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871.
872.
Assessing hypostasis by colorimetry.   总被引:2,自引:0,他引:2  
  相似文献   
873.
874.
This study examines the utility of moving beyond a simple "on–off" dichotomous view of contiguous land borders. For each of the 301 contiguous land borders between states in the international system, measures of ease of interaction, salience, and overall border "vitalness" have been developed using Geographical Information Systems technology. These variables are used to test two major extant lines of thought in international relations literature, as well as our proposed alternative, regarding the expected effect of the "nature" of borders on interstate behavior. We conclude not only that the "nature" of contiguous borders matters but also that the relationship between each of the three border measures and the likelihood of conflict is curvilinear concave—with both high ease of interaction and high salience related to lower levels of conflict, and the middle range of both variables related to higher levels of conflict.  相似文献   
875.
876.
877.
A 3-year-old child died of the combined effects of a bacterial superinfection and a relative overdose of hydrocodone prescribed for a cough due to a presumed viral respiratory tract infection. This case illustrates the importance of evaluating the effects of prescribed medication in assessing the cause and mechanism of death in children dying suddenly of presumed natural disease.  相似文献   
878.
Abstract: To determine the prevalence and circumstances of psychoactive substances amongst nonoverdose completed suicide, 1436 consecutive cases autopsied at the NSW Department of Forensic Medicine over the period 1/1/1997–12/31/2006 were analyzed. Substances were detected in 67.2% of cases, and illicit drugs in 20.1%. Alcohol was present in 40.6% of cases. Males were more likely to be positive for alcohol, cannabis, and psychostimulants, and females for pharmaceuticals. Illicits were associated with younger age. Alcohol was most prominent amongst toxicity cases, as were opioids, psychostimulants amongst gunshot cases, and pharmaceuticals amongst drownings. Cases in which drug and alcohol histories were noted were more likely to have a substance detected. Alcohol was more common where a suicide note was left and where relationship problems were involved. Pharmaceuticals were more common where a previous attempt was noted. Licit and illicit substances are strongly associated with suicide, even when the method does not involve drug overdose.  相似文献   
879.
Hair samples were contaminated by rubbing with cocaine (COC) followed by sweat application, multiple shampoo treatments and storage. The samples were then washed with isopropanol for 15 min, followed by sequential aqueous washes totaling 3.5 h. The amount of drug in the last wash was used to calculate a wash criterion to determine whether samples were positive due to use or contamination. Analyses of cocaine and metabolites were done by LC/MS/MS. These procedures were applied to samples produced by a U.S. government-sponsored cooperative study, in which this laboratory participated, and to samples in a parallel in-house study. All contaminated samples in both studies were correctly identified as contaminated by cutoff, benzoylecgonine (BE) presence, BE ratio, and/or the wash criterion. A method for determining hair porosity was applied to samples in both studies, and porosity characteristics of hair are discussed as they relate to experimental and real-world contamination of hair, preparation of proficiency survey samples, and analysis of unknown hair samples.  相似文献   
880.
The Nature of Managerial Work, 2nd edition. By Henry Mintzberg . Engle‐wood Cliffs, N.J.: Prentice‐Hall.  相似文献   
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