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Wüst Rob C I - - 2008
When measuring breath-by-breath (BbB) oxygen uptake at the mouth (V MO2 ) as the difference between the amount of inspired and expired oxygen, BbB variation in lung oxygen stores due to BbB variation in end-expiratory lung volume (VLET) introduces an error leading to a decreased signal-to-noise ratio when compared to ...
Lundby C - - 2008
This study was performed to test the hypothesis that administration of recombinant human erythropoietin (rHuEpo) in humans increases maximal oxygen consumption by augmenting the maximal oxygen carrying capacity of blood. Systemic and leg oxygen delivery and oxygen uptake were studied during exercise in eight subjects before and after 13 wk ...
Krishna Rao Dasari V - - 2008
The impact of different levels of agitation speed, carbondioxide and dissolved oxygen concentration on the key parameters and production of rhG-CSF in Escherichia coli BL21(DE3)PLysS were studied. Lower carbondioxide concentrations as well as higher agitation speeds and dissolved oxygen concentrations led to reduction in the acetate concentrations, and enhanced the ...
Alcaraz-García M J - - 2008
Oxygen toxicity is a problem in diving which can have fatal consequences in the water. When divers use closed-circuit oxygen rebreathing apparatus they are taking only oxygen 100% and this hyperoxic exposure increases the generation of reactive oxygen species (ROS) in biological tissues. The objective of the present study is ...
Borghi-Silva A - - 2008
BACKGROUND: Respiratory muscle unloading during exercise could improve locomotor muscle oxygenation by increasing oxygen delivery (higher cardiac output and/or arterial oxygen content) in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixteen non-hypoxaemic men (forced expiratory volume in 1 s 42.2 (13.9)% predicted) undertook, on different days, two constant work ...
McGaw Iain J - - 2008
The gastric physiology of the Dungeness crab, Cancer magister, was investigated over a range of oxygen tensions. Postprandial crabs reacted differently to hypoxia compared with unfed animals. The bradycardic response in postprandial animals was reduced, suggesting a summation of responses with feeding. A similar pattern was observed for ventilation rate. ...
Stramma Lothar - - 2008
Oxygen-poor waters occupy large volumes of the intermediate-depth eastern tropical oceans. Oxygen-poor conditions have far-reaching impacts on ecosystems because important mobile macroorganisms avoid or cannot survive in hypoxic zones. Climate models predict declines in oceanic dissolved oxygen produced by global warming. We constructed 50-year time series of dissolved-oxygen concentration for ...
Liu K Ruth - - 2008
Oxygenation changes in the left prefrontal cortex during language processing were assessed with near-infrared spectroscopy (NIRS). Oxyhemoglobin and deoxyhemoglobin concentrations at the Fp1 site during 5 min of resting with eyes closed (control), followed by 5 min of reading aloud, were monitored. A statistically significant change in the oxyhemoglobin concentration ...
Wang Alice - - 2008
Melanin, a major pigment found in retinal pigment epithelium (RPE) cells, is considered to function in dual roles, one protective and one destructive. By quenching free radical species and reactive oxygen species (ROS) melanin counteracts harmful redox stress. However, melanin is also thought to be capable of creating ROS. In ...
Crawford D M - - 2008
Following an explosion on board a British Navy submarine operating under the Polar ice cap, a 33-year-old sailor fought a fire without protective breathing apparatus. He was found confused, with soot about his nares. A suspected diagnosis of carbon monoxide (CO) poisoning was rapidly confirmed on site using a new ...
Nasilowski Jacek - - 2008
BACKGROUND: Differences in oxygen delivery between portable oxygen concentrators (POC) and liquid oxygen (LO) portable units, pose a question if POCs are equally effective as LOs in reducing exercise-induced hypoxaemia. DESIGN: Randomized, single-blind clinical trial. PATIENTS: Thirteen COPD patients (means: age 66+/-11 year, FEV(1) 35.2+/-13.7% predicted) and respiratory failure (means: ...
Frappell Peter B - - 2008
The 'supply' of substrates should match 'demand' for energy utilization and not limit it. Integration of supply to demand would be expected to occur during ontogeny. As a result of a short gestation and protracted lactation most development in marsupials occurs ex utero in a thermally stable pouch, hence there ...
Hale Tudor - - 2008
This paper provides a thumb-nail sketch of some of the key issues that have been instrumental in the development of the scientific study of exercise, and more particularly sports, physiology. Those who have had the pleasure of reading the American Physiological Society's publication Exercise Physiology in its "People and Ideas" ...
Bianchini Jr I - - 2008
This study presents a kinetic model of oxygen consumption during aerobic decomposition of detritus from seven species of aquatic macrophytes: Cabomba furcata, Cyperus giganteus, Egeria najas, Eichhornia azurea, Salvinia auriculata, Oxycaryum cubense and Utricularia breviscapa. The aquatic macrophytes were collected from Oleo Lagoon situated in the Mogi-Guaçu river floodplain (SP, ...
Riser Stephen C - - 2008
The question of whether the plankton communities in low-nutrient regions of the ocean, comprising 80% of the global ocean surface area, are net producers or consumers of oxygen and fixed carbon is a key uncertainty in the global carbon cycle. Direct measurements in bottle experiments indicate net oxygen consumption in ...
Sloman Katherine A - - 2008
Animals living in the intertidal zone experience regular, predictable fluctuations in physical parameters including temperature, oxygen and salinity and rely on behavioural, physiological and biochemical mechanisms to cope with environmental variation. In the present study, behavioural strategies induced by aquatic hypoxia (e.g. emergence) were performed at similar oxygen tensions across ...
Hamling A E - - 2008
The objective of this study was to determine the retail shelf stability of beef chuck and round muscles enhanced with ammonium hydroxide, salt, and carbon monoxide. A split plot design was used for each of 3 muscles [triceps brachii (TB), biceps femoris (BF), and rectus femoris (RF)] with 2 treatments ...
Ijeri Vijaykumar S - - 2008
Active spatial and temporal modulation of domains of singlet oxygen activity is demonstrated using electrochemical tools. Using singlet oxygen microscopy in photosensitized experiments, it is shown that singlet oxygen concentrations around an ultramicroelectrode can be controlled by applying a bias voltage to the electrode. Two phenomena that can be exploited ...
Skjodt Neil M - - 2008
BACKGROUND: The inspired oxygen to pulse saturation (SpO2:PIO2) curve mirrors the oxyhaemoglobin dissociation curve but is shifted to the right by the difference between inspired and alveolar oxygen fractions. Inspection of the curve has been used to discern changes in shunt. AIMS: We aimed to demonstrate the SpO2: PIO2 curve's ...
Filoche Marcel - - 2008
The gas transport in the acinus is limited at rest by the finite oxygen diffusivity. Although the simplest steady-state model of diffusion permits understanding a number of observations, it fails to quantitatively fit the value of the absolute flux of oxygen at rest and exercise. In this paper, we show ...
Saga Norio N Department of Exercise Physiology, Graduate School of Health and Sports Science, Juntendo University , Chiba, - - 2008
The purpose of this study was to clarify whether heat preconditioning results in less eccentric exercise-induced muscle damage and muscle soreness, and whether the repeated bout effect is enhanced by heat preconditioning prior to eccentric exercise. Nine untrained male volunteers aged 23 ± 3 years participated in this study. Heat ...
Imlay James A JA Department of Microbiology, University of Illinois, Urbana, IL 61801, USA. - - 2008
Life evolved in an anaerobic world; therefore, fundamental enzymatic mechanisms and biochemical pathways were refined and integrated into metabolism in the absence of any selective pressure to avoid reactivity with oxygen. After photosystem II appeared, environmental oxygen levels rose very slowly. During this time, microorganisms acquired oxygen tolerance by jettisoning ...
Heyne Belinda - - 2008
Two new sensors for the detection of reactive oxygen species have been synthesized and characterized; they contain the 4-amino-7-nitrobenzofurazan (ABF) moiety covalently tethered to a phenol. Comparison of sensors ABFhd and dABFhd (the latter containing two ortho-methyl groups) shows that introduction of steric bulk leads to an improvement of fluorescent ...
Freishtat Robert J RJ Division of Emergency Medicine, Children's National Medical Center, Washington, DC 20010, USA. - - 2007
There are no studies evaluating the epidemiology of pediatric acute lung injury (ALI) in the emergency department (ED), where early identification and interventions are most likely to be helpful. The purpose of this study was to describe the epidemiology of the ALI precursor acute hypoxemic respiratory failure (AHRF) in the ...
Nagasawa T - - 2008
Little is known about the effect of exercise intensity on post-exercise oxygen consumption in nonexercising muscle. This study examined the effect of exercise intensity on muscle oxygen consumption (VO2mus) in nonexercising forearm flexor muscles (nonexVO2mus) after cycling exercise. Eight healthy male subjects performed 20 min of cycling exercise at 30%, ...
Brunelli Alessandro - - 2008
OBJECTIVE: Non-univocal conclusions have been published regarding the definition of oxygen desaturation in relation to postoperative outcome. We aimed to verify whether oxygen desaturation during a maximal stair-climbing test was associated with postoperative cardiopulmonary complications and to assess which definition of oxygen desaturation (oxygen saturation <90% or desaturation >4% with ...
Samorì Chiara - - 2007
Room-temperature ionic liquids (RTILs) recently have generated great interest as a result of their potential commercial applications. In particular, because of their negligible vapor pressure and low inflammability, they have been suggested as green alternatives to traditional organic solvents. The toxicity and potential environmental risk of this heterogeneous class of ...
Ali Khalid - - 2007
BACKGROUND: Hypoxia is common after acute stroke. Most studies of oxygenation after stroke were done at night. The objective of this study was to determine whether there are differences in oxygenation between day and night early after stroke. METHODS: Patients with an acute stroke were recruited within 24 hours of ...
Secher Neils H - - 2008
During exercise: the Kety-Schmidt-determined cerebral blood flow (CBF) does not change because the jugular vein is collapsed in the upright position. In contrast, when CBF is evaluated by (133)Xe clearance, by flow in the internal carotid artery, or by flow velocity in basal cerebral arteries, a approximately 25% increase is ...
Koch Lauren G - - 2008
The evolution of biological complexity beyond single-celled organisms was linked temporally with the development of an oxygen atmosphere. Functionally, this linkage can be attributed to oxygen ranking high in both abundance and electronegativity amongst the stable elements of the universe. That is, reduction of oxygen provides for close to the ...
Brethauer Simone - - 2007
Intensified bioprocess development requires parallelized medium- to high-throughput experimentation with high on- and offline data density across all early scales of the development trajectory from microtiter plate via shake flask to lab-scale reactor. We developed a widespread measurement principle for intermediate scales, respirometry, into a parallelized oxygen transfer rate measurement ...
Staffieri Francesco - - 2007
OBJECTIVE: To compare the effect of 2 concentrations of oxygen in inspired gas (fraction of inspired oxygen [FIO(2)] 1.0 or 0.4) on pulmonary aeration and gas exchange in dogs during inhalation anesthesia. ANIMALS: 20 healthy dogs. PROCEDURES: Following administration of acepromazine and morphine, anesthesia was induced in each dog with ...
Kimberger Oliver - - 2007
BACKGROUND: Low tissue oxygen tension is an important factor leading to the development of wound dehiscence and anastomotic leakage after colon surgery. We tested whether supplemental fluid and supplemental oxygen can increase tissue oxygen tension in healthy and injured, perianastomotic, and anastomotic colon in an acutely instrumented pig model of ...
Kamohara Keiji - - 2007
To evaluate the effects of downsizing of the total artificial heart (TAH), we compared the anaerobic threshold (AT) values in calves with two different types of TAH (Cleveland Clinic-Nimbus TAH and the downsized MagScrew TAH). Exercise studies were performed using a treadmill in 12 calves. During the exercise, parameters to ...
Kump Lee R - - 2007
The hypothesis that the establishment of a permanently oxygenated atmosphere at the Archaean-Proterozoic transition (approximately 2.5 billion years ago) occurred when oxygen-producing cyanobacteria evolved is contradicted by biomarker evidence for their presence in rocks 200 million years older. To sustain vanishingly low oxygen levels despite near-modern rates of oxygen production ...
Su Steven W - - 2007
This paper aims to establish a block-structured model to predict oxygen uptake in humans during moderate treadmill exercises. To model the steady state relationship between oxygen uptake (oxygen consumption) and walking speed, six healthy male subjects walked on a motor driven treadmill with constant speed from 2 to 7 km/h. ...
Forrest George P - - 2007
OBJECTIVE: To determine the oxygen consumption of a person with C7 American Spinal Injury Association (ASIA) grade B tetraplegia using the Case Western Reserve/Veterans Administration (CWRU/VA) standing neuroprosthesis. DESIGN: Measure the oxygen consumption and carbon dioxide production of a person with C7 ASIA grade B tetraplegia at rest, standing in ...
Zheng Yuanhui - - 2007
Low-dimensional ZnO nanocrystals with controlled size, aspect ratio, and oxygen defects (e.g., type and concentration) are successfully prepared through simple solvothermal and thermal treatment methods. The structure of the as-synthesized samples is characterized by XRD, N2 physical adsorption, TEM, and IR and XPS spectra. The results show that the aspect ...
Pouilly J-P - - 2008
This study aimed to compare oxygen deficit during exhaustive ramp exercise (OD ramp and OD lag) with maximal oxygen deficit during a high-intensity constant-power test (MAOD). OD ramp was estimated from the difference between oxygen demand and actual oxygen uptake. OD lag was estimated using a simple equation assuming a ...
Vogiatzis I - - 2008
The aim of the present study was to investigate why blood lactate after prolonged quadriceps contraction during hiking is only marginally increased. Eight sailors performed five 3-min hiking bouts interspersed with 5-s recovery periods. Whole body oxygen uptake, heart rate and lactate were recorded, along with continuous-wave near-infrared spectroscopy measures ...
Johannigman Jay - - 2007
Closed loop control of oxygenation and ventilation during mechanical ventilatory support is essential for remote medical care in an austere environment. Closed loop control allows for expert systems to provide the current standard of care in the absence of on-site expertise. Ventilation may be controlled by simple systems incorporating patient ...
Walker Joshua - - 2007
INTRODUCTION: Some degree of recirculation occurs during venovenous extracorporeal membrane oxygenation (VV ECMO) which, (1) reduces oxygen (O2) delivery, and (2) renders venous line oxygen saturation monitoring unreliable as an index of perfusion adequacy. Ultrasound dilution allows clinicians to rapidly monitor and quantify the percent of recirculation that is occurring ...
Kimura Yoshiko - - 2007
To reveal the influence of chronic moderate smoking on physical fitness and local muscle oxygenation profile, we compared the oxygen uptake (VO2), CO2 output, respiratory rate, minute ventilation and blood lactate accumulation between six moderate smokers and ten non-smokers during incremental exercise. In order to know the difference of the ...
Rassaf Tienush - - 2007
Although the primary function of myoglobin (Mb) has been considered to be cellular oxygen storage and supply, recent studies have suggested to classify Mb as a multifunctional allosteric enzyme. In the heart, Mb acts as a potent scavenger of nitric oxide (NO) and contributes to the attenuation of oxidative damage. ...
Remington Nicole - - 2007
Studies of structure-function relationships in the respiratory proteins of marine mammals revealed unexpected variations in the number and types of hemoglobins (Hbs) present in coastal bottlenose dolphins, Tursiops truncatus. We obtained blood samples from free-ranging coastal bottlenose dolphins as a component of capture-release studies. We found that the oxygen-binding functions ...
Taubitz Anela - - 2007
Inhalation of resting conidia is usually the first step of a systemic infection caused by the opportunistic fungal pathogen Aspergillus fumigatus. In the lung, the inhaled spores encounter an environment that permits germination. However, the relative importance of certain environmental conditions for conidial activation and subsequent hyphae formation has so ...
CieĊ›lar Katarzyna - - 2007
Spatial and temporal variations in oxygen partial pressure (pO(2)) during breath-hold can be exploited to obtain important regional parameters of lung function. In the course of apnea, the oxygen concentration is known to decay exponentially. Therefore, the initial pO(2) (p(0)) can be used to represent local ventilation, and the oxygen ...
Maisch Tim - - 2007
New antibacterial strategies are required in view of the increasing resistance of bacteria to antibiotics. One promising technique involves the photodynamic inactivation of bacteria. Upon exposure to light, a photosensitizer in bacteria can generate singlet oxygen, which oxidizes proteins or lipids, leading to bacteria death. To elucidate the oxidative processes ...
Windsor Jeremy S - - 2007
INTRODUCTION: This study examines the effect of supplemental oxygen on acclimatized mountaineers at high altitude during rest and submaximal exercise. METHODS: Three healthy, acclimatized participants undertook nine periods of data collection lasting 10 min each over 2 consecutive days at 5700 m. These occurred at rest and exercise (40 and ...
Ball A J - - 2007
When considering anaesthetic masks, the quality of the mask-face seal is a key determinant of performance. This randomised crossover trial utilises expired oxygen concentration to compare the efficacy of two routinely used facemasks. Thirty subjects were randomised to breathe 100% oxygen via either a traditional reusable black rubber mask or ...
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