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Results 251 - 300 of 1010
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Verges Samuel - - 2006
Inspiratory muscle fatigue (IMF) can develop during exhaustive exercise and cause tachypnea or rapid shallow breathing. We assessed the effects of rib cage muscle (RCM-F) and diaphragm fatigue (DIA-F) on breathing pattern and respiratory mechanics during high-intensity endurance exercise. Twelve healthy subjects performed a constant-load (85% maximal power) cycling test ...
Gagnon Caroline - - 2006
PURPOSE: Ideally, preoxygenation is performed using a tight fitting mask either by breathing normally for three to five minutes or with four to eight vital capacity (VC) breaths in 0.5 to one minute, but in practice leaks are frequent and sometimes unavoidable. This study was designed to determine which breathing ...
Di Rienzo Marco - - 2006
A new textile-based wearable system, named MagIC (Maglietta Interattiva Computerizzata) has been recently developed for getting unobtrusive recordings of cardiorespiratory and motion signals during spontaneous behavior. The system is composed of a vest, including textile sensors for ECG and breathing frequency detection, and a portable electronic board for motion assessment, ...
Reychler G - - 2006
The intrapulmonary percussive ventilation (IPV), frequently coupled with a nebulizer, is increasingly used as a physiotherapy technique; however, its physiologic and clinical values have been poorly studied. The aim of this study was to compare lung deposition of amikacin by the nebulizer of the IPV device (Percussionaire; Percussionaire Corporation; Sandpoint, ...
Gebber Gerard L - - 2006
The present study was designed to characterize respiratory fluctuations in awake, healthy humans under resting conditions. Specifically, we used Allan factor and dispersional analysis to test whether the fluctuations in breath number, respiratory period, and breath amplitude were fractal or random in nature. The results can be summarized as follows. ...
Fabre N - - 2006
This study aimed (i) to quantify the spontaneous coordination between breathing and hand rim wheelchair propulsion, (ii) to manipulate arm movement frequency and assess its effects on spontaneous coordination, and (iii) to investigate the hypothesis that entrainment of breathing improves economy of locomotion and leads to a lower rate of ...
Keong Chen Chee CC Sports Science - - 2006
This study investigates the effects of tocotrienol-rich palm vitamin E supplementation on exercise-induced lipid peroxidation and endurance performance in the heat. In a double blind, cross-over study, eighteen healthy, male recreational athletes completed two endurance running trials, until exhaustion, on a motorized treadmill at 70% VO2max on two separate occasions ...
Mörk Anna-Karin - - 2006
Physiologically based toxicokinetic (PBTK) modeling of human experimental data suggests difficulties to simultaneously describe the time courses of inhaled polar solvents in blood and breath, especially if exposures occur during physical exercise. We attribute this to the washin-washout effect in the airways. The aim was to develop a PBTK-model that ...
Narkiewicz Krzysztof - - 2006
Respiration contributes importantly to short-term modulation of sympathetic nerve activity. However, the relationship between spontaneous breathing rate, chemoreflex function, and direct measures of sympathetic traffic in healthy humans has not been studied previously. We tested the hypothesis that muscle sympathetic nerve activity and chemoreflex sensitivity are linked independently to respiratory ...
Hagins Marshall - - 2006
Anecdotal evidence suggests that people hold their breath during lifting tasks in order to increase intra-abdominal pressure (IAP) and thereby increase lumbar stability. Studies have shown that voluntary control of the breath influences IAP and that increases in IAP are related to increases in lumbar stability. However, a description of ...
Yetkin Ertan - - 2006
It has been reported that deep breathing at 6 breaths/min is associated with reduction of premature ventricular complexes. The beneficial effect of deep breathing is supposed to be due to vagal modulation of sinoatrial and atrioventricular node. Beside the modulating effects of deep breathing, we believe that deep breathing, which ...
Riecke Björn - - 2005
BACKGROUND: The nondispersive isotope-selective infrared spectroscopy (NDIRS) is a valid method for the measurement of the 13CO2:12CO2 ratio in breath samples. Methodical influences have to be considered to obtain valid results. AIM: To evaluate the effect of oxygen supply to patients on the measurement of 13C:12C ratio in breath samples ...
Barbosa T M - - 2005
The purpose of this study was to identify the relationship between the bioenergetical and the biomechanical variables (stroke parameters), through a range of swimming velocities, in butterfly stroke. Three male and one female butterflier of international level were submitted to an incremental set of 200-m butterfly swims. The starting velocity ...
Galy O - - 2005
To determine whether exercise modality affects arterial hypoxemia (EIAH) during training-intensity exercise, 13 triathletes performed 20 min of cycling (C) followed by 20 min of running (R): C-R, and two weeks later, 20 min of R followed by 20 min of C:R-C. Each trial was performed at an intensity slightly ...
West Erin - - 2005
STUDY OBJECTIVES: To determine if the concentration of nitric oxide (NO) in the lungs increases with hyperpnea by contrasting calculated production (ie, the product of the fractional expired NO concentration [FeNO] and minute ventilation [Ve]) [Vno] with the amount of NO in equilibrium with the conducting airways (eNOair) and the ...
Westerdahl Elisabeth - - 2005
STUDY OBJECTIVES: To investigate the effects of deep-breathing exercises on pulmonary function, atelectasis, and arterial blood gas levels after coronary artery bypass graft (CABG) surgery. DESIGN, SETTING, AND PATIENTS: In a prospective, randomized trial, patients performing deep-breathing exercises (n = 48) were compared to a control group (n = 42) ...
Marntell Stina - - 2005
OBJECTIVES: To compare pulmonary function and gas exchange in anaesthetized horses during and after breathing either O2-rich gas mixtures or air. ANIMALS: Six healthy standard bred trotters (age range 3-12 years; mass range 423-520 kg), four geldings and two mares. Study design Randomized, cross-over experimental study. METHODS: Horses were anaesthetized ...
Kamboures M A - - 2005
We have determined the concentrations of carbonyl sulfide (OCS), dimethylsulfide, and carbon disulfide (CS(2)) in the breath of a group of cystic fibrosis (CF) patients and one of healthy controls. At the detection sensitivity in these experiments, room air always contained measurable quantities of these three gases. For each subject ...
Vangesselen Steven - - 2005
Oscillatory changes in parameters of gas exchange have been reported during rest and exercise in cardiac patients with severely depressed left ventricular function. As a result of the growing interest in this oscillatory phenomenon, several methods for assessment of this ventilatory response have been presented in cardiovascular research. Nowadays, objective ...
Darquenne Chantal - - 2005
Convective mixing (CM) refers to the different transport mechanisms except Brownian diffusion that irreversibly transfer inspired air into resident air and can be studied using aerosol bolus inhalations. This paper provides a review of the present understanding of how each of these mechanisms contributes to CM. Original data of the ...
Villard Sébastien - - 2005
We explored the locomotor respiratory coupling (LRC) during a 50-min constant-load submaximal cycling exercise. A 4-week recombinant human erythropoietin (r-HuEPO) treatment improved participants' aerobic capabilities, but did not elicit significant changes in LRC. The distributions of the respiratory frequency over pedalling frequency ratios were systematically bimodal, with a preferred use ...
Barnai Maria - - 2005
Rehabilitation including physiotherapy is an important part of the treatment used to help improve the quality of life of patients with cystic fibrosis (CF). The aim of this study was to determine the value of the breath-hold time as an index of exercise tolerance in patients with CF. Eighteen patients ...
Hoffmann U - - 2005
Breath holding maneuvers induce hypoxia, hypercapnia, and various cardiovascular responses typically including increases in total peripheral resistance, mean arterial pressure (MAP) and decreases in heart rate (HR). During dynamic exercise these responses may have a generally negative impact on performance. Moreover, they deserve particular attention in cardiovascular risk subjects. In ...
de Mayo T - - 2005
The objective of this study was to determine the effects of breathing type and body position on sternocleidomastoid and suprahyoid electromyographic (EMG) activity. The sample included 18 subjects with upper costal breathing type (study group) and 15 subjects with costo-diaphragmatic breathing type (control group). All individuals had natural dentition and ...
Affonso E G - - 2005
The present study analyzes the respiratory responses of the neotropical air-breathing fish Hoplosternum littorale to graded hypoxia and increased sulfide concentrations. The oxygen uptake (VO2), critical O2 tension (PcO2), respiratory (fR) and air-breathing (fRA) frequencies in response to graded hypoxia were determined for fish acclimated to 28 degrees C. H. ...
Lemaître F - - 2005
The diving response elicited by breath-holding (BH) and immersion mainly consists of bradycardia, decreased cardiac output, and peripheral vasoconstriction. These responses reduce oxygen consumption and thereby prolong the duration of the dive. They may also lead to cardiac arrhythmias or hypoxia, however, which in turn may play a role in ...
Plathow Christian - - 2006
To assess the stability and reproducibility of different breath-hold levels in healthy volunteers and patients using dynamic MRI (dMRI). In ten healthy volunteers and ten patients with pulmonary hypertension (PH) and normal lung function craniocaudal intrathoracic distances (CCD) were measured during inspiratory and expiratory breath-hold (15 s) (in healthy volunteers ...
Cysarz Dirk - - 2005
The impact of meditation on cardiorespiratory synchronization with respect to breathing oscillations and the modulations of heart rate induced by respiration (respiratory sinus arrhythmia, RSA) was investigated in this study. Four different exercises (spontaneous breathing, mental task, Zen meditation, and Kinhin meditation) were consecutively performed by nine subjects mainly without ...
Ardigo' L P - - 2005
The aim of this study was to investigate metabolic demand and mechanical work of different basketball wheelchairs that represented significant stages of its evolution from 1960 to date. Four subjects pushed each model on a basketball court at different speeds (from 0.90 to 2.35 m.s(-1)). During the trials, oxygen consumption ...
Luijendijk S C M - - 2005
We determined the argon (Ar) isotope ratio in samples of expired alveolar gas gathered during Ar washout from residual gas relative to this ratio in samples of expired alveolar gas gathered just before the beginning of this washout in 13 young, healthy human subjects at rest. These data were determined ...
Hall Roberta L - - 2005
This research tests the relative ability of body size factors and sex to explain variation in nose volume and to explain metabolic measures during rest and moderate exercise in 50 young adults. It uses standard anthropometric measures plus two new measures of nose morphology (nose/face angle and nose volume) and ...
Natalini G - - 2005
BACKGROUND: The power of breathing (PoB) is used to estimate the mechanical workload of the respiratory system. Aim of this study was to investigate the effect of different tidal volume-respiratory rate combinations on the PoB when the elastic load is constant. In order to assure strict control of the experimental ...
Delahoche J - - 2005
Breath-holding induces cardiovascular responses, notably bradycardia and peripheral vasoconstriction, which are known collectively as the diving response. This response is oxygen-conserving, i.e. an augmented response attenuates arterial oxygen desaturation, and is enhanced by apnoea training. To test this hypothesis, we compared heart rate (HR) and arterial oxygen saturation (SaO (2)) ...
Tusman G - - 2005
The objective of this study was to evaluate the effects of lung perfusion on the slopes of phases II (S(II)) and III (S(III)) of a single-breath test of CO(2) (SBT-CO(2)). Fourteen patients submitted to cardiac surgery were studied during weaning from cardiopulmonary bypass (CPB). Pump flow was decreased in 20% ...
Hodgson M D - - 2005
Processes controlling aroma release and delivery during and after the consumption of a beverage were studied using real-time physiological and aroma release measurements. The key processes were as follows. During swallowing, a portion of the buccal gas phase was transferred first to the throat and then to the nasal passages ...
Petropoulos Ioannis K - - 2005
PURPOSE: To evaluate whether prostaglandins are mediators of the hypercapnia-associated vasodilation of the optic nerve head vessels. METHODS: We measured the PO(2) at intervascular areas of the optic disc in 9 anaesthetized miniature pigs using oxygen-sensitive microelectrodes placed at <50 mum from the optic disc. PO(2) was measured continuously under ...
Kluess Heidi A - - 2005
BACKGROUND: The exercise pressor reflex is thought to be an important cardiovascular control mechanism that may be compromised in disease states such as congestive heart failure and other metabolic syndromes. The purpose was to describe the exercise pressor reflex by observing heart rate variability and blood pressure responses to handgrip-exercise ...
Mansy H A - - 2005
Endotracheal tubes (ETTs) are used to establish airway access in patients with ventilatory failure and during general anaesthesia. Tube malpositioning can compromise respiratory function and can be associated with increased morbidity and mortality. Clinical assessment of ETT position normally involves chest auscultation, which is highly skill-dependent and can be misleading. ...
Montmerle Stéphanie - - 2005
We hypothesized that the perfusion heterogeneity in the human, upright lung is determined by nongravitational more than gravitational factors. Twelve and six subjects were studied during two series of parabolic flights. We used cardiogenic oscillations of O(2)/SF(6) as an indirect estimate of intraregional perfusion heterogeneity (series 1) and phase IV ...
Mortola Jacopo P - - 2005
In cattle, sheep and goats, during resting conditions, breathing frequency (f) greatly exceeds the value expected for their body weight (W, kg) from the allometric curve of other land mammals. It was postulated that this was the effect of the production of CO2 during rumen fermentation. If this were the ...
West Bruce J - - 2005
To test the hypothesis that the fractal character of breathing and heart rate are independent, inter-breath intervals (IBI) and R-R intervals (RRI) were measured during rest and two levels of exercise at 1 and 2.8 ATA in a hyperbaric chamber in 18 male and female subjects (ages 19-74 years). Both ...
Weiskopf Richard B - - 2005
OBJECTIVE: Acute anemia slows the responses to clinical tests of cognitive function. We tested the hypothesis that these slowed responses during acute severe isovolemic anemia in healthy unmedicated humans result from impaired central processing. METHODS: A blinded operator measured the latency of the P300 peak in nine healthy volunteers at ...
Bell Harold J - - 2005
Increased wakefulness is known to suppress the initial ventilatory response to passive movement and the steady-state ventilatory response to exercise. However, the effect of increased wakefulness upon the integrated ventilatory response at the onset of exercise is not known. We hypothesized that increasing wakefulness via a cognitive task would attenuate ...
Todd David C - - 2005
BACKGROUND: We have observed that dosimeter-run nebulizers have a much smaller output when manually activated than when breath activated; however, this has not been adequately investigated. OBJECTIVE: To evaluate the effect of different calibration methods on nebulizer output. METHODS: Six healthy subjects performed all calibrations. The nebulizers were operated by ...
Cone David C - - 2005
OBJECTIVES: Carboxyhemoglobin (COHb) levels can be estimated by chemical analysis of exhaled alveolar breath. Such noninvasive measurement could be used on the fireground to screen both firefighters (FFs) and victims. The purpose of this study was to assess the feasibility of using a hand-held carbon monoxide (CO) monitoring device to ...
Chkaidze M - - 2005
Inhaled Nitric oxide is a selective and potent pulmonary vasodilator with minimal influence on systemic vascular resistance. Due to these properties NO becomes widespread treatment for pulmonary hypertension of different etiologies. However, during inhalation via inspiratory limb of breathing circuit NO reacts with oxygen, producing nitrogen dioxide (NO2) which is ...
Perkins Gavin D - - 2005
BACKGROUND: Current international resuscitation guidelines for lay people rely on the assessment of "normal breathing" as a key sign of breathing and circulation. However, it is not known how accurately laypersons can discriminate between "normal" and "abnormal" breathing. The aim of this study was to test the ability of medical ...
Hustad John T P - - 2005
OBJECTIVE: The purpose of this study is to determine the accuracy of retrospective estimated blood alcohol concentrations (eBACs) for re-creating intoxication resulting from a naturally occurring drinking event. This study identified five eBAC equations, applied them to self-report data and compared the results to actual blood alcohol concentration obtained by ...
Thakkar Kalpesh - - 2005
BACKGROUND: Diarrhea is a common problem in critically ill patients. Our patients are fed a high-carbohydrate enteral formula. We hypothesized that diarrhea in our patients may be related to the osmotic effects of unabsorbed carbohydrate in the small intestine and colon. METHODS: We studied 19 patients, 3 months to 17 ...
Barbosa Tiago M - - 2005
The purpose of this study was to examine the relationship between the intra-cycle variation of the horizontal velocity of displacement (dV) and the energy cost (EC) in butterfly stroke. Five Portuguese national level swimmers performed one maximal and two sub-maximal 200-m butterfly swims. The oxygen consumption was measured breath-by-breath by ...
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