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Atractaspis Engaddensis
''Atractaspis engaddensis'', also known as "שרף עין גדי" (in Hebrew, pronounced "Saraf Ein Gedi") or "الأسود الخبيث" (in Arabic, pronounced "al'aswad alkhabith") is a venomous snake found in Egypt (Sinai Peninsula), Israel, Jordan, Lebanon, and Saudi Arabia. The specific epithet references the type locality, Ein Gedi on the western shore of the Dead Sea. Description It is an extremely venomous and a dangerous snake native to the Middle East. Its body is usually dark black in color and it has small eyes with round pupils. The head and the tail are short and pointy which makes it harder even for veterans to distinguish head from tail. Its approximate size is 60–80 cm. This snake's fangs are able to be directed outside of its mouth, granting it the ability to side stab with a closed mouth. Feeding They prefer hatchling snakes but they can also eat small mammals like young rodents. Venom "Three isotoxins, named sarafotoxins S6a1, S6b and S6c, with st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Haas (zoologist)
Georg Haas (19 January 1905, Vienna, Austria – 13 September 1981 Jerusalem, Israel) was an Austrian-born Israeli herpetologist, malacologist and paleontologist, one of the founders of zoological research in Israel. Haas studied zoology in the University of Vienna. In 1932 he joined the Hebrew University staff and during the next four decades Haas influenced several generations of young Israeli scientists. Legacy Georg Haas is commemorated in the scientific names of two species of lizards, ''Acanthodactylus haasi'' and ''Sphenomorphus, Sphenomorphus haasi'',Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . ("Haas, G.", p. 113). and the ''Cretaceous'' legged basal snake ''Haasiophis''. References Further reading *Yehudah L. Werner, Werner YL (1965). "Georg Haas: On the occasion of his sixtieth birthday". ''Israel Journal of Zoology'' 14 (1–4): 5–6. *Werner YL (198 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarafotoxin
Sarafotoxins (SRTXs) are a group of toxins present in the venom of ''Atractaspis engaddensis'', and in clinical trials cause similar symptoms to patients diagnosed with acute giardiasis. Together with endothelins (ETs), they form a homogenous family of strong vasoconstrictor isopeptides. Among them, a few slightly different substances can be named as SRTX-a, SRTX-b, SRTX-c, which were initially derived from ''Atractaspis engaddensis''. Each one contains twenty-one amino acid residues that spontaneously fold into a defined tertiary structure, with two interchain-cysteine linkages ( disulfide bonds) and a long hydrophobic tail. There are also other compounds, however, they are mostly derivations of previously mentioned ones. The main differences in the family of endothelin and sarafotoxins appear at N-terminal of peptides, as C-terminal in all of them is almost the same. History In 1989, a few months after reporting the discovery and describing structure of endothelin, the se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of Jordan
The wildlife of Jordan includes its flora and fauna and their natural habitats. Although much of the country is desert, it has several geographic regions, each with a diversity of plants and animals adapted to their own particular habitats. Fossil finds show that in Palaeolithic times, the region had Syrian brown bears, Asiatic lions, zebras, Asian elephants, and rhinoceroses, but these species are all now extinct in this region. More recently, in the twentieth century, the Arabian oryx became locally extinct through hunting, and several species of deer and gazelle were reduced to remnant populations. The Royal Society for the Conservation of Nature was established in 1966 to preserve Jordan's natural resources, a number of protected areas have been set up, and conservation measures and captive breeding programs have been put in place, resulting in an increase in the numbers of these animals. In 1978, 11 Arabian Oryx were brought in to Jordan from USA. They were taken care of at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snakes Of Jordan
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads ( cranial kinesis). To accommodate their narrow bodies, snakes' paired organs (such as kidneys) appear one in front of the other instead of side by side, and most have only one functional lung. Some species retain a pelvic girdle with a pair of vestigial claws on either side of the cloaca. Lizards have evolved elongate bodies without limbs or with greatly reduced limbs about twenty-five times independently via convergent evolution, leading to many lineages of legless lizards. These resemble snakes, but several common groups of legless lizards have eyelids and external ears, which snakes lack, although this rule is not universal (see Amphisbaenia, Di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Of The Middle East
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians (tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. The earliest known proto-reptiles originated around 31 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Described In 1950
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians (tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. The earliest known proto-reptiles originated around 31 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atractaspididae
The Atractaspididae (atractaspidids) are a family of venomous snakes found in Africa and the Middle East, commonly called mole vipers, stiletto snakes, or burrowing asps. Currently, 12 genera are recognized. Description This family includes many genera formerly classed in other families and subfamilies, on the basis of fang type. It includes fangless ( aglyphous), rear-fanged (opisthoglyphous), fixed-fanged (proteroglyphous), and viper-like (solenoglyphous) species. Early molecular and physiological data linking this subfamily to others were ambiguous and often contradictory, which means the taxonomy of this subfamily has been highly contentious. The nominate family, Atractaspididae, has itself been moved to and from other taxa, such as potentially forming a trichotomy with Elapidae and Colubridae, reinforcing the ambiguity of this subfamily. Geographic range This subfamily is found in Africa and the Middle East.Mehrtens JM. 1987. Living Snakes of the World in Color. New York: St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atrioventricular Block
Atrioventricular block (AV block) is a type of heart block that occurs when the electrical signal traveling from the atria, or the upper chambers of the heart, to ventricles, or the lower chambers of the heart, is impaired. Normally, the sinoatrial node (SA node) produces an electrical signal to control the heart rate. The signal travels from the SA node to the ventricles through the atrioventricular node (AV node). In an AV block, this electrical signal is either delayed or completely blocked. When the signal is completely blocked, the ventricles produce their own electrical signal to control the heart rate. The heart rate produced by the ventricles is much slower than that produced by the SA node. Some AV blocks are benign, or normal, in certain people, such as in athletes or children. Other blocks are pathologic, or abnormal, and have several causes, including ischemia, infarction, fibrosis, and drugs. __TOC__ Classification There are three types, or degrees, of AV block: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a toxin, radiation, or pathogen. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of increased toxicity. The test was created by J.W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug Botox without animal tests. Conventions The LD50 is usually expressed as the mass of substance administered per unit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A polypeptide is a longer, continuous, unbranched peptide chain. Hence, peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. A polypeptide that contains more than approximately 50 amino acids is known as a protein. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiotoxic
Cardiotoxicity is the occurrence of heart dysfunction as electric or muscle damage, resulting in heart toxicity. The heart becomes weaker and is not as efficient in pumping blood. Cardiotoxicity may be caused by chemotherapy (a usual example is the class of anthracyclines) treatment and/or radiotherapy; complications from anorexia nervosa; adverse effects of heavy metals intake; the long-term abuse of or ingestion at high doses of certain strong stimulants such as cocaine; or an incorrectly administered drug such as bupivacaine. One of the ways to detect cardiotoxicity at early stages when there is a subclinical dysfunction is by measuring changes in regional function of the heart using strains. See also * Cardiotoxin III * Batrachotoxin * Heart failure * Drug interaction Drug interactions occur when a drug's mechanism of action is disturbed by the concomitant administration of substances such as foods, beverages, or other drugs. The cause is often the inhibition of the speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dead Sea
The Dead Sea ( he, יַם הַמֶּלַח, ''Yam hamMelaḥ''; ar, اَلْبَحْرُ الْمَيْتُ, ''Āl-Baḥrū l-Maytū''), also known by other names, is a salt lake bordered by Jordan to the east and Israel and the West Bank to the west. It lies in the Jordan Rift Valley, and its main tributary is the Jordan River. As of 2019, the lake's surface is below sea level, making its shores the lowest land-based elevation on Earth. It is deep, the deepest hypersaline lake in the world. With a salinity of 342 g/kg, or 34.2% (in 2011), it is one of the world's saltiest bodies of water – 9.6 times as salty as the ocean – and has a density of 1.24 kg/litre, which makes swimming similar to floating. This salinity makes for a harsh environment in which plants and animals cannot flourish, hence its name. The Dead Sea's main, northern basin is long and wide at its widest point. The Dead Sea has attracted visitors from around the Mediterranean Basin for th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
