Prodrugs: advantage or disadvantage?
Article Abstract:
Prodrugs are drugs which have a biological effect only after partial metabolism by tissues. Some prodrugs have a limited amount of activity themselves, while most are dependent on complete transformation to metabolites before effects on tissues are obtained. Oral contraceptives, which contain derivatives of estrogen and of progesterone, have made use of prodrugs with each type of activity. Studies comparing the tissue handling and effectiveness of prodrugs and their corresponding active metabolites have been infrequent. The information gained from such studies is reviewed in this article. Pairs of these compounds, including lynesterenol and norethisterone, and mestranol and ethinyl estradiol, are discussed. Differences in time lapses until peak blood levels are reached are not apparently important in the biological effects. Differences in the time for elimination of drug from circulation may lead to differences in bioequivalence among drug pairs. If endocrine activities differ between prodrug and metabolite, as do those of norgestimate and norethisterone acetate, then additional metabolic pathways may be available for transformation of the compound which has additional endocrine effects. Much work is needed with prodrug compounds to better understand the benefits associated with prodrugs and their metabolites. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: American Journal of Obstetrics and Gynecology
Subject: Health
ISSN: 0002-9378
Year: 1990
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Survival A La Carte
Article Abstract:
Survival depends on several factors such as fire for warmth and rescue as well as for potable water and cooking, shelter from the elements, water and food, although one can live without it for a couple weeks and some means of rescue. Some of the critical elements of survival are discussed such as positive attitude, a strong will and communicating to someone about going and how long one is expected to be there and how to contact if one does not report back.
Publication Name: American Rifleman
Subject: Travel, recreation and leisure
ISSN: 0003-083X
Year: 2005
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IKEA culture
Article Abstract:
Innovative marketing, inexpensive servicing, appealing design, and a highly efficient functional system makes IKEA a household name in the business of home furnishings. The Sweden-based retailer has over 180 million clients across 67 countries. IKEA designs innovative furniture that is inexpensive and must be assembled. Young adults are the primary market. The company's marketing strategies are unparalleled despite its low key public image.
Publication Name: I.D.
Subject: Business
ISSN: 0894-5373
Year: 1996
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