Soft contact lenses
Article Abstract:
The advantages and disadvantages of soft contact lenses are reviewed in this article, which also describes the newest types of soft lenses. In general, soft lenses are considered more comfortable than hard lenses, which allows patients to wear them for longer periods of time. Soft lenses are also less likely to pop out of the eye than hard lenses, so they are preferable for wear during physical activity. The downside of soft lenses are that they often do not provide as sharp an image as hard lenses, and they also may need to be replaced as often as every six months, while hard lenses can last for years. Soft lenses must be cleaned and disinfected according to careful procedures to prevent the build-up of protein deposits. These deposits can cause chronic irritation of the conjunctiva (conjunctivitis), which may necessitate reducing the time they are worn or even giving up the lenses altogether. A more serious complication of using soft lenses is ulcerative keratitis, the formation of infected ulcers on the cornea due to bacteria which adhere to the protein deposits. This condition is sometimes difficult to treat and can lead to permanent loss of vision; this is much more common among users of extended-wear lenses, which can be left in the eye for as long as one month. The United States Food and Drug Administration has recommended that extended-wear lenses be worn for only one to seven days before they are cleaned or discarded. A new type of soft lens is the disposable extended-wear lens, which is worn for one week and thrown away; unfortunately there have already been cases of ulcerative keratitis with these lenses, which cost about $30 per month. Other new products include bifocal contact lenses, soft lenses that correct astigmatism, and lenses that change the eye color; these products are evaluated. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Medical Letter on Drugs and Therapeutics
Subject: Health
ISSN: 0025-732X
Year: 1990
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Better cooking through chemistry: that's the wisdom of Harold McGee, master of the Bunsen burner
Article Abstract:
McGee is hard at work revising his biochemistry text 'On Food and Cooking.' He is an ardent experimental chef, often cooking dinners for his Palo Alto, CA, family. His unique formulae for black beans, pine-cure salmon, avocado-lime mash, fresh cheese, and other concoctions are provided.
Publication Name: The New York Times Magazine
Subject:
ISSN: 0028-7822
Year: 1997
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Pep rally and pom-poms
Article Abstract:
Five appetizer recipes for class reunion cocktail parties are presented. The recipes are Marinated Shrimp and Artichokes, Hot Crab Dip, Zippy Cheese Crostini, Bill D's Black-Eyed Pea Dip and Herb-Pepper Cheese.
Publication Name: Southern Living
Subject: Home and garden
ISSN: 0038-4305
Year: 1997
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