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Results 201 - 250 of 1003
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Lai Nicola N Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106-6011, - - 2007
The energy demand imposed by physical exercise on the components of the oxygen transport and utilization system requires a close link between cellular and external respiration in order to maintain ATP homeostasis. Invasive and non-invasive experimental approaches have been used to elucidate mechanisms regulating the balance between oxygen supply and ...
Liguzinski Piotr - - 2007
It has been proposed by Saltin (J Exp Biol 115: 345-354, 1985) that oxygen delivery by blood is limiting for maximal work and oxygen consumption in humans during whole body exercise but not during single-muscle exercise. To test this prediction quantitatively, we developed a static (steady-state) computer model of oxygen ...
Tisdall Martin M - - 2007
The near-IR cytochrome c oxidase (CCO) signal has potential as a clinical marker of changes in mitochondrial oxygen utilization. We examine the CCO signal response to reduced oxygen delivery in the healthy human brain. We induced a reduction in arterial oxygen saturation from baseline levels to 80% in eight healthy ...
Corazza Ivan - - 2007
In clinical practice, oxygen uptake is an indicator of cardiopulmonary performance. Most commercial systems measure oxygen uptake by collecting expired air through masks or mouthpieces which are often poorly tolerated by the patient. We have developed and validated a novel mask-free system to improve patient comfort and performance. The prototype ...
Schober Patrick - - 2007
OBJECTIVE: Carbon monoxide (CO) and oxygen compete for haemoglobin binding sites. While the effects of increased inspiratory oxygen fractions on exhaled carbon monoxide concentrations have been studied previously, the relationships between intravascular oxygen tension, blood carboxyhaemoglobin levels and expiratory CO concentrations remain unclear. We therefore studied the effects of increases ...
McGaw Iain J - - 2007
Exercise and digestive processes are known to elevate the metabolic rate of organisms independently. In this study, the effects of simultaneous exercise and digestion were examined in the graceful crab Cancer gracilis. This species exhibited resting oxygen uptake levels between 29 and 42 mg O(2) kg(-1) h(-1). In postprandial crabs, ...
Jorge R A D L V C - - 2007
The presence of pollutants in the ocean may affect different physiological parameters of animals. Oxygen consumption and ammonia excretion were evaluated in D-shaped larvae of mussels (Perna perna) exposed to zinc sulphate (ZnSO(4)) and benzene (C(6)H(6)). When compared to the control group, both pollutants presented a significant reduction in oxygen ...
Li Jia - - 2007
OBJECTIVES: The lack of accurate measurement of hemodynamics and oxygen transport has limited our understanding of Norwood physiology and postoperative management. We used measured oxygen consumption to characterize hemodynamics and oxygen transport after the classic Norwood procedure. METHODS: Fourteen neonates had continuous respiratory mass spectrometry to measure oxygen consumption (VO2). ...
Lobo Susana A L - - 2007
Sulfate reducing bacteria of the Desulfovibrio genus are considered anaerobes, in spite of the fact that they are frequently isolated close to oxic habitats. However, until now, growth in the presence of high concentrations of oxygen was not reported for members of this genus. This work shows for the first ...
Dascombe, Benjamin James
This thesis details four consecutive research investigations which were designed to examine the effect of age on the pulmonary oxygen uptake (VO2)and muscle oxygenation (mOxy) responses to exercise in well-trained cyclists. (Abridged)
Ramos Raddy L - - 2007
The principles of neurophysiology continue to be challenging topics to teach in the context of undergraduate neuroscience education. Laboratory classes containing neurophysiological demonstrations and exercises are, therefore, an important and necessary complement for covering those subjects taught in lecture-based courses. We developed a number of simple yet very instructive exercises, ...
Pereira Marta I R - - 2007
There is growing interest in resistance training, but many aspects related to this type of exercise are still not fully understood. Performance varies substantially depending on how resistance training variables are manipulated. Fatigue is a complex phenomenon usually attributed to central (neuronal) and/or peripheral (muscular) origin. Cerebral oxygenation may be ...
Iyer Rohin K - - 2007
The prominence of cardiovascular diseases has prompted investigations into alternative treatment options, including tissue engineering. Currently, the biggest limitation in cardiac tissue engineering lies in delivering oxygen to all cells within the construct. Synthetic oxygen carriers hold much promise in that they have high affinity for oxygen and can be ...
Khurana Rahul N - - 2007
PURPOSE: We describe a novel method to oxygenate intraocular irrigation solutions involving an in-line oxygenator. METHODS: Either lactated Ringer (LR) solution or balanced salt solution (BSS) was oxygenated with the FE390 Stainless In-line Oxygenation Assembly (Beer, Beer, and More Beer, Concord, CA). After running a 100-mL of solution through the ...
Nieman David C - - 2007
The purpose of this study was to assess the validity of the FitMate metabolic system (Cosmed, Rome, Italy) in measuring oxygen consumption during graded exercise. The FitMate is a new, small (20 x 24 cm) metabolic analyzer designed for measurement of oxygen consumption during rest and exercise. Subjects included 40 ...
Wold J P - - 2006
In this study, fluorescence excitation and emission matrices and multivariate curve resolution (PARAFAC) were used to detect and characterize active photosensitizers spectrally in butter. Butter samples were packed under high (air) and low oxygen (<0.05%) atmospheres and exposed to violet, green, or red light. Six photosensitizers were found: riboflavin, protoporphyrin, ...
Uemura Ryuichiro - - 2007
BACKGROUND: Recently, hepatic surgery has made remarkable progress, and it is important to use appropriate liver perfusion. We evaluated the effect of normothermic liver perfusion with the addition of fructose-1, 6-bisphosphate (FBP) and oxygenation to maintain liver parenchymal, non-parenchymal, and Kupffer cell function. MATERIALS AND METHODS: The rats were divided ...
Fink Barbara - - 2006
Factors that influence the polarographic measurement of the oxygen uptake of the cornea are reviewed. These factors include the technique, electrode assembly, oxygen reservoir, membrane material and thickness, oxygen tension of the corneal environment, duration of exposure to environmental conditions and time to application of the probe all influencing measured ...
Ashenden M J - - 2007
Haemoglobin-based oxygen carriers (HBOCs) such as Hemopure are touted as a tenable substitute for red blood cells and therefore potential doping agents, although the mechanisms of oxygen transport of HBOCs are incompletely understood. We investigated whether infusion of Hemopure increased maximal oxygen uptake (V.O 2max) and endurance performance in healthy ...
Sharma S K - - 2006
Tuberculosis (TB) is a major health problem in the developing world. In this preliminary study, we report the effect of antituberculosis treatment (ATT) on cardiopulmonary responses to exercise in patients with miliary tuberculosis (MTB). The prospective study of cardiopulmonary responses to exercise in patients with MTB within one month of ...
Sternberg Leonel - - 2006
The oxygen isotopic composition of plant cellulose is commonly used for the interpretations of climate, ecophysiology and dendrochronology in both modern and palaeoenvironments. Further applications of this analytical tool depends on our in-depth knowledge of the isotopic fractionations associated with the biochemical pathways leading to cellulose. Here, we test two ...
Hotta Norio - - 2006
The purpose of the present study was to examine the effect of unilateral lower limb suspension (ULLS) deconditioning on oxygen uptake kinetics. Eight healthy males underwent ULLS for 20 days and performed a series of 6-min square-wave transitions from rest to 60-W single-leg cycling exercises just before and after ULLS. ...
Masci Bernardo - - 2006
In the acetylation of an oxygenated calix[4]arene homologue in the presence of CsF as a base, relaxation of the reaction system to the equilibrium composition takes place through several intra- and intermolecular steps that can be easily controlled to obtain the various acetyl derivatives. The effect of different bases is ...
de Geus Bas - - 2006
The objectives of this study were to (1) continuously assess oxygen uptake and heart rate; (2) quantify the extent to which maximal whole-body cardiorespiratory capacity is utilized during climbing on four routes with the same difficulty but different steepness and/or displacement. Fifteen expert climbers underwent a maximal graded exercise test ...
Ottosen Lars D M - - 2006
Understanding the biology of reproductive organs is essential for the development of assisted reproductive techniques. There is at present no direct evidence for either the concentration and dynamics of intrauterine oxygen tension at the endometrial surface, nor its importance for the receptiveness of the endometrium. In this study a new ...
Nowak-Sliwinska Patrycja - - 2006
The efficiency of photodynamic effect (PDE) for Photofrin II (PfII), Verteporfin, and Merocyanine 540 (MC540) was compared against neoplastic cells. Triplet state lifetimes and singlet molecular oxygen quantum yields were correlated with biological effect. PfII triplet lifetime was two times longer than that of Verteporfin, however, its singlet molecular oxygen ...
Saito Takeshi - - 2006
A quantitative analysis of the oxygen concentration profile near a poly(dimethylsiloxane) (PDMS) microfluidic device was performed using scanning electrochemical microscopy (SECM). A microchannel filled with sodium sulfite (Na(2)SO(3)) aqueous solution was imaged by SECM, showing that the oxygen diffusion layer of the PDMS microchannel was observed to be hemicylindrical. Based ...
Thomas Matthew J - - 2006
Rising concerns over respiratory illnesses caused by agents such as avian influenza viruses and SARS coronavirus have prompted intensive research efforts and the resurgence of nonhuman primates as models for these human diseases. In the context of studying influenza infection and vaccine development, serial bronchoscopic procedures, including bronchial brush biopsies ...
Patel Mayur B - - 2006
BACKGROUND: Data are limited on the actions of hemoglobin based oxygen carriers (HBOCs) after traumatic brain injury (TBI). This study evaluates neurotoxicity, vasoactivity, cardiac toxicity, and inflammatory activity of HBOC-201 (Biopure, Cambridge, Mass.) resuscitation in a TBI model. METHODS: Swine received TBI and hemorrhage. After 30 minutes, resuscitation was initiated ...
Mathru Mali - - 2006
BACKGROUND: In conscious humans, reduction in hemoglobin concentration to 5 g/dl did not produce inadequate systemic oxygenation. However, systemic measures of inadequate oxygenation may not be sufficiently sensitive to detect inadequate oxygenation in individual organs such as splanchnic organs. The authors tested the hypothesis that acute normovolemic anemia to hemoglobin ...
Russell John A JA William S. Middleton Memorial Veterans Hospital and the Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin, Madison, - - 2006
Venous outflow obstruction is the most common cause of tissue failure after microvascular reconstructive surgery. If it is not recognized early, there is an increased risk of tissue damage and loss. Currently, however, there are no adequate models for the study of this clinical problem. The purpose of this study ...
Shibata Masahiro - - 2006
We tested the hypothesis that oxygen is supplied to the resting skeletal muscle by arterioles rather than by capillaries. This hypothesis was evaluated in rats and rabbits by combining different approaches (1) determination of the intravascular oxygen tension (PO2) in arterioles of different diameters, (2) measurement of the perfused capillary ...
Kidder George W GW - - 2006
We have developed a flow-through method for measuring oxygen consumption in fish which allows continuous monitoring over periods of days with good accuracy. Our goal was to determine the changes in basal metabolic rate in estuarine fish as a function of salinity. We show that in Fundulus heteroclitus, the oxygen ...
Richmond Julie P - - 2006
Two key factors influence the diving and hence foraging ability of marine mammals: increased oxygen stores prolong aerobic metabolism and decreased metabolism slows rate of fuel consumption. In young animals, foraging ability may be physiologically limited due to low total body oxygen stores and high mass specific metabolic rates. To ...
Yu Dao-Yi - - 2006
PURPOSE: To make the first measurements of intraretinal oxygen distribution in the mouse, an animal model of increasing importance in ophthalmic research. METHODS: Oxygen-sensitive microelectrodes were used to measure oxygen tension as a function of depth through the retina and choroid in anesthetized mice (n = 8). All measurements were ...
Futrell James W JW - - 2006
Facemasks and nasal cannulae are used to provide supplemental oxygen to patients in the postoperative period after general anesthesia. These devices are associated with several patient complications, including aspiration, hypercarbia, and mechanical trauma. A new device, the OxyArm, is designed to eliminate these problems. It is an "open oxygen" system ...
Mimura, Tatsuya
MIMURA, T., TANAKA, S., ISHIHARA, K., WADAZUMI, T., MIYAMOTO, T., FUJIWARA, H. and FUJIMOTO, S., Relationships Among Muscle Oxygenation, Blood Lactate Concentration, and Substrate Utilization During Prolonged Exercise Below Anaerobic Threshold. Abv. Exerc. Sports Physiol., Vol.9, No.4 pp.111-117, 2003. The purpose of this study was to examine the relationships among ...
Kawahara, Yayoi
KAWAHARA, Y., MIZUNO, M., IWAKAWA, T., NAKAMURA, Y. and MURAOKA, I. Relationship Between Oxygen Supply and Consumption in Exercised Muscle During Recovery. Adv. Exerc. Sports Physiol., Vol.11, No.2 pp55-60, 2005. The purposes of this study were to measure muscle oxygenation kinetics and the oxygen consumption index (OCI) and the oxygen ...
Braun Jan-Peter - - 2006
Normothermic, nonpulsatile cardiopulmonary bypass (CPB) impairs systemic and splanchnic oxygen transport and increases gastrointestinal permeability. It is an important therapeutic goal to avoid splanchnic dysoxia during CPB. Small-dose prostacyclin therapy improves splanchnic oxygen transport and microcirculation in septic patients. In this study, we sought to determine if during cardiac surgery, ...
Rollins M D - - 2006
Hyperbaric oxygen (HBO2) increases wound oxygen delivery, but few data quantify wound oxygen levels over the course of healing. We characterized these changes during and after HBO2 treatment in a rat wound model. The treatment group (n=7) received 2.0 ATA HBO2, 90 minutes BID for 15 days. Control rats (n=5) ...
Collins Aaron M - - 2006
A patient with severe hypothermia presented with an initial rectal temperature of 28.3 degrees C coupled with a hemoglobin of 2.2 g x dL(-1) and acute pancreatitis. Although hypothermia decreases oxygen and substrate consumption by tissues and can be cerebro-protective, the ideal rewarming strategy is unclear when the oxygen-delivery system ...
Su Steven W SW Human Performance Group, New South Wales Univ., Sydney, NSW, Australia. - - 2006
This paper aims to establish block-structured nonlinear model (Hammerstein model) to predict oxygen uptake during moderate treadmill exercises. In order to model the steady state relationship between oxygen uptake (oxygen consumption) and walking speed, six healthy male subjects walked on a motor driven treadmill at six different speed (2,3,4,5,6, and ...
Acker Helmut - - 2005
Structural and functional integrity of organ function profoundly depends on a regular oxygen and glucose supply. Any disturbance of this supply becomes life threatening and may result in severe loss of organ function. Particular reductions in oxygen availability (hypoxia) caused by respiratory or blood circulation irregularities cannot be tolerated for ...
Pareek Mamta - - 2006
Armillaria luteobubalina produces air pores in culture. They consist of two parts: a basal region of tissue elevated to form a mound covered with a rind continuous with that of the colony, but perforated; and an apical region of long parallel hyphae, cemented together by scattered patches of extracellular material. ...
Williams D L - - 2006
Cystic lesions in the eyes of farmed halibut with a number of ocular sequelae have been reported previously with evidence that the condition can be associated with increased activity of choroidal carbonic anhydrase and elevated oxygen tension in the aqueous humour of affected fish. These changes may be compared to ...
Freitag Marc - - 2005
PURPOSE: While the effects of dilutional anemia or isovolemic hemodilution (IHD) on the oxygen extraction and tissue oxygenation in peripheral organs after application of hemoglobin-based oxygen carriers like HBOC-201 have been studied intensively, little is known about tissue oxygenation properties of hemoglobin solutions in central organs like the liver. METHODS: ...
Zhu Zhiwen - - 2005
STUDY OBJECTIVE: The purpose of this study was to determine if an oxygen prescription based on continuous oximetry monitoring, would result in an increased percentage of time spent within an SpO2 level between 88% and 92%. METHODS: We conducted a prospective, cohort study in an outpatient, pulmonary setting in a ...
Schears Gregory G Mayo Clinic, Rochester, and Department of Biochemistry and Biophysics, The University of Pennsylvania, Philadelphia 19104, - - 2005
The oxygen distribution in the microcirculation of the piglet's brain and striatal extracellular dopamine were determined during repetitive apnea and resuscitation with 21% or 100% oxygen. Pre-apnea cortical oxygen was 49.5+/-10.4 mm Hg and during each apnea decreased to 8+/-0.9 mm Hg. After ten apneic episodes followed by resuscitation with ...
Rahardjo Yovita S P - - 2005
In this paper, the effects of bed porosity, bran and specific surface area on the oxygen uptake rate and alpha-amylase production during growth of Aspergillus oryzae on wheat grain and wheat-flour substrate are reported. The high oxygen uptake rate found during cultivation of A. oryzae on wheat-flour substrate was not ...
Lopes Paulo - - 2005
Oxygen is one of the most important factors determining the aging potential of bottled wine, and oxygen diffusion into bottled wine is extremely dependent on the sealing effectiveness of the closure. A nondestructive colorimetric method was developed to measure oxygen diffusion from 1 to 9.8 mg/L during the postbottling period. ...
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