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Coccygeal Glomus
The coccygeal glomus (coccygeal gland or body; Luschka’s gland) is a vestigial structure placed in front of, or immediately below, the tip of the coccyx. Anatomy It is about 2.5 mm. in diameter and is irregularly oval in shape; several smaller nodules are found around or near the main mass. It consists of irregular masses of round or polyhedral cells epitheloid cells, which are grouped around a dilated sinusoidal capillary vessel. Each cell contains a large round or oval nucleus, the protoplasm surrounding which is clear, and is not stained by chromic salts. Since it is not stained by chromic salts, it is not truly a part of Chromafin system; viz. the system which includes cells stained by chromic salts, consisting of renal medulla, para ganglia, and para aortic bodies. It is situated near the ganglion impar in pelvis, and also at the termination of median sacral artery. Clinical significance It may appear similar to a glomus tumor :''Glomus tumor was also the name f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Median Sacral Artery
The median sacral artery (or middle sacral artery) is a small artery that arises posterior to the abdominal aorta and superior to its bifurcation. Structure The median sacral artery arises from the abdominal aorta at the level of the bottom quarter of the third lumbar vertebra. It descends in the middle line in front of the fourth and fifth lumbar vertebrae, the sacrum and coccyx, ending in the glomus coccygeum (coccygeal gland). Minute branches pass from it, to the posterior surface of the rectum. On the last lumbar vertebra it anastomoses with the lumbar branch of the iliolumbar artery; in front of the sacrum it anastomoses with the lateral sacral arteries, sending offshoots into the anterior sacral foramina. It is crossed by the left common iliac vein and accompanied by a pair of venae comitantes; these unite to form a single vessel that opens into the left common iliac vein. Development The median sacral artery is morphologically the direct continuation of the abdom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubert Von Luschka
Hubert is a Germanic masculine given name, from ''hug'' "mind" and ''beraht'' "bright". It also occurs as a surname. Saint Hubertus or Hubert (c. 656 – 30 May 727) is the patron saint of hunters, mathematicians, opticians, and metalworkers. People with the given name Hubert This is a small selection of articles on people named Hubert; for a comprehensive list see instead . *Hubert Aaronson (1924–2005), F. Mehl University Professor at Carnegie Mellon University * Hubert Adair (1917–1940), World War II Royal Air Force pilot *Hubert Boulard, a French comics creator who is unusually credited as "Hubert" * Hubert Brasier (1917–1981), a Church of England clergyman, more famously the father of UK Prime Minister Theresa May * Hubert Buchanan (born 1941), a United States Air Force captain and fighter pilot *Hubert Chevis (1902–1931), a lieutenant in the Royal Artillery of the British Army who died of strychnine poisoning in June 1931 * Hubert Davies, British playwright and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestigiality
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 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 positive selection pressures when it loses its value in a changing environment. The feature may be 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 organs) are the loss of functional wings in island-dwelling birds; the human vomeronasal organ; and the hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccyx
The coccyx ( : coccyges or coccyxes), commonly referred to as the tailbone, is the final segment of the vertebral column in all apes, and analogous structures in certain other mammals such as horses. In tailless primates (e.g. humans and other great apes) since ''Nacholapithecus'' (a Miocene hominoid),Nakatsukasa 2004, ''Acquisition of bipedalism'' (SeFig. 5entitled ''First coccygeal/caudal vertebra in short-tailed or tailless primates.''.) the coccyx is the remnant of a vestigial tail. In animals with bony tails, it is known as ''tailhead'' or ''dock'', in bird anatomy as ''tailfan''. It comprises three to five separate or fused coccygeal vertebrae below the sacrum, attached to the sacrum by a fibrocartilaginous joint, the sacrococcygeal symphysis, which permits limited movement between the sacrum and the coccyx. Structure The coccyx is formed of three, four or five rudimentary vertebrae. It articulates superiorly with the sacrum. In each of the first three segments may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinusoid (blood Vessel)
A capillary is a small blood vessel from 5 to 10 micrometres (μm) in diameter. Capillaries are composed of only the tunica intima, consisting of a thin wall of simple squamous endothelial cells. They are the smallest blood vessels in the body: they convey blood between the arterioles and venules. These microvessels are the site of exchange of many substances with the interstitial fluid surrounding them. Substances which cross capillaries include water, oxygen, carbon dioxide, urea, glucose, uric acid, lactic acid and creatinine. Lymph capillaries connect with larger lymph vessels to drain lymphatic fluid collected in the microcirculation. During early embryonic development, new capillaries are formed through vasculogenesis, the process of blood vessel formation that occurs through a '' de novo'' production of endothelial cells that then form vascular tubes. The term ''angiogenesis'' denotes the formation of new capillaries from pre-existing blood vessels and already present endo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoplasm
Protoplasm (; ) is the living part of a cell that is surrounded by a plasma membrane. It is a mixture of small molecules such as ions, monosaccharides, amino acid, and macromolecules such as proteins, polysaccharides, lipids, etc. In some definitions, it is a general term for the cytoplasm (e.g., Mohl, 1846), but for others, it also includes the nucleoplasm (e.g., Strasburger, 1882). For Sharp (1921), "According to the older usage the extra-nuclear portion of the protoplast 'the entire cell, excluding the cell wall''was called "protoplasm," but the nucleus also is composed of protoplasm, or living substance in its broader sense. The current consensus is to avoid this ambiguity by employing Strasburger's '(1882)''terms cytoplasm Albert_von_Kölliker.html"_;"title="'coined_by_Albert_von_Kölliker">Kölliker_(1863),_originally_as_synonym_for_protoplasm''and_nucleoplasm_([''term_coined_by_Edouard_Van_Beneden.html" ;"title="Albert von Kölliker">Kölliker (1863), originally as syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromium
Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium metal is valued for its high corrosion resistance and hardness. A major development in steel production was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. Stainless steel and chrome plating (electroplating with chromium) together comprise 85% of the commercial use. Chromium is also greatly valued as a metal that is able to be highly polished while resisting tarnishing. Polished chromium reflects almost 70% of the visible spectrum, and almost 90% of infrared light. The name of the element is derived from the Greek word χρῶμα, ''chrōma'', meaning color, because many chromium compounds are intensely colored. Industrial production of chromium proceeds from chromite ore (mostly FeCr2O4) to produce ferro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glomus Tumor
:''Glomus tumor was also the name formerly (and incorrectly) used for a tumor now called a paraganglioma.'' A glomus tumor (also known as a "solitary glomus tumor," "solid glomus tumor,") is a rare neoplasm arising from the glomus body and mainly found under the nail, on the fingertip or in the foot.Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. . They account for less than 2% of all soft tissue tumors. The majority of glomus tumors are benign, but they can also show malignant features. Glomus tumors were first described by Hoyer in 1877 while the first complete clinical description was given by Masson in 1924. Histologically, glomus tumors are made up of an afferent arteriole, anastomotic vessel, and collecting venule. Glomus tumors are modified smooth muscle cells that control the thermoregulatory function of dermal glomus bodies. As stated above, these lesions should not be confused with paragangliomas, which were formerly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
