Systemic blood

The resting membrane potential of most excitable cells is around —60 to —80 mV. This gradient is maintained by the activity of various ion channels. When the potassium channels of the cell open, potassium efflux occurs and hyperpolari2ation results. This decreases calcium channel openings, which ia turn preveats the influx of calcium iato the cell lea ding to a decrease ia iatraceUular calcium ia the smooth muscles of the vasculature. The vascular smooth muscles thea relax and the systemic blood pressure faUs. 

At normal systemic-blood glucose concentrations (4.5-5.5 mmol/L), the liver is a net producer of glucose. However, as the glucose level rises, the output of glucose ceases, and there is a net uptake. 

The ammonia produced by enteric bacteria and absorbed into portal venous blood and the ammonia produced by tissues are rapidly removed from circulation by the liver and converted to urea. Only traces (10—20 Ig/dL) thus normally are present in peripheral blood. This is essential, since ammonia is toxic to the central nervous system. Should portal blood bypass the liver, systemic blood ammonia levels may rise to toxic levels. This occurs in severely impaired hepatic function or the development of collateral links between the portal and systemic veins in cirrhosis. Symptoms of ammonia intoxication include tremor, slurred speech, blurred vision, coma, and ultimately death. Ammonia may be toxic to the brain in part because it reacts with a-ketoglutarate to form glutamate. The resulting depleted levels of a-ketoglutarate then impair function of the tricarboxylic acid (TCA) cycle in neurons. 

In stroke patients presenting to the ED, the first goal of treatment is immediate cardiac and respiratory stabilization. The systemic blood pressure is most often elevated in the setting of an acute stroke as the result of a catecholamine surge, and if the patient is hypotensive, the clinician should consider a concomitant cardiac process, such as myocardial infarction (MI), congestive heart failure (CHF), or pulmonary embolism (PE). 

The BBB is a complex cellular system which protects the central nervous system (CNS) by separating the brain from the systemic blood circulation. Drugs that act... 

The sinusoids transport both portal and arterial blood to the hepatocytes. The systemic blood delivered to the liver contains nutrients, drugs, and ingested toxins. The liver processes the nutrients (carbohydrates, proteins, lipids, vitamins, and minerals) for either immediate use or for storage, while the drugs and toxins are metabolized through a variety of processes known as first-pass metabolism. The liver also processes metabolic waste products for excretion. In cirrhosis, bilirubin (from the enzymatic breakdown of heme) can accumulate this causes jaundice (yellowing of the skin), scleral icterus (yellowing of the sclera), and tea-colored urine (urinary bilirubin excretion). 

Systemic blood pressure correlates with glomerular pressure and elevations in both systemic blood pressure and glomerular pressure contribute to glomerular damage. The rate of GFR decline is related to elevated systolic blood pressure and mean arterial pressure. The decline in GFR is estimated to be 14 mL/minute per year with a systolic blood pressure of 180 mm Hg. Conversely, the decline in GFR decreases to 2 mL/minute per year with a systolic blood pressure of 135 mm Hg.11... 

Peripheral resistance The sum of resistance to blood flow offered by systemic blood vessels. 

Recycling of printer circuit boards is deemed as the most important source of heavy metals to the ambient environment. These heavy metals may be entering into human body from various exposure routes such as ingestion, inhalation, and dermal absorption. Exposure to high levels of heavy metals can lead to acute and chronic toxicity, such as damage to central and peripheral nervous systems, blood composition, lungs, kidneys, liver, and even death [14],... 

Blood-brain barrier A physicochemical barrier formed by astrocytes and capillary endothelial cells. It prevents toxic chemicals from entering CNS neurons from the systemic blood circulation. 

The answer is a. (Hardman, pp 762-764.) Experimentally, nitrates dilate coronary vessels. This occurs in normal subjects, resulting in an overall increase in coronary blood flow. In arteriosclerotic coronaries, the ability to dilate is lost, and the ischemic area may actually have less blood flow under the influence of nitrates. Improvement in the ischemic conditions is the result of decreased myocardial oxygen demand because of a reduction of preload and afterload. Nitrates dilate both arteries and veins and thereby reduce the work of the heart. Should systemic blood pressure fall, a reflex tachycardia will occur. In pure coronary spasm, such as Prinzmetal s angina, the effect of increased coronary blood flow is relevant, while in severe left ventricular hypertrophy with minimal obstruction, the effect on preload and afterload becomes important. 

Reliable correlations were found between lead concentrations in the soil and the incidence rates in the population of Dnepropetrovsk. In the adults, the pollution levels were associated with complications in pregnancy and delivery, diseases of urogenital, nervous and bone-and-muscular system, blood problems and tumors. In the children, the blood, blood forming organs, respiratory system and the muscles and bones were most frequently affected. 

Angiotensin II is an octapeptide hormone that plays an important role in the regulation of the cardiovascular system (blood pressure and sustained hyperten-... 

SP produces a pronounced (4-fold) increase in the histamine content of the venus outflow of the perfused rat hindquarters [91] and, when injected intravenously in intact animals, it produces a significant increase in the level of plasma histamine and in the hematocrit and a pronounced fall in systemic blood pressure [102], In these experiments, pretreatment with the steroid, dexamethasone, reduced the SP-induced elevations in plasma histamine and hematocrit neurotensin and compound 48/80 were found to be similarly... 

In pure liquid form, lewisite causes blindness, immediate destruction of lung tissue, and systemic blood poisoning. It is absorbed through the skin like distilled mustard, but is much more toxic to the skin. Skin exposure results in immediate pain a rash forms within 30 minutes. Severe chemical burns are possible. Blistering of the skin takes up to 13 hours to develop. Lewisite does not dissolve in human sweat. It commingles with sweat, then flows to tender skin areas such as the inner arm, buttocks, and crotch. 

Immediate destruction of lung tissue Systemic blood poisoning... 

DTPA-SWNTs or DTPA-MWNTs labelled with111 In (0.06 or 0.4mg/ mouse) Female BALB/c mice Intravenous administration 30 min, 3h, and No toxic side effects, accumulation, or 24 h mortalities were observed. CNTs were removed from systemic blood circulation though the renal excretion route Singh et al. (2006)... 

Assuming the capsular pressures opposing the movement of water out of the blood and into the top of the nephron are constant, the net filtration pressure is due largely to the blood pressure. Any fall in blood pressure can have a dramatic effect on the efficiency of filtration and therefore clearance of waste materials. So important is the pressure within the renal vasculature that the kidney is critical in regulating systemic blood pressure via the renin-angiotensin-aldosterone (RAA) axis, a physiological process which relies on transport mechanisms within the renal tubules. 

Systemic blood pressure is a function of vascular resistance and cardiac output SBP = CO x SVR... 

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