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Lyophilized Sigma Type III trypsin has been applied to latent prints two weeks to two months old. This trypsin preparation eliminates the background problems that had been encountered with old prints in a previous study. Zinc chloride treatment of latent prints previously exposed to ninhydrin enhances their detectability upon laser examination. However, it has been reported that the zinc chloride reaction occasionally fails to occur. Accordingly, we have investigated the optimization of this reaction. We find that high humidity and elevated temperature, particularly the former, are needed. Cadmium nitrate, although it produces weaker fluorescence than zinc chloride, may at times be useful. Reaction conditions are much the same as those for zinc chloride.  相似文献   
947.
When infants die suddenly of acute dehydration, clinical signs and autopsy findings may be equivocal or absent, and microbiologic cultures often are not helpful. Vitreous humor electrolyte and urea nitrogen concentrations were measured in 53 infants dying of gastrointestinal infections, sudden infant death syndrome (SIDS), other infectious diseases, and miscellaneous causes to determine whether these parameters would assist in the recognition and confirmation of deaths resulting from dehydration. Significant differences were found when comparing the mean sodium and urea nitrogen levels of infants dying of gastrointestinal infections with those succumbing to SIDS or other causes. We recommend that these determinations be routinely performed whenever the gross autopsy findings are insufficient to explain the death.  相似文献   
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This study examines public opinion in Costa Rica and El Salvador regarding regional integration in Central America. Recent efforts at regional integration as well as the response of the governments of the above countries to those efforts are reviewed. Public opinion toward regional integration is significantly more positive but less structured in El Salvador than in Costa Rica. Differences in the international and domestic contexts help to explain the differential responses in these two countries. Likewise, contextual factors help to account for differences between Central American and European publics in attitudes toward regional integration. Charles L. Davis is associate professor of political science at the University of Kentucky. His interests are Latin American politics and comparative political behavior. Matthew J. Gabel is assistant professor of political science at the University of Kentucky. His interests are European politics and the politics of regional integration. Kenneth M. Coleman is a former professor at the University of Kentucky, the University of North Carolina-Chapel Hill, and the University of New Mexico. His interests are Latin American politics and public opinion.  相似文献   
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