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Although scholars focused on Soviet–American relations during the Cold War, the greatest number of conflicts for the U.S. occurred in the Third World, and most of these were with revolutionary states. Could U.S. policies toward the new revolutionary states have prevented the almost universal collapse in relations? Two dominant explanations for this breakdown are (1) American hostility toward revolutionary change and (2) Stephen Walt's variant of the spiral model. Using the comparative case approach and selecting "hard cases," this article disputes these explanations and offers a new theory based on the externalization of domestic conflict in the revolutionary states. Given their ideological goals, the radicals externalized their domestic conflicts with the moderates, who had transnational ties with the U.S., by fomenting tensions with Washington. To demonstrate that this theory can be generalized, this article varies the dependent variable and shows through a critical case that its lack of conflict can best be explained by the absence of the conditions that lead to externalization. The foreign policies of both the U.S. and revolutionary states are explained by classical realism as opposed to Walt's structural realism, which fails to account for the foreign policies of Third World states.  相似文献   
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This study examined the psychological impact of stalking upon female undergraduates, a population previously determined to experience a surprising stalking prevalence rate. Despite common understanding that stalking has deleterious effects, there have been no previous efforts to systematically assess them with standardized measures. Thirty-six female stalking victims were compared with 43 females who had been harassed and 48 controls. Psychological impact was assessed with the Posttraumatic Stress Disorder Scale, the Symptom Checklist-90-R, and the Self-Report Interpersonal Trust Scale. Stalked subjects endorsed significantly more PTSD symptoms and with greater severity than the harassed or control subjects. Stalked subjects also had significantly higher scores on several subscales of the SCL-90, and had significantly higher positive symptom totals and distress indices.  相似文献   
999.
In order to establish an animal model for entomotoxicological studies, the kinetics of morphine elimination from blood after a single intravenous injection of morphine and the concentration of morphine in tissues following a continuous perfusion were studied. The aim of these experiments was to obtain controlled morphine tissue concentrations similar to those encountered in fatal human heroin overdoses. These tissues can be used as a food source for developing fly larvae in entomotoxicological studies. In the single injection experiment, seven rabbits were administered 1 or 2 mg/kg body weight of morphine chlorhydrate via the main ear artery. Blood samples of 200 microL were removed regularly via a catheter. Morphine concentration was determined using RIA techniques. Morphine was found to be first rapidly distributed and then slowly eliminated, following a two-exponential equation. Elimination of morphine from blood can be described as a two-compartment model. Constants of the equation were determined using the Kaleidagraph program. Using those constants, the main pharmacokinetics parameters were calculated. Results of these parameters showed the following: clearance from 13.3 to 16.2 L.h.1, half-life of the distribution phase from 0.6 to 0.9 min, and half-life of the elimination phase from 21 to 26 min. These results were used to calculate the rate of perfusion of morphine for rabbits to obtain desired, controlled, and constant concentrations of morphine in tissues. In the second experiment, three rabbits received a perfusion of morphine intravascularly at a rate of 2 mg/kg/h for a period of 3 h. These rabbits were sacrificed and analyses performed on several abdominal and thoracic organs. Results showed that the concentrations of morphine differed according to the organ analyzed, but were reproducible for organs between animals. These concentrations were similar to those normally encountered in cases of human death due to heroin overdoses.  相似文献   
1000.
A study was undertaken to develop demographic, toxicologic, and pathological profiles of methamphetamine-related deaths. Anatomic and toxicologic findings in 413 deaths where methamphetamine was detected were compared with findings in a control group of 114 drug-free trauma victims. The number of cases per year did not change significantly over the course of the study. Mean age was 36.8 years, but 11% were over the age of 50. Decedents were overwhelmingly male (85.2%) and Caucasian (75%). Blood concentrations of methamphetamine and amphetamine were indistinguishable in cases where methamphetamine was related to the cause of death (MR) and cases where it was not (non-MR) (2.08 vs. 1.78 mg/L, p = 0.65, and 0.217 vs. 0.19 mg/L, p = 0.82). Coronary artery disease, ranging from minimal to severe multivessel, was identified in 79 of the 413 drug users, but in only six of the 114 drug-free controls (p = 0.0004), and MR decedents had enlarged hearts compared with controls. There were also ten cases of subarachnoid and intracranial hemorrhage in the MR group. Abnormalities of the liver (34%) and lungs (24.7%) were frequent. In 65% of these cases, death was due to accidental methamphetamine toxicity. In the remaining cases, methamphetamine was an incidental finding. We conclude that, in our jurisdiction, neither the rate of detection nor the number of methamphetamine deaths has increased significantly in the past 13 years. Decedents are almost all Caucasian males, and many were approaching middle-age. Methamphetamine use is strongly associated with coronary artery disease and with subarachnoid hemorrhage.  相似文献   
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