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Bühler's Anastomotic Artery
In human anatomy, Bühler's anastomotic artery (also called the arc of Bühler) is a rare anastomotic shunt joining the superior mesenteric artery and the celiac trunk in vertical orientation. As these arteries arise separately from different levels of the abdominal aorta, the shunt provides limited collateral circulation should a blockage occur in the intervening arterial segment. Bühler's artery is a rare phenomenon present in up to 3% of the population, and is thought to be an unobliterated remnant of the ventral longitudinal anastomosis present during embryological development Prenatal development () involves the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal deve .... References {{DEFAULTSORT:Buhler'S anaStomotic Artery Arteries Abdomen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Anatomy
Human anatomy (gr. ἀνατομία, "dissection", from ἀνά, "up", and τέμνειν, "cut") is primarily the scientific study of the morphology of the human body. Anatomy is subdivided into gross anatomy and microscopic anatomy. Gross anatomy (also called macroscopic anatomy, topographical anatomy, regional anatomy, or anthropotomy) is the study of anatomical structures that can be seen by the naked eye. Microscopic anatomy is the study of minute anatomical structures assisted with microscopes, which includes histology (the study of the organization of tissues), and cytology (the study of cells). Anatomy, human physiology (the study of function), and biochemistry (the study of the chemistry of living structures) are complementary basic medical sciences that are generally together (or in tandem) to students studying medical sciences. In some of its facets human anatomy is closely related to embryology, comparative anatomy and comparative embryology, through common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anastomosis
An anastomosis (, : anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf veins, or streams. Such a connection may be normal (such as the foramen ovale in a fetus' heart) or abnormal (such as the patent foramen ovale in an adult's heart); it may be acquired (such as an arteriovenous fistula) or innate (such as the arteriovenous shunt of a metarteriole); and it may be natural (such as the aforementioned examples) or artificial (such as a surgical anastomosis). The reestablishment of an anastomosis that had become blocked is called a reanastomosis. Anastomoses that are abnormal, whether congenital or acquired, are often called fistulas. The term is used in medicine, biology, mycology, geology, and geography. Etymology Anastomosis: medical or Modern Latin, from Greek ἀναστόμωσις, anastomosis, "outlet, opening", Greek ana- "up, on, upon", stoma "mouth" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Mesenteric Artery
In human anatomy, the superior mesenteric artery (SMA) is an artery which arises from the anterior surface of the abdominal aorta, just inferior to the origin of the celiac trunk, and supplies blood to the intestine from the lower part of the duodenum through two-thirds of the transverse colon, as well as the pancreas. Structure Origin In the adult, the SMA arises anterior to inferior border of vertebra L1 ( transpyloric plane). It is usually 1 cm lower than the celiac trunk. Course and relations It initially travels in an anterior/inferior direction, passing behind/under the neck of the pancreas and the splenic vein. Located under this portion of the superior mesenteric artery, between it and the aorta, are the following: * left renal vein - travels between the left kidney and the inferior vena cava (can be compressed between the SMA and the abdominal aorta at this location, leading to nutcracker syndrome). * the third part of the duodenum, a segment of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celiac Trunk
The celiac () artery (also spelled coeliac in British English), also known as the celiac trunk or truncus coeliacus, is the first major branch of the abdominal aorta. It is about 1.25 cm in length. Branching from the aorta at thoracic vertebra 12 (T12) in humans, it is one of three anterior/ midline branches of the abdominal aorta (the others are the superior and inferior mesenteric arteries). Structure The celiac artery is the first major branch of the descending abdominal aorta, branching at a 90° angle. This occurs just below the crus of the diaphragm. This is around the first lumbar vertebra. There are three main divisions of the celiac artery, and each in turn has its own named branches: The celiac artery may also give rise to the inferior phrenic arteries. Function The celiac artery supplies oxygenated blood to the liver, stomach, abdominal esophagus, spleen, and the superior half of both the duodenum and the pancreas. These structures correspond to the em ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abdominal Aorta
In human anatomy, the abdominal aorta is the largest artery in the abdominal cavity. As part of the aorta, it is a direct continuation of the descending aorta (of the thorax). Structure The abdominal aorta begins at the level of the diaphragm, crossing it via the aortic hiatus, technically behind the diaphragm, at the vertebral level of T12. It travels down the posterior wall of the abdomen, anterior to the vertebral column. It thus follows the curvature of the lumbar vertebrae, that is, convex anteriorly. The peak of this convexity is at the level of the third lumbar vertebra (L3). It runs parallel to the inferior vena cava, which is located just to the right of the abdominal aorta, and becomes smaller in diameter as it gives off branches. This is thought to be due to the large size of its principal branches. At the 11th rib, the diameter is 122mm long and 55mm wide and this is because of the constant pressure. The abdominal aorta is clinically divided into 2 segments: # Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestigial Structure
Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on comparison with homology (biology), homologous features in related species. The emergence of vestigiality occurs by normal evolutionary processes, typically by loss of function of a feature that is no longer subject to Directional selection, positive Evolutionary pressure, selection pressures when it loses its value in a changing environment. The feature may be Negative selection (natural selection), selected against more urgently when its function becomes definitively harmful, but if the lack of the feature provides no advantage, and its presence provides no disadvantage, the feature may not be phased out by natural selection and persist across species. Examples of vestigial structures (also called degenerate, atrophied, or rudimentary orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryological Development
Prenatal development () involves the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal development until birth. The term "prenate" is used to describe an unborn offspring at any stage of gestation. In human pregnancy, prenatal development is also called antenatal development. The development of the human embryo follows fertilization, and continues as fetal development. By the end of the tenth week of gestational age, the embryo has acquired its basic form and is referred to as a fetus. The next period is that of fetal development where many organs become fully developed. This fetal period is described both topically (by organ) and chronologically (by time) with major occurrences being listed by gestational age. The very early stages of embryonic development are the same in all mammals, but later stages of development, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteries
An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in the pulmonary circulation that carry blood to the lungs for oxygenation, and the umbilical arteries in the fetal circulation that carry deoxygenated blood to the placenta. It consists of a multi-layered artery wall wrapped into a tube-shaped channel. Arteries contrast with veins, which carry deoxygenated blood back towards the heart; or in the pulmonary and fetal circulations carry oxygenated blood to the lungs and fetus respectively. Structure The anatomy of arteries can be separated into gross anatomy, at the macroscopic scale, macroscopic level, and histology, microanatomy, which must be studied with a microscope. The arterial system of the human body is divided into systemic circulation, systemic arteries, carrying blood from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
