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Eimeria Stiedae
''Eimeria stiedae'' is a species of ''Eimeria'' that causes hepatic coccidiosis in rabbits. It was observed for the first time by Antonie van Leeuwenhoek in 1674. Life cycle The rabbits ingest sporulated oocysts. Sporulated oocysts contain sporozoites that hatch and travel via the hepatic portal vein to the liver, and eventually penetrate the bile duct epithelium, where they undergo asexual reproduction known as schizogony. Rupture of the schizont consequently causes epithelial cell rupture and death. Merozoites will penetrate other cells and create more merozoites for one to several rounds. Eventually, a merozoite becomes a male microgamecyte and asexually reproduces in epithelial cells. A ruptured microgamecyte infects a cell with the female macrogamecyte and through sexual reproduction create a zygote. The zygote develops a protective shell before expulsion in the bile excreation and then the feces as an oocyst. Pathogenesis and pathology The schizonts in the bile duct cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eimeria
''Eimeria'' is a genus of apicomplexan parasites that includes various species capable of causing the disease coccidiosis in animals such as cattle, poultry and smaller ruminants including sheep and goats. ''Eimeria'' species are considered to be monoxenous because the life cycle is completed within a single host, and stenoxenous because they tend to be host specific, although a number of exceptions have been identified. Species of this genus infect a wide variety of hosts. Thirty-one species are known to occur in bats (Chiroptera), two in turtles, and 130 named species infect fish. Two species (''E. phocae'' and ''E. weddelli'') infect seals. Five species infect llamas and alpacas: ''E. alpacae'', ''E. ivitaensis'', ''E. lamae'', ''E. macusaniensis'', and ''E. punonensis''. A number of species infect rodents, including ''E. couesii'', ''E. kinsellai'', ''E. palustris'', ''E. ojastii'' and ''E. oryzomysi''. Others infect poultry (''E. necatrix'' and ''E. tenella''), rabbits ('' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizogony
Fission, in biology, is the division of a single entity into two or more parts and the regeneration of those parts to separate entities resembling the original. The object experiencing fission is usually a cell, but the term may also refer to how organisms, bodies, populations, or species split into discrete parts. The fission may be ''binary fission'', in which a single organism produces two parts, or ''multiple fission'', in which a single entity produces multiple parts. Binary fission Organisms in the domains of Archaea and Bacteria reproduce with binary fission. This form of asexual reproduction and cell division is also used by some organelles within eukaryotic organisms (e.g., mitochondria). Binary fission results in the reproduction of a living prokaryotic cell (or organelle) by dividing the cell into two parts, each with the potential to grow to the size of the original. Fission of prokaryotes The single DNA molecule first replicates, then attaches each copy to a dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1674 In Science
The year 1674 in science and technology involved some significant events. Biology * Antonie van Leeuwenhoek discovers infusoria using the microscope. Pharmacology * Thomas Willis publishes ''Pharmaceutice rationalis''. Births * Deaths * Jean Pecquet, French anatomist (born 1622 Events January–May * January 7 – The Holy Roman Empire and Transylvania sign the Peace of Nikolsburg. * February 8 – King James I of England dissolves the Parliament of England, English Parliament. * March 12 – ...) References 17th century in science 1670s in science {{year-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conoidasida
Conoidasida is a class of parasitic alveolates in the phylum Apicomplexa. The class was defined in 1988 by Levine and contains two subclasses – the coccidia and the gregarines. All members of this class have a complete, hollow, truncated conoid. Gregarines tend to parasitize invertebrates with the mature gamonts being extracellular; the coccidia mostly infect vertebrates and have intracellular gamonts. Description A conoid is found in most species and when present forms complete but truncated cone. Sexual and asexual reproduction are present in life cycle of all species. Each zygote normally forms an oocyst wall within which it undergoes meiosis. This is sometimes followed by mitosis. This process of sporogony produces mobile vermiform infectious sporozoites. Multiple mitotic divisions ( schizogony) also occur during merogony of the feeding stages (trophozoites) and during gametogony. Motility Microgametes of some species are flagellated. Locomotion of other gam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jaundice
Jaundice, also known as icterus, is a yellowish or, less frequently, greenish pigmentation of the skin and sclera due to high bilirubin levels. Jaundice in adults is typically a sign indicating the presence of underlying diseases involving abnormal heme metabolism, liver dysfunction, or biliary-tract obstruction. The prevalence of jaundice in adults is rare, while jaundice in babies is common, with an estimated 80% affected during their first week of life. The most commonly associated symptoms of jaundice are itchiness, pale feces, and dark urine. Normal levels of bilirubin in blood are below 1.0 mg/ dl (17 μmol/ L), while levels over 2–3 mg/dl (34–51 μmol/L) typically result in jaundice. High blood bilirubin is divided into two types: unconjugated and conjugated bilirubin. Causes of jaundice vary from relatively benign to potentially fatal. High unconjugated bilirubin may be due to excess red blood cell breakdown, large bruises, gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatomegaly
Hepatomegaly is enlargement of the liver. It is a non-specific sign (medicine), medical sign, having many causes, which can broadly be broken down into infection, hepatic tumours, and metabolic disorder. Often, hepatomegaly presents as an abdominal mass. Depending on the cause, it may sometimes present along with jaundice. Signs and symptoms The patient may experience many symptoms, including weight loss, poor appetite, and lethargy; jaundice and bruising may also be present. Causes Among the causes of hepatomegaly are the following: Infective Mechanism The mechanism of hepatomegaly consists of Blood vessel, vascular swelling, inflammation (infectious in origin), and deposition of (1) non-hepatic cells or (2) increased cell contents (such as that due to iron in hemochromatosis or hemosiderosis and fat in fatty liver disease). Diagnosis Suspicion of hepatomegaly indicates a thorough medical history and Abdominal examination, physical examination, wherein the latter typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperplasia
Hyperplasia (from ancient Greek ὑπέρ ''huper'' 'over' + πλάσις ''plasis'' 'formation'), or hypergenesis, is an enlargement of an organ or tissue caused by an increase in the amount of Tissue (biology), organic tissue that results from cell proliferation. It may lead to the Gross anatomy, gross enlargement of an organ, and the term is sometimes confused with benign neoplasia or benign tumor. Hyperplasia is a common preneoplastic response to stimulus. Microscopically, cells resemble normal cells but are increased in numbers. Sometimes cells may also be increased in size (hypertrophy). Hyperplasia is different from hypertrophy in that the Cellular adaptation, adaptive cell change in hypertrophy is an increase in the cell size, ''size'' of cells, whereas hyperplasia involves an increase in the ''number'' of cells. Causes Hyperplasia may be due to any number of causes, including proliferation of basal layer of epidermis to compensate skin loss, Chronic inflammation, chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygote
A zygote (; , ) is a eukaryote, eukaryotic cell (biology), cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. The sexual fusion of haploid cells is called karyogamy, the result of which is the formation of a Ploidy#Haploid and monoploid, diploid cell called the zygote or zygospore. History German zoologists Oscar Hertwig, Oscar and Richard Hertwig made some of the first discoveries on animal zygote formation in the late 19th century. In multicellular organisms The zygote is the earliest developmental stage. In humans and most other Anisogamy, anisogamous organisms, a zygote is formed when an egg cell and sperm, sperm cell come together to create a new unique organism. The formation of a cell potency, totipotent zygote with the potential to produce a whole organism depends on epigenetics, epigenetic reprogramming. DNA demethyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelium
Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of many internal organs, the corresponding inner surfaces of body cavities, and the inner surfaces of blood vessels. Epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. These tissues also lack blood or lymph supply. The tissue is supplied by nerves. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. These can be arranged in a singular layer of cells as simple epithelium, either simple squamous, simple columnar, or simple cuboidal, or in layers of two or more cells deep as stratified (layered), or ''compound'', either squamous, columnar or cuboidal. In some tissues, a layer of columnar cells may appear to be stratified d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccidiosis
Coccidiosis is a parasitic disease of the intestinal tract of animals caused by coccidian protozoa. The disease spreads from one animal to another by contact with infected feces or ingestion of infected tissue. Diarrhea, which may become bloody in severe cases, is the primary symptom. Most animals infected with coccidia are asymptomatic, but young or immunocompromised animals may suffer severe symptoms and death. While coccidia can infect a wide variety of animals, including humans, birds, and livestock, they are usually species-specific. One well-known exception is toxoplasmosis caused by '' Toxoplasma gondii''. Humans may first encounter coccidia when they acquire a dog, cat or bird that is infected. Other than ''T. gondii'', the infectious organisms are canine and feline-specific and are not contagious to humans, unlike the zoonotic diseases. Coccidia in dogs Puppies are frequently infected with coccidia from the feces of their mother, and are more likely to develop cocc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bile Duct
A bile duct is any of a number of long tube-like structures that carry bile, and is present in most vertebrates. The bile duct is separated into three main parts: the fundus (superior), the body (middle), and the neck (inferior). Bile is required for the digestion of food and is secreted by the liver into passages that carry bile toward the hepatic duct. It joins the cystic duct (carrying bile to and from the gallbladder) to form the common bile duct which then opens into the intestine. Structure The top half of the common bile duct is associated with the liver, while the bottom half of the common bile duct is associated with the pancreas, through which it passes on its way to the intestine. It opens into the part of the intestine called the duodenum via the ampulla of Vater. Segments The biliary tree (see below) is the whole network of various sized ducts branching through the liver. The path is as follows: bile canaliculi → canals of Hering → interlobular bil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatic Portal Vein
The portal vein or hepatic portal vein (HPV) is a blood vessel that carries blood from the gastrointestinal tract, gallbladder, pancreas and spleen to the liver. This blood contains nutrients and toxins extracted from digested contents. Approximately 75% of total liver blood flow is through the portal vein, with the remainder coming from the hepatic artery proper. The blood leaves the liver to the heart in the hepatic veins. The portal vein is not a true vein, because it conducts blood to capillary beds in the liver and not directly to the heart. It is a major component of the hepatic portal system, one of three portal venous systems in the human body; the others being the hypophyseal and renal portal systems. The portal vein is usually formed by the confluence of the superior mesenteric, splenic veins, inferior mesenteric, left, right gastric veins and the pancreatic vein. Conditions involving the portal vein cause considerable illness and death. An important e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
