid peroxidation of patients on chronic maintenance dialysis (CMD) and non-CMD control subjects. DESIGN: Cross-sectional comparison of exercise-induced changes in breath ethane and pentane flux between patients on CMD (group A) and an age-, gender-, medical diagnosis-, ...
Risberg J - - 2004
An initial occupational survey (OS) was initiated to investigate the prevalence of venous gas embolism (VGE) in chamber attendants assisting hyperbaric oxygen (HBO2) treatments. Nine female subjects were exposed for three consecutive days to the routine hospital procedure of compressed air exposure to 240 kPa for approximately 115 min with ...
Schneider Rainer - - 2003
When electrodermal activity (EDA) recordings are controlled for artifacts, i.e., electrodermal reactions [EDRs] elicited by breathing irregularities, several problems arise. For example, respiration is difficult to evaluate because there are no clear-cut criteria for its values, e.g., wave form, depth. Furthermore, respiration and EDA are rather complexly intertwined, and there ...
Pilmanis Andrew A - - 2003
INTRODUCTION: The current extravehicular activity (EVA) space suit at 4.3 psia causes hand and arm fatigue and is too heavy for Martian EVA. A 3.5 psia EVA pressure suit requires increased preoxygenation time but would reduce structural complexity, leak rate, and weight while increasing mobility, comfort, and maintainability. On Mars, ...
Nicol Stewart - - 2003
Resting non-hibernating echidnas are characterised by low metabolic rates, but also have a very low respiratory frequency and a variable respiratory minute volume, often resulting in low levels of arterial O(2) and high CO(2). As the echidna lies at one physiological extreme among the hibernators, in terms of its large ...
Eves Neil D - - 2003
Maximal exercise performance is decreased when breathing from a self-contained breathing apparatus (SCBA), owing to a ventilatory limitation imposed by the increased expiratory resistance. To test the hypothesis that decreasing the density of the breathing gas would improve maximal exercise performance, we studied 15 men during four graded exercise tests ...
Houtveen Jan H - - 2003
OBJECTIVE: This study tested whether functional somatic symptoms are associated with exaggerated increases in self-reported anxiety and somatic complaints in response to stress and CO(2)-enriched air breathing, and whether this association exists in parallel to or in the absence of exaggerated physiological responses. METHODS: Out of 499 young somatically healthy ...
KopczyƄska Beata - - 2003
Mediation of the respiratory reflex effects of an exogenous serotonin challenge goes beyond the lung vagi and is suggested to involve the nodose ganglia. In the present experiments the effects of an intravenous serotonin challenge on breathing pattern were studied in 8 pentobarbitone-chloralose anaesthetised cats. Bolus injection of serotonin oxalate ...
Simon Ron - - 2003
Respiration rate (RR) and minute ventilation (MV) provide important clinical information on the state of the patient. This study evaluated the accuracy of determining these using a pacemaker impedance sensor. In 20 patients who were previously implanted with a Guidant PULSAR MAX group of pacemakers, the telemetered impedance sensor waveform ...
Proquitté H - - 2003
BACKGROUND: Perfluorocarbon (PFC) has been widely used in the treatment of respiratory diseases; however, PFC content of the breathing gases remains unknown. Therefore, we developed an absorber using PFC selective zeolites for PFC measurement in gases and investigated its accuracy. METHODS: To generate a breathing gas with different PFC contents ...
Aquino-Parsons C - - 2003
AIM: To investigate the influence of deep inspiration breath-hold on the oxygen tension of in-vivo tumours measured using an Eppendorf pO2 histograph. MATERIALS AND METHODS: Patients with accessible primary or metastatic tumours > or = 2 cm diameter were entered into a protocol measuring tumour oxygenation with an Eppendorf pO2 ...
Sexauer William P - - 2003
OBJECTIVES: Cardiopulmonary exercise testing in cystic fibrosis (CF) patients is useful to assess functional status and prognosis. Using the current interpretation guidelines, the utility of this testing will be limited in those patients who cannot exercise to a near-maximal level. This study investigates the utility of the breathing reserve index ...
Eves Neil D - - 2003
BACKGROUND: The self-contained breathing apparatus (SCBA) used by firefighters, and other working in dangerous environments, adds an external resistance to expiration, which increases expiratory work during heavy exercise. HYPOTHESIS: Compressed air is typically used with the SCBA and we hypothesized that changing the inspired oxygen concentration and/or gas density with ...
Pandit Jaideep J - - 2003
BACKGROUND: Three common methods for preoxygenation are 3 min of tidal breathing, four deep breaths taken within 30 s (4DB), and eight deep breaths taken within 60 s (8DB). This report compares these three techniques in healthy volunteers. METHODS: Five healthy subjects breathed through a mouthpiece and wore a nose ...
Haverkamp Hans - - 2003
A 22-year-old competitive female cyclist complained of cough, chest tightness, and wheeze during high-intensity exercise that had previously been diagnosed as exercise-induced bronchospasm (EIB). A loud stridor, a sensation of her "throat closing," and severe dyspnea developed during maximal cycling exercise with concomitant reductions in both inspiratory and expiratory flow ...
Ritz Thomas - - 2003
Breathing exercises are frequently recommended as an adjunctive treatment for asthma. A review of the current literature found little that is systematic documenting the benefits of these techniques in asthma patients. The physiological rationale of abdominal breathing in asthma is not clear, and adverse effects have been reported in chronic ...
Landberg Tobias - - 2003
The limb girdles and lungs of turtles are both located within the bony shell, and therefore limb movements during locomotion could affect breathing performance. A mechanical conflict between locomotion and lung ventilation has been reported in adult green sea turtles, Chelonia mydas, in which breathing stops during terrestrial locomotion and ...
Van Houtte Siska - - 2003
Isocapnic hyperpnoea has been shown to reliably produce fatigue of the diaphragm. The aim of the present study was to investigate whether incremental isocapnic hyperpnoea (IH(incr)) impairs the arm exercise performance and alters the breathing pattern during subsequent maximal incremental arm cranking. Nine healthy volunteers performed an arm cranking test ...
Joulia Fabrice - - 2003
Repeated epochs of breath-holding were superimposed to the regular training cycling program of triathletes to reproduce the adaptative responses to hypoxia, already described in elite breath-hold divers [Respir. Physiol. Neurobiol. 133 (2002) 121]. Before and after a 3-month breath-hold training program, we tested the response to static apnea and to ...
Tattersall Glenn J - - 2003
To examine the changes in breathing that occur during progressive hypothermia and rewarming in neonatal rats, we cooled and rewarmed rat pups during the first 6 days of life. During cooling, breathing stopped when rectal temperature (Tr) fell below 10.7+/-0.24 degrees C, and recovered spontaneously during rewarming when Tr reached ...
Lafortuna Claudio L - - 2003
Twenty-four Mediterranean fin whales were tracked in open sea with a method based on the assessment of the animal differential position in respect of the observer's absolute position aboard a vessel, with the concomitant recording of the respiratory activity. Short distance video recording was also performed in two whales, permitting ...
Finnoff Jonathan T - - 2003
OBJECTIVES: To compare the magnitudes of change in heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure, and rate-pressure product (RPP) during 3 abdominal exercises: straight partial sit-up (SPSU), oblique partial sit-up (OPSU), and the AbSculptor(R) sit-up; and to examine the effect of breath holding on ...
Singhi Sunit - - 2003
The World Health Organization's global programme for the control of acute respiratory infections relies on counting respiratory rate (RR) by observing abdominal and chest movements in order to diagnose pneumonia. However, few studies on the reliability of the observation method have been published. We counted RR simultaneously by observation and ...
Wilson Rory P - - 2003
Humboldt penguins Spheniscus humboldti in captivity and free-living Magellanic penguins S. magellanicus were fitted with loggers to determine beak angles during breathing. The Humboldt penguins were also fitted with masks for determining rates of air flow during breathing. During periods of higher gas exchange requirement, Humboldt penguins opened their beaks ...
Jones Alice Y M - - 2003
BACKGROUND AND PURPOSE: The oxygen demand of breathing exercises and the clinical implications have not been studied in detail. In this study, the oxygen cost of 3 common breathing exercises believed to reduce oxygen cost (ie, work of breathing) was compared with that of spontaneous breathing in patients with chronic ...
Wauer Juliane - - 2003
Ultrasonic transit-time airflow meters (UFM) allow simultaneous measurements of volume flow V'(t) and molar mass MM(t) of the breathing gas in the mainstream. Consequently, by using a suitable tracer gas the functional residual capacity (FRC) of the lungs can be measured by a gas wash-in/wash-out technique. The aim of this ...
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