Managed care and the infectious diseases specialist.

There is growing demand to contain health care costs and to reassess the value of medical services. The traditional hospital, academic, and research roles of the infectious disease (ID) specialist are threatened, yet there is an increasing need for expertise because of growing antimicrobial resistance and emerging pathogens. Opportunities exist to develop and expand services for the care of patients infected with human immunodeficiency virus and in infection control, epidemiology, outcomes research, outpatient intravenous therapy, and resource management. It is important for ID physicians to appreciate the principles involved in managed care and the areas in which ID services can be valuable. To be effective, physicians need to know about tools such as practice guidelines, physician profiling, outcomes monitoring, computerized information management, risk sharing, networking, and marketing, as well as related legal issues. With a positive attitude toward learning, application, and leadership, ID physicians can redefine their role and expand their services through managed care.

Biochemical and cytological heterogeneity of the differentiating cells of the cellular slime mould Dictyostelium discoideum.

1. The slug stage of the cellular slime mould Dictyostelium discoideum has been shown to contain two types of cell, which differ in buoyant density. 2. These two cell types also differ in cytological appearance and histochemical behaviour and have very different enzymic activities. 3. Evidence is presented suggesting that the lighter of these two cell types corresponds to cells from the posterior region of the slug (pre-spore cells) and the heavier of the two to cells from the anterior region of the slug (pre-stalk cells).