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Dicumarol
Dicoumarol ( INN) or dicumarol ( USAN) is a naturally occurring anticoagulant drug that depletes stores of vitamin K (similar to warfarin, a drug that dicoumarol inspired). It is also used in biochemical experiments as an inhibitor of reductases. Dicoumarol is a natural chemical substance of combined plant and fungal origin. It is a derivative of coumarin, a bitter-tasting but sweet-smelling substance made by plants that does not itself affect coagulation, but which is (classically) transformed in mouldy feeds or silages by a number of species of fungi, into active dicoumarol. Dicoumarol does affect coagulation, and was discovered in mouldy wet sweet-clover hay, as the cause of a naturally occurring bleeding disease in cattle. See warfarin for a more detailed discovery history. Identified in 1940, dicoumarol became the prototype of the 4-hydroxycoumarin anticoagulant drug class. Dicoumarol itself, for a short time, was employed as a medicinal anticoagulant drug, but since the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prothrombin Time
The prothrombin time (PT) – along with its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) – is an assay for evaluating the Coagulation#Extrinsic pathway, extrinsic pathway and Coagulation#Common pathway, common pathway of coagulation. This blood test is also called ''protime INR'' and ''PT/INR''. They are used to determine the Thrombophilia, clotting tendency of blood, in conditions such as the measure of warfarin dosage, liver damage (cirrhosis), and vitamin K status. PT measures the following Coagulation#Coagulation factors, coagulation factors: fibrinogen, I (fibrinogen), thrombin, II (prothrombin), Factor V, V (proaccelerin), Factor VII, VII (proconvertin), and Factor X, X (Stuart–Prower factor). PT is often used in conjunction with the partial thromboplastin time, activated partial thromboplastin time (aPTT) which measures the Coagulation#intrinsic pathway, ''intrinsic'' pathway and common pathway of coagulation. Laboratory measur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticoagulant
An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which help keep the bite area unclotted long enough for the animal to obtain blood. As a class of medications, anticoagulants are used in therapy for thrombotic disorders. Oral anticoagulants (OACs) are taken by many people in pill or tablet form, and various intravenous anticoagulant dosage forms are used in hospitals. Some anticoagulants are used in medical equipment, such as sample tubes, blood transfusion bags, heart–lung machines, and dialysis equipment. One of the first anticoagulants, warfarin, was initially approved as a rodenticide. Anticoagulants are closely related to antiplatelet drugs and thrombolytic drugs by manipulating the various pathways of blood coagulation. Specifically, antiplatelet drugs inhibit platelet agg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coumarin Drugs
Coumarin () or 2''H''-chromen-2-one is an aromatic organic chemical compound with formula . Its molecule can be described as a benzene molecule with two adjacent hydrogen atoms replaced by an unsaturated lactone ring , forming a second six-membered heterocycle that shares two carbons with the benzene ring. It belongs to the benzopyrone chemical class and is considered a lactone. Coumarin is a colorless crystalline solid with a sweet odor resembling the scent of vanilla and a bitter taste. It is found in many plants, where it may serve as a chemical defense against predators. While coumarin is not an anticoagulant, its 3-alkyl-4-hydroxy derivatives, such as the fungal metabolite dicoumarol, inhibit synthesis of vitamin K, a key component in blood clotting. A related compound, the prescription drug anticoagulant warfarin, is used to inhibit formation of blood clots, deep vein thrombosis, and pulmonary embolism. Etymology Coumarin is derived from , the French word for the tonka ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warfarin
Warfarin, sold under the brand name Coumadin among others. It is used as an anticoagulant, anticoagulant medication. It is commonly used to prevent deep vein thrombosis and pulmonary embolism, and to protect against stroke in people who have atrial fibrillation, valvular heart disease, or artificial heart valves. Warfarin may sometimes be prescribed following a ST-segment elevation myocardial infarction and orthopedic surgery. It is usually taken by mouth, but may also be administered intravenously. The common side effect, a natural consequence of reduced clotting, is bleeding. Less common side effects may include areas of tissue necrosis, tissue damage, and purple toes syndrome. Use is not recommended during pregnancy. The effects of warfarin are typically monitored by checking prothrombin time (INR) every one to four weeks. Many other medications and Diet (nutrition), dietary factors can interact with warfarin, either increasing or decreasing its effectiveness. The effec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coumarin
Coumarin () or 2''H''-chromen-2-one is an aromatic organic chemical compound with formula . Its molecule can be described as a benzene molecule with two adjacent hydrogen atoms replaced by an unsaturated lactone ring , forming a second six-membered heterocycle that shares two carbons with the benzene ring. It belongs to the benzopyrone chemical class and is considered a lactone. Coumarin is a colorless crystalline solid with a sweet odor resembling the scent of vanilla and a bitter taste. It is found in many plants, where it may serve as a chemical defense against predators. While coumarin is not an anticoagulant, its 3-alkyl-4-hydroxy derivatives, such as the fungal metabolite dicoumarol, inhibit synthesis of vitamin K, a key component in blood clotting. A related compound, the prescription drug anticoagulant warfarin, is used to inhibit formation of blood clots, deep vein thrombosis, and pulmonary embolism. Etymology Coumarin is derived from , the French word for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Paul Link
Karl Paul Gerhard Link (31 January 1901 – 21 November 1978) was an American biochemist best known for his discovery of the anticoagulant warfarin. Training and early career Link was born in LaPorte, Indiana to a Lutheran minister of German descent as one of ten children. He was schooled locally, and attended the University of Wisconsin–Madison, where he studied agricultural chemistry at the College of Agriculture from 1918 to 1925, obtaining an MS in 1923 and a PhD in 1925. He was then chosen by the national Education Board for a postdoctoral scholarship, and relocated to Europe. He briefly worked with carbohydrate chemist Sir James Irvine at the University of St Andrews in Scotland and from 1926 in Graz, Austria with Fritz Pregl, inventor of microchemistry and Nobel Laureate. Finally he spent several months with organic chemist and future Nobel laureate Paul Karrer in the latter's lab in Zurich; during this period Link had tuberculosis, requiring recuperation in Dav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin K Antagonists
Vitamin K antagonists (VKA) are a group of substances that reduce blood clotting by reducing the action of vitamin K. The term "vitamin K antagonist" is technically a misnomer, as the drugs do not directly antagonize the action of vitamin K in the pharmacological sense, but rather the recycling of vitamin K. Vitamin K antagonists (VKAs) have been the mainstay of anticoagulation therapy for more than 50 years. They are used as anticoagulant medications in the prevention of thrombosis, and in pest control, as rodenticides. Mechanism of action These drugs deplete the active form of the vitamin by inhibiting the enzyme vitamin K epoxide reductase and thus the recycling of the inactive vitamin K epoxide back to the active reduced form of vitamin K. The drugs are structurally similar to vitamin K and act as competitive inhibitors of the enzyme. The term "vitamin K antagonist" is a misnomer, as the drugs do not directly antagonise the action of vitamin K in the pharmacological sens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Biscoumacetate
Ethyl biscoumacetate is a vitamin K Vitamin K is a family of structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-translational modification, post-synthesis modification of certain proteins ... antagonist. References * The Merck Index, 12th Edition. 3818 Coumarin drugs Ethyl esters {{blood-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Great Depression
The Great Depression was a severe global economic downturn from 1929 to 1939. The period was characterized by high rates of unemployment and poverty, drastic reductions in industrial production and international trade, and widespread bank and business failures around the world. The economic contagion began in 1929 in the United States, the largest economy in the world, with the devastating Wall Street stock market crash of October 1929 often considered the beginning of the Depression. Among the countries with the most unemployed were the U.S., the United Kingdom, and Germany. The Depression was preceded by a period of industrial growth and social development known as the "Roaring Twenties". Much of the profit generated by the boom was invested in speculation, such as on the stock market, contributing to growing wealth inequality. Banks were subject to minimal regulation, resulting in loose lending and widespread debt. By 1929, declining spending had led to reductions in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agricultural Extension
Agricultural extension is the application of scientific research and new knowledge to agricultural practices through farmer education. The field of 'extension' now encompasses a wider range of communication and learning activities organized for rural people by educators from different disciplines, including agriculture, agricultural marketing, health, and business studies. Extension practitioners can be found throughout the world, usually working for government agencies. They are represented by several professional organizations, networks and extension journals. Agricultural extension agencies in developing countries receive large amounts of support from international development organizations such as the World Bank and the Food and Agriculture Organization of the United Nations. Extension terminology The use of the word 'extension' originated in England in 1866. Modern extension began in Dublin, Ireland in 1847 with Lord Clarendon's itinerant instructors during the Great ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemorrhage
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vagina, or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination. Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties (by comparison, blood donation typically takes 8–10% of the donor's blood volume). The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery. Types * Upper head ** Intracranial hemorrhage — bleeding in the skull. ** Cerebral hemorrhage — a type of intracranial hemorrhage, bleeding within the brain tissue itself. ** Intracerebral hemorrhage — bleeding in the brain caused by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
