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A simple and rapid method is described for processing organ and water samples for the identification of diatoms so that they can be studied and recorded for taxonomic and diagnostic purposes. Samples are treated with concentrated nitric acid; the fluid obtained is centrifuged, and its sediment is dried, coated, and examined under the scanning electron microscope. The method does not alter the morphology of diatoms and allows the study of freshwater and seawater species present in the organs of bodies found in the water, making possible the diagnosis of drowning under specific conditions.  相似文献   
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Book Reviews in This Article:
Getting Rid of Patients: Contradictions in the Socialization of Physicians . By Terry Mizrahi
Physicians and Social Change . By John Colombotos and Corinne Kirchner
Changing Values in Medicine . Edited by Eric J. Cassell and Mark Siegler
Professional Ethics and Primary Care Medicine: Beyond Dilemmas and Decorum . By Harmon L. Smith and Larry R. Churchill
Physician—Patient Decision-Making: A Study in Medical Ethics . By Douglas N. Walton
With Dignity: The Search for Medicare and Medicaid . By Sheri I. David
The Dismissal of Students with Mental Disorders. Legal Issues, Policy Considerations, and Alternative Responses .
Courtroom Toxicology . By Marshall Houts, Randall C. Baselt, and Robert H. Cravey  相似文献   
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In order to cooperate with voluntary screening programs aimed at the surveillance of the HIV epidemic in Finland, we have studied medicolegal autopsies for HIV antibodies since 1986 using an enzyme immunoassay on postmortem sera. The investigation covered 47.4% and 39.2%, respectively, of all deaths under the age of 65 years in the metropolitan areas of Helsinki and Turku--two cities on the densely populated southern coast of Finland from which most HIV infections have thus far been detected. Nine HIV-positive cases (0.12%) were detected among the 7305 medicolegal autopsies tested in 1986 to 1990. This figure is higher than the prevalence of 0.01 to 0.03% in voluntary screening programs for the general population would suggest. Seven of our cases had previously tested positive, and two were previously unknown cases, indicating that people at high risk are clustered in the medicolegal autopsy series. Of the six cases in an early stage of infection, three committed suicide suggesting the importance of HIV-screening in suicide cases in tracing symptomless HIV carriers. Five of the cases were detected in 1990, a year when the number of new HIV infections had more than doubled compared to the previous two years. This suggests that testing of medicolegal autopsies as surrogate tests for the population gives useful information even in low-prevalence areas like Finland. Such testing has none of the ethical problems of many other back-up surveys, and may be particularly sensitive to early changes in epidemiology.  相似文献   
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