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Valsalva
The Valsalva maneuver is performed by a forceful attempt of exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut while expelling air out as if blowing up a balloon. Variations of the maneuver can be used either in medical examination as a test of cardiac function and autonomic nervous control of the heart, or to clear the ears and sinuses (that is, to equalize pressure between them) when ambient pressure changes, as in scuba diving, hyperbaric oxygen therapy, or air travel. A modified version is done by expiring against a closed glottis. This will elicit the cardiovascular responses described below but will not force air into the Eustachian tubes. History The technique is named after Antonio Maria Valsalva, a 17th-century physician and anatomist from Bologna whose principal scientific interest was the human ear. He described the Eustachian tube and the maneuver to test its patency (openness). He also described the use of thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antonio Maria Valsalva
Antonio Maria Valsalva (17 January 1666 – 2 February 1723), was an Italian anatomist born in Imola. His research focused on the anatomy of the ears. He coined the term Eustachian tube and he described the aortic sinuses of Valsalva in his writings, published posthumously in 1740. His name is associated with the Valsalva antrum of the ear and the Valsalva maneuver, which is used as a test of circulatory function. Anatomical structures bearing his name are ''Valsalva’s muscle'' and ''taeniae Valsalvae''. He observed that when weakness of one side of the body is caused by a lesion in the brain, the culprit lesion tends to be on the side opposite (contralateral) to the weak side; this finding is named the "Valsalva doctrine" in his honor. Background Valsalva was born at Imola. The contemporary of Isaac Newton and Johann Sebastian Bach, he was educated in the humanities, mathematics, and natural sciences. After studies of the liberal arts, he studied medicine and philosophy i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eustachian Tube
In anatomy, the Eustachian tube, also known as the auditory tube or pharyngotympanic tube, is a tube that links the nasopharynx to the middle ear, of which it is also a part. In adult humans, the Eustachian tube is approximately long and in diameter. It is named after the sixteenth-century Italian anatomist Bartolomeo Eustachi. In humans and other tetrapods, both the middle ear and the ear canal are normally filled with air. Unlike the air of the ear canal, however, the air of the middle ear is not in direct contact with the atmosphere outside the body; thus, a pressure difference can develop between the atmospheric pressure of the ear canal and the middle ear. Normally, the Eustachian tube is collapsed, but it gapes open with swallowing and with positive pressure, allowing the middle ear's pressure to adjust to the atmospheric pressure. When taking off in an aircraft, the ambient air pressure goes from higher (on the ground) to lower (in the sky). The air in the middle ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperbaric Oxygen Therapy
Hyperbaric medicine is medical treatment in which an ambient pressure greater than sea level atmospheric pressure is a necessary component. The treatment comprises hyperbaric oxygen therapy (HBOT), the medical use of oxygen at an ambient pressure higher than atmospheric pressure, and therapeutic recompression for decompression illness, intended to reduce the injurious effects of systemic gas bubbles by physically reducing their size and providing improved conditions for elimination of bubbles and excess dissolved gas. The equipment required for hyperbaric oxygen treatment consists of a pressure chamber, which may be of rigid or flexible construction, and a means of delivering 100% oxygen. Operation is performed to a predetermined schedule by trained personnel who monitor the patient and may adjust the schedule as required. HBOT found early use in the treatment of decompression sickness, and has also shown great effectiveness in treating conditions such as gas gangrene and carbon mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aorta
The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes oxygenated blood to all parts of the body through the systemic circulation. Structure Sections In anatomical sources, the aorta is usually divided into sections. One way of classifying a part of the aorta is by anatomical compartment, where the thoracic aorta (or thoracic portion of the aorta) runs from the heart to the diaphragm. The aorta then continues downward as the abdominal aorta (or abdominal portion of the aorta) from the diaphragm to the aortic bifurcation. Another system divides the aorta with respect to its course and the direction of blood flow. In this system, the aorta starts as the ascending aorta, travels superiorly from the heart, and then makes a hairpin turn known as the aortic arch. Following the aortic arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otoscope
An otoscope or auriscope is a medical device which is used to look into the ears. Health care providers use otoscopes to screen for illness during regular check-ups and also to investigate ear symptoms. An otoscope potentially gives a view of the ear canal and tympanic membrane or eardrum. Because the eardrum is the border separating the external ear canal from the middle ear, its characteristics can be indicative of various diseases of the middle ear space. The presence of earwax (cerumen), shed skin, pus, canal skin edema, foreign body, and various ear diseases can obscure any view of the eardrum and thus severely compromise the value of otoscopy done with a common otoscope, but confirm the presence of obstructing symptoms. The most commonly used otoscopes consist of a handle and a head. The head contains a light source and a simple low-power magnifying lens, typically around 8 diopters (3.00x Mag). The distal (front) end of the otoscope has an attachment for disposabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxillary Molar
The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth", from ''mola'', millstone and ''dens'', tooth. Molars show a great deal of diversity in size and shape across mammal groups. The third molar of humans is sometimes vestigial. Human anatomy In humans, the molar teeth have either four or five cusps. Adult humans have 12 molars, in four groups of three at the back of the mouth. The third, rearmost molar in each group is called a wisdom tooth. It is the last tooth to appear, breaking through the front of the gum at about the age of 20, although this varies from individual to individual. Race can also affect the age at which this occurs, with statistical variations between groups. In some cases, it may not even erupt at all. The human mouth contains upper (maxillary) and lower (mandibu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perforation
A perforation is a small hole in a thin material or web. There is usually more than one perforation in an organized fashion, where all of the holes collectively are called a ''perforation''. The process of creating perforations is called perforating, which involves puncturing the workpiece with a tool. Perforations are usually used to allow easy separation of two sections of the material, such as allowing paper to be torn easily along the line. Packaging with perforations in paperboard or plastic film is easy for consumers to open. Other purposes include filtrating fluids, sound deadening, allowing light or fluids to pass through, and to create an aesthetic design. Various applications include plastic films to allow the packages to breathe, medical films, micro perforated plate and sound and vapor barriers. Processes Pins and needles Rotary pinned perforation rollers are precision tools that can be used to perforate a wide variety of materials. The pins or needles can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antral Communication
A dental extraction (also referred to as tooth extraction, exodontia, exodontics, or informally, tooth pulling) is the removal of teeth from the dental alveolus (socket) in the alveolar bone. Extractions are performed for a wide variety of reasons, but most commonly to remove teeth which have become unrestorable through tooth decay, periodontal disease, or dental trauma, especially when they are associated with toothache. Sometimes impacted wisdom teeth (wisdom teeth that are stuck and unable to grow normally into the mouth) cause recurrent infections of the gum (pericoronitis), and may be removed when other conservative treatments have failed (cleaning, antibiotics and operculectomy). In orthodontics, if the teeth are crowded, healthy teeth may be extracted (often bicuspids) to create space so the rest of the teeth can be straightened. Procedure Extractions could be categorized into non-surgical (simple) and surgical, depending on the type of tooth to be removed and other fact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caisson (engineering)
In geotechnical engineering, a caisson ( or ; borrowed from French ''caisson'', from Italian ''cassone'', meaning ''large box'', an augmentative of ''cassa'') is a watertight retaining structure used, for example, to work on the foundations of a bridge pier, for the construction of a concrete dam, or for the repair of ships. Caissons are constructed in such a way that the water can be pumped out, keeping the work environment dry. When piers are being built using an open caisson, and it is not practical to reach suitable soil, friction pilings may be driven to form a suitable sub-foundation. These piles are connected by a foundation pad upon which the column pier is erected. Caisson engineering has been used at least since the 18th century, and was notably used in the construction of the Brooklyn Bridge, which was completed in 1883. Types To install a caisson in place, it is brought down through soft mud until a suitable foundation material is encountered. While bedrock is pref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swallowing
Swallowing, sometimes called deglutition in scientific contexts, is the process in the human or animal body that allows for a substance to pass from the mouth, to the pharynx, and into the esophagus, while shutting the epiglottis. Swallowing is an important part of eating and drinking. If the process fails and the material (such as food, drink, or medicine) goes through the trachea, then choking or pulmonary aspiration can occur. In the human body the automatic temporary closing of the epiglottis is controlled by the swallowing reflex. The portion of food, drink, or other material that will move through the neck in one swallow is called a bolus. In colloquial English, the term "swallowing" is also used to describe the action of taking in a large mouthful of food without any biting, where the word gulping is more adequate. In humans Swallowing comes so easily to most people that the process rarely prompts much thought. However, from the viewpoints of physiology, of speechâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Pacific Underwater Medicine Society Journal
The South Pacific Underwater Medicine Society (SPUMS) is a primary source of information for diving and hyperbaric medicine physiology worldwide. History The SPUMS was founded on May 3, 1971 in the wardroom of HMAS PENGUIN. The founding members of SPUMS were Carl Edmonds, Bob Thomas, Douglas Walker, Ian Unsworth, and Cedric Deal and they were joined by approximately 20 others as "charter members". The society was incorporated in 1990. Purpose The aims of SPUMS have never changed since its inception: * To promote and facilitate the study of all aspects of underwater and hyperbaric medicine; * To provide information on underwater and hyperbaric medicine; * To publish a journal and; * To convene members of each Society annually at a scientific conference. Training SPUMS offers a Diploma of Diving and Hyperbaric Medicine. This certification, was the first non-naval certification and for years the only postgraduate education available. The first Diplomas by examination were awa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yawn
A yawn is a reflex lasting 4-7 seconds, and is characterized by a long inspiratory phase with gradual mouth gaping, followed by a brief climax (or acme) with muscle stretching, and a rapid expiratory phase with muscle relaxation. For fish and birds, this is described as gradual mouth gaping, staying open for at least 3 seconds and subsequently a rapid closure of the mouth. Almost all vertebrate animals, including mammals, birds, reptiles, amphibians, and even fish, experience yawning. The study of yawning is called chasmology. Yawning (oscitation) most often occurs in adults immediately before and after sleep, during tedious activities and as a result of its contagious quality. It is commonly associated with tiredness, stress, sleepiness, boredom, or even hunger. In humans, yawning is often triggered by the perception that others are yawning (for example, seeing a person yawning, or talking to someone on the phone who is yawning). This is a typical example of positive feedb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
