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Anticoagulants
Anticoagulants, commonly known as blood thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time. Some of them occur naturally in blood-eating animals such as leeches and mosquitoes, where they help keep the bite area unclotted long enough for the animal to obtain some 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] |
Rodenticide
Rodenticides are chemicals made and sold for the purpose of killing rodents. While commonly referred to as "rat poison", rodenticides are also used to kill mice, squirrels, woodchucks, chipmunks, porcupines, nutria, beavers, and voles. Despite the crucial roles that rodents play in nature, there are times when they need to be controlled. Some rodenticides are lethal after one exposure while others require more than one. Rodents are disinclined to gorge on an unknown food (perhaps reflecting an adaptation to their inability to vomit), preferring to sample, wait and observe whether it makes them or other rats sick. This phenomenon of poison shyness is the rationale for poisons that kill only after multiple doses. Besides being directly toxic to the mammals that ingest them, including dogs, cats, and humans, many rodenticides present a secondary poisoning risk to animals that hunt or scavenge the dead corpses of rats. Classes of rodenticides Anticoagulants Anticoagulant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warfarin
Warfarin, sold under the brand name Coumadin among others, is a medication that is used as an anticoagulant (blood thinner). It is commonly used to prevent blood clots such as deep vein thrombosis and pulmonary embolism, and to prevent stroke in people who have atrial fibrillation, valvular heart disease, or artificial heart valves. Less commonly, it is used following ST-segment elevation myocardial infarction and orthopedic surgery. It is generally taken by mouth, but may also be used intravenously. The common side effect is bleeding. Less common side effects may include areas of tissue damage and purple toes syndrome. Use is not recommended during pregnancy. The effects of warfarin typically should be monitored by checking prothrombin time (INR) every one to four weeks. Many other medications and dietary factors can interact with warfarin, either increasing or decreasing its effectiveness. The effects of warfarin may be reversed with phytomenadione (vitamin K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Vein Thrombosis
Deep vein thrombosis (DVT) is a type of venous thrombosis involving the formation of a blood clot in a deep vein, most commonly in the legs or pelvis. A minority of DVTs occur in the arms. Symptoms can include pain, swelling, redness, and enlarged veins in the affected area, but some DVTs have no symptoms. The most common life-threatening concern with DVT is the potential for a clot to embolize (detach from the veins), travel as an embolus through the right side of the heart, and become lodged in a pulmonary artery that supplies blood to the lungs. This is called a pulmonary embolism (PE). DVT and PE comprise the cardiovascular disease of venous thromboembolism (VTE). About two-thirds of VTE manifests as DVT only, with one-third manifesting as PE with or without DVT. The most frequent long-term DVT complication is post-thrombotic syndrome, which can cause pain, swelling, a sensation of heaviness, itching, and in severe cases, ulcers. Recurrent VTE occurs in about 30% of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coagulation
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism of coagulation involves activation, adhesion and aggregation of platelets, as well as deposition and maturation of fibrin. Coagulation begins almost instantly after an injury to the endothelium lining a blood vessel. Exposure of blood to the subendothelial space initiates two processes: changes in platelets, and the exposure of subendothelial tissue factor to plasma factor VII, which ultimately leads to cross-linked fibrin formation. Platelets immediately form a plug at the site of injury; this is called ''primary hemostasis. Secondary hemostasis'' occurs simultaneously: additional coagulation (clotting) factors beyond factor VII ( listed below) respond in a cascade to form fibrin strands, which strengthen the platelet plug. Disorders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heparin
Heparin, also known as unfractionated heparin (UFH), is a medication and naturally occurring glycosaminoglycan. Since heparins depend on the activity of antithrombin, they are considered anticoagulants. Specifically it is also used in the treatment of heart attacks and unstable angina. It is given intravenously or by injection under the skin. Other uses for its anticoagulant properties include inside blood specimen test tubes and kidney dialysis machines. Common side effects include bleeding, pain at the injection site, and low blood platelets. Serious side effects include heparin-induced thrombocytopenia. Greater care is needed in those with poor kidney function. Heparin is contraindicated for suspected cases of vaccine-induced pro-thrombotic immune thrombocytopenia (VIPIT) secondary to SARS-CoV-2 vaccination, as heparin may further increase the risk of bleeding in an anti-PF4/heparin complex autoimmune manner, in favor of alternative anticoagulant medications (such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stroke
A stroke is a disease, medical condition in which poor cerebral circulation, blood flow to the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemorrhagic, due to bleeding. Both cause parts of the brain to stop functioning properly. Signs and symptoms of a stroke may include an hemiplegia, inability to move or feel on one side of the body, receptive aphasia, problems understanding or expressive aphasia, speaking, dizziness, or Homonymous hemianopsia, loss of vision to one side. Signs and symptoms often appear soon after the stroke has occurred. If symptoms last less than one or two hours, the stroke is a transient ischemic attack (TIA), also called a mini-stroke. A subarachnoid hemorrhage, hemorrhagic stroke may also be associated with a thunderclap headache, severe headache. The symptoms of a stroke can be permanent. Long-term complications may include pneumonia and Urinary incontin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombosis
Thrombosis (from Ancient Greek "clotting") is the formation of a 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 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 venous thrombus can break off as an embolus, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypercoagulable
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 ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematophagy
Hematophagy (sometimes spelled haematophagy or hematophagia) is the practice by certain animals of feeding on blood (from the Greek words αἷμα ' "blood" and φαγεῖν ' "to eat"). Since blood is a fluid tissue rich in nutritious proteins and lipids that can be taken without great effort, hematophagy is a preferred form of feeding for many small animals, such as worms and arthropods. Some intestinal nematodes, such as Ancylostomatids, feed on blood extracted from the capillaries of the gut, and about 75 percent of all species of leeches (e.g., ''Hirudo medicinalis'') are hematophagous. The spider Evarcha culicivora feeds indirectly on vertebrate blood by specializing on blood-filled female mosquitoes as their preferred prey. Some fish, such as lampreys and candirus, and mammals, especially the vampire bats, and birds, such as the vampire finches, hood mockingbirds, the Tristan thrush, and oxpeckers also practise hematophagy. Mechanism and evolution These hematop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiplatelet Drug
An antiplatelet drug (antiaggregant), also known as a platelet agglutination inhibitor or platelet aggregation inhibitor, is a member of a class of pharmaceuticals that decrease platelet aggregation and inhibit thrombus formation. They are effective in the arterial circulation where anticoagulants have little effect. They are widely used in primary and secondary prevention of thrombotic cerebrovascular or cardiovascular disease. Antiplatelet therapy with one or more of these drugs decreases the ability of blood clots to form by interfering with the platelet activation process in primary hemostasis. Antiplatelet drugs can reversibly or irreversibly inhibit the process involved in platelet activation resulting in decreased tendency of platelets to adhere to one another and to damaged blood vessels' endothelium. Choice A 2006 review states: "...low-dose aspirin increases the risk of major bleeding 2-fold compared with placebo. However, the annual incidence of major bleeding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombolytic
Thrombolysis, also called fibrinolytic therapy, is the breakdown (lysis) of blood clots formed in blood vessels, using medication. It is used in ST elevation myocardial infarction, stroke, and in cases of severe venous thromboembolism (massive pulmonary embolism or extensive deep vein thrombosis). The main complication is bleeding (which can be dangerous), and in some situations thrombolysis may therefore be unsuitable. Thrombolysis can also play an important part in reperfusion therapy that deals specifically with blocked arteries. Medical uses Diseases where thrombolysis is used: * ST elevation myocardial infarction: Large trials have shown that mortality can be reduced using thrombolysis (particularly fibrinolysis) in treating heart attacks. It works by stimulating secondary fibrinolysis by plasmin through infusion of analogs of tissue plasminogen activator (tPA), the protein that normally activates plasmin. * Stroke: Thrombolysis reduces major disability or death wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Substance
A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., without breaking chemical bonds. Chemical substances can be simple substances (substances consisting of a single chemical element), chemical compounds, or alloys. Chemical substances are often called 'pure' to set them apart from mixtures. A common example of a chemical substance is pure water; it has the same properties and the same ratio of hydrogen to oxygen whether it is isolated from a river or made in a laboratory. Other chemical substances commonly encountered in pure form are diamond (carbon), gold, table salt ( sodium chloride) and refined sugar ( sucrose). However, in practice, no substance is entirely pure, and chemical purity is specified according to the intended use of the chemical. Chemical substances exist as so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
