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771.
The ages at which the maxillary and mandibular teeth of 121 boys and 111 girls reached 14 mineralization stages were determined from serial cephalograms at the Burlington Growth Centre. The present data are more comprehensive than any previously available and can be applied to chronological age determinations in juveniles of indefinite age, and of specimens in anthropological and forensic investigations. The sexes differed in the age at which they attained the stages of mineralization, with the canines demonstrating the greatest difference. In each sex, the ages at identical stages were similar for the corresponding teeth in the maxilla and mandible. Variability in age was greater among the males, especially for the first premolars, and increased with age, except for the third molars. Variability in age of third molar mineralization was greater in females and diminished among both sexes at late stages of root formation.  相似文献   
772.
Abstract: This article examines the way the European Community defends its interests in food safety matters within the Codex Alimentarius Commission. It shows that the European Community has strengthened its position as a policymaker within the Codex Commission. It also describes how the European members of the Codex Commission engaged (with mixed results) in the defence of certain principles typical of European food policy. These controversial principles are the precautionary principle, the need to consider factors other than science in determining food standards, and the need to label and make traceable food derived from biotechnology. Lastly, the article evaluates the function of the Codex Commission. Since, in at least two cases the discussions within the Codex Commission did not prevent WTO litigation, the value of the Codex Commission may be questioned. However, the overall assessment of the Codex Commission's activity is positive, since it provides an important and not easily replaceable forum to debate food safety issues, which are particularly sensitive for Codex members of the European Community.  相似文献   
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775.
Can political actors use rational strategies for political conflict when established institutions are unavailable to structure political choices because the institutions are themselves among the contested issues? In Soviet politics from 1985 to 1991, cross-cutting cleavages placed in question the possibility of any stable outcome. We argue that a multi-dimensional issue space was reduced to a single dimension, along which Mikhail Gorbachev could temporarily occupy a median, by the interaction between Gorbachev's own rhetoric and rhetorical tactics used by leaders of his nomenklatura opposition, by Boris Yeltsin as the leader of the democratic opposition, and by single-issue groups called neformaly. The match between these four players' rhetorics and the four strategic options identified by a simple spatial model offers empirical evidence that rational strategies were available despite institutional flux.  相似文献   
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777.
The dependence of postmortem blood-drug concentrations on the collection site and on the postmortem interval before specimen collection has been studied. These studies consisted of both sequential sampling from the same collection site at defined time intervals and a comparison of the drug concentrations of postmortem blood simultaneously collected from various sites. A site and time dependence was observed for postmortem blood-drug concentrations. The heart blood-drug concentrations were, in general, significantly higher than those of peripheral specimens. As a result of this phenomenon, the analysis of peripheral blood specimens and solid tissues is often necessary before a definitive interpretation of postmortem toxicological analyses is possible.  相似文献   
778.
Six red blood cell (RBC) antigen systems, coupled with human lymphocyte antigen (HLA) phenotyping, were used to establish paternity on 28 mother/child/alleged-father trios. Samples were subsequently examined using the deoxyribonucleic acid (DNA) fingerprinting test with the multilocus Jeffreys DNA probes 33.6 and 33.15. In 27 of 28 paternity cases, the DNA fingerprinting test results supported and enhanced the results of RBC and HLA typing by resolving disputed paternity cases conclusively. One discrepancy between conventional serological methods and DNA analysis is discussed.  相似文献   
779.
This paper investigates the dynamics of vote intention for the Danish and Norwegian Progress Parties. It shows that support patterns for these populist parties can be explained with similar independent variables. These include national economic conditions and political events. Empirical support for the usefulness of these variables is stronger in the case of the Danish Progress party. The analysis also suggests that increases in support for both parties during the 1980s was to a significant extent driven by the increase in the number of foreigners entering these countries.  相似文献   
780.
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