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91.
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
92.
93.
C Moore S Browne I Tebbett A Negrusz W Meyer L Jain 《Forensic science international》1992,56(2):177-181
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
94.
Michelle Wierson Sarah D. Nousiainen Rex Forehand Amanda McCombs Thomas 《Journal of family violence》1992,7(1):9-18
Much attention has been paid to the nature of parent-adolescent relationships, with a frequent conclusion being that it is a time of marked disagreement between parents and their adolescents. However, other literature suggests that this time is not inherently conflictual. The purpose of this study was to examine agreement and disagreement between mothers, fathers, and adolescents on specific issues. Then, adolescent adjustment was assessed, and the degree to which it was a function of congruence with parents was examined. A modified version of the Issues Checklist was used to measure intrafamily agreement; the Revised Behavior Problem Checklist and the Harter Scale of Child's Actual Competence were completed by adolescents' social studies teachers to assess adolescent functioning. Relative to their parents, adolescents reported that they should make more decisions alone, while both mothers and fathers reported that decisions should be made jointly among all family members. Only father-adolescent congruence was found consistently to be related to adolescent functioning. Possible explanations for the present results and relevant issues pertaining to family agreement are discussed. 相似文献
95.
Editors Note: This commentary touches on an aspect of technology transfer to the Third World that often is neglected: Can
the technology recipients afford to use it? Although the authors focus on the economics of shrimp production by subsistence
farmers, affordability is one of the major concomitant issues of transfer from developed to developing countries. 相似文献
96.
D M Fox 《Journal of health politics, policy and law》1990,15(2):341-355
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
97.
98.
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
99.
C J Kim B H Kwak S D Kim S P Kim 《The American journal of forensic medicine and pathology》1992,13(3):211-213
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
100.