It has been used for over 2,400 years as a part of traditional Chinese medicine. In the western world, arsenic compounds, such as salvarsan, were used extensively to treat syphilis before penicillin was introduced. It was eventually replaced as a therapeutic agent by sulfa drugs and then by other antibiotics. Arsenic was also an ingredient in many tonics (or "patent medicines"). In addition, during the Elizabethan era, some women used a mixture of vinegar, chalk, and arsenic applied topically to whiten their skin. This use of arsenic was intended to prevent aging and creasing of the skin, but some arsenic was inevitably absorbed into the blood stream.During the Victorian era (late 19th century) in the United States, U.S. newspapers advertised "arsenic complexion wafers" that promised to remove facial blemishes such as moles and pimples.Some pigments, most notably the popular Emerald Green (known also under several other names), were based on arsenic compounds. Overexposure to these pigments was a frequent cause of accidental poisoning of artists and craftsmen. Arsenic became a favored method for murder of the Middle Ages and Renaissance, particularly among ruling classes in Italy allegedly. Because the symptoms are similar to those of cholera, which was common at the time, arsenic poisoning often went undetected. : 63   By the 19th century, it had acquired the nickname "inheritance powder," perhaps because impatient heirs were known or suspected to use it to ensure or accelerate their inheritances.
A bifid rib is a congenital abnormality of the rib cage and associated muscles and nerves which occurs in about 1.2% of humans. Bifid ribs occur in up to 8.4% of Samoans. The sternal end of the rib is cleaved into two. It is usually unilateral. Bifid ribs are usually asymptomatic, and are often discovered incidentally by chest X-ray. Effects of this neuroskeletal anomaly can include respiratory difficulties, neurological difficulties, limitations, and limited energy from the stress of needing to compensate for the neurophysiological difficulties. An unstable bifid rib may lead to slipping rib syndrome.Another association is with odontogenic keratocysts of the jaw, which may behave aggressively and have a high propensity to recur when treated with simple enucleation and curettage. When seen together, the patient is likely to have nevoid basal-cell carcinoma syndrome (Gorlin-Goltz syndrome). See also
List of radiographic findings associated with cutaneous conditions


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