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Contact Dermatitis
Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to chemical or physical agents. Symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, or swelling. These rashes are not contagious or life-threatening, but can be very uncomfortable. Contact dermatitis results from either exposure to allergens ( allergic contact dermatitis), or irritants ( irritant contact dermatitis). Allergic contact dermatitis involves a delayed type of hypersensitivity and previous exposure to an allergen to produce a reaction. Irritant contact dermatitis is the most common type and represents 80% of all cases. It is caused by prolonged exposure to irritants, leading to direct injury of the epidermal cells of the skin, which activates an immune response, resulting in an inflammatory cutaneous reaction. Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight. Diagnosis of allergic contact dermati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allergic Contact Dermatitis
Allergic contact dermatitis (ACD) is a form of contact dermatitis that is the manifestation of an allergic response caused by contact with a substance; the other type being irritant contact dermatitis (ICD). Although less common than ICD, ACD is accepted to be the most prevalent form of immunotoxicity found in humans. By its allergic nature, this form of contact dermatitis is a hypersensitive reaction that is atypical within the population. The mechanisms by which these reactions occur are complex, with many levels of fine control. Their immunology centres on the interaction of immunoregulatory cytokines and discrete subpopulations of T lymphocytes. Signs and symptoms The symptoms of allergic contact dermatitis are very similar to the ones caused by irritant contact dermatitis, which makes the first even harder to diagnose. The first sign of allergic contact dermatitis is the presence of the rash or skin lesion at the site of exposure. Depending on the type of allergen causi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Allergy
Nickel allergy is any of several allergy, allergic conditions provoked by exposure to the chemical element nickel. Nickel allergy often takes the form of nickel allergic contact dermatitis (Ni-ACD), a form of allergic contact dermatitis (ACD). Ni-ACD typically causes a rash that is red and itchy and that may be bumpy or scaly. The main treatment for it is avoiding contact with nickel-releasing metals, such as inexpensive jewelry. Another form of nickel allergy is a systemic disease, systemic form: systemic nickel allergy syndrome (SNAS) can mimic some of the symptoms of irritable bowel syndrome (IBS) and also has a dermatologic component. Signs and symptoms The most common sign of nickel allergy is inflammation of the skin at an area that comes into regular contact with nickel. This often takes the form of a Erythema, reddened patch of skin with raised bumps (papules) or small blisters (Vesicle (dermatology), vesicles), and edema. People with chronic dermatitis tend to have dry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatology
Dermatology is the branch of medicine dealing with the Human skin, skin.''Random House Webster's Unabridged Dictionary.'' Random House, Inc. 2001. Page 537. . It is a speciality with both medical and surgical aspects. A List of dermatologists, dermatologist is a specialist medical doctor who manages diseases related to skin. Etymology Attested in English in 1819, the word "dermatology" derives from the Ancient Greek, Greek δέρματος (''dermatos''), genitive of δέρμα (''derma''), "skin" (itself from δέρω ''dero'', "to flay") and -λογία ''wikt:-logia, -logia''. Neo-Latin ''dermatologia'' was coined in 1630, an anatomical term with various French and German uses attested from the 1730s. History In 1708, the first great school of dermatology became a reality at the famous Hôpital Saint-Louis in Paris, and the first textbooks (Willan's, 1798–1808) and atlases (Jean-Louis-Marc Alibert, Alibert's, 1806–1816) appeared in print around the same time.Freedber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blisters
A blister is a small pocket of body fluid (lymph, Serum (blood), serum, Plasma (blood), plasma, blood, or pus) within the Epidermis, upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are filled with a clear fluid, either Serum (blood), serum or Blood plasma, plasma. However, blisters can be filled with blood (known as "blood blisters") or with pus (for instance, if they become infected). Smaller blisters are called Bleb (medicine), ''blebs''. The word "blister" entered English in the 14th century. It came from the Middle Dutch and was a modification of the Old French , which meant a leprous nodule—a rise in the skin due to leprosy. In dermatology, the words cutaneous condition#Vesicle, ''vesicle'' and ''bulla'' refer to blisters of smaller or greater size, respectively. Some sources recommend not to pop a blister. If popped, bacteria can enter. Excess skin should not necessarily be remo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkyl Resorcinol
Alkylresorcinols (ARs), also known as resorcinolic lipids, are amphiphilic phenolic lipids characterised by a non-polar odd-numbered alkyl side chain with up to 27 carbon atoms attached to a polar resorcinol (1,3-dihydroxybenzene) ring. Natural sources of alkylresorcinols Alkylresorcinols are relatively rare in nature and are reported to be found in fungi, bacteria, and some lower and higher plants. DB-2073 is an antibiotic isolated from the broth culture of ''Pseudomonas'' sp. They are also the main constituents of the outer shell of the cyst of ''Azotobacter''. Among the plant sources, the shell oil of cashew nut ( ''Anacardium occidentale'' L.) has the highest amount of ARs, which consists of 20% phenolic lipids. Moreover, ARs were found in the peels and pulp of peas ( ''Pisum sativum'' L.), pulp and leaves of ginkgo ( ''Ginkgo biloba'' L.), pulp and peels of mango ( ''Mangifera indica'' L.), and in some cereals. In the case of cereals, the hyaline layer, inner pericarp, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poison Sumac
''Toxicodendron vernix'', commonly known as poison sumac, or swamp-sumach, is a woody shrub or small tree growing to tall. It was previously known as ''Rhus vernix''. This plant is also known as thunderwood, particularly where it occurs in the southern United States. Like its toxic relatives poison ivy and poison oak, all parts of the plant contain a resin called urushiol, which causes skin and mucous membrane irritation to humans. When the plant is burned, inhalation of the smoke may cause the rash to appear on the lining of the lungs, causing extreme pain and possibly fatal respiratory difficulty. Description Poison sumac is a shrub or small tree, growing up to nearly in height. Each pinnate leaf has 7–13 leaflets, each of which is long. These are oval-to-oblong; acuminate (tapering to a sharp point); cuneate (wedge-shaped) at the base; undulate (wavy-edged); with an underside that is glabrous (hairless) or slightly pubescent (down-like hair) beneath. The stems along ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Poison-oak
''Toxicodendron diversilobum'' (syn. ''Rhus diversiloba''), commonly named Pacific poison oak or western poison oak, is a woody vine or shrub in the sumac family, Anacardiaceae. It is widely distributed in western North America, inhabiting conifer and mixed broadleaf forests, woodlands, grasslands, and chaparral biomes.C. Michael Hogan (2008)"Western poison-oak: ''Toxicodendron diversilobum''", GlobalTwitcher, ed. Nicklas Strömberg Peak flowering occurs in May. Like other members of the genus '' Toxicodendron'', ''T. diversilobum'' causes itching and allergic rashes in most people after contact by touch or smoke inhalation. Despite its name, it is not closely related to oaks, nor is it a true tree. Description ''Toxicodendron diversilobum'' is extremely variable in growth habit and leaf appearance. It grows as a dense tall shrub in open sunlight, a treelike vine and may be more than long with an trunk, as dense thickets in shaded areas, or any form in between. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poison Ivy
Poison ivy is a type of allergenic plant in the genus '' Toxicodendron'' native to Asia and North America. Formerly considered a single species, '' Toxicodendron radicans'', poison ivies are now generally treated as a complex of three separate species: ''T. radicans'', '' T. rydbergii'', and '' T. orientale''. They are well known for causing urushiol-induced contact dermatitis, an itchy, irritating, and sometimes painful rash, in most people who touch them. The rash is caused by urushiol, a clear liquid compound in the plant's sap. They are variable in appearance and habit, and despite its common name, it is not a "true" ivy ('' Hedera''), but rather a member of the cashew and pistachio family ( Anacardiaceae). ''T. radicans'' is commonly eaten by many animals, and the seeds are consumed by birds, but poison ivy is most often thought of as an unwelcome weed. Species Three species of poison ivy are generally recognised; they are sometimes considered subspec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxicodendron
''Toxicodendron'' is a genus of flowering plants in the sumac family, Anacardiaceae. It contains trees, shrubs and woody vines, including poison ivy, poison oak, and the lacquer tree. All members of the genus produce the skin-irritating oil urushiol, which can cause a severe allergic reaction. The generic name is derived from the Greek words τοξικόν (''toxikón''), meaning "poison," and δένδρον (''déndron''), meaning "tree". The best-known members of the genus in North America are eastern poison ivy ''( T. radicans)'' and western poison oak ('' T. diversilobum''), both ubiquitous throughout much of their respective region. The resins of certain species native to Japan, China and other Asian countries, such as lacquer tree ('' T. vernicifluum'') and wax tree ('' T. succedaneum''), are used to make lacquer, and, as a byproduct of lacquer manufacture, their berries are used to make japan wax. Description Plants in the genus have pinn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urushiol
Urushiol is an oily mixture of organic compounds with Allergic contact dermatitis, allergenic properties found in plants of the Family (biology), family Anacardiaceae, especially ''Toxicodendron'' ''spp.'' (e.g., poison oak, Toxicodendron vernicifluum, Chinese lacquer tree, Toxicodendron radicans, poison ivy, Toxicodendron vernix, poison sumac), Comocladia, ''Comocladia spp.'' (maidenplums), Metopium, ''Metopium spp''. (poisonwood), and also in parts of the Mangifera indica, mango tree and the fruit of the cashew tree. In most individuals, urushiol causes an allergic skin rash on contact, known as urushiol-induced contact dermatitis. The name urushiol is derived from the Japanese language, Japanese word for the lacquer tree, . The oxidation and polymerization of urushiol in the tree's sap in the presence of moisture allows it to form a hard lacquer, which is used to produce traditional Chinese, Korean, and Japanese lacquerware. History Although urushiol-containing lacquers a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Americas
The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a single continent, the Americas or America is the 2nd largest continent by area after Asia, and is the 3rd largest continent by population. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with their Lists of islands of the Americas, associated islands, the Americas cover 8% of Earth's total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by large river basins, such as the Amazon basin, Amazon, St. Lawrence River–Great Lakes, Mississippi River System, Mississippi, and Río de la Plata Basin, La Plata basins. Since the Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromium
Chromium is a chemical element; it has Symbol (chemistry), symbol Cr and atomic number 24. It is the first element in Group 6 element, group 6. It is a steely-grey, Luster (mineralogy), lustrous, hard, and brittle transition metal. Chromium 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 polishing, polished while resisting tarnishing. Polished chromium reflects almost 70% of the visible spectrum, and almost 90% of infrared, infrared light. The name of the element is derived from the Ancient Greek, Greek word χρῶμα, ''chrōma'', meaning color, because many chromium compounds are intensely colored. Indust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
