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Osteonecrosis Of The Jaw
Osteonecrosis of the jaw (ONJ) is a severe bone disease (osteonecrosis) that affects the jaws (the maxilla and the mandible). Various forms of ONJ have been described since 1861, and a number of causes have been suggested in the literature. Osteonecrosis of the jaw associated with bisphosphonate therapy, which is required by some cancer treatment regimens, has been identified and defined as a pathological entity ( bisphosphonate-associated osteonecrosis of the jaw) since 2003.(webpage has a translation button) The possible risk from lower oral doses of bisphosphonates, taken by patients to prevent or treat osteoporosis, remains uncertain. Treatment options have been explored; however, severe cases of ONJ still require surgical removal of the affected bone. A thorough history and assessment of pre-existing systemic problems and possible sites of dental infection are required to help prevent the condition, especially if bisphosphonate therapy is considered. Signs and symptoms The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteonecrosis
Avascular necrosis (AVN), also called osteonecrosis or bone infarction, is death of bone tissue due to interruption of the blood supply. Early on, there may be no symptoms. Gradually joint pain may develop, which may limit the person's ability to move. Complications may include collapse of the bone or nearby joint surface. Risk factors include bone fractures, joint dislocations, alcoholism, and the use of high-dose steroids. The condition may also occur without any clear reason. The most commonly affected bone is the femur (thigh bone). Other relatively common sites include the upper arm bone, knee, shoulder, and ankle. Diagnosis is typically by medical imaging such as X-ray, CT scan, or MRI. Rarely biopsy may be used. Treatments may include medication, not walking on the affected leg, stretching, and surgery. Most of the time surgery is eventually required and may include core decompression, osteotomy, bone grafts, or joint replacement. About 15,000 cases occur pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone is the skull's only movable, posable bone, sharing Temporomandibular joint, joints with the cranium's temporal bones. The mandible hosts the lower Human tooth, teeth (their depth delineated by the alveolar process). Many muscles attach to the bone, which also hosts nerves (some connecting to the teeth) and blood vessels. Amongst other functions, the jawbone is essential for chewing food. Owing to the Neolithic Revolution, Neolithic advent of agriculture (), human jaws evolved to be Human jaw shrinkage, smaller. Although it is the strongest bone of the facial skeleton, the mandible tends to deform in old age; it is also subject to Mandibular fracture, fracturing. Surgery allows for the removal of jawbone fragments (or its entirety) as well a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperemia
Hyperaemia (also hyperemia) is the increase of blood flow to different tissues in the body. It can have medical implications but is also a regulatory response, allowing change in blood supply to different tissues through vasodilation (widening of blood vessels). Clinically, hyperaemia in tissues manifests as erythema (redness of the skin) because of the engorgement of vessels with oxygenated blood. Hyperaemia can also occur due to a fall in atmospheric pressure outside the body. The term comes . Regulation of blood flow Functional hyperaemia is an increase in blood flow to a tissue due to the presence of metabolites and a change in general conditions. When a tissue increases its activity, there is a well-characterized fall in the partial pressure of oxygen and pH, along with an increase in partial pressure of carbon dioxide, and a rise in temperature and the concentration of potassium ions. The mechanisms of vasodilation are predominantly local metabolites and myogenic eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrinolysis
Fibrinolysis is a process that prevents blood clots from growing and becoming problematic. Primary fibrinolysis is a normal body process, while secondary fibrinolysis is the breakdown of clots due to a medicine, a medical disorder, or some other cause. In fibrinolysis, a fibrin clot, the product of coagulation, is broken down. Its main enzyme plasmin cuts the fibrin mesh at various places, leading to the production of circulating fragments that are cleared by other proteases or by the kidney and liver. Physiology Plasmin is produced in an inactive form, plasminogen, in the liver. Although plasminogen cannot cleave fibrin, it still has an affinity for it, and is incorporated into the clot when it is formed. Tissue plasminogen activator (t-PA) and urokinase are the agents that convert plasminogen to the active plasmin, thus allowing fibrinolysis to occur. t-PA is released into the blood slowly by the damaged endothelium of the blood vessels, such that, after several days (when th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasminogen Activator Inhibitor-1
Plasminogen activator inhibitor-1 (PAI-1) also known as endothelial plasminogen activator inhibitor (serpin E1) is a protein that in humans is encoded by the ''SERPINE1'' gene. Elevated PAI-1 is a risk factor for thrombosis and atherosclerosis. PAI-1 is a serine protease inhibitor ( serpin) that functions as the principal inhibitor of tissue-type plasminogen activator (tPA) and urokinase (uPA), the activators of plasminogen and hence fibrinolysis (the physiological breakdown of blood clots). It is a serine protease inhibitor (serpin) protein (SERPINE1). The other PAI, plasminogen activator inhibitor-2 (PAI-2) is secreted by the placenta and only present in significant amounts during pregnancy. In addition, protease nexin acts as an inhibitor of tPA and urokinase. PAI-1, however, is the main inhibitor of the plasminogen activators. Genetics The PAI-1 gene is ''SERPINE1'', located on chromosome 7 (7q21.3-q22). There is a common polymorphism known as 4G/5G in the promoter reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadmium
Cadmium is a chemical element; it has chemical symbol, symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12 element, group 12, zinc and mercury (element), mercury. Like zinc, it demonstrates oxidation state +2 in most of its compounds, and like mercury, it has a lower melting point than the transition metals in group 3 element, groups 3 through group 11 element, 11. Cadmium and its Congener (chemistry), congeners in group 12 are often not considered transition metals, in that they do not have partly filled ''d'' or ''f'' electron shells in the elemental or common oxidation states. The average concentration of cadmium in Earth's crust is between 0.1 and 0.5 parts per million (ppm). It was discovered in 1817 simultaneously by Friedrich Stromeyer, Stromeyer and Karl Samuel Leberecht Hermann, Hermann, both in Germany, as an impurity in zinc carbonate. Cadmium occurs as a minor component in most zinc ores and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead
Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleable, and also has a relatively low melting point. When freshly cut, lead is a shiny gray with a hint of blue. It tarnishes to a dull gray color when exposed to air. Lead has the highest atomic number of any stable nuclide, stable element and three of its isotopes are endpoints of major nuclear decay chains of heavier elements. Lead is a relatively unreactive post-transition metal. Its weak metallic character is illustrated by its Amphoterism, amphoteric nature; lead and lead oxides react with acids and base (chemistry), bases, and it tends to form covalent bonds. Lead compounds, Compounds of lead are usually found in the +2 oxidation state rather than the +4 state common with lighter members of the carbon group. Exceptions are mostly limited ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy Metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals is a controversial and ambiguous term for metallic elements with relatively high density, densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context and it has been argued that the term "heavy metal" should be avoided. A heavy metal may be defined on the basis of density, atomic number or chemical behaviour. More specific definitions have been published, none of which have been widely accepted. The definitions surveyed in this article encompass up to 96 out of the 118 known chemical elements; only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm3 is sometimes quoted as a commonly used criterion and is used in the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombophilia
Thrombophilia (sometimes called hypercoagulability or a prothrombotic state) is an abnormality of blood coagulation that increases the risk of thrombosis (blood clots in blood vessels). Such abnormalities can be identified in 50% of people who have an episode of thrombosis (such as deep vein thrombosis in the leg) that was not provoked by other causes. A significant proportion of the population has a detectable thrombophilic abnormality, but most of these develop thrombosis only in the presence of an additional risk factor. There is no specific treatment for most thrombophilias, but recurrent episodes of thrombosis may be an indication for long-term preventive anticoagulant, anticoagulation. The first major form of thrombophilia to be identified by medical science, antithrombin deficiency, was identified in 1965, while the most common abnormalities (including factor V Leiden) were described in the 1990s. Signs and symptoms The most common conditions associated with thrombophi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombosis
Thrombosis () is the formation of a Thrombus, blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (thrombocytes) and fibrin to form a blood clot to prevent blood loss. Even when a blood vessel is not injured, blood clots may form in the body under certain conditions. A clot, or a piece of the clot, that breaks free and begins to travel around the body is known as an embolus. Thrombosis can cause serious conditions such as stroke and heart attack. Thrombosis may occur in veins (venous thrombosis) or in arteries (arterial thrombosis). Venous thrombosis (sometimes called DVT, deep vein thrombosis) leads to a blood clot in the affected part of the body, while arterial thrombosis (and, rarely, severe venous thrombosis) affects the blood supply and leads to damage of the tissue supplied by that artery (ischemia and necrosis). A piece of either an arterial or a v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypercoagulability
Thrombophilia (sometimes called hypercoagulability or a prothrombotic state) is an abnormality of blood coagulation that increases the risk of thrombosis (blood clots in blood vessels). Such abnormalities can be identified in 50% of people who have an episode of thrombosis (such as deep vein thrombosis in the leg) that was not provoked by other causes. A significant proportion of the population has a detectable thrombophilic abnormality, but most of these develop thrombosis only in the presence of an additional risk factor. There is no specific treatment for most thrombophilias, but recurrent episodes of thrombosis may be an indication for long-term preventive anticoagulation. The first major form of thrombophilia to be identified by medical science, antithrombin deficiency, was identified in 1965, while the most common abnormalities (including factor V Leiden) were described in the 1990s. Signs and symptoms The most common conditions associated with thrombophilia are deep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
