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HIV infection is now perceived as the end stage of a chronic disease that is spreading most rapidly among blacks and Hispanics. The politics of the HIV epidemic in the 1980s were dominated by four interacting factors: fear and fascination; who had the disease and to whom it seemed to be spreading; the endemic problems of United States social policy; and the impact on policy of advances in scientific knowledge. This paper analyzes the political history of each of these factors and describes the dominant policies of the federal government and the states regarding HIV in the areas of surveillance, prevention, research, and financing. Four uncertainties will have a profound influence on the future politics of the HIV epidemic: how the states and the federal government will address the general problems of paying for the care of people with chronic diseases and providing access to care for the uninsured and the underinsured; the number and distribution of the sexual behaviors that transmit infection with HIV and the effectiveness of policies to persuade people to modify these behaviors; precisely who uses addictive drugs and the effectiveness of measures to change their behavior; and the natural history of the virus.  相似文献   
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Postmortem changes in sulfide concentrations in body tissues were examined in autopsied rats exposed to hydrogen sulfide concentrations of 550 to 650 ppm, and in nonexposed rats and humans. Analyses were made by gas chromatography, following an extractive alkylation. Sulfide concentrations in the blood, liver, and kidneys of rats increased in both the exposed and nonexposed groups, depending on the lapse of time after death. On the other hand, the lung, brain, and muscle showed little or no change in sulfide concentration with elapse of time after death. The data obtained from human tissues were almost the same as those for rats, except data for blood, in which no or little increase of sulfide was observed.  相似文献   
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De Vault  James M. 《Public Choice》2002,110(1-2):1-22
This study examines the unfair trade decisions of the InternationalTrade Commission (ITC) and how they have been affected by Congress.It begins by identifying the means Congress can use to influenceITC decisions and then estimates both the extent to which thesemeans have been used and the extent to which they have shaped theITC's behavior. The study reaches two conclusions. First, Congresshas tried to shape the ITC's behavior, but it has not tried tomicromanage this behavior. Second, while the ITC's behavior hasbeen influenced by Congress, congressional influence is not asimportant as other factors, such as statutory criteria.  相似文献   
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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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