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61.
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   
64.
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   
65.
The primary aim of this paper is to review the literature on preadolescent friendships in order to examine the relationship between preadolescent friendships and social support in adulthood. Social supports are important to health, both directly and as a stress buffer. Few studies, however, have specifically examined adult social supports from the perspective of their developmental precursors and critical developmental periods. Some data indicate that the preadolescent period may be of particular importance to the development of adult social skills and ties. Observational and empirical studies of preadolescent peer relationships, and in particular best friendships, suggest unique and critical contributions to adult social relatedness. Present research is suggestive but is insufficient to validate preadolescence as a critical period in adult social relatedness. Our review has implications for better understanding the mechanisms by which preadolescent friendships effect adult social support—an important mediator of the effects of stress on health. Further longitudinal study is needed.Received Ph.D. from University of Maryland. Research interests are social supports and psychological responses to trauma and disaster.Received M.D. from Yale University. Research interests are social supports and traumatic stress.  相似文献   
66.
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   
67.
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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69.
Observations of high velocity bloodspatter on adjacent objects   总被引:1,自引:0,他引:1  
In a recent homicide investigation, high velocity backspatter was observed on the sleeve cuff of the accused. These minute droplets were discovered only after microscopic examination and were limited in number. A study was initiated to determine if these were truly backspatter droplets or transferred blood produced from light contact with a bloody item. It was observed that the backspattered blood was primarily limited to contact or near contact shots. An exception was a shot into an already bloody surface. It was found that backspattered blood would deposit on the shooter's shirt sleeve irrespective of the weave pattern. Transferred blood was observed only on the fiber tops. This information was found to be useful in reconstruction of events in suicides as well as possible homicides.  相似文献   
70.
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