出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/04/13 23:25:13」(JST)
Catgut is a type of cord[1] that is prepared from the natural fibre found in the walls of animal intestines.[2] Usually sheep or goat intestines are used, but it is occasionally made from the intestines of cattle,[3] hogs, horses, mules, or donkeys.[citation needed] Despite its name, no cat intestines are used in catgut.
The word catgut may have been an abbreviation of the word "cattlegut". Alternatively, it may have derived by folk etymology from kitgut or kitstring—the word kit, meaning fiddle, having at some point been confused with the word kit for a young cat.[4]
In order to prepare catgut, the intestines are cleaned, freed from fat, and steeped in water. After that, the external membrane is scraped off with a blunt knife. The intestines are then once again steeped for some time in lye (a caustic alkali, usually potassium hydroxide or sodium hydroxide), and then smoothed and equalized by drawing out. It is found that lean animals yield the toughest gut.[5] Next the prepared gut strands are twisted together to make the string. The diameter of the string is determined by the thickness of the individual guts and by the number that are used. For example, a very thin string such as a violin E will use only three or four guts, whereas a very heavy string, such as a double bass string, may use twenty or more. After twisting and drying, the strings are polished to the requisite diameter. Before the twentieth century the strings were simply rubbed with an abrasive to smooth them, while today they are generally ground down to the desired diameter using a centerless grinder. After drying and polishing the strings are bleached using the antiseptic action of the fumes of burning sulfur (i.e. sulfur dioxide), dyed if necessary, and sorted into sizes. Catgut sutures are normally treated with chromium salt solution to resist body enzymes, to slow the absorption process, and are called catgut chromic sutures whereas untreated catgut sutures are called catgut plain sutures.[6] Before 1900 the best strings for musical instruments were reputedly from Italy. The best were considered to be from Naples, though excellent strings were also produced in Rome and other Italian cities. Today high quality gut strings are produced mostly in Italy, Germany, and the United States, though they are also made elsewhere, for example in India and Morocco, for local use.
For a long period, catgut was the most common material for the strings of harps, lutes, violins, violas and cellos, acoustic guitars and other stringed musical instruments, as well as older marching snare drums. Most musical instruments produced today use strings with cores made of other materials, generally steel or synthetic polymer. Gut strings are the natural choice for many classical and baroque string players,[citation needed] and gut strings are still most commonly preferred in concert-tension pedal/grand and some lever harps because they give a richer, darker sound as well as withstanding high tension within low alto, tenor, and high-bass ranges.[citation needed] Acoustic guitars moved away from gut strings in the early 1900s when the C. F. Martin & Company introduced steel strings. These gave greater volume to the guitar. "The demand for steel came from ensemble players, who couldn't make themselves heard clearly without it."[7] Within a few years the majority of Martin guitars were made with steel strings to accommodate the demand.
Catgut suture was once a widely used material in surgical settings. There is debate about whether to continue using catgut in a medical setting, since cotton is usually cheaper and wounds closed with either cotton or synthetic threads are less prone to infection.[8] Catgut sutures continue to be used in developing countries where they are locally less expensive and easier to obtain.[citation needed] Natural gut is still used as a high-performance string in tennis racquets, although it had more popularity in the past and is being displaced by synthetic strings.
[T]here is no such thing as crude catgut or catgut unmanufactured. Catgut is a manufactured article and a finished product; the crude form are the intestines or guts of sheep or other animals.
Catgut sutures are derived from the submucosal layer of the small intestine of sheep and the serosal layer of the small intestine of cattle.
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リンク元 | 「腸線」「カットグット」 |
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