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Alexander Schmidt (physiologist)
Hermann Adolf Alexander Schmidt ( – ) was a Baltic German physiologist from what was then the Governorate of Livonia in the Russian Empire. He was born on the island of Moon, which is today known by its Estonian name Muhu, in present-day Estonia. In 1858, he received his medical doctorate from the University of Dorpat, and later was an assistant to Felix Hoppe-Seyler (1825-1895) in Berlin, and to Carl Ludwig (1816-1895) in Leipzig. In 1869 he succeeded Friedrich Bidder (1810-1894) as professor of physiology at Dorpat, where he remained for the rest of his life. From 1885 to 1889 he served as university rector. Schmidt is remembered for his research involving the process of blood coagulation by demonstrating that the transformation of fibrinogen into fibrin was the result of an enzymatic process. He named the hypothetical enzyme "thrombin", and he called its precursor "prothrombin". Schmidt is credited for providing a foundation for the creation of anti-coagulation systems ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liiva, Muhu Parish
Liiva is a village on the Estonian island Muhu. (retrieved 28 July 2021) It is the administrative centre of Muhu Parish in Saare County and also is the largest village in the municipality with a population of 189 (as of 1 January 2012). Liiva is situated in the heart of the island by the main road (segment of the Risti–Kuressaare road, nr 10). Liiva is the location of the Early Gothic Muhu St. Catherine's Church from the 13th century. Not far from the church there is a rectory from 1832, where a famous physiologist, founder of the 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 ... theory Alexander Schmidt was born. Liiva is home to the Muhu Primary School with about 100 pupils. There's also a library, supermarket (Konsum), post office and a pharmacy in the villa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felix Hoppe-Seyler
Ernst Felix Immanuel Hoppe-Seyler (''né'' Felix Hoppe; 26 December 1825 – 10 August 1895) was a German physiologist and chemist, and the principal founder of the disciplines of biochemistry and molecular biology. Biography Hoppe-Seyler was born in Freyburg an der Unstrut in the Province of Saxony. He originally trained to be a physician in Halle and Leipzig, and received his medical doctorate from Berlin in 1851. Afterwards, he was an assistant to Rudolf Virchow at the Pathological Institute in Berlin. Hoppe-Seyler preferred scientific research to medicine, and later held positions in anatomy, applied chemistry, and physiological chemistry in Greifswald, Tübingen and Strasbourg. At Strasbourg, he was head of the department of biochemistry, the only such institution in Germany at the time. His work also led to advances in organic chemistry by his students and by immunologist Paul Ehrlich. Among his students and collaborators were Friedrich Miescher (1844–1895) and Nobel l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Transfusion
Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but modern medical practice commonly uses only components of the blood, such as red blood cells, white blood cells, plasma, clotting factors and platelets. Red blood cells (RBC) contain hemoglobin, and supply the cells of the body with oxygen. White blood cells are not commonly used during transfusion, but they are part of the immune system, and also fight infections. Plasma is the "yellowish" liquid part of blood, which acts as a buffer, and contains proteins and important substances needed for the body's overall health. Platelets are involved in blood clotting, preventing the body from bleeding. Before these components were known, doctors believed that blood was homogeneous. Because of this scientific misunderstanding, many patients died ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prothrombin
Thrombin (, ''fibrinogenase'', ''thrombase'', ''thrombofort'', ''topical'', ''thrombin-C'', ''tropostasin'', ''activated blood-coagulation factor II'', ''blood-coagulation factor IIa'', ''factor IIa'', ''E thrombin'', ''beta-thrombin'', ''gamma-thrombin'') is a serine protease, an enzyme that, in humans, is encoded by the ''F2'' gene. Prothrombin (coagulation factor II) is proteolytically cleaved to form thrombin in the clotting process. Thrombin in turn acts as a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, as well as catalyzing many other coagulation-related reactions. History After the description of fibrinogen and fibrin, Alexander Schmidt hypothesised the existence of an enzyme that converts fibrinogen into fibrin in 1872. Prothrombin was discovered by Pekelharing in 1894. Physiology Synthesis Thrombin is produced by the enzymatic cleavage of two sites on prothrombin by activated Factor X (Xa). The activity of factor Xa is gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombin
Thrombin (, ''fibrinogenase'', ''thrombase'', ''thrombofort'', ''topical'', ''thrombin-C'', ''tropostasin'', ''activated blood-coagulation factor II'', ''blood-coagulation factor IIa'', ''factor IIa'', ''E thrombin'', ''beta-thrombin'', ''gamma-thrombin'') is a serine protease, an enzyme that, in humans, is encoded by the ''F2'' gene. Prothrombin (coagulation factor II) is proteolytically cleaved to form thrombin in the clotting process. Thrombin in turn acts as a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, as well as catalyzing many other coagulation-related reactions. History After the description of fibrinogen and fibrin, Alexander Schmidt hypothesised the existence of an enzyme that converts fibrinogen into fibrin in 1872. Prothrombin was discovered by Pekelharing in 1894. Physiology Synthesis Thrombin is produced by the enzymatic cleavage of two sites on prothrombin by activated Factor X (Xa). The activity of factor Xa is great ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrin
Fibrin (also called Factor Ia) is a fibrous, non-globular protein involved in the clotting of blood. It is formed by the action of the protease thrombin on fibrinogen, which causes it to polymerize. The polymerized fibrin, together with platelets, forms a hemostatic plug or clot over a wound site. When the lining of a blood vessel is broken, platelets are attracted, forming a platelet plug. These platelets have thrombin receptors on their surfaces that bind serum thrombin molecules, which in turn convert soluble fibrinogen in the serum into fibrin at the wound site. Fibrin forms long strands of tough insoluble protein that are bound to the platelets. Factor XIII completes the cross-linking of fibrin so that it hardens and contracts. The cross-linked fibrin forms a mesh atop the platelet plug that completes the clot. Fibrin was discovered by Marcello Malpighi in 1666. Role in disease Excessive generation of fibrin due to activation of the coagulation cascade leads to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrinogen
Fibrinogen (factor I) is a glycoprotein complex, produced in the liver, that circulates in the blood of all vertebrates. During tissue and vascular injury, it is converted enzymatically by thrombin to fibrin and then to a fibrin-based blood clot. Fibrin clots function primarily to occlude blood vessels to stop bleeding. Fibrin also binds and reduces the activity of thrombin. This activity, sometimes referred to as antithrombin I, limits clotting. Fibrin also mediates blood platelet and endothelial cell spreading, tissue fibroblast proliferation, capillary tube formation, and angiogenesis and thereby promotes revascularization and wound healing. Reduced and/or dysfunctional fibrinogens occur in various congenital and acquired human fibrinogen-related disorders. These disorders represent a group of rare conditions in which individuals may present with severe episodes of pathological bleeding and thrombosis; these conditions are treated by supplementing blood fibrinogen level ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood 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] |
Who Named It
''Whonamedit?'' is an online English-language dictionary of medical eponyms and the people associated with their identification. Though it is a dictionary, many eponyms and persons are presented in extensive articles with comprehensive bibliographies. The dictionary is hosted in Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of ... and maintained by medical historian Ole Daniel Enersen. References External links * Medical websites Medical dictionaries Eponyms {{online-dict-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rector (academia)
A rector (Latin for 'ruler') is a senior official in an educational institution, and can refer to an official in either a university or a secondary school. Outside the English-speaking world the rector is often the most senior official in a university, whilst in the United States the most senior official is often referred to as president and in the United Kingdom and Commonwealth of Nations the most senior official is the chancellor, whose office is primarily ceremonial and titular. The term and office of a rector can be referred to as a rectorate. The title is used widely in universities in EuropeEuropean nations where the word ''rector'' or a cognate thereof (''rektor'', ''recteur'', etc.) is used in referring to university administrators include Albania, Austria, the Benelux, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Germany, Greece, Hungary, Iceland, Italy, Latvia, Malta, Moldova, North Macedonia, Poland ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Bidder
Georg Friedrich Karl Heinrich Bidder ( – ) was a Baltic German physiologist and anatomist from what was then the Governorate of Livonia in the Russian Empire. In 1834 he received his doctorate from the University of Dorpat, where he became a professor of anatomy (1842), and physiology and pathology (1843). He was a corresponding member (1857) and honorary member (1884) of the Saint Petersburg Academy of Sciences (today Russian Academy of Sciences). He was the president of the Naturalists' Society at the University of Dorpat from 1877 to 1890. Bidder is primarily remembered for his studies of nutrition and gastric physiology. From 1847 to 1852 he performed physiological-chemical studies of digestive juices and metabolism with chemist Carl Ernst Heinrich Schmidt (1822–1894). He also conducted important investigations of the sympathetic nervous system with Alfred Wilhelm Volkmann (1801–1877) and of the spinal cord with Karl Wilhelm von Kupffer (1829–1902). Bidder's na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
