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Adenoid
In anatomy, the pharyngeal tonsil, also known as the nasopharyngeal tonsil or adenoid, is the superior-most of the tonsils. It is a mass of lymphoid tissue located behind the nasal cavity, in the roof and the posterior wall of the nasopharynx, where the nose blends into the throat. In children, it normally forms a soft mound in the roof and back wall of the nasopharynx, just above and behind the uvula. The term ''adenoid'' is also used to represent adenoid hypertrophy, the abnormal growth of the pharyngeal tonsils. Structure The adenoid is a mass of lymphoid tissue located behind the nasal cavity, in the roof and the posterior wall of the nasopharynx, where the nose blends into the throat. The adenoid, unlike the palatine tonsils, has pseudostratified epithelium. The adenoids are part of the so-called Waldeyer ring of lymphoid tissue which also includes the palatine tonsils, the lingual tonsils and the tubal tonsils. Development Adenoids develop from a subepithelia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenoid Hypertrophy
Adenoid hypertrophy, also known as enlarged adenoids refers to an enlargement of the adenoid (pharyngeal tonsil) that is linked to nasopharyngeal mechanical blockage and/or chronic inflammation. Adenoid hypertrophy is a characterized by hearing loss, recurrent otitis media, mucopurulent rhinorrhea, chronic mouth breathing, nasal airway obstruction, increased infection susceptibility, dental malposition and dentofacial abnormalities ("adenoid facies" or "mouth breather face"). The exact cause of adenoid hypertrophy in children remains unclear, but it is likely linked to immunological responses, hormonal factors, or genetic components. Adenoid hypertrophy is an immunological abnormality characterized by altered cytokine production, with children experiencing higher levels of proinflammatory cytokines. Adenoid hypertrophy can also be caused by gastric juice exposure during gastroesophageal reflux disease, passive smoking, and recurrent bacterial and viral infections. Pathogen coloni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonsil
The tonsils ( ) are a set of lymphoid organs facing into the aerodigestive tract, which is known as Waldeyer's tonsillar ring and consists of the adenoid tonsil (or pharyngeal tonsil), two tubal tonsils, two palatine tonsils, and the lingual tonsils. These organs play an important role in the immune system. When used unqualified, the term most commonly refers specifically to the palatine tonsils, which are two lymphoid organs situated at either side of the back of the human throat. The palatine tonsils and the adenoid tonsil are organs consisting of lymphoepithelial tissue located near the oropharynx and nasopharynx (parts of the throat). Structure Humans are born with four types of tonsils: the pharyngeal tonsil, two tubal tonsils, two palatine tonsils and the lingual tonsils. Development The palatine tonsils tend to reach their largest size in puberty, and they gradually undergo atrophy thereafter. However, they are largest relative to the diameter of the throat in youn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palatine Tonsil
Palatine tonsils, commonly called the tonsils and occasionally called the faucial tonsils, are tonsils located on the left and right sides at the back of the throat in humans and other mammals, which can often be seen as flesh-colored, pinkish lumps. Tonsils only present as "white lumps" if they are inflamed or infected with symptoms of exudates (pus drainage) and severe swelling. Tonsillitis is an inflammation of the tonsils and will often, but not necessarily, cause a sore throat and fever. In chronic cases, tonsillectomy may be indicated. Structure The palatine tonsils are located in the isthmus of the fauces, between the palatoglossal arch and the palatopharyngeal arch of the soft palate. The palatine tonsil is one of the mucosa-associated lymphoid tissues (MALT), located at the entrance to the upper respiratory and gastrointestinal tracts to protect the body from the entry of exogenous material through mucosal sites. In consequence it is a site of, and potentia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waldeyer's Tonsillar Ring
Waldeyer's tonsillar ring (pharyngeal lymphoid ring, Waldeyer's lymphatic ring, or tonsillar ring) is a ringed arrangement of lymphoid organs in the pharynx. Waldeyer's ring surrounds the naso- and oropharynx, with some of its tonsillar tissue located above and some below the soft palate (and to the back of the mouth cavity). Structure The ring consists of the (from top to bottom): * 1 pharyngeal tonsil (or "adenoid"), located on the roof of the nasopharynx, under the sphenoid bone. * 2 tubal tonsils on each side, where each auditory tube opens into the nasopharynx * 2 palatine tonsils (commonly called "the tonsils") located in the oropharynx * lingual tonsils, a collection of lymphatic tissue located on the back part of the tongue Terminology Some authors speak of two pharyngeal tonsils/two adenoids. These authors simply look at the left and right halves of the pharyngeal tonsil as two tonsils. Many authors also speak of lingual tonsils (in the plural), because this accumulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphatic Tissues
The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphoid organs, lymphatic tissue and lymph. Lymph is a clear fluid carried by the lymphatic vessels back to the heart for re-circulation. The Latin word for lymph, , refers to the deity of fresh water, "Lympha". Unlike the circulatory system that is a closed system, the lymphatic system is open. The human circulatory system processes an average of 20 litres of blood per day through capillary filtration, which removes plasma from the blood. Roughly 17 litres of the filtered blood is reabsorbed directly into the blood vessels, while the remaining three litres are left in the interstitial fluid. One of the main functions of the lymphatic system is to provide an accessory return route to the blood for the surplus three litres. The other main function is that of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasopharynx
The pharynx (: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates, though its structure varies across species. The pharynx carries food to the esophagus and air to the larynx. The flap of cartilage called the epiglottis stops food from entering the larynx. In humans, the pharynx is part of the digestive system and the conducting zone of the respiratory system. (The conducting zone—which also includes the nostrils of the nose, the larynx, trachea, bronchi, and bronchioles—filters, warms, and moistens air and conducts it into the lungs). The human pharynx is conventionally divided into three sections: the nasopharynx, oropharynx, and laryngopharynx (hypopharynx). In humans, two sets of pharyngeal muscles form the pharynx and determine the shape of its lumen. They are arranged as an inner layer of longitudina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Throat
In vertebrate anatomy, the throat is the front part of the neck, internally positioned in front of the vertebrae. It contains the Human pharynx, pharynx and larynx. An important section of it is the epiglottis, separating the esophagus from the trachea (windpipe), preventing food and drinks being inhaled into the lungs. The throat contains various blood vessels, pharyngeal muscles, the adenoid, nasopharyngeal tonsil, the tonsils, the palatine uvula, the trachea, the esophagus, and the vocal cords. Mammal throats consist of two bones, the hyoid bone and the clavicle. The "throat" is sometimes thought to be synonymous for the Fauces (throat), fauces. It works with the mouth, ears and nose, as well as a number of other parts of the body. Its pharynx is connected to the mouth, allowing speech to occur, and food and liquid to pass down the throat. It is joined to the nose by the nasopharynx at the top of the throat, and to the ear by its Eustachian tube. The throat's trachea carries in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubal Tonsils
The tubal tonsil, also known as Gerlach tonsil, is one of the four main tonsil groups forming Waldeyer's tonsillar ring. Structure Each tubal tonsil is located posterior to the opening of the Eustachian tube on the lateral wall of the nasopharynx. It is one of the four main tonsil groups forming Waldeyer's tonsillar ring. This ring also includes the palatine tonsils, the lingual tonsils, and the adenoid. Clinical significance The tubal tonsil may be affected by tonsillitis. However, this usually affects only the palatine tonsils. History The tubal tonsil may also be known as the Gerlach tonsil. It is very close to the torus tubarius The torus tubarius (or torus of the auditory tube) is an elevation of the mucous membrane of the Pharynx#Nasopharynx, nasal part of the pharynx formed by the underlying base of the Eustachian tube, cartilaginous portion of the Eustachian tube, Eu ..., which is why this tonsil is sometimes also called the ''tonsil of (the) torus tubarius''.E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomy
Anatomy () is the branch of morphology concerned with the study of the internal structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times. Anatomy is inherently tied to developmental biology, embryology, comparative anatomy, evolutionary biology, and phylogeny, as these are the processes by which anatomy is generated, both over immediate and long-term timescales. Anatomy and physiology, which study the structure and function of organisms and their parts respectively, make a natural pair of related disciplines, and are often studied together. Human anatomy is one of the essential basic sciences that are applied in medicine, and is often studied alongside physiology. Anatomy is a complex and dynamic field that is constantly evolving as discoveries are made. In recent years, there has been a significant increase in the use of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nocardia
''Nocardia'' is a genus of weakly staining Gram-positive, catalase, catalase-positive, rod-shaped bacteria. It forms partially acid-fast beaded branching filaments (appearing similar to fungi, but being truly bacteria). It contains a total of 85 species. Some species are nonpathogenic, while others are responsible for nocardiosis. ''Nocardia'' species are found worldwide in soil rich in organic matter. In addition, they are oral microflora found in healthy human Gums, gingiva, as well as periodontal pockets. Most ''Nocardia'' infections are acquired by inhalation of the bacteria or through traumatic introduction through openings in Epithelium, epithelial barriers. Culture and staining ''Nocardia'' colonies have a variable appearance, but most species appear to have aerial hyphae when viewed with a dissecting microscope, particularly when they have been grown on nutritionally limiting media. ''Nocardia'' grow slowly on nonselective culture media, and are strict Aerobic metaboli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-hemolytic Streptococci
''Streptococcus'' is a genus of gram-positive spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. Cell division in streptococci occurs along a single axis, thus when growing they tend to form pairs or chains, which may appear bent or twisted. This differs from staphylococci, which divide along multiple axes, thereby generating irregular, grape-like clusters of cells. Most streptococci are oxidase-negative and catalase-negative, and many are facultative anaerobes (capable of growth both aerobically and anaerobically). The term was coined in 1877 by Viennese surgeon Albert Theodor Billroth (1829–1894), by combining the prefix "strepto-" (from ), together with the suffix "-coccus" (from Modern , from .) In 1984, many bacteria formerly grouped in the genus ''Streptococcus'' were separated out into the genera ''Enterococcus'' and ''Lactococcus''. Currently, over 50 species are recognis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterococci
''Enterococcus'' is a large genus of lactic acid bacteria of the phylum Bacillota. Enterococci are Gram-positive cocci that often occur in pairs (diplococci) or short chains, and are difficult to distinguish from streptococci on physical characteristics alone. Two species are common commensal organisms in the intestines of humans: '' E. faecalis'' (90–95%) and '' E. faecium'' (5–10%). Rare clusters of infections occur with other species, including '' E. durans'' , ''E. casseliflavus'', '' E. gallinarum'', and ''E. raffinosus''. Physiology and classification Enterococci are facultative anaerobic organisms, i.e., they are capable of cellular respiration in both oxygen-rich and oxygen-poor environments. Though they are not capable of forming spores, enterococci are tolerant of a wide range of environmental conditions: extreme temperature (10–45 °C), pH (4.6–9.9), and high sodium chloride concentrations. ''E. faecium'' and ''E. faecalis'' can be differentiated bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
