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| | Vascular resistance - Wikipedia, the free encyclopedia |
 | | The basic tenet of calculating resistance is that flow is equal to driving pressure divided by resistance. | | | Vascular resistance is a term used to define the resistance to flow that must be overcome to push | | | The resistance offered by the peripheral circulation is known as the |
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http://en.wikipedia.org/wiki/Vascular_resistance
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| | blood pressure |
| | The increase in vascular tone or total peripheral resistance in the obese may be caused by an increase in the alpha?adrenergic response (35), and increased noradrenergic activities (84) or opiate suppression (36). | | | One change is an increase in peripheral vascular resistance, and the second, is a disproportionate increase in systolic blood pressure. | | | However, there is no evidence to support that renal ischemia is the result of age associated changes that are linked with increased peripheral vascular resistance (82). |
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http://www.emunix.emich.edu/~bogle/blood_pressure.htm
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| | Resistance |
| | Resistance to blood flow within a vascular network is determined by the size of individual vessels ( length and diameter), the organization of the vascular network ( series and parallel arrangements), physical characteristics of the blood ( viscosity, laminar flow versus turbulent flow), and extravascular mechanical forces acting upon the vasculature. | | | This is termed "sympathetic vascular tone." Therefore, removal of sympathetic adrenergic influences (for example, by administration of an alpha-adrenoceptor antagonist or by sympathectomy) leads to vasodilation and an increase in organ blood flow. | | | In organs such as the heart and skeletal muscle, mechanical activity (contraction and relaxation) produces compressive forces that can effectively decrease vessel diameters and increase resistance to flow during muscle contraction (see extravascular compression). |
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http://www.oucom.ohiou.edu/cvphysiology/H002.htm
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| | Postoperative |
| | Sympathetic nerve stimulation increases pulmonary vascular resistance, and is responsible for the reflex sympathetic pulmonary vasoconstriction that follows distention of the main pulmonary artery. | | | This latter reflex is particularly strong in the muscularized resistance vessels of the pulmonary circulation of an infant when compared to adults, and may have significant pathophysiological implications in pulmonary hypertensive crises. | | | In the face of increased pulmonary vascular resistance and systemic hypotension, cerebral perfusion pressure may decline to a level that may lead to neurologic ischemia and injury. |
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http://www.pediheart.org/practitioners/principals/postop.htm
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| | © The American Physiological Society - Press Room - For Spinal Cord Injury Patients, New Insights For Rehabilitation ... |
| | The authors of “Increased Vascular Resistance in Paralyzed Legs After Spinal Cord Injury is Reversible by Training,” are Maria T. Hopman, Jan T. Groothuis, Marcel Flendrie, Karin H. Gerrits, and Sibrand Houtman, all from the Department of Physiology, University Medical Centre Nijmegen, The Netherlands. | | | The researchers conclude that leg vascular resistance is dramatically enhanced in SCI individuals. | | | However, no blood pressure data were given in these studies, and, with the knowledge that especially tetraplegic individuals often have low blood pressure levels, it is impossible to speculate about changes in vascular resistance in these SCI individuals. |
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http://www.the-aps.org/press/journal/release1-14-03-4.htm
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| | Reductions in basal limb blood flow and vascular conductance with human ageing: role for augmented alpha-adrenergic ... |
| | First, the absence of significant changes in control limb vascular conductance suggests that the effects of any reflex increases in sympathetic vasoconstrictor nerve activity on femoral artery haemodynamics were minimal. | | | -receptor subtypes to basal leg vascular tone and whether this is affected by ageing could not be determined in the present study. | | | -adrenergic receptors plays no obvious role in the regulation of leg vascular tone in either young or older healthy adults under resting conditions and, therefore, does not appear to be mechanistically involved in the age-related reductions in basal leg blood flow and vascular conductance. |
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http://jp.physoc.org/cgi/content/full/536/3/977
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| | Impaired Microvascular Dilatation and Capillary Rarefaction in Young Adults with a Predisposition to High Blood Pressure |
| | This pattern provides strong evidence against enhanced dermal vascular resistance being a secondary consequence of higher blood pressure, and is consistent with the biologically plausible hypothesis that it is a primary abnormality that contributes to the familial predisposition to high blood pressure. | | | The characteristic increase in peripheral vascular resistance in essential hypertension is, therefore, likely to reflect structural or functional changes in these microvessels. | | | Micropuncture studies show that capillary pressures are elevated in essential hypertension while venous pressure is normal suggesting that capillary or postcapillary vascular resistance is increased. |
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http://www.lawrenz.com/drtlit12.htm
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| | Chronic hypoxia causes angiogenesis in addition to remodelling in the adult rat pulmonary circulation -- Howell et al. ... |
| | Yet the structural changes in the vasculature that we report here may seem, at first sight, to be at variance with the observed increase in pulmonary vascular resistance. | | | These observations demonstrate that the changes in vascular dimensions were greater than could be expected on the basis of distension alone, suggesting that angiogenesis rather than hypertrophy was responsible for the observed hypoxia-induced changes in vessel structure. | | | In such circumstances, the remodelled pulmonary circulation could behave like the normal systemic circulation so that total pulmonary vascular resistance might be dominated by the contribution of constricted arterioles. |
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http://jp.physoc.org/cgi/content/full/547/1/133
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| | Pulmonary Vascular Disease |
| | The purpose of the present study was threefold: to characterize the changes in pulmonary vascular resistance and vascular reactivity induced by hypothermic CPB; to investigate the effects of preexisting increased pulmonary blood flow on these changes; and to better define the role of endothelin 1 in the pathogenesis of post-CPB pulmonary hypertension. | | | CONCLUSIONS: An exaggerated short-term pulmonary vasodilatory response to L-arginine in patients with pulmonary hypertension suggests a relative impairment in pulmonary vascular endothelial NO production that may contribute to increased pulmonary vascular tone and thus be important in the pathophysiology of pulmonary hypertension. | | | CONCLUSIONS: Preexisting increased pulmonary blood flow alters the response of the pulmonary circulation to hypothermic CPB; the increase in pulmonary vascular resistance induced by CPB is augmented in lambs with increased pulmonary blood flow. |
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http://www.pediheart.org/searches/topic/pvod.htm
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| | All-Net ventricular septal defects |
| | When the pulmonary vascular resistance starts to rise and/or the total pulmonic blood flow is greater than twice the systemic flow, the defect will be need to be closed surgically. | | | at certain times a "large" defect (anatomically one equal or greater than the diameter of the aorta) may not have much flow across it if the pulmonary vascular resistance (and right ventricular pressure) is high, as it is just after birth. | | | The primary physiologic variable that determines the physiologic state of the patent is the nature of the pulmonary vascular resistance. |
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http://pedsccm.wustl.edu/All-Net/english/cardpage/operate/vsd/VSD-KUMC.html
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| | British Journal of Pharmacology - Trigeminal nerve ganglion stimulation-induced neurovascular reflexes in the ... |
| | Control changes in mean arterial blood pressure, heart rate and carotid vascular resistance after nerve stimulation were derived from the mean values for the two responses obtained before administration of any drug. | | | In preliminary experiments, a frequency-response relationship was determined for changes in carotid blood flow and vascular resistance. | | | This study is the first to demonstrate that endothelin antagonists, which are effective inhibitors of trigeminal afferent fibre-induced extravasation ( Brandli et al., 1995) also block trigeminal nerve ganglion-induced neurovascular reflex changes in carotid vascular resistance. |
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http://www.nature.com/bjp/journal/v126/n2/full/0702306a.html
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| | PHYSIOLOGY, BLOCK 2: JANUARY 1995 |
| | All of the variables that affect resistance can change, but the only one controlled physiologically is the size of the lumen of the vessel, by contracting or relaxing the smooth muscle in the wall. | | | It is very important to people who have hypertension, and it is very important if a vessel is ruptured and bleeding occurs, but it is largely irrelevant to the flow of blood within the vascular channels. | | | Control of the peripheral resistance gives control of the distribution of blood flow in the body. |
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http://condor.bcm.tmc.edu/MIEC/Syllabi/PhysB2/cardiac06.html
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| | Hemodynamics (pressure, flow, resistance) |
| | Under ideal laminar flow conditions, in which vascular resistance is independent of flow and pressure, this relationship can be depicted as shown in the figure to the right. | | | Changes in resistance are the primary means by which blood flow is regulated within organs because control mechanisms in the body generally maintain arterial and venous blood pressures within a narrow range. | | | The actual blood flow at any given perfusion pressure is determined by the resistance to blood flow. |
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http://www.cvphysiology.com/Hemodynamics/H001.htm
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| | Karolina Kublickiene: Doktorsavhandling från Karolinska Institutet |
| | Owing to the putative involvement of endothelium derived factors in the regulation of vascular tone in uterine circulation, a considerable emphasis was placed on in vitro studies of myometrial resistance arteries which are directly involved in the regulation of uterine blood flow to the placenta during normal pregnancy and PE. | | | The purpose of the studies upon which this thesis is based was to study the effects of endotheium-derived factors, pressure and flow in the modulation of vascular tone in myometrial resistance arteries in normal pregnant women and women with PE. | | | The physiology and pathophysiology underlying the vascular adaptation in human pregnancy is not fully elucidated, and improvement of our knowledge in this field is of the utmost importance. |
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http://diss.kib.ki.se/1997/19971121kubl
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| | INABIS '98 - The Influence Of Arteriolar Growth On Vascular Resistance |
| | Essential hypertension in humans and most animal models of hypertension is characterized by an increased peripheral vascular resistance. | | | The purpose of the present study was to investigate the consequence of various patterns of arteriolar growth on resistance properties of the vascular network. | | | Thus, our study shows that the pattern of early arteriolar growth may have important long-term consequenses for the resistance properties of an arteriolar network. |
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http://www.mcmaster.ca/inabis98/mulvany/struijker-boudier0662
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| | University of Chicago Hospitals: Medical Update: Pulmonary Hypertension |
| | Patients with large pulmonary emboli need to be considered for thrombolytic therapy as an adjunct to heparin. | | | The benefits need to be balanced against the risk of hemorrhage associated with thrombolytic therapy. | | | Several large clinical trials have documented that continuous oxygen therapy will relieve some of the pulmonary vasoconstriction, relieve chronic ischemia throughout the systemic and pulmonary vascular bed, and improve survival. |
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http://www.uchospitals.edu/specialties/heart/services/pulmonary-hypertension/medical-update.html
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| | PERSISTENT PULMONARY HYPERTENSION OF THE NEWBORN |
| | Persistent pulmonary hypertension of the newborn (PPHN) is the result of elevated pulmonary vascular resistance to the point that venous blood is diverted to some degree through fetal channels (i. | | | Persistent pulmonary hypertension of the newborn is a cardiopulmonary disorder characterized by systemic arterial hypoxemia secondary to elevated pulmonary vascular resistance with resultant shunting of pulmonary blood flow to the systemic circulation. | | | At this point, these therapies are experimental and cannot be recommended. |
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http://neonatal.peds.washington.edu/NICU-WEB/pphn.stm
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| | Pediatric Heart Surgery; A Ready Reference for Professionals |
| | These patients exhibit unique cardiovascular physiology in which systemic vascular resistance and pulmonary vascular resistance must be carefully manipulated to achieve a balanced circulation with adequate systemic oxygen delivery. | | | Alterations in ventilation, vasoactive infusions and external stimuli can affect the relative resistances of the systemic and pulmonary circulations. | | | Without intervention, hypoplastic left heart syndrome is uniformly fatal within the first weeks of life. |
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http://members.aol.com/eliotmay2/NorwoodPage.html
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| | The mechanisms underlying altered vascular resistance of glomerular afferent and efferent arterioles in diabetic ... |
| | Correspondence and offprint requests to : Shuji Arima, MD, Division of Nephrology, Endocrinology and Vascular Medicine, Tohoku University School of Medicine, 1–1 Seiryo-cho, Aoba-ku, Sendai 980-8574, Japan. | | | Division of Nephrology, Endocrinology and Vascular Medicine, Tohoku University School of Medicine, Sendai, Japan | | | link between vascular tone and regulation of regional blood |
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http://ndt.oupjournals.org/cgi/content/full/18/10/1966
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| | Test 24 |
| | resistance to the point that venous blood is diverted. | | | (3) This results in vascular relaxation by prohibiting. | | | (1) the balance of vascular resistances shifts so that. |
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http://www.rashaduniversity.com/test24.html
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| | eMedicine - Portal Hypertension : Article Excerpt by: Jesus Carale, MD |
| | This can be applied to vascular flow, ie, P = FR, where P is the pressure gradient through the portal venous system, F is the volume of blood flowing through the system, and R is the resistance to flow. | | | In most types of portal hypertension, both the blood flow and the resistance to blood flow are altered. | | | The initial factor in the pathophysiology of portal hypertension is the increase in vascular resistance to the portal blood flow. |
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http://www.emedicine.com/med/byname/portal-hypertension.htm
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| | MedlinePlus Medical Encyclopedia: Changes in the newborn at birth |
| | Once the cord is cut and the baby takes his first breath, a number of changes occur in the newborn's vascular system. | | | There are some structures in the fetal vascular system that make this type of blood movement possible: | | | There is also an increase in the blood flow resistance of the body's vessels. |
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http://www.nlm.nih.gov/medlineplus/ency/article/002395.htm
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| | THE MERCK MANUAL, Sec. 19, Ch. 261, Congenital Anomalies |
| | No specific therapies for pulmonary vascular disease exist, although research is ongoing for the use of such drugs as prostacyclin. | | | As pulmonary vascular resistance approaches and equals systemic vascular resistance, left-to-right shunting is decreased, and right-to-left shunting leads to systemic desaturation and visible cyanosis. | | | Cautious phlebotomy with maintenance of total blood volume may be beneficial, reducing Hct levels from > 65% to about 60% in a symptomatic patient (eg, one with slurred speech, visual problems, increased fatigue). |
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http://www.merck.com/mrkshared/mmanual/section19/chapter261/261c.jsp
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| | Peripheral vasculur surgery |
| | or peripheral vascular disease pvd is focused on | | | This website has information on peripheral vascular disease symptom related to | | | The place on the world wide web to come when you need new computer hardware, software, peripherals is required for total peripheral resistance We provide them at a low price you would never find elsewhere is required for total peripheral resistance |
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http://innovationpcs.com/SEO/peripheralvasculursurgery.php
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| | Citebase - Low systemic vascular resistance: differential diagnosis and outcome |
| | Melo, Jairo; Peters, Jay I (1999) Low systemic vascular resistance: differential diagnosis and outcome Critical Care 3 71-77 | | | Clinicians should be aware of the wide spectrum of conditions that induce a low SVR. | | | Abstract Objective To determine the frequency and prognosis of the various causes of low systemic vascular resistance (SVR). |
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http://citebase.eprints.org/cgi-bin/citations?id=oai:biomedcentral.com:cc343
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| | Energy Citations Database (ECD) - Energy and Energy-Related Bibliographic Citations |
| | Lovelace Foundation for Medical Education and Research, Albuquerque, NM (USA) | | | Availability information may be found in the Availability, Publisher, Research Organization, Resource Relation and/or Author (affiliation information) fields and/or via the "Full-text Availability" link. | | | Immediate changes in estimated cardiac output and vascular resistance after Co-60 exposure in monkeys. |
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http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=7223061
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| | Vascular Insulin Resistance: The Syndrome X Files |
| | Vascular insulin resistance has been reported to be worsened by dietary salt restriction and improved with ACE-inhibitor therapy. | | | Studies from our laboratory as well as those of others have characterized vascular insulin effects and their alterations in settings of vascular disease/insulin resistance. | | | Further, the selective targeting of some of these mechanisms has been shown to reverse the pattern of endothelial dysfunction characteristic of patients with insulin resistance. |
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http://www.cmeondiabetes.com.au/pub/vascular.insulin.resistance..the.syndrome.x.files.php
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| | Heart Transplantation, Cincinnati Children's Hospital Medical Center |
| | Temporary right ventricular dysfunction may occur secondary to elevations in pulmonary vascular resistance that many recipients may have as a result of longstanding heart failure. | | | Mechanical ventricular support may also be employed to support a patient awaiting transplantation. | | | They may also be on medications to prevent dangerous rhythms from occurring, which are more frequent in failing hearts. |
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http://www.cincinnatichildrens.org/health/info/heart/procedure/transplant.htm
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| | vascular resistance - OneLook Dictionary Search |
| | Phrases that include vascular resistance : systemic vascular resistance, peripheral vascular resistance, peripheral vascular resistance index, pulmonary vascular resistance | | | Resistance, vascular : MedTerms.com Medical Dictionary [ home, info ] | | | vascular resistance, resistance, vascular : The On-line Medical Dictionary [ home, info ] |
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http://www.onelook.com/?w=vascular+resistance&ls=all
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| | Defining resistance in an autoregulating vascular bed |
| | The properties of an autoregulating vascular bed are commonly investigated with two experiments. | | | These phenomena have previously been ascribed to vascular waterfall. | | | From these experiments, investigators have derived peripheral resistance, Rp ( Qin)= Ps / Qin, and instantaneous resistance, Ri ( Qin)= dPi / dQin. |
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http://www.cvm.tamu.edu/cquick/abs/abs2.htm
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| | News - Cortisol Does Not Alter Vascular Resistance |
| | Forearm vascular resistance did not change after the cortisol infusion in either controls or people with hypertension. | | | Short-term cortisol infusions do not alter vascular resistance in either subjects with hypertension nor controls with normal blood pressure. | | | The authors noted, therefore, that alterations in arterio-venous cortisone do not reliably assess 11 beta-hydroxysteroid dehydrogenase activity when cortisone protein binding changes, such as during cortisol infusion. |
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http://www.docguide.com/news/content.nsf/news/8525697700573E1885256CB7000BFA07?OpenDocument&c=&count=10&id=48DDE4A73E09A969852568880078C249
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| | Analysis of the dynamics of renal vascular resistance and urine flow rate in the cat following electrical stimulation ... |
| | Identification of two distinct components in the relaxation phase of renal vascular resistance leads to a reasonable hypothesis that 60% of total renal vascular resistance may lie proximal to the glomerulus, whereas 36% may be accounted for by the efferent arterioles. | | | Subsequent computer processing gave the true means of renal artery pressure (MRAP) and renal blood flow (MRBF) and hence the renal vascular resistance (MRVR), over each cardiac cycle. | | | Analysis of the dynamics of renal vascular resistance and urine flow rate in the cat following electrical stimulation of the renal nerves |
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http://stacks.iop.org/0967-3334/17/213
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| | Vascular Resistance |
| | Vascular Resistance ; Patient Education Handout [Publication Type] ; Hypertension ; | | | This 2 page document has a US focus and is available in PDF, which requires Adobe Acrobat Reader. |
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http://omni.ac.uk/browse/mesh/D014655.html
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| | acid-base indicators on Encyclopedia.com |
| | Using Acid-Base Reagent Problems as a High School Science Research Activity.(student experiment for testing the influence of chlorine on pH indicator) | | | The influence of respiratory acid-base status on adult pulmonary vascular resistance before and after cardiopulmonary bypass. | | | Five rules, and how they simplify complex cases. |
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http://www.encyclopedia.com/html/X/X-acidbase.asp
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| | Physiological Profiling |
| | Slope of the regression for each rat; log dose of NE vs the RVR corresponding to that dose for each of three doses | | | Delta renal vascular resistance from Acetylcholine dose 2 minus pre-Ach control renal vascular resistance | | | Delta renal vascular resistance from AngII dose 1 minus control renal vascular resistance |
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http://pga.mcw.edu/phyprf-bin/showpheno.cgi?chr=all
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| | JULKAISUT / PUBLICATIONS 2004 |
| | Kuusela, T.A., Jartti, T. T., *Tahvanainen, K.U., *Kaila, T.J. 2004: The effects of terbutaline on peripheral vascular resistance and arterial compliance. | | | Kuusela, T. 2004: Stochastic heart-rate model can reveal pathologic cardiac dynamics. |
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http://www.physics.utu.fi/publications2004.html
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| | Prevention Research Center (PRC) - Publications |
| | Davis, M. C., Matthews, K. A., and McGrath, C. Hostile attitudes predict elevated vascular resistance during interpersonal stress in men and women. |
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http://www.asu.edu/clas/asuprc/publications.html
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