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| | Capilary Fluid_Exchange |
 | | Changes in arterial pressure per se may have little effect on filtration, since the change in pressure may be countered by adjustments of the precapillary resistance vessels so that hydrostatic pressure in the open capillaries remains the same. | | | The relationship between hydrostatic pressure and oncotic pressure and the role of these forces in regulating fluid passage across the capillary endothelium were expounded by Starling in 1896 and constitute the Starling hypothesis. | | | An increase in venous pressure alone, as occurs in the feet when one changes from the lying to the standing position, would elevate capillary pressure and enhance filtration. |
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http://omaha.physiol.arizona.edu/Physiology485/Gore/Lecture21a/Gore.L21a.html
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| | Fluid Physiology: 4.4 Pulmonary Microcirculation |
| | The interstitial hydrostatic pressure probably becomes more negative as the hilum is approached. | | | In particular, bedside determination of the interstitial hydrostatic & oncotic pressures and the reflection coefficient is not possible. | | | Consider: The erect lung is basically suspended in a gravitational field so the pressure in the vessels at the base of the lung is higher than the pressure at the apex. |
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http://www.qldanaesthesia.com/FluidBook/fl4_4.htm
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| | 4.2 Starling's Hypothesis |
| | This change in net driving pressure is due to the decrease in the capillary hydrostatic pressure along the length of the capillary. | | | An additional point to note here is that the capillary hydrostatic pressure falls along the capillary from the arteriolar to the venous end and the driving pressure will decrease (and typically becomes negative) along the length of the capillary. | | | and whereas capillary pressure determines transudation, the osmotic pressure of the proteids of the serum determines absorption." |
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http://www.qldanaesthesia.com/FluidBook/FL4_2.htm
(797 words)
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| | Glossary - Therapeutic Pillow International |
| | These painful ulcers are caused by restricted circulation (unrelieved pressure) at various pressure points, and result in deterioration of the skin. | | | These painful ulcers are caused by restricted circulation at various pressure points, and result in deterioration of the skin. | | | Visco-elastic, or memory foam is a temperature and pressure sensitive material used in mattresses and pillows to relieve pressure, ease and prevent back and neck problems. |
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http://www.the-pillow.com.au/resources/glossary.shtml
(3587 words)
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| | [No title] |
| | This decrease in hydrostatic pressure (peritubular capillary) and increased oncotic pressure enhance the efficiency of reabsorption of tubular reabsorbate from interstitium into capillary. | | | This is thought to be related to changes in hydrostatic pressure that are transmitted into peritubular capillary and other capillary systems. | | | GFR and RBF tend to maintain constancy despite wide variations in perfusion pressure This tells us that the main change in vascular resistance occurs in the afferent arteriole (since changes in RBF and GFR are similar). |
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http://www.muhealth.org/~md2003/update7/1-22kidney.doc
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| | bmj.com Rapid Responses for Mayor, 328 (7444) 852 |
| | For such oncotic pressure to work it is assumed that the capillary wall is impermeable to albumin, but documented evidence demonstrates this is untrue. | | | There is new physical evidence that such pressure works differently in porous orifice tubes that mimic the capillary structure (1). | | | The documented evidence on capillary structure and function demonstrating that oncotic pressure does not exist in VIVO is summarized here and detailed elsewhere (1). |
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http://bmj.bmjjournals.com/cgi/eletters/328/7444/852-a
(2766 words)
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| | eMedicine - Pulmonary Edema, Cardiogenic : Article by Amal Mattu, MD, FACEP, FAAEM |
| | Increased left atrial pressure increases pulmonary venous pressure and pressure in the lung microvasculature, resulting in pulmonary edema. | | | Cardiogenic pulmonary edema (CPE) is defined as development of pulmonary edema as a consequence of increased capillary hydrostatic pressure secondary to elevated pulmonary venous pressure. | | | Acute mitral valve regurgitation secondary to papillary muscle dysfunction or ruptured chordae tendineae increases LV end-diastolic pressure and represents another cause of pulmonary edema. |
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http://www.emedicine.com/med/topic1955.htm
(7819 words)
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| | The Nephron as a Black Box |
| | Recall the impact of Resistance on Pressure and Flow. | | | One oversimplification is the assumption that there is ample time for water to leave and neatly balance out hydrostatic and oncotic pressures; in reality, this equilibrium is approached, but not reached, especially in settings of increased RBF. | | | Assume that it too does not vary in response to changes in Afferent or Efferent resistance (it’s basically close to the central venous pressure). |
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http://www.columbia.edu/ccnmtl/draft/heart/k1
(938 words)
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| | eMedicine - Congestive Heart Failure and Pulmonary Edema : Article Excerpt by: Shamai Grossman, MD, MS |
| | Backward failure is secondary to elevated systemic venous pressure, while left ventricular failure is secondary to reduced forward flow into the aorta and systemic circulation. | | | Under normal circumstances, when fluid is transferred into the lung interstitium with increased lymphatic flow, no increase in interstitial volume occurs. | | | Pulmonary edema secondary to large negative pleural pressure with increased end expiratory volume |
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http://www.emedicine.com/emerg/byname/congestive-heart-failure-and-pulmonary-edema.htm
(636 words)
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| | [No title] |
| | This is due to the fact that the tubule is very wide and there is no back pressure from downstream. | | | Thus the proximal tubule has an automatic method of self regulating fluid reabsorption to compensate for changes of rates of flow of blood through the glomerular capillaries. | | | There is a net increase in hydrostatic pressure within the interstitium of the kidney which makes it harder for the thick ascending loop of Henley to reabsorb Na into such a high pressure environment. |
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http://www.muhealth.org/~md2003/draft7/1-22kidney.doc
(1090 words)
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| | Related Diseases |
| | The balance of pressure inside and outside of the capillaries and other blood vessels is important for optimal health. | | | The forces within the body work just as then do in our environment. | | | The balance maintained between the two forces (hypertonic and oncotic pressure) acting on the capillaries is crucial to everyone's health. |
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http://www.unc.edu/~rgpatel/Diseases.html
(378 words)
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| | YSM CaseBook: Anthony Diaz |
| | Because this space is drained by systemic veins, fluid may accummulate in any condition in which systemic venous pressure exceeds plasma oncotic pressure. | | | How does the chest x-ray contribute to the physician's understanding of Tony's symptoms and signs? | | | Pulmonary congestion usually results from elevated pulmonary venous pressure, most commonly as a result of left ventricular dysfunction. |
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http://info.med.yale.edu/casebook/renal/diaz/chest_ans_a.html
(180 words)
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| | Oncotic pressure and edema formation in hypoalbuminemic HIV-infected patients with proteinuria. |
| | We conclude that globulins play an important role in maintaining oncotic pressure in low albumin states. | | | Oncotic pressure and edema formation in hypoalbuminemic HIV-infected patients with proteinuria. | | | HIVN patients with increased serum immune globulin may benefit from higher globulin oncotic pressure, delaying the onset of clinical edema in the setting of proteinuria. |
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http://www.aegis.com/aidsline/1998/mar/M9831123.html
(765 words)
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| | Edema tutorial |
| | Why do changes in venous pressure have a greater affect on capillary pressure than changes in arterial pressure? | | | How do changes in each of the following affect capillary pressure: arterial and venous pressures, pre- and postcapillary resistances. | | | What changes in capillary hydrostatic pressure, plasma oncotic pressure, capillary permeability, and lymphatic function can lead to tissue edema? |
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http://www.cvphysiology.com/Tutorials/Tutorial%20-%20capillary%20exchange%20and%20edema.htm
(214 words)
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| | Edema Quiz: Answers |
| | This patient's only systemic symptoms are orthostatic lightheadedness, which correlates with the finding of orthostatic hypotension on the physical exam. | | | Reference also the answer to Question 2; because of the underlying renal PERCEPTION of arterial tree underfilling, adaptive mechanisms designed to defend blood pressure and organ perfusion against HYPOVOLEMIA come into play. | | | Although she has a heart murmur, the normal JVP should rule out right sided CHF, and normal blood pressure and the absence of orthostatic symptoms make you doubt chronic hypovolemia, such as would be the case in chronic covert use of diuretics. |
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http://cc.lrc.usuhs.mil/cc/edema_an.htm
(919 words)
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| | Reabsorption |
| | •Glomerular capillary hydrostatic pressure (): the blood pressure in glomerular capillaries (=60 mmHg) | | | • Baroreceptors respond to changes in blood volume and pressure. | | | Angiotensin II has several actions that increase mean arterial pressure: |
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http://eee.uci.edu/clients/dgromis/kidneys/kidneys.htm
(2004 words)
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| | Hydrostatic & oncotic pressures |
| | Therefore, instead of speaking of "osmotic" pressure, this pressure is referred to as the "oncotic" pressure or "colloid osmotic" pressure because it is generated by colloids. | | | This pressure is determined by the interstitial fluid volume and by the compliance of the tissue, which is related to the ability of the tissue volume to increase. | | | Albumin generates about 70% of the oncotic pressure. |
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http://www.cvphysiology.com/Microcirculation/M012.htm
(659 words)
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| | Albumin - Wikipedia, the free encyclopedia |
| | Because smaller animals (for example rats) function at a lower blood pressure, they need less oncotic pressure to balance this, and thus need less albumin to maintain proper fluid distribution. | | | Nephrotic syndrome patients are given albumin to replace the lost albumin. | | | Albumin is essential for maintaining the oncotic pressure needed for proper distribution of body fluids between intravascular compartments and body tissues. |
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http://en.wikipedia.org/wiki/Albumin
(269 words)
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| | CHEST: Hypoalbuminemia as a Cause of Pleural Effusions |
| | All chest radiographs were reviewed by an investigator who was blind to patients' serum albumin levels, and pleural effusion was defined as a new blunting of the costophrenic angle on the posteroanterior or lateral chest radiograph. | | | Results: Seven of 104 patients in group 1, 2 of 45 patients in group 2, and 3 of 21 patients in group 3 had pleural effusions. | | | In all but two study patients, a careful review of records and a prospective follow-up of the patients' clinical course identified a potential cause for the effusions other than hypoalbuminemia. |
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http://www.findarticles.com/p/articles/mi_m0984/is_4_115/ai_54514686
(1201 words)
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| | Quiz 2 Answers |
| | Tissue oncotic and hydrostatic pressures also influence the net movement of water. | | | Pressures in lymphatics and veins are low and may cycle such that at times the upstream pressure could be greater than the downstream pressure. | | | Normally, the greatest force for filtration (movement of water from the capillary to the tissue) is the capillary hydrostatic pressure; and the largest force for absorption (movement from the tissue to capillary) is the plasma oncotic pressure. |
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http://www.iuvascular.com/Unthank/Teach/Quiz2Answers.html
(516 words)
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| | Web demo for MCQS |
| | The capillaries are more permeable to albumin in comparison with other capillaries in the body. | | | The oncotic pressure of the plasma leaving the capillaries is lower than the general systemic oncotic pressure.. | | | Constriction of the afferent arteriole causes the capillary blood pressure to fall. |
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http://www.staff.ncl.ac.uk/david.sanders/mcq/mcq14.htm
(66 words)
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| | Article #2447, Low Postoperative Hematocrit Increases Cerebrovascular Damage After Hypothermic Circulatory Arrest |
| | Measurements and Results: Changes in body weight, bioimpedance, and colloid oncotic pressure were assessed. | | | Postoperative hematocrit management may have profound systemic and cerebral effects after deep hypothermic circulatory arrest and merits further investigation. | | | Conclusons: Lower postoperative hematocrit was associated with increased fluid retention, lower perfusion pressure, and worse cerebrovascular injury following deep hypothermic circulatory arrest. |
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http://www.perfusion.com/cgi-bin/absolutenm/templates/mobilearticledisplay.asp?articleid=2447
(358 words)
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| | Fluid & Electrolyte Therapy |
| | The net pressure into capillary increases and the balance is no longer maintained so fluid is retrieved into the circulation from the interstitium until Pc is restored. | | | useful in treating hypoproteinemia and maintaining normal colloidal osmotic pressure | | | One gram of albumin exerts twice the colloid osmotic pressure of a gram of globulin |
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http://www.cvm.okstate.edu/courses/vmed5412/Lect017.htm
(1480 words)
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| | renal.html |
| | So, keeping in mind that filtration is primarily a function of capillary hydrostatic pressure, what effect would constricting or dilating the afferent and/or efferent arteriole have on GFR? | | | With constriction of the afferent arteriole, glomerular capillary hydrostatic pressure and flow are reduced, which decreases GFR. | | | Renin is released in response to sympathetic stimulation and is important in blood pressure and fluid volume regulation. |
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http://carbon.cudenver.edu/~rtyler/renal.html
(1633 words)
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| | Study Guide: Fluid, Electrolyte, and Acid-Base Balance |
| | the difference between the colloid osmotic, or oncotic, pressure and hydrostatic pressure | | | the pressure exerted by water within a closed system on the wall of a container in which it is contained; "water-pushing pressure" | | | the pressure exerted by solutes in water; "water-pulling pressure" |
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http://www4.desales.edu/~sey0/study33.html
(507 words)
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| | Acute Pulmonary Edema - Medstudents- Intensive Care |
| | The opposing forces that most likely are responsable for fluid transference to interstitium are : 1-Pumonary capilar pressure 2- Plasma oncotic pressure | | | It also dilates the epicardial coronaries and, therefore, is a treatment for ischemia, which can be the underlying cause of the pulmpnary edema. | | | NTG may be repeated twice at five minute intervals, as long as there is no important fall in blood pressure, and it should not be given to any patient with a systolic blood pressure <120 mmHg, unless an IV line is in place. |
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http://www.medstudents.com.br/terin/terin7.htm
(1586 words)
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| | HDCN: Review of abstract by Guardia et al. Contribution of globulins to plasma oncotic pressure and the ... |
| | Contribution of globulins to plasma oncotic pressure and the presence of edema in HIV patients with proteinuria | | | The authors conclude that relatively higher oncotic pressures related to plasma globulins may delay the onset of edema in HIV infected patients. | | | Contribution of globulins to plasma oncotic pressure and the presence of edema in HIV patients with proteinuria (1995 ASN Meeting) |
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http://www.hdcn.com/ab/5asnguar.htm
(280 words)
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| | Fluids and Electrolytes |
| | The oncotic forces within the capillary are balanced by the hydrostatic pressure (generated from cardiac contraction). | | | This system is referred to as the Renin-Angiotensin system. | | | An important point is that a small amount of fluid is reabsorbed from the interstitial space by the lymph channels (recall the swelling that is associated with removal of the lymph nodes and vessels in cancer patients). |
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http://www.lander.edu/tmaze/Pathology/Lectures%20Fall%202003/6.%20Fluid,%20Electrolytes,%20Acids%20and%20Bases.htm
(2006 words)
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| | VPX Information - Plasma Expanders |
| | While antihistamines may be effective in relieving the allergic reactions, the anaphylactoid reactions are considered emergencies and should be treated as such. | | | For example, if albumin is used it may exert a stronger oncotic effect than the other blood-volume expanders; consequently, this may seem attractive to some bodybuilders who may be retaining "excess" extracellular water prior to a contest. | | | This may be significant to bodybuilders because the amount of oncotic pressure a solution exerts determines, in a sense, the relative strength of these products. |
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http://www.vpxsports.com/plasmaExpanders.html
(1802 words)
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| | 2.4 Colloid Oncotic Pressure |
| | The component of the total osmotic pressure due to the colloids is known as colloid osmotic pressure or as oncotic pressure. | | | This increase of 6 to 7 mmol/l is much more than the 0.4 mOsm/l required to account for the increase in oncotic pressure. | | | The osmotic pressure (and also the oncotic pressure) for an ideal solution can be calculated by appropriate substitutions in the van’t Hoff equation. |
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http://www.qldanaesthesia.com/FluidBook/fl2_4.htm
(740 words)
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| | Starling's hypothesis - General Practice Notebook |
| | This 'filtration force' is dependent on the blood pressure, itself dependent on the force with which the heart is pumping and the local vascular resistance. | | | Forces causing water to move into the intravascular compartment include the oncotic pressure and the interstitial tissue hydrostatic pressure. | | | Starling hypothesised that the extent of water and small solute transit in any one direction across a capillary is dependent upon the balance of two opposing forces. |
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http://www.gpnotebook.co.uk/cache/1731526716.htm
(305 words)
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| | UpToDate Chapter 7B: Exchange of water between plasma and interstitial fluid |
| | Fluid does not continuously move into the capillary because the oncotic pressure is largely balanced by the capillary hydraulic (or hydrostatic) pressure. | | | This pressure is generated by the propulsion of blood from the heart and tends to push water out of the vessels into the interstitium. | | | This osmotic pressure generated by the plasma proteins is called the colloid osmotic pressure or the plasma oncotic pressure. |
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http://patients.uptodate.com/topic.asp?file=ren_phys/10933&title=undefined
(416 words)
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| | Edema |
| | As mentioned in the answer to Question 3, patients with "idiopathic" edema often have a history of use of diuretics for dubious indications, such as weight control. | | | You always want to check edematous patients for stigmata of CHF: elevated jugular venous pressure, due to increased right heart filling pressure; pulmonary rales, due to fluid in the pulmonary interstitium; and S3 gallop, due to ventricular dysfunction. | | | This can be on the basis of generalized vasodilation (such as in anaphylaxis, sepsis, and cirrhosis), slight intravascular volume depletion (as in chronic diuretic abuse for weight control ["idiopathic edema"]), reduced plasma oncotic pressure (nephrotic syndrome), or reduced cardiac output due to congestive heart failure. |
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http://cc.lrc.usuhs.mil/cc/ccedema.htm
(677 words)
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| | Oncotic pressure - Wikipedia, the free encyclopedia |
| | Because large plasma proteins can't easily cross through the capillary walls, their effect on the osmotic pressure of the capillary interiors will, to some extent, balance out the tendency for fluid to leak out of the capillaries. | | | from being lost in the urine (proteinuria) or from malnutrition, the result of the too low oncotic pressure can be oedema - excess fluid buildup in the tissues. | | | This page was last modified 14:31, 10 October 2005. |
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http://en.wikipedia.org/wiki/Oncotic_pressure
(137 words)
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| | Howstuffworks "How Blood Works" |
| | Proteins make up a large part of the 10 percent of material dissolved in plasma and are responsible for oncotic pressure. | | | These proteins function to maintain oncotic pressure (especially albumin) and transport substances such as lipids, hormones, medications, vitamins, and other nutrients. | | | These proteins are also part of the immune system (immunoglobulins), help blood to clot (clotting factors), maintain pH balance, and are enzymes involved in chemical reactions throughout the body. |
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http://www.howstuffworks.com/blood9.htm
(477 words)
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| | Peripheral oedema - Patient UK |
| | Renal (decreased oncotic pressure from protein loss, and increased fluid pressure from sodium and water retention): acute nephritic syndrome, nephrotic syndrome. | | | A 70kg adult male has 12 litres of interstitial fluid (30% of total body water), and it is generally considered a 15% increase (2 litres extra) is required for clinical oedema. | | | Local infection, trauma (including burns), animal bites or stings (increased capillary permeability, and increased interstitial oncotic pressure in inflammatory response, also in burns generalised oedema from decreased oncotic pressure from protein loss). |
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http://www.patient.co.uk/showdoc/40000104
(705 words)
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| | University of Iowa Anesthesia Publications |
| | To study the effect of oncotic pressure on brain water content during cardiopulmonary bypass (CPB), 14 anesthetized New Zealand White rabbits underwent 60 min of nonpulsatile CPB at normothermia. | | | There were no significant differences between groups 1 and 2 with respect to temperature, central venous pressure, mean arterial pressure, PaO2, PaCO2, plasma sodium concentration, or osmolality at any time during CPB, although osmolality increased in both groups. | | | Differential effect of oncotic pressure on cerebral and extracerebral water content during cardiopulmonary bypass in rabbits. |
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http://www.anesth.uiowa.edu/readabstract.asp?PMID=2240684
(296 words)
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| | plasma oncotic pressure Post 22751 Forums PLAB AIPPG USMLE |
| | The osmotic pressure produced by proteins(ie., the capacity to attract water) is called oncotic pressure. | | | I am afraid the question should be osmotic pressure, not oncotic pressure. | | | Since there is no ans as 0.03atm the question could be osmotic pressure. |
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http://www.aipge.com/postp22751.html
(214 words)
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| | Oncotic pressure |
| | A small portion of the total pressure is due to the presence of protein molecules; this is known as the colloidal osmotic pressure or oncotic pressure. | | | Because large plasma proteins can't easily through the capillary walls their effect on the osmotic of the capillary interiors will to some balance out the tendency for fluid to out of the capillaries. | | | The book explains the types of interest groups and why people join them. |
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http://www.freeglossary.com/Oncotic_pressure
(465 words)
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| | Assessment Test |
| | Albumin is absorbed from the inflamed pulpal interstitial tissue by the adjacent lymphatic channels. | | | An increase in permeability of the capillary endothelium to albumin would increase the tissue oncotic pressure. | | | Blood flows from the low pressure TA into the high pressure PCV |
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http://www.uth.tmc.edu/courses/dental/pulpalmicro/assessment_test.htm
(386 words)
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| | Vapor Pressure Osmometer |
| | Colloid Osmometer Osmotic (Oncotic) Pressure Pulmonary Edema Prediction Discover... | | | Correction for loss of CO2 from blood during measurement of osmotic pressure --... | | | Vapro Vapor Pressure Osmometer Osmotic Measurement Whole blood Viscous samples T... |
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http://www.scienceoxygen.com/apparatus/216.html
(213 words)
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