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71.
A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.  相似文献   
72.
A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers.  相似文献   
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B. C. Koh 《East Asia》1994,13(2):61-74
North Korea’s foreign policy track record in the post-cold war era is mixed. Most notable setbacks are the diplomatic normalization between the Soviet Union (now Russia) and South Korea; the reversal of its UN policy that paved the way for the simultaneous admission of the two Korean states to the world organization; and the diplomatic normalization between China and South Korea. On the credit side of Pyongyang’s diplomatic ledger are changes in its relations with Tokyo and Washington. While tangible results have yet to materialize, particularly in North Korea-Japan relations, the groundwork has nonetheless been laid for significant improvement. North Korea’s suspected nuclear weapons development program has played a major role in the unfolding of its relations with the United States. Conceptually, North Korean foreign policy can be explained in terms of its quest for three interrelated goals: security, legitimacy, and development. In the post-cold war era security appears to have emerged as the most important of the three goals. North Korea is at a crossroads. The choices it makes in foreign policy will determine not only the direction of its domestic policy but, ultimately, the survival of the regime itself. The external players in Seoul, Washington, Tokyo, Beijing, Moscow, and Vienna (the IAEA) have varying degrees of leverage over Pyongyang’s policy as well.  相似文献   
76.
A 22-year-old Korean soldier, who had received blows to the neck and epigastrium from an officer 10 h earlier, suddenly died after massive hematemesis. He had been in relatively good health except for episodes of blood-tinged vomiting approximately 5 and 7 months prior to this event. Postmortem examination revealed angiodysplasia involving the gastroesophageal junction, and the stomach was distended with blood. No abnormal findings were present around the whole viscera, and the duodenum was free of blood. The pathologic significance of upper gastrointestinal angiodysplasia as a potential source of bleeding and a chronologic correlation between the trauma and bleeding are discussed.  相似文献   
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This methodological paper presents the utility of survival analysis methods to provide age adjustment in the analysis of domestic violence data. These methods improve the estimation of lifetime probability of domestic violence, improve identification of patterns of first victimization over the lifespan, and provide methods of testing risk factors for first victimization while adjusting for the respondents' age. Most importantly, these methods allow a new investigation of recall bias. Results suggest that lifetime probability of abuse may have been substantially underestimated in previous studies because of problems in recall/disclosure encountered by middle-aged women.  相似文献   
78.
CROOK  RICHARD C 《African affairs》1997,96(383):215-242
Why is that former dominant or single party regimes, especiallythose in Africa, have generally survived and even emerged strengthenedafter the introduction of multi-party competitive elections?In Côte d'lvoire since 1990 the ruling party has beenable to win elections by using incumbency to present itselfas the organization most likely to be capable of putting togethera winning coalition. In a society segmented by a multiplicityof cultural and religious divisions and where political poweris a zero-sum game, the logic of democratic representation meansthat no group can afford to be excluded. Yet in the 1990 and1995 Ivorian elections .the opposition attacked die ethnic characterof the government and deliberately mobilized ethnic minorities,regional and religious (Islamic) sentiments. They thereforefailed to escape, in electoral terms, from their extremely localizedstrongholds. Their attempt to mobilize around an anti-foreignerplatform in 1990 rebounded in 1995 when the government itselftook over their ‘ultra-nationalist’ stance by excludingnon-Ivorians from the elections. The consequent exclusion ofthe opposition's favoured Presidential candidate and the failureof the opposition alliance to agree on a non-northern, non-Islamicalternative candidate led to a violent boycott and the eventualcollapse of the opposition alliance.  相似文献   
79.
Incarceration rates in the United States dramatically increased over the past several decades. This trend has drawn significant academic attention to prison overcrowding and its potential effect on inmate misconduct. The empirical relationship between inmate misconduct and overcrowding, however, is less than clear. To be sure, studies indicating positive, negative, and null relationships can all be found in the literature. The current research subjects this body of literature to a meta-analysis in an effort to: (1) clarify the direction and strength of the relationship between overcrowding and rates of prison misconduct across all studies, and (2) to uncover the degree to which variation in research outcomes can be attributed to methodological differences across studies. Results indicate that prison crowding has little substantive impact on inmate misconduct. Implications of the findings are discussed in detail.  相似文献   
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