Dissection (from Latin dissecare "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause of death in humans. Less extensive dissection of plants and smaller animals preserved in a formaldehyde solution is typically carried out or demonstrated in biology and natural science classes in middle school and high school, while extensive dissections of cadavers of adults and children, both fresh and preserved are carried out by medical students in medical schools as a part of the teaching in subjects such as anatomy, pathology and forensic medicine. Consequently, dissection is typically conducted in a morgue or in an anatomy lab.
Dissection of a pregnant rat in a biology class
Plant and animal bodies are dissected to analyze the structure and function of its components. Dissection is practised by students in courses of biology, botany, zoology, and veterinary science, and sometimes in arts studies. In medical schools, students dissect human cadavers to learn anatomy.
A key principle in the dissection of human cadavers is the prevention of human disease to the dissector. Prevention of transmission includes the wearing of protective gear, ensuring the environment is clean, dissection technique and pre-dissection tests to specimens for the presence of HIV and Hepatitis viruses. Specimens are dissected in morgues or anatomy labs. When provided, they are evaluated for use as a "fresh" or "prepared" specimen. A "fresh" specimen may be dissected within some days, retaining the characteristics of a living specimen, for the purposes of training. A "prepared" specimen may be preserved in solutions such as formalin and pre-dissected by an experienced anatomist, sometimes with the help of a diener. This preparation is sometimes called prosection.
Most dissection involves the careful isolation and removal of individual organs, called the Virchow technique. An alternative more cumbersome technique involves the removal of the entire organ body, called the Letulle technique. This technique allows a body to be sent to a funeral director without waiting for the sometimes time-consuming dissection of individual organs. The Rokitansky method involves an in situ dissection of the organ block, and the technique of Ghon involves dissection of three separate blocks of organs - the thorax and cervical areas, gastrointestinal and abdominal organs, and urogenital organs. Dissection of individual organs involves accessing the area in which the organ is situated, and systematically removing the anatomical connections of that organ to its surroundings. For example, when removing the heart, connects such as the superior vena cava and inferior vena cava are separated. If pathological connections exist, such as a fibrous pericardium, then this may be deliberately dissected along with the organ.
Human dissections were carried out by the Greek physicians Herophilus of Chalcedon and Erasistratus of Chios in the early part of the third century BC. During this period, the first exploration into full human anatomy was performed rather than a base knowledge gained from 'problem-solution' delving. While there was a deep taboo in Greek culture concerning human dissection, there was at the time a strong push by the Ptolemaic government to build Alexandria into a hub of scientific study. For a time, Roman law forbade dissection and autopsy of the human body, so physicians had to use other cadavers. Galen, for example, dissected the Barbary macaque and other primates, assuming their anatomy was basically the same as that of humans.
The ancient societies that were rooted in India left behind artwork on how to kill animals during a hunt. The images showing how to kill most effectively depending on the game being hunted relay an intimate knowledge of both external and internal anatomy as well as the relative importance of organs. The knowledge was mostly gained through hunters preparing the recently captured prey. Once the roaming lifestyle was no longer necessary it was replaced in part by the civilization that formed in the Indus Valley. Unfortunately, there is little that remains from this time to indicate whether or not dissection occurred, the civilization was lost to the Aryan people migrating.
Early in the history of India (2nd to 3rd century), the Arthashastra described the 4 ways that death can occur and their symptoms: drowning, hanging, strangling, or asphyxiation. According to that source, an autopsy should be performed in any case of untimely demise.
The practice of dissection flourished during the 7th and 8th century. It was under their rule that medical education was standardized. This created a need to better understand human anatomy, so as to have educated surgeons. Dissection was limited by the religious taboo on cutting the human body. This changed the approach taken to accomplish the goal. The process involved the loosening of the tissues in streams of water before the outer layers were sloughed off with soft implements to reach the musculature. To perfect the technique of slicing, the prospective students used gourds and squash. These techniques of dissection gave rise to an advanced understanding of the anatomy and the enabled them to complete procedures used today, such as rhinoplasty.
During medieval times the anatomical teachings from India spread throughout the known world however the practice of dissection was stunted by Islam. The practice of dissection at a university level was not seen again until 1827, when it was performed by the student Pandit Madhusudan Gupta. Through the 1900s, the University teachers had to continually push against the social taboos of dissection, until around 1850 when the universities decided that it was more cost effective to train Indian doctors than bring them in from Britain. Indian medical schools were, however, training female doctors well before those in England.
The current state of dissection in India is deteriorating. The number of hours spent in dissection labs during medical school has decreased substantially over the last twenty years. The future of anatomy education will probably be an elegant mix of traditional methods and integrative computer learning. The use of dissection in early stages of medical training has been shown more effective in the retention of the intended information than their simulated counterparts. However, there is use for the computer-generated experience as review in the later stages. The combination of these methods are intended to strengthen the students understanding and confidence of anatomy, a subject that is infamously difficult to master. There is a growing need for anatomist—seeing as most anatomy labs are taught by graduates hoping to complete degrees in anatomy—to continue the long tradition of anatomy education.
From the beginning of the Islamic faith in 610 A.D., Shari'ah law has applied to a greater or lesser extent within Muslim countries, supported by Islamic scholars such as Al-Ghazali. Islamic physicians such as Ibn Zuhr (Avenzoar) (1091–1161) in Al-Andalus, Saladin's physician Ibn Jumay during the 12th century, Abd el-Latif in Egypt c. 1200, and Ibn al-Nafis in Syria and Egypt in the 13th century may have practiced dissection, but it remains ambiguous whether or not human dissection was practiced. Ibn al-Nafis, a physician and Muslim jurist, suggested that the "precepts of Islamic law have discouraged us from the practice of dissection, along with whatever compassion is in our temperament", indicating that while there was no law against it, it was nevertheless uncommon. Islam dictates that the body be buried as soon as possible, barring religious holidays, and that there be no other means of disposal such as cremation. Prior to the 10th century, dissection was not performed on human cadavers. The book Al-Tasrif, written by Al-Zahrawi in 1000 A.D., details surgical procedure that differed from the previous standards. The book was an educational text of medicine and surgery which included detailed illustrations. It was later translated and took the place of Avicenna's The Canon of Medicine as the primary teaching tool in Europe from the 12th century to the 17th century. There were some that were willing to dissect humans up to the 12th century, for the sake of learning, after which it was forbidden. This attitude remained constant until 1952, when the Islamic School of Jurisprudence in Egypt ruled that "necessity permits the forbidden". This decision allowed for the investigation of questionable deaths by autopsy. In 1982, the decision was made by a fatwa that if it serves justice, autopsy is worth the disadvantages. Though Islam now approves of autopsy, the Islamic public still disapproves. Autopsy is prevalent in most Muslim countries for medical and judicial purposes. In Egypt it holds an important place within the judicial structure, and is taught at all the country's medical universities. In Saudi Arabia, whose law is completely dictated by Shari'ah, autopsy is viewed poorly by the population but can be compelled in criminal cases; human dissection is sometimes found at university level. Autopsy is performed for judicial purposes in Qatar and Tunisia. Human dissection is present in the modern day Islamic world, but is rarely published on due to the religious and social stigma.
Tibetan medicine developed a rather sophisticated knowledge of anatomy, acquired from long-standing experience with human dissection. Tibetans had adopted the practice of sky burial because of the country's hard ground, frozen for most of the year, and the lack of wood for cremation. A sky burial begins with a ritual dissection of the deceased, and is followed by the feeding of the parts to vultures on the hill tops. Over time, Tibetan anatomical knowledge found its way into Ayurveda and to a lesser extent into Chinese medicine.
Throughout the history of Christian Europe, the dissection of human cadavers for medical education has experienced various cycles of legalization and proscription in different countries. Dissection was rare during the Middle Ages, but it was practised, with evidence from at least as early as the 13th century. The practice of autopsy in Medieval Western Europe is "very poorly known" as few surgical texts or conserved human dissections have survived. A modern Jesuit scholar has claimed that the Christian theology contributed significantly to the revival of human dissection and autopsy by providing a new socio-religious and cultural context in which the human cadaver was no longer seen as sacrosanct.
An edict of the 1163 Council of Tours, and an early 14th-century decree of Pope Boniface VIII have mistakenly been identified as prohibiting dissection and autopsy, misunderstanding or extrapolation from these edicts may have contributed to reluctance to perform such procedures.[a] The Middle Ages witnessed the revival of an interest in medical studies, including human dissection and autopsy.
Frederick II (1194-1250), the Holy Roman emperor, ruled that any that were studying to be a physician or a surgeon must attend a human dissection, which would be held no less than every five years. Some European countries began legalizing the dissection of executed criminals for educational purposes in the late 13th and early 14th centuries. Mondino de Luzzi carried out the first recorded public dissection around 1315. At this time, autopsies were carried out by a team consisting of a Lector, who lectured, the Sector, who did the dissection, and the Ostensor who pointed to features of interest.
Vesalius in the 16th century carried out numerous dissections in his extensive anatomical investigations. He was attacked frequently for his disagreement with Galen's opinions on human anatomy. Vesalius was the first to lecture and dissect the cadaver simultaneously.
The Catholic Church is known to have ordered an autopsy on conjoined twins Joana and Melchiora Ballestero in Hispaniola in 1533 to determine whether they shared a soul. They found that there were two distinct hearts, and hence two souls, based on the ancient Greek philosopher Empedocles, who believed the soul resided in the heart.
Human dissection was also practised by Renaissance artists. Though most chose to focus on the external surfaces of the body, some like Michelangelo Buonarotti, Antonio del Pollaiolo, Baccio Bandinelli, and Leonardo da Vinci sought a deeper understanding. However, there were no provisions for artists to obtain cadavers, so they had to resort to unauthorised means, as indeed anatomists sometimes did, such as grave robbing, body snatching, and murder.
Anatomization was sometimes ordered as a form of punishment, as, for example, in 1806 to James Halligan and Dominic Daley after their public hanging in Northampton, Massachusetts.
In modern Europe, dissection is routinely practised in biological research and education, in medical schools, and to determine the cause of death in autopsy. It is generally considered a necessary part of learning and is thus accepted culturally. It sometimes attracts controversy, as when Odense Zoo decided to dissect lion cadavers in public before a "self-selected audience".
In Britain, dissection remained entirely prohibited from the end of the Roman conquest and through the Middle Ages through the 16th century, when a series of royal edicts gave specific groups of physicians and surgeons some limited rights to dissect cadavers. The permission was quite limited: by the mid-18th century, the Royal College of Physicians and Company of Barber-Surgeons were the only two groups permitted to carry out dissections, and had an annual quota of ten cadavers between them. As a result of pressure from anatomists, especially in the rapidly growing medical schools, the Murder Act 1752 allowed the bodies of executed murderers to be dissected for anatomical research and education. By the 19th century this supply of cadavers proved insufficient, as the public medical schools were growing, and the private medical schools lacked legal access to cadavers. A thriving black market arose in cadavers and body parts, leading to the creation of the profession of body snatching, and the infamous Burke and Hare murders in 1828, when 16 people were murdered for their cadavers, to be sold to anatomists. The resulting public outcry led to the passage of the Anatomy Act 1832, which increased the legal supply of cadavers for dissection.
By the 21st century, the availability of interactive computer programs and changing public sentiment led to renewed debate on the use of cadavers in medical education. The Peninsula College of Medicine and Dentistry in the UK, founded in 2000, became the first modern medical school to carry out its anatomy education without dissection.
In the United States, dissection of frogs became common in college biology classes from the 1920's, and were gradually introduced at earlier stages of education. By 1988, some 75 to 80 percent of American high school biology students were participating in a frog dissection, with a trend towards introduction in elementary schools. The frogs are most commonly from the genus Rana. Other popular animals for high-school dissection at the time of that survey were, among vertebrates, fetal pigs, perch, and cats; and among invertebrates, earthworms, grasshoppers, crayfish, and starfish. About six million animals are (2016) dissected each year in United States high schools, not counting medical training and research. Most of these are purchased already dead from slaughterhouses and farms.
Dissection in U.S. high schools became prominent in 1987, when a California student, Jenifer Graham, sued to require her school to let her complete an alternative project. The court ruled that mandatory dissections were permissible, but that Graham could ask to dissect a frog that had died of natural causes rather than one that was killed for the purposes of dissection; the practical impossibility of procuring a frog that had died of natural causes in effect let Graham opt out of the required dissection. The suit gave publicity to anti-dissection advocates. Graham appeared in a 1987 Apple Computer commercial for the virtual-dissection software Operation Frog. The state of California passed a Student's Rights Bill in 1988 requiring that objecting students be allowed to complete alternative projects. Opting out of dissection increased through the 1990s.
In the United States, 17 states[b] along with Washington, D.C. have enacted dissection-choice laws or policies that allow students in primary and secondary education to opt out of dissection. Other states including Arizona, Hawaii, Minnesota, Texas, and Utah have more general policies on opting out on moral, religious, or ethical grounds.
As for the dissection of cadavers in undergraduate and medical school, traditional dissection is supported by professors and students, with some opposition, limiting the availability of dissection. Upper level students who have experienced this method along with their professors agree that "Studying human anatomy with colorful charts is one thing. Using a scalpel and an actual, recently-living person is an entirely different matter."
The way in which cadaveric specimens are obtained differs greatly according to country. In the UK, donation of a cadaver is wholly voluntary. Involuntary donation plays a role in about 20 percent of specimens in the US and almost all specimens donated in some countries such as South Africa and Zimbabwe. Countries that practice involuntary donation may make available the bodies of dead criminals or unclaimed or unidentified bodies for the purposes of dissection. Such practices may lead to a greater proportion of the poor, homeless and social outcasts being involuntarily donated. Cadavers donated in one jurisdiction may also be used for the purposes of dissection in another, whether across states in the US, or imported from other countries, such as with Libya. As an example of how a cadaver is donated voluntarily, a funeral home in conjunction with a voluntary donation program identifies a body who is part of the program. After broaching the subject with relatives in a diplomatic fashion, the body is then transported to a registered facility. The body is tested for the presence of HIV and Hepatitis viruses. It is then evaluated for use as a "fresh" or "prepared" specimen.
Cadaveric specimens for dissection are, in general, disposed of by cremation. The deceased may then be interred at a local cemetery. If the family wishes, the ashes of the deceased are then returned to the family. Many institutes have local policies to engage, support and celebrate the donors. This may include the setting up of local monuments at the cemetery.
Human cadavers are often used in medicine to teach anatomy or surgical instruction. Cadavers are selected according to their anatomy and availability. They may be used as part of dissection courses involving a "fresh" specimen so as to be as realistic as possible—for example, when training surgeons. Cadavers may also be pre-dissected by trained instructors. This form of dissection involves the preparation and preservation of specimens for a longer time period and is generally used for the teaching of anatomy.
Some alternatives to dissection may present educational advantages over the use of animal cadavers, while eliminating the problematic ethical issues. These alternatives include computer programs, lectures, three dimensional models, films, and other forms of technology. Concern for animal welfare is often at the root of objections to animal dissection. Studies show that some students reluctantly participate in animal dissection out of fear of real or perceived punishment or ostracism from their teachers and peers, and many do not speak up about their ethical objections.
One alternative to the use of cadavers is computer technology. At Stanford Medical School, software combines X-ray, ultrasound and MRI imaging for display on a screen as large as a body on a table. In a variant of this, a "virtual anatomy" approach being developed at New York University, students wear three dimensional glasses and can use a pointing device to "[swoop] through the virtual body, its sections as brightly colored as living tissue." This method is claimed to be "as dynamic as Imax [cinema]".
Proponents of animal-free teaching methodologies argue that alternatives to animal dissection can benefit educators by increasing teaching efficiency and lowering instruction costs while affording teachers an enhanced potential for the customization and repeat-ability of teaching exercises. Those in favor of dissection alternatives point to studies which have shown that computer-based teaching methods "saved academic and nonacademic staff time … were considered to be less expensive and an effective and enjoyable mode of student learning [and] … contributed to a significant reduction in animal use" because there is no set-up or clean-up time, no obligatory safety lessons, and no monitoring of misbehavior with animal cadavers, scissors, and scalpels.
With software and other non-animal methods, there is also no expensive disposal of equipment or hazardous material removal. Some programs also allow educators to customize lessons and include built-in test and quiz modules that can track student performance. Furthermore, animals (whether dead or alive) can be used only once, while non-animal resources can be used for many years—an added benefit that could result in significant cost savings for teachers, school districts, and state educational systems.
Several peer-reviewed comparative studies examining information retention and performance of students who dissected animals and those who used an alternative instruction method have concluded that the educational outcomes of students who are taught basic and advanced biomedical concepts and skills using non-animal methods are equivalent or superior to those of their peers who use animal-based laboratories such as animal dissection.
Elsewhere it has been reported that students’ confidence and satisfaction increased as did their preparedness for laboratories and their information-retrieval and communication abilities. Three separate studies at universities across the United States found that students who modeled body systems out of clay were significantly better at identifying the constituent parts of human anatomy than their classmates who performed animal dissection.
Another study found that students preferred using clay modeling over animal dissection and performed just as well as their cohorts who dissected animals.
In 2008, the National Association of Biology Teachers (NABT) affirmed its support for classroom animal dissection stating that they "Encourage the presence of live animals in the classroom with appropriate consideration to the age and maturity level of the students …NABT urges teachers to be aware that alternatives to dissection have their limitations. NABT supports the use of these materials as adjuncts to the educational process but not as exclusive replacements for the use of actual organisms."
The National Science Teachers Association (NSTA) "supports including live animals as part of instruction in the K-12 science classroom because observing and working with animals firsthand can spark students' interest in science as well as a general respect for life while reinforcing key concepts" of biological sciences. NSTA also supports offering dissection alternatives to students who object to the practice.
The NORINA database lists over 3,000 products which may be used as alternatives or supplements to animal use in education and training. These include alternatives to dissection in schools. InterNICHE has a similar database and a loans system.
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Anatomy (Greek anatomē, "dissection") is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science which 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 over immediate (embryology) and long (evolution) timescales. Anatomy and physiology, which study (respectively) the structure and function of organisms and their parts, make a natural pair of related disciplines, and they are often studied together. Human anatomy is one of the essential basic sciences that are applied in medicine.The discipline of anatomy is divided into macroscopic and microscopic anatomy. Macroscopic anatomy, or gross anatomy, is the examination of an animal's body parts using unaided eyesight. Gross anatomy also includes the branch of superficial anatomy. Microscopic anatomy involves the use of optical instruments in the study of the tissues of various structures, known as histology, and also in the study of cells.
The history of anatomy is characterized by a progressive understanding of the functions of the organs and structures of the human body. Methods have also improved dramatically, advancing from the examination of animals by dissection of carcasses and cadavers (corpses) to 20th century medical imaging techniques including X-ray, ultrasound, and magnetic resonance imaging.Aortic dissection
Aortic dissection (AD) occurs when an injury to the innermost layer of the aorta allows blood to flow between the layers of the aortic wall, forcing the layers apart. In most cases, this is associated with a sudden onset of severe chest or back pain, often described as "tearing" in character. Also, vomiting, sweating, and lightheadedness may occur. Other symptoms may result from decreased blood supply to other organs, such as stroke or mesenteric ischemia. Aortic dissection can quickly lead to death from not enough blood flow to the heart or complete rupture of the aorta.AD is more common in those with a history of high blood pressure, a number of connective tissue diseases that affect blood vessel wall strength including Marfan syndrome and Ehlers Danlos syndrome, a bicuspid aortic valve, and previous heart surgery. Major trauma, smoking, cocaine use, pregnancy, a thoracic aortic aneurysm, inflammation of arteries, and abnormal lipid levels are also associated with an increased risk. The diagnosis is suspected based on symptoms with medical imaging, such as computed tomography, magnetic resonance imaging, or ultrasound used to confirm and further evaluate the dissection. The two main types are Stanford type A, which involves the first part of the aorta, and type B, which does not.Prevention is by blood pressure control and not smoking. Management of AD depends on the part of the aorta involved. Dissections that involve the first part of the aorta usually require surgery. Surgery may be done either by an opening in the chest or from inside the blood vessel. Dissections that involve the second part of the aorta can typically be treated with medications that lower blood pressure and heart rate, unless there are complications.AD is relatively rare, occurring at an estimated rate of three per 100,000 people per year. It is more common in males than females. The typical age at diagnosis is 63, with about 10% of cases occurring before the age of 40. Without treatment, about half of people with Stanford type A dissections die within three days and about 10% of people with Stanford type B dissections die within one month. The first case of AD was described in the examination of King George II of Great Britain following his death in 1760. Surgery for AD was introduced in the 1950s by Michael E. DeBakey.Aortography
Aortography involves placement of a catheter in the aorta and injection of contrast material while taking X-rays of the aorta. The procedure is known as an aortogram. The diagnosis of aortic dissection can be made by visualization of the intimal flap and flow of contrast material in both the true lumen and the false lumen. The catheter has to be inserted through the right femoral artery, because in about two thirds of cases the aortic dissection spreads into the left common iliac artery.
The aortogram was previously considered the gold standard test for the diagnosis of aortic dissection, with a sensitivity of up to 80% and a specificity of about 94%. It is especially poor in the diagnosis of cases where the dissection is due to hemorrhage within the media without any initiating intimal tear.
The advantage of the aortogram in the diagnosis of aortic dissection is that it can delineate the extent of involvement of the aorta and branch vessels and can diagnose aortic insufficiency. The disadvantages of the aortogram are that it is an invasive procedure and it requires the use of iodinated contrast material.Aortography has largely been replaced by the diagnostic tools of MRI, CT, and transesophageal echocardiography (TEE) all of which have high sensitivities. TEE is favored in emergency situations, as it is relatively non-invasive and a rapid procedure (more so than MRI, which can takes hours).Autopsy
An autopsy (post-mortem examination, obduction, necropsy, or autopsia cadaverum) is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode and manner of death or to evaluate any disease or injury that may be present for research or educational purposes. (The term "necropsy" is generally reserved for non-human animals; see below). Autopsies are usually performed by a specialized medical doctor called a pathologist. In most cases, a medical examiner or coroner can determine cause of death and only a small portion of deaths require an autopsy.Cadaver
A cadaver is a dead human body that is used by medical students, physicians and other scientists to study anatomy, identify disease sites, determine causes of death, and provide tissue to repair a defect in a living human being. Students in medical school study and dissect cadavers as a part of their education. Others who study cadavers include archaeologists and artists.The term cadaver is used in courts of law to refer to a dead body, as well as by recovery teams searching for bodies in natural disasters. The word comes from the Latin word cadere ("to fall"). Related terms include cadaverous (resembling a cadaver) and cadaveric spasm (a muscle spasm causing a dead body to twitch or jerk). A cadaver graft (also called “postmortem graft”) is the grafting of tissue from a dead body onto a living human to repair a defect or disfigurement. Cadavers can be observed for their stages of decomposition, helping to determine how long a body has been dead.Cadavers have been used in art to depict the human body in paintings and drawings more accurately.Carotid artery dissection
Carotid artery dissection is a separation of the layers of the artery wall supplying oxygen-bearing blood to the head and brain and is the most common cause of stroke in young adults. (In vascular medicine, dissection is a blister-like de-lamination between the outer and inner walls of a blood vessel, generally originating with a partial leak in the inner lining.)Dissection may occur after physical trauma to the neck, such as a blunt injury (e.g. traffic collision), strangulation or chiropractic manipulation, but may also happen spontaneously.Dissection (band)
Dissection was a Swedish extreme metal band from Strömstad, formed in 1989 by guitarist, vocalist and main songwriter Jon Nödtveidt and bass guitarist Peter Palmdahl. Despite a number of lineup changes, Dissection released The Somberlain in 1993 and Storm of the Light's Bane in 1995, before splitting up in 1997 due to Nödtveidt's imprisonment for complicity in the murder of Josef Meddour.
After his release, Nödtveidt reformed the band in 2004 with new members whom he felt could "stand behind and live up to the demands of Dissection's Satanic concept." They released their third and final full-length album Reinkaos in April 2006, before disbanding that June. Nödtveidt said he had "reached the limitations of music as a tool for expressing what I want to express, for myself and the handful of others that I care about." Two months later, Nödtveidt committed suicide with a gun inside a circle of lit candles in his apartment in Hässelby.Dissection released a number of live albums and EPs before its final dissolution, and played a central role in the development of Sweden's black metal and death metal scenes, particularly through the influence of the first two albums; it has sometimes been described as part of the Gothenburg scene.Dissection (medical)
A dissection is a tear within the wall of a blood vessel, which allows blood to separate the wall layers. Usually, a dissection is an arterial wall dissection, but rarely it may be a vein wall dissection (VWD).By separating a portion of the wall of the artery (a layer of the tunica intima or tunica media), a dissection creates two lumens or passages within the vessel, the native or true lumen, and the "false lumen" created by the new space within the wall of the artery.Familial aortic dissection
Familial aortic dissection or FAD refers to the splitting of the wall of the aorta in either the arch, ascending or descending portions. FAD is thought to be passed down as an autosomal dominant disease and once inherited will result in dissection of the aorta, and dissecting aneurysm of the aorta, or rarely aortic or arterial dilation at a young age. Dissection refers to the actual tearing open of the aorta. However, the exact gene(s) involved has not yet been identified. It can occur in the absence of clinical features of Marfan syndrome and of systemic hypertension. Over time this weakness, along with systolic pressure, results in a tear in the aortic intima layer thus allowing blood to enter between the layers of tissue and cause further tearing. Eventually complete rupture of the aorta occurs and the pleural cavity fills with blood. Warning signs include chest pain, ischemia, and hemorrhaging in the chest cavity. This condition, unless found and treated early, usually results in death. Immediate surgery is the best treatment in most cases. FAD is not to be confused with PAU (penetrating atherosclerotic ulcers) and IMH (intramural hematoma), both of which present in ways similar to that of familial aortic dissection.Klein bottle
In topology, a branch of mathematics, the Klein bottle is an example of a non-orientable surface; it is a two-dimensional manifold against which a system for determining a normal vector cannot be consistently defined. Informally, it is a one-sided surface which, if traveled upon, could be followed back to the point of origin while flipping the traveler upside down. Other related non-orientable objects include the Möbius strip and the real projective plane. Whereas a Möbius strip is a surface with boundary, a Klein bottle has no boundary (for comparison, a sphere is an orientable surface with no boundary).
The Klein bottle was first described in 1882 by the German mathematician Felix Klein. It may have been originally named the Kleinsche Fläche ("Klein surface") and then misinterpreted as Kleinsche Flasche ("Klein bottle"), which ultimately may have led to the adoption of this term in the German language as well.Madhusudan Gupta
Pandit Madhusudan Gupta (Bengali: মধুসূদন গুপ্ত) (1800 – 15 November 1856) was a Bengali Brahmin translator and Ayurvedic practitioner who was also trained in Western medicine and is credited with having performed India's first human dissection at Calcutta Medical College (CMC) in 1836, almost 3,000 years after Susruta. A subject of debate, the precise date and authenticity has been a topic of discussion.
Born into a Vaidya family, he studied Ayurvedic medicine at the Sanskrit College and progressed to teacher. Here, he began translations of a number of English texts into Sanskrit, including Hooper's Anatomists’ Ved-mecum. In addition, he attended anatomy and medicine lectures, becoming familiar with the developing clinical-anatomical medicine of Europe.
In 1835, he was transferred to the new CMC, where he was fundamental in gathering Indian support for practical anatomy and in breaking down Hindu taboos on touching the dead, consequently taking sole responsibility for the first human dissection, performed under the guidance of Professor Henry Goodeve and assisted by four other Hindu students. Controversies regarding the exact date of the first procedure, whether other students had performed it before and whether a military salute was given, remain. Despite any discrepancies, this singular act of dissection has become symbolic of the move of western medicine into India.
As a practitioner, he was successful and well regarded amongst his Indian contemporaries as well as by his European colleagues. In 1837, his involvement with the General Committee of the Fever Hospital and Municipal Improvements included recommendations for Kolkata's sanitation, a plead for better maternal care and a commendation to the smallpox vaccinators of Kolkata. His contributions to the research on puberty helped dismiss myths about the discrepancy of menarche between Indian and British women.
Gupta died from diabetic septicaemia in 1856, at the age of 56.Prosection
A prosection is the dissection of a cadaver (human or animal) or part of a cadaver by an experienced anatomist in order to demonstrate for students anatomic structure. In a dissection, students learn by doing; in a prosection, students learn by either observing a dissection being performed by an experienced anatomist or examining a specimen that has already been dissected by an experienced anatomist (etymology: Latin pro- "before" + sectio "a cutting")A prosection may also refer to the dissected cadaver or cadaver part which is then reassembled and provided to students for review.Prosector
A prosector is a person with the special task of preparing a dissection for demonstration, usually in medical schools or hospitals. Many important anatomists began their careers as prosectors working for lecturers and demonstrators in anatomy and pathology.
The act of prosecting differs from that of dissecting. A prosection is a professionally prepared dissection prepared by a prosector – a person who is well versed in anatomy and who therefore prepares a specimen so that others may study and learn anatomy from it. A dissection is prepared by a student who is dissecting the specimen for the purpose of learning more about the anatomical structures pertaining to that specimen. The term dissection may also be used to describe the act of cutting. Therefore, a prosector dissects to prepare a prosection.
Prosecting is intricate work where numerous tools are used to produce a desired specimen. Scalpels and scissors allow for sharp dissection where tissue is cut, e.g. the biceps brachii muscle can be removed from the specimen by cutting the origin and insertion with a scalpel. Probes and the prosector's own fingers are examples of tools used for blunt dissection where tissue may be separated from surrounding structures without cutting, i.e. the bellies of biceps brachii and coracobrachialis muscle were made clearer by loosening the fascia between the two muscles with a blunt probe.Retroperitoneal lymph node dissection
Retroperitoneal lymph node dissection (RPLND) is a surgical procedure to remove abdominal lymph nodes. It is used to treat testicular cancer, as well as to help establish the exact stage and type of the cancer.Spontaneous coronary artery dissection
A spontaneous coronary artery dissection (SCAD) is a rare, sometimes fatal traumatic condition, with eighty percent of cases affecting women. One of the coronary arteries develops a tear, causing blood to flow between the layers which forces them apart. Studies of the disease place the mortality rate at around 70%.SCAD is a primary cause of myocardial infarction (MI) in young, fit, healthy women (and some men) with no obvious risk factors. These can often occur during late pregnancy, postpartum and peri-menopausal periods.Squaring the square
Squaring the square is the problem of tiling an integral square using only other integral squares. (An integral square is a square whose sides have integer length.) The name was coined in a humorous analogy with squaring the circle. Squaring the square is an easy task unless additional conditions are set. The most studied restriction is that the squaring be perfect, meaning the sizes of the smaller squares are all different. A related problem is squaring the plane, which can be done even with the restriction that each natural number occurs exactly once as a size of a square in the tiling. The order of a squared square is its number of constituent squares.Superior rectus muscle
The superior rectus muscle is a muscle in the orbit. It is one of the extraocular muscles. It is innervated by the superior division of the oculomotor nerve (Cranial Nerve III). In the primary position (looking straight ahead), the superior rectus muscle's primary function is elevation, although it also contributes to intorsion and adduction.Turner syndrome
Turner syndrome (TS), also known as 45,X or 45,X0, is a condition in which a female is partly or completely missing an X chromosome. Signs and symptoms vary among those affected. Often, a short and webbed neck, low-set ears, low hairline at the back of the neck, short stature, and swollen hands and feet are seen at birth. Typically, they develop menstrual periods and breasts only with hormone treatment, and are unable to have children without reproductive technology. Heart defects, diabetes, and low thyroid hormone occur more frequently. Most people with TS have normal intelligence. Many have troubles with spatial visualization that may be needed for mathematics. Vision and hearing problems occur more often.Turner syndrome is not usually inherited from a person's parents. No environmental risks are known, and the mother's age does not play a role. Turner syndrome is due to a chromosomal abnormality in which all or part of one of the X chromosomes is missing or altered. While most people have 46 chromosomes, people with TS usually have 45. The chromosomal abnormality may be present in just some cells in which case it is known as TS with mosaicism. In these cases, the symptoms are usually fewer and possibly none occur at all. Diagnosis is based on physical signs and genetic testing.No cure for Turner syndrome is known. Treatment may help with symptoms. Human growth hormone injections during childhood may increase adult height. Estrogen replacement therapy can promote development of the breasts and hips. Medical care is often required to manage other health problems with which TS is associated.Turner syndrome occurs in between one in 2,000 and one in 5,000 females at birth. All regions of the world and cultures are affected about equally. Generally people with TS have a shorter life expectancy, mostly due to heart problems and diabetes. Henry Turner first described the condition in 1938. In 1964, it was determined to be due to a chromosomal abnormality.Vertebral artery dissection
Vertebral artery dissection (VAD) is a flap-like tear of the inner lining of the vertebral artery, which is located in the neck and supplies blood to the brain. After the tear, blood enters the arterial wall and forms a blood clot, thickening the artery wall and often impeding blood flow. The symptoms of vertebral artery dissection include head and neck pain and intermittent or permanent stroke symptoms such as difficulty speaking, impaired coordination and visual loss. It is usually diagnosed with a contrast-enhanced CT or MRI scan.Vertebral dissection may occur after physical trauma to the neck, such as a blunt injury (e.g. traffic collision), strangulation or chiropractic manipulation, but may also happen spontaneously. 1–4% of spontaneous cases have a clear underlying connective tissue disorder affecting the blood vessels. Treatment is usually with either antiplatelet drugs such as aspirin or with anticoagulants such as heparin or warfarin.Vertebral artery dissection is less common than carotid artery dissection (dissection of the large arteries in the front of the neck). The two conditions together account for 10–25% of non-hemorrhagic strokes in young and middle-aged people. Over 75% recover completely or with minimal impact on functioning, with the remainder having more severe disability and a very small proportion (about 2%) dying from complications. It was first described in the 1970s by the Canadian neurologist C. Miller Fisher.