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  • perfusion
  • Despite a decrease in coronary perfusion pressure, coronary blood flow is increased. (ahajournals.org)
  • Both octanoic acid and oleic acid stimulated oxygen consumption to a similar degree during hypothermic perfusion suggesting that the detrimental effect of octanoic acid was due to direct metabolic stimulation rather than uncoupling of oxidatative phosphorylation. (wikipedia.org)
  • However, in altered cardiac function, such as hypoperfusion caused by hypotension, heart attack or cardiac arrest caused by nonperfusing bradycardias, adenosine has a negative effect on physiological functioning by preventing necessary compensatory increases in heart rate and blood pressure that attempt to maintain cerebral perfusion. (wikipedia.org)
  • Magnetic resonance imaging can estimate the size of the penumbra with a combination of two MRI sequences: Perfusion weighted imaging (PWI) shows decreased blood perfusion in the infarcted core and the penumbra Diffusion weighted imaging (DWI) can estimate the size of the infarcted core. (wikipedia.org)
  • metabolism
  • These results indicate that ( i ) the energy demand of task-induced brain activation is small (approximately 15%) relative to the hyperemic response (approximately 60%), ( ii ) this energy demand is met through oxidative metabolism, and ( iii ) the CBF response is mediated by factors other than oxygen demand. (pnas.org)
  • Fox and colleagues suggested that ( i ) the energy demand associated with neuronal activation (as opposed to resting-state demand) is small (approximately 8% maximum possible increase in ATP consumption), ( ii ) the activation-induced increases in ATP consumption are from both oxidative and nonoxidative glycolysis, and ( iii ) CBF response must be regulated by factors other than oxidative metabolism and total energy demand. (pnas.org)
  • GABA brain metabolism and GABA receptors are not affected by piracetam It has been found to increase blood flow and oxygen consumption in parts of the brain, but this may be a side effect of increased brain activity rather than a primary effect or mechanism of action for the drug. (wikipedia.org)
  • It has been found to increase oxygen consumption in the brain, apparently in connection to ATP metabolism, and increases the activity of adenylate kinase in rat brains. (wikipedia.org)
  • Metabolic regulation is driven by the between cerebral metabolism (demand) and oxygen delivery through cerebral blood flow (supply) and acts by means of a vasoactive substance. (wikipedia.org)
  • pulmonary blood
  • There appears to be a connection between pulmonary edema and increased pulmonary blood flow and pressure which results in capillary engorgement. (wikipedia.org)
  • Correction of spillover from pulmonary gas volume requires correction of the lung time-activity curve for pulmonary blood volume, which could equally well be obtained from a O-15-water rather than (CO)-O-15 scan. (diva-portal.org)
  • venous blood
  • 1 ) the central (autonomic) command that accompanies active muscle contraction and 2 ) the displacement of large amounts of venous blood to the right atrium by the massive muscle action induced by active standing, eliciting a cardiopulmonary (CP) reflex effect on the systemic circulation. (physiology.org)
  • The venous blood is drained via superior and middle thyroid veins, which drain to the internal jugular vein, and via the inferior thyroid veins. (wikipedia.org)
  • reduction
  • 2. The term shallow water blackout has also been used in the scientific literature over many years to refer to loss of consciousness caused by cerebral hypoxia at the end of a deep breath-hold dive during the latter part of the ascent or immediately after surfacing due to lowered oxygen partial pressure caused by reduction in ambient pressure. (wikipedia.org)
  • Since in quiet waking the brain is responsible for 20% of the body's energy use, this reduction has an independently noticeable impact on overall energy consumption. (wikipedia.org)
  • systolic
  • Low blood pressure patients, with systolic blood pressures below 90 mm Hg, should not be treated with diltiazem. (wikipedia.org)
  • Evoked blood pressure changes can be the result of: releasing leg cuffs that were inflated above systolic pressure breathing at a fixed rate performing a Valsalva maneuver performing squat-stand or sit-stand maneuvers lower body negative pressure pharmaceutical methods to raise or lower blood pressure The quantification depends on the experimental setup and can involve methods such as regression, cross-correlation, transfer function analysis or fitting mathematical models. (wikipedia.org)
  • systemic
  • In a previous study we demonstrated that in lambs with an aortopulmonary left to right shunt, isoproterenol increased systemic blood flow more than dopamine did, because isoproterenol increased heart rate . (onlinejacc.org)
  • Pressures
  • He used diluted plasma or serum as the perfusate and pointed out the necessity for low perfusate pressures to prevent kidney swelling, but admitted that the optimum values for such variables as perfusate temperature, Po2, and flow, remained unknown. (wikipedia.org)
  • humans
  • Dawson EA, Secher NH, Dalsgaard MK, Ogoh S, Yoshiga CC, Gonzalez-Alonso J, Steensberg A, Raven PB (2004) Standing up to the challenge of standing: a siphon does not support cerebral blood flow in humans. (springer.com)
  • pressure
  • Studies using preimaging radiotracer techniques demonstrated that brain blood flow can be markedly elevated by increased partial pressure of CO 2 and by decreased partial pressure of O 2 , a form of cerebrovascular autoregulation ( 2 ). (pnas.org)
  • Experiments were done in the isolated supported heart preparation to ascertain whether a change in coronary blood flow would induce a change in myocardial O 2 consumption if the activity of the heart (aortic pressure, heart rate and stroke volume) was controlled. (ahajournals.org)
  • The steady-state response to active standing and HUT is usually comparable, but there is a difference in the blood pressure (BP) and heart rate (HR) responses in the first 30 s ( Fig. 1 ). (physiology.org)
  • Blood pressure and heart rate responses to passive head-up tilt (HUT) and active standing. (physiology.org)
  • Bowie RA, O'Connor PJ, Hardman JG, Mahajan RP (2001) The effect of continuous positive airway pressure on cerebral blood flow velocity in awake volunteers. (springer.com)
  • Droste DW, Ludemann P, Anders F, Kemeny V, Thomas M, Krauss JK, Ringelstein EB (1999) Middle cerebral artery blood flow velocity, end-tidal pCO 2 and blood pressure in patients with obstructive sleep apnea and in healthy subjects during continuous positive airway pressure breathing. (springer.com)
  • Immersion of the human body in water has effects on the circulation, renal system and fluid balance, and breathing, which are caused by the external hydrostatic pressure of the water providing support against the internal hydrostatic pressure of the blood. (wikipedia.org)
  • Hydrostatic pressure on the body due to head out immersion causes negative pressure breathing which contributes to the blood shift. (wikipedia.org)
  • Common side effects include an irregular heart rate, low blood pressure, burning sensation at the site of injection, and the stopping of breathing. (wikipedia.org)
  • It relaxes the smooth muscles in the walls of arteries, which opens (dilates) the arteries, allows blood to flow more easily, and lowers blood pressure. (wikipedia.org)
  • Additionally, it lowers blood pressure by acting on the heart itself to reduce the rate, strength, and conduction speed of each beat. (wikipedia.org)
  • These effects also reduce blood pressure by causing less blood to be pumped out. (wikipedia.org)
  • A reflex sympathetic response, caused by the peripheral dilation of vessels and the resulting drop in blood pressure, works to counteract the negative inotropic, chronotropic and dromotropic effects of diltiazem. (wikipedia.org)
  • The mechanism of deep water blackout is hypoxia, arising from the rapid drop in the partial pressure of oxygen in the lungs on ascent as the ambient pressure drops and the gas in the lungs expands to surface volume. (wikipedia.org)
  • Latent hypoxia This describes the precursor to blackout on ascent where the partial pressure of oxygen remains sufficient to maintain consciousness, but only at depth, under pressure, and is already insufficient to maintain consciousness at the shallower depths that must be encountered on ascent. (wikipedia.org)
  • 3. Also used in diving but not in free diving, loss of consciousness while ascending on a rebreather due to sudden drop of oxygen partial pressure in the breathing loop, usually associated with manual CCR and SCR. (wikipedia.org)
  • In pooled data, from three comparative studies conducted in 200 patients with mild to moderate hypertension, 2.5 mg of levamlodipine was found to be equivalent in its blood pressure lowing efficacy to 5 mg of amlodipine. (wikipedia.org)
  • The quantification of cerebral autoregulation always involves variation seen in cerebral blood flow in relation to changes in blood pressure. (wikipedia.org)
  • This blood pressure variation can either be evoked or spontaneous. (wikipedia.org)
  • brain tissue
  • The third decade of penumbral research found a transitional leap as using positron emission tomography (PET) scanning can identify brain tissue with decreased blood flow and magnetic resonance imaging (MRI) has the ability to detect portions of the ischemic tissue that has not yet died. (wikipedia.org)
  • tissue
  • Using an epigastric pouching technique, it is possible to obtain a tissue-isolated preparation which makes direct studies of blood flow and oxygen supply in human tumors feasible. (aacrjournals.org)
  • Due to marked intra- and intertumor variabilities in blood flow, heterogeneities in the tissue oxygenation are characteristic features of human breast cancer xenografts. (aacrjournals.org)
  • From the results obtained it is concluded that human breast cancers growing as xenografts in rnu/rnu rats may be useful tools for cancer research, especially for investigations of blood flow, tissue oxygenation, and substrate turnover. (aacrjournals.org)
  • Blood flow and oxygen extraction fraction (OEF) were calculated from dynamic PET scans at the location of BAT, muscle, and white adipose tissue. (pubmedcentralcanada.ca)
  • Blood flow values were significantly higher in the high-BAT group than in the low-BAT group for BAT (12.9 ± 4.1 vs. 5.9 ± 2.2 mL/100 g/min, P = 0.03) and white adipose tissue (7.2 ± 3.4 vs. 5.7 ± 2.3 mL/100 g/min, P = 0.03) but were similar for muscle (4.4 ± 1.9 vs. 3.9 ± 1.7 mL/100 g/min). (pubmedcentralcanada.ca)
  • The method of analysis was optimized by investigating potential reuse of myocardial blood flow (MBF), perfusable tissue fraction, and blood and lung spillover factors derived from separate O-15-water and (CO)-O-15 scans. (diva-portal.org)
  • The optimal accuracy and precision of OEF were obtained when fixing MBF, perfusable tissue fraction, and blood spillover to values derived from a O-15-water scan and estimating spillover from the pulmonary gas volume using an attenuation map. (diva-portal.org)
  • Circulation
  • a modeling approach to the study of the blood circulation and its response to postural changes can provide insight into the underlying physiology. (physiology.org)
  • velocity
  • To determine the body position least affecting indices of CBF and CBV, the middle cerebral artery mean blood velocity (MCA V mean ) and the near-infrared spectroscopy determined frontal cerebral hemoglobin content (cHbT) were evaluated in 11 healthy subjects during CPAP at different body positions (15° head-down tilt, supine, 15°, 30° and 45° upper body elevation). (springer.com)
  • Giller CA (1989) Transcranial Doppler monitoring of cerebral blood velocity during craniotomy. (springer.com)
  • blackout
  • Breath-hold duration is limited by oxygen reserves, and the risk of hypoxic blackout, which has a high associated risk of drowning. (wikipedia.org)
  • heart
  • CPAP impairs venous return to the heart and, in turn, affects cerebral blood flow (CBF) and augments cerebral blood volume (CBV). (springer.com)
  • the heart has to work harder to pump the same volume of blood throughout the body, and for people with heart disease, this additional workload can cause the heart to go into arrest. (wikipedia.org)
  • It optimizes respiration by preferentially distributing oxygen stores to the heart and brain which allows staying underwater for extended periods of time. (wikipedia.org)
  • Diltiazem is a potent vasodilator, increasing blood flow and variably decreasing the heart rate via strong depression of A-V node conduction. (wikipedia.org)
  • Each of these effects results in reduced oxygen consumption by the heart, reducing angina symptoms. (wikipedia.org)
  • energy
  • The Roy-Sherrington principle has been interpreted to mean that blood flow changes must be a function of a tight coupling between cellular energy requirements and the supplies of glucose and oxygen. (pnas.org)
  • results
  • However, because no information was obtained about how these catecholamines would affect myocardial oxygen consumption (V̇ o 2 ), blood flow distribution and total body V̇ o 2 , the results of that study were not conclusive with regard to using any of these catecholamines at an early age. (onlinejacc.org)
  • muscles
  • However, the ability to perform useful work like staying afloat declines substantially after ten minutes as the body protectively cuts off blood flow to "non-essential" muscles. (wikipedia.org)
  • cellular
  • Human breast cancer xenografts in T-cell-deficient rnu/rnu rats permit the detailed and systematic study of blood flow, oxygen supply, and characterization of the cellular microenvironment of human tumors in vivo . (aacrjournals.org)
  • Losses
  • This causes a blood shift from the extravascular tissues of the limbs into the chest cavity, and fluid losses known as immersion diuresis compensate for the blood shift in hydrated subjects soon after immersion. (wikipedia.org)
  • rate
  • At comparable tumor sizes, the average blood flow rate through human breast cancer xenografts is higher in medullary than in squamous cell carcinomas (0.17 versus 0.10 ml·g -1 ·min -1 ). (aacrjournals.org)
  • study
  • The aim of this study was to determine the accuracy of oxygen extraction fraction (OEF) measurements using a dynamic scan protocol after bolus inhalation of O-15(2). (diva-portal.org)
  • changes in blood
  • This resting brain activity is observed through changes in blood flow in the brain which creates what is referred to as a blood-oxygen-level dependent (BOLD) signal that can be measured using functional magnetic resonance imaging (fMRI). (wikipedia.org)
  • Functional magnetic resonance imaging (functional MRI or fMRI) is a specific magnetic resonance imaging (MRI) procedure that measures brain activity by detecting associated changes in blood flow. (wikipedia.org)
  • body
  • Prior to this, kidneys had been stored at normal body temperatures using blood or diluted blood perfusates, but no successful reimplantations had been made. (wikipedia.org)
  • atoms
  • A dehydrating agent, such as concentrated sulfuric acid is typically added: B(OH)3 + 3 ROH → B(OR)3 +3 H2O The three oxygen atoms form a trigonal planar geometry around the boron. (wikipedia.org)
  • vessels
  • Congenital heart disease, also abbreviated to CHD and not to be confused with coronary heart disease, is a type of defect or malformation in one or more structures of the heart or blood vessels that occurs before birth. (blogspot.com)
  • medical citation needed] Extreme blood pressure can lead to problems in the eye, such as retinopathy or damage to the blood vessels in the eye. (wikipedia.org)
  • acute
  • It is a widely explored treatment option for many central nervous system (CNS) disorders including neurodegenerative diseases, stroke, traumatic brain injury, spinal cord injury, and acute management of neurotoxin consumption (i.e. methamphetamine overdoses). (wikipedia.org)
  • A hypertensive emergency, also known as malignant hypertension, is high blood pressure with potentially life-threatening symptoms and signs indicative of acute impairment of one or more organ systems (especially the central nervous system, cardiovascular system or the kidneys). (wikipedia.org)
  • The kidneys will be affected, resulting in blood and/or protein in the urine, and acute kidney failure. (wikipedia.org)
  • pressure
  • SC-Y200 ventilator can work with some innovative ventilation modes, e.g., constant flow mode, pressure limit mode and time cycle ventilation mode, and also supports PEEP and IMV functions. (cima-medical.com)
  • This may not be a big problem in the beginning as the left chambers which have a higher pressure system than the right will direct blood to the right chambers via the hole or defect in the wall. (blogspot.com)
  • Most genes belong of various exons and introns 10mg prinivil overnight delivery blood pressure 20090 . (4hbtalk.com)
  • citation needed] The gas is not flammable at a low pressure/temperature, but it delivers more oxygen than atmospheric air by breaking down at elevated temperatures. (wikipedia.org)
  • Typically the systolic blood pressure is at least over 180 mmHg or the diastolic is over 110-120 mmHg. (wikipedia.org)
  • In a hypertensive emergency, the blood pressure should be slowly lowered over a period of minutes to hours with an antihypertensive agent. (wikipedia.org)
  • The former use of oral nifedipine, a calcium channel blocker, has been strongly discouraged as it has led to excessive falls in blood pressure with serious and fatal consequences. (wikipedia.org)
  • Sometimes, the term hypertensive emergency is also used as a generic term, comprising both hypertensive emergency, as a specific term for a serious and urgent condition of elevated blood pressure, and hypertensive urgency, as a specific term of a less serious and less urgent condition (the terminology hypertensive crisis is usually used in this sense). (wikipedia.org)
  • The term hypertensive emergency is primarily used as a specific term for a hypertensive crisis with a diastolic blood pressure greater than or equal to 120 mmHg or systolic blood pressure greater than or equal to 180 mmHg. (wikipedia.org)
  • During a hypertensive emergency uncontrolled blood pressure leads to progressive or impending end-organ dysfunction. (wikipedia.org)
  • Therefore, it is important to lower the blood pressure aggressively. (wikipedia.org)
  • alcohol
  • They include genetic or chromosomal abnormalities in the child such as Down's Syndrome, viral infections in the mother during pregnancy such Rubella, and consumption of certain drugs or alcohol by the mother during pregnancy. (blogspot.com)
  • body
  • It opens and cleanses the liver, helps the jaundice, and is very beneficial to the bowels, healing all inward wounds, bruises, hurts and other distempers…The liver is the former of the blood, and blood the nourisher of the body, and Agrimony a strengthener of the liver. (yorkshireherbalist.co.uk)
  • The Oxyhemoglobin Dissociation curve shows how blood carries oxygen through the body. (blogspot.com)
  • That as the body attempts to compensate for low iron levels by increasing red blood cell production in the young, sieve-like lesions develop in the cranial vaults (termed porotic hyperostosis) and/or the orbits (termed cribia orbitalia). (wikipedia.org)
  • levels
  • The complications are hepatic encephalopathy and impaired protein synthesis (as measured by the levels of serum albumin and the prothrombin time in the blood). (wikipedia.org)
  • less
  • With the feature of innovative functions, convenient operation, less gas consumption, compact but reasonable structure, and outstanding safety and reliability, it is an indispensable instrument in emergency and ICU rooms, and an essential tool to rescue the life of infants and children. (cima-medical.com)
  • Marcus Raichle Experiments by neurologist Marcus E. Raichle's lab at Washington University School of Medicine and other groups showed that the brain's energy consumption is increased by less than 5% of its baseline energy consumption while performing a focused mental task. (wikipedia.org)
  • important
  • In the gills, there are neuroepithelial cells, which are important for sensing oxygen during developmental and adult stages. (wikipedia.org)
  • damage
  • These injuries can cause inflammation that reduces the blood supply to the testicles, which can permanently damage sperm-producing cells. (grandstrandmed.com)
  • Course
  • This supposedly had something to do with changing the acidity of your blood, but of course when prompted this person couldn't supply any actual physiological mechanism to explain this effect. (blogspot.com)
  • least
  • 12. The process of claim 1, wherein the culturing of the strain of the family Streptococcaceae is carried out under aeration, e.g. the culture is aerated so as to maintain an oxygen content which is at least 2 micromoles per liter of culture medium. (patentsencyclopedia.com)
  • together
  • Any breach in the wall will mean that blood with different oxygen concentrations are mixed together. (blogspot.com)
  • Together they also developed a complex solution for studying blood flow in arteries or perfusion ex vivo called Krebs-Henseleit solution or buffer. (wikipedia.org)