|
Hirudinida
Leeches are segmented parasitic or predatory worms that comprise the subclass Hirudinea within the phylum Annelida. They are closely related to the oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodies that can lengthen and contract. Both groups are hermaphrodites and have a clitellum, but leeches typically differ from the oligochaetes in having suckers at both ends and ring markings that do not correspond with their internal segmentation. The body is muscular and relatively solid; the coelom, the spacious body cavity found in other annelids, is reduced to small channels. The majority of leeches live in freshwater habitats, while some species can be found in terrestrial or marine environments. The best-known species, such as the medicinal leech, ''Hirudo medicinalis'', are hematophagous, attaching themselves to a host with a sucker and feeding on blood, having first secreted the peptide hirudin to prevent the blood from clotting. The j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helobdella
''Helobdella'' is a genus of leeches in the family Glossiphoniidae, the freshwater jawless leeches. They occur worldwide.Kutschera, U., et al. (2013)Description of a new leech species from North America, ''Helobdella austinensis'' n. sp.(Hirudinea: Glossiphoniidae), with observations on its feeding behaviour.''Zoosyst Evol'' 89(2) 239-46. These are small, flat leeches which do not feed on blood.Siddall, M. E. and E. Borda. (2003)Phylogeny and revision of the leech genus ''Helobdella'' (Glossiphoniidae) based on mitochondrial gene sequences and morphological data and a special consideration of the ''triserialis'' complex.''Zoologica Scripta'' 32(1), 23-33. Several species in this genus are used as model organisms in the study of developmental biology. It has been difficult to define species in this genus without DNA analysis. Like other leeches in this family, some ''Helobdella'' species are polymorphic, coming in different colors and patterns. On the other hand, some uniformly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the sixth and last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the Perm Governorate, region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the Sauropsida, sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hirudin
Hirudin is a naturally occurring peptide in the salivary glands of blood-sucking leeches (such as ''Hirudo medicinalis'') that has a blood anticoagulant property. This is essential for the leeches' habit of feeding on blood, since it keeps a host's blood flowing after the worm's initial puncture of the skin. Hirudin (MEROPS I14.001) belongs to a superfamily (MEROPS IM) of protease inhibitors that also includes haemadin (MEROPS I14.002) and antistasin (MEROPS I15). Structure During his years in Birmingham and Edinburgh, John Berry Haycraft had been actively engaged in research and published papers on the coagulation of blood, and in 1884, he discovered that the leech secreted a powerful anticoagulant, which he named hirudin, although it was not isolated until the 1950s, nor its structure fully determined until 1976. Full length hirudin is made up of 65 amino acids. These amino acids are organized into a compact N-terminal domain containing three disulfide bonds and a C-term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrobiologia
''Hydrobiologia'', ''The International Journal of Aquatic Sciences'', is a peer-reviewed scientific journal publishing 21 issues per year, for a total of well over 4000 pages per year. ''Hydrobiologia'' publishes original research, reviews and opinions investigating the biology of freshwater and marine habitats, including the impact of human activities. Coverage includes molecular-, organism-, community -and ecosystem-level studies dealing with biological research in limnology and oceanography, including systematics and aquatic ecology. In addition to hypothesis-driven experimental research, it presents theoretical papers relevant to a broad hydrobiological audience, and collections of papers in special issues covering focused topics. History ''Hydrobiologia'' changed on the appointment of Henri Dumont to be its editor-in-chief. He introduced peer review, and expanded production from 6 issues per year to more than 20 per year. Koen Martens took over the responsibility as editor-i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haemadipsa Zeylanica Japonica
''Haemadipsa'' is a genus of leeches, with members commonly known as ''jawed land leeches''. These annelids are known from subtropical and tropical regions around the Indian and Pacific Ocean. Well-known ''Haemadipsa'' are for example the Indian Leech (''Haemadipsa sylvestris'') and the yamabiru or Japanese Mountain Leech (''Haemadipsa zeylanica''). Members of the genus feed on blood. They are troublesome to humans and animals especially because their bites result in prolonged bleeding. Species in the genus ''Haemadipsa'' *'' Haemadipsa cavatuses'' *'' Haemadipsa cochiniana'' *'' Haemadipsa crenata'' *'' Haemadipsa hainana'' *'' Haemadipsa interrupta'' *'' Haemadipsa japonica'' *'' Haemadipsa limuna'' *'' Haemadipsa moorei'' *'' Haemadipsa montana'' *'' Haemadipsa ornata'' *'' Haemadipsa picta'' (Tiger leech) *'' Haemadipsa rjukjuana'' *'' Haemadipsa sumatrana'' *'' Haemadipsa sylvestris'' (Indian leech) *'' Haemadipsa trimaculosa'' *'' Haemadipsa zeylanica'' (Japanese mountain le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merriam-Webster
Merriam-Webster, Incorporated is an list of companies of the United States by state, American company that publishes reference work, reference books and is mostly known for Webster's Dictionary, its dictionaries. It is the oldest dictionary publisher in the United States. In 1831, George Merriam, George and Charles Merriam founded the company as G & C Merriam Co. in Springfield, Massachusetts. In 1843, after Noah Webster died, the company bought the rights to ''Webster's Dictionary#Noah Webster's American Dictionary of the English Language, An American Dictionary of the English Language'' from Webster's estate. All Merriam-Webster dictionaries trace their lineage to this source. In 1964, Encyclopædia Britannica, Inc., acquired Merriam-Webster, Inc., as a subsidiary. The company adopted its current name, Merriam-Webster, Incorporated, in 1982. History 19th century In 1806, Webster published his first dictionary, s:A Compendious Dictionary of the English Language, ''A Compen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greed
Greed (or avarice, ) is an insatiable desire for material gain (be it food, money, land, or animate/inanimate possessions) or social value, such as status or power. Nature of greed The initial motivation for (or purpose of) greed and actions associated with it may be the promotion of personal or family survival. It may at the same time be an intent to deny or obstruct competitors from potential means (for basic survival and comfort) or future opportunities; therefore being insidious or tyrannical and having a negative connotation. Alternately, the purpose could be defense or counteractive response to such obstructions being threatened by others. Modern economic thought frequently distinguishes ''greed'' from ''self-interest'', even in its earliest works, and spends considerable effort distinguishing the line between the two. By the mid-19th century – affected by the phenomenological ideas of Hegel – economic and political thinkers began to define greed inherent t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Book Of Proverbs
The Book of Proverbs (, ; , ; , "Proverbs (of Solomon)") is a book in the third section (called Ketuvim) of the Hebrew Bible (Tanakh)/the Christian Old Testament. It is traditionally ascribed to King Solomon and his students. When translated into Ancient Greek, Greek and Latin, the title took on different forms: in the Greek Septuagint (LXX), it became (, "Proverbs"); in the Latin Vulgate, the title was —from which the English name is derived. Proverbs is not merely an anthology but a "collection of collections" relating to a pattern of life that lasted for more than a millennium. It is an example of Biblical wisdom literature and raises questions about values, moral behavior, the meaning of human life, and right conduct, and its Theology, theological foundation is that "the fear of God is the beginning of wisdom." Wisdom (personification), Wisdom is personified and praised for her role in creation; God created her before all else and gave order to chaos through her. As humans ... [...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] |
Microsurgery
Microsurgery is a general term for surgery requiring an operating microscope. The most obvious developments have been procedures developed to allow anastomosis of successively smaller blood vessels and nerves (typically 1 mm in diameter) which have allowed transfer of tissue from one part of the body to another and re-attachment of severed parts. Microsurgical techniques are utilized by several specialties today, such as general surgery, ophthalmology, orthopedic surgery, gynecological surgery, otolaryngology, neurosurgery, oral and maxillofacial surgery, endodontic microsurgery, plastic surgery, podiatric surgery and pediatric surgery. History Otolaryngologists were the first physicians to use microsurgical techniques. A Swedish otolaryngologist, Carl-Olof Siggesson Nylén (1892–1978), was the father of microsurgery. In 1921, in the University of Stockholm, he built the first surgical microscope, a modified monocular Brinell-Leitz microscope. At first he used it f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epicondylitis
Epicondylitis is the inflammation of an epicondyle or of adjacent tissues. Epicondyles are on the medial and lateral aspects of the elbow, consisting of the two bony prominences at the distal end of the humerus. These bony projections serve as the attachment point for the forearm musculature. Inflammation to the tendons and muscles at these attachment points can lead to medial and/or lateral epicondylitis. This can occur through a range of factors that overuse the muscles that attach to the epicondyles, such as sports or job-related duties that increase the workload of the forearm musculature and place stress on the elbow. Lateral epicondylitis is also known as “Tennis Elbow” due to its sports related association to tennis athletes, while medial epicondylitis is often referred to as “golfer's elbow.” Risk factors * In a cross-sectional population-based study among the working population, it was found that psychological distress and bending and straightening of the elbow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
