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Immunity (medical)
In biology, immunity is the state of being insusceptible or resistant to a noxious agent or process, especially a pathogen or infectious disease. Immunity may occur naturally or be produced by prior exposure or immunization. Innate and adaptive The immune system has innate and adaptive components. Innate immunity is present in all metazoans, immune responses: inflammatory responses and phagocytosis. The adaptive component, on the other hand, involves more advanced lymphatic cells that can distinguish between specific "non-self" substances in the presence of "self". The reaction to foreign substances is etymologically described as inflammation while the non-reaction to self substances is described as immunity. The two components of the immune system create a dynamic biological environment where "health" can be seen as a physical state where the self is immunologically spared, and what is foreign is inflammatorily and immunologically eliminated. "Disease" can arise when what is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biology
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary information encoded in genes, which can be transmitted to future generations. Another major theme is evolution, which explains the unity and diversity of life. Energy processing is also important to life as it allows organisms to move, grow, and reproduce. Finally, all organisms are able to regulate their own internal environments. Biologists are able to study life at multiple levels of organization, from the molecular biology of a cell to the anatomy and physiology of plants and animals, and evolution of populations.Based on definition from: Hence, there are multiple subdisciplines within biology, each defined by the nature of their research questions and the tools that they use. Like other scientists, biologists use the sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunological Memory
Immunological memory is the ability of the immune system to quickly and specifically recognize an antigen that the body has previously encountered and initiate a corresponding immune response. Generally, these are secondary, tertiary and other subsequent immune responses to the same antigen. The adaptive immune system and antigen-specific receptor generation ( TCR, antibodies) are responsible for adaptive immune memory. After the inflammatory immune response to danger-associated antigen, some of the antigen-specific T cells and B cells persist in the body and become long-living memory T and B cells. After the second encounter with the same antigen, they recognize the antigen and mount a faster and more robust response. Immunological memory is the basis of vaccination.Hammarlund, Erika, et al. (2003). "Duration of antiviral immunity after smallpox vaccination." Nature medicine 9.9, 1131. Emerging resources show that even the innate immune system can initiate a more efficient immune ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proximate Causation
A proximate cause is an event which is ''closest'' to, or immediately responsible for causing, some observed result. This exists in contrast to a higher-level ultimate cause (or ''distal cause'') which is usually thought of as the "real" reason something occurred. * ''Example:'' Why did the ship sink? ** Proximate cause: Because it was holed beneath the waterline, water entered the hull and the ship became denser than the water which supported it, so it could not stay afloat. ** Ultimate cause: Because the ship hit a rock which tore open the hole in the ship's hull. In most situations, an ultimate cause may itself be a proximate cause in comparison to a further ultimate cause. Hence we can continue the above example as follows: * ''Example:'' Why did the ship hit the rock? ** Proximate cause: Because the ship failed to change course to avoid it. ** Ultimate cause: Because the ship was under autopilot and the autopilot's data was inaccurate. ** (even stronger): Because the ship ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaccine
A vaccine is a biological Dosage form, preparation that provides active acquired immunity to a particular infectious disease, infectious or cancer, malignant disease. The safety and effectiveness of vaccines has been widely studied and verified. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or Antigen, killed forms of the microbe, its toxins, or one of its surface proteins. The agent stimulates the body's immune system to recognize the agent as a threat, destroy it, and to further recognize and destroy any of the microorganisms associated with that agent that it may encounter in the future. Vaccines can be prophylaxis, prophylactic (to prevent or ameliorate the effects of a future infection by a natural or "wild" pathogen), or therapeutic vaccines, therapeutic (to fight a disease that has already occurred, such as cancer vaccine, cancer). [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxoid
A toxoid is an inactivated toxin (usually an exotoxin) whose toxicity has been suppressed either by chemical (formalin) or heat treatment, while other properties, typically immunogenicity, are maintained. Toxins are secreted by bacteria, whereas toxoids are altered form of toxins; toxoids are ''not'' secreted by bacteria. Thus, when used during vaccination, an immune response is mounted and immunological memory is formed against the molecular markers of the toxoid without resulting in toxin-induced illness. Such a preparation is also known as an anatoxin. There are toxoids for prevention of diphtheria, tetanus and botulism. Toxoids are used as vaccines because they induce an immune response to the original toxin or increase the response to another antigen since the toxoid markers and toxin markers are preserved. For example, the tetanus toxoid is derived from the tetanospasmin produced by ''Clostridium tetani''. The latter causes tetanus and is vaccinated against by the DTaP vac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mithridates VI Of Pontus
Mithridates or Mithradates VI Eupator ( grc-gre, Μιθραδάτης; 135–63 BC) was ruler of the Kingdom of Pontus in northern Anatolia from 120 to 63 BC, and one of the Roman Republic's most formidable and determined opponents. He was an effective, ambitious and ruthless ruler who sought to dominate Asia Minor and the Black Sea region, waging several hard-fought but ultimately unsuccessful wars (the Mithridatic Wars) to break Roman dominion over Asia and the Hellenic world. He has been called the greatest ruler of the Kingdom of Pontus. He cultivated an immunity to poisons by regularly ingesting sub-lethal doses; this practice, now called mithridatism, is named after him. After his death he became known as Mithridates the Great. Etymology ''Mithridates'' is the Greek attestation of the Persian name ''Mihrdāt'', meaning "given by Mithra", the name of the ancient Iranian sun god. The name itself is derived from Old Iranian ''Miθra-dāta-''. Ancestry, family and early lif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Athens
Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates and is the capital of the Attica region and is one of the world's oldest cities, with its recorded history spanning over 3,400 years and its earliest human presence beginning somewhere between the 11th and 7th millennia BC. Classical Athens was a powerful city-state. It was a centre for the arts, learning and philosophy, and the home of Plato's Academy and Aristotle's Lyceum. It is widely referred to as the cradle of Western civilization and the birthplace of democracy, largely because of its cultural and political influence on the European continent—particularly Ancient Rome. In modern times, Athens is a large cosmopolitan metropolis and central to economic, financial, industrial, maritime, political and cultural life in Gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thucydides
Thucydides (; grc, , }; BC) was an Athenian historian and general. His ''History of the Peloponnesian War'' recounts the fifth-century BC war between Sparta and Athens until the year 411 BC. Thucydides has been dubbed the father of "scientific history" by those who accept his claims to have applied strict standards of impartiality and evidence-gathering and analysis of cause and effect, without reference to intervention by the gods, as outlined in his introduction to his work. He also has been called the father of the school of political realism, which views the political behavior of individuals and the subsequent outcomes of relations between states as ultimately mediated by, and constructed upon, fear and self-interest. His text is still studied at universities and military colleges worldwide. The Melian dialogue is regarded as a seminal work of international relations theory, while his version of Pericles' Funeral Oration is widely studied by political theorists, historian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Four Humors
Humorism, the humoral theory, or humoralism, was a system of medicine detailing a supposed makeup and workings of the human body, adopted by Ancient Greek and Roman physicians and philosophers. Humorism began to fall out of favor in the 1850s with the advent of germ theory, which was able to show that many diseases previously thought to be humoral were in fact caused by microbes. Origin The concept of "humors" (chemical systems regulating human behaviour) became more prominent from the writing of medical theorist Alcmaeon of Croton (c. 540–500 BC). His list of humors was longer and included fundamental elements described by Empedocles, such as water, air, earth, fire, etc.. The concept of "humors" may have origins in Ancient Egyptian medicine, or Mesopotamia, though it was not systemized until ancient Greek thinkers. The word ''humor'' is a translation of Greek χυμός, ''chymos'' (literally juice or sap, metaphorically flavor). Ancient Indian Ayurveda medicine had deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocrates
Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history of medicine. He is traditionally referred to as the "Father of Medicine" in recognition of his lasting contributions to the field, such as the use of prognosis and clinical observation, the systematic categorization of diseases, or the formulation of humoral theory. The Hippocratic school of medicine revolutionized ancient Greek medicine, establishing it as a discipline distinct from other fields with which it had traditionally been associated (theurgy and philosophy), thus establishing medicine as a profession. However, the achievements of the writers of the Hippocratic Corpus, the practitioners of Hippocratic medicine, and the actions of Hippocrates himself were often conflated; thus very little is known about what Hippocrates actually t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theurgy
Theurgy (; ) describes the practice of rituals, sometimes seen as magical in nature, performed with the intention of invoking the action or evoking the presence of one or more deities, especially with the goal of achieving henosis (uniting with the divine) and perfecting oneself. Definitions *Proclus (c. 480): theurgy is "a power higher than all human wisdom embracing the blessings of divination, the purifying powers of initiation and in a word all the operations of divine possession" * Keith Thomas: "Spiritual magic or theurgy was based on the idea that one could reach God in an ascent up the scale of creation made possible by a rigorous course of prayer, fasting and devotional preparation." * Pierre A. Riffard: "Theurgy is a type of magic. It consists of a set of magical practices performed to evoke beneficent spirits in order to see them or know them or in order to influence them, for instance by forcing them to animate a statue, to inhabit a human being (such as a mediu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholera Art
Cholera is an infection of the small intestine by some strains of the bacterium '' Vibrio cholerae''. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea that lasts a few days. Vomiting and muscle cramps may also occur. Diarrhea can be so severe that it leads within hours to severe dehydration and electrolyte imbalance. This may result in sunken eyes, cold skin, decreased skin elasticity, and wrinkling of the hands and feet. Dehydration can cause the skin to turn bluish. Symptoms start two hours to five days after exposure. Cholera is caused by a number of types of ''Vibrio cholerae'', with some types producing more severe disease than others. It is spread mostly by unsafe water and unsafe food that has been contaminated with human feces containing the bacteria. Undercooked shellfish is a common source. Humans are the only known host for the bacteria. Risk factors for the disease include poor sanitation, not en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
