disease usually excluded by body defences.

An organism capable of causing disease only in a host whose resistance is lowered--usually by other diseases or by drugs

describes a microorganism that usually does not infect a host but under certain circumstances infects and causes disease.

infection Infection by organisms that would be harmless to a healthy person, but cause infection in those with a weakened immune system (for example, persons with AIDS or chemotherapy patients).

A disease caused by a microorganism that does not ordinarily cause disease but becomes pathogenic under certain circumstances.

Disease usually excluded by body defenses

adapting one's actions to the immediate circumstances, as in taking advantage of whatever food is available. References Clark, Tim W. and Mark Stromberg. 1987. Mammals in Wyoming. Lawrence: University of Kansas, Museum of Natural History. Jones, Jr., J. Knox, and others, 1983. Mammals of the Northern Great Plains. Lincoln, University of Nebraska Press. Whitaker, Jr., John O., 1980. The Audubon Society Field Guide to North American Mammals. New York: Alfred A. Knopf. Selected Resources for Teachers There are surprisingly few children's books about fox squirrels. Bare, Colleen Stanley. Tree Squirrels. New York: Dodd, Mead & Company. 1983. Laycock, George. Squirrels. New York: Four Winds Press. 1975.

A phrase generally used by advisers and managers to describe investments in underperforming and/or undermanaged assets that hold the expectation of near-term increases in cash flow and value. Total return objectives for opportunistic strategies tend to be 20 percent or higher. Opportunistic investments typically involve a high degree of leverage - typically 60 percent to 100 percent on an asset basis and 60 percent to 80 percent on a portfolio basis. [Go to source