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901.
Bile is, in certain cases, collected together with blood from different sites (heart, brain, femoral), urine and other organs or matrices. This study reports comparative results obtained from the analysis of blood and bile for different drugs found: acetaminophen, amphetamine and related compounds, several antidepressants, several benzodiazepines, cocaine and its metabolites, dextropropoxyphene and its metabolite, hydroxyzine, methadone and metabolite, morphine and codeine, levomepromazine, thioridazine, propranolol, tramadol and its metabolite. Several findings are presented: (1) There were no significant differences in the levels of the compounds among the samples of blood obtained from different sites. (2) Levels in bile are generally several fold higher than those in blood. The mean bile to blood ratios vary from about 1 (for acetaminophen, amphetamine) to about 2000 (for desmethylclobazam). (3) In certain cases (16 over 44), although the drug or its metabolite was not detected in blood from different sites, it was detected in bile. As other authors had advocated, it is very useful to ask the pathologist to take the gall bladder with its contents together with the other samples, in order that the sample of bile can be used in the comprehensive toxicological analysis and therefore be complementary to the other fluids or matrices. An additional advantage for using bile is that the concentrations of drugs or their metabolites are generally several fold higher than their blood concentrations.  相似文献   
902.
Time-of-flight mass spectrometry (TOF-MS) offers new perspectives for forensic toxicology. Qualitative and quantitative analyses of a mixture of three selected benzodiazepines (diazepam, nordazepam and bromazepam) were used to compare gas chromatography (GC-TOF-MS, quadrupole GC-MS, GC-ECD) and liquid chromatography (HPLC-DAD) data. Method validation parameters like LOD, LOQ, S/N-ratios reflect the capabilities of GC-TOF-MS. Five-point calibrations for bromazepam in human peripheral blood (50, 100, 160, 200, 300 ng/ml) using medazepam as internal standard (1000 ng/ml) were performed. The calibrations using GC-TOF-MS (using the fragments of m/z 236 and 288), GC-ECD (dual system) and HPLC-DAD (at 235 nm) all showed correlation coefficients close or superior to 0.99. Quadrupole GC-MS data was not used in the comparison of extracted samples due to the low sensitivity in the full scan mode. Two analyses of real cases concerning bromazepam are presented. In the first case, the presence or absence of bromazepam could not be established with both HPLC-DAD and GC-ECD due to background signals. The extracted ion chromatograms and spectrum traces after the analysis with the GC-TOF-MS could clearly excluded the presence of bromazepam. The second case illustrates the quantitation of bromazepam, where both HPLC-DAD and GC-ECD were unable to give satisfactory results, again due to interfering background signals. The analyses performed on the GC-TOF-MS-system demonstrated high sensitivity and also high selectivity due to the high quality of mass spectra obtained. The advantages of GC-TOF-MS make it a promising analytical technique for forensic toxicology.  相似文献   
903.
Child death due to repeated episodes of physical assault or neglect has been termed the child abuse-maltreatment syndrome (CAMS). We characterized the injuries in a series of fatally abused or maltreated child to delineate objective diagnostic criteria for the CAMS for use by clinicians and pathologists. All deaths (age <17 years) investigated by the Office of the Chief Coroner for Ontario, Canada during the time period 1990-1995 were reviewed. Cases of CAMS were defined as death due to lethal recent injury or malnutrition in the presence of significant old (healing or healed) injuries indicative of repeated episode of inflicted trauma. The nature and frequency of the various injuries was determined. The frequency of the shaken baby syndrome, and the types and frequency of ano-genital injuries were also studied. Twenty-one cases of fatal CAMS were found in the study period. Most cases had significant recent head injury with intra-cranial hemorrhage (71%). Other significant recent injuries commonly observed included blunt injuries of the skin and soft tissues (67%), blunt abdominal trauma with visceral injuries (14%), and fractures (18%). Eight cases (38%) fulfilled accepted criteria for the shaken baby syndrome. Many children with fatal head injuries had evidence of older head trauma (38% of all cases). A significant minority of cases had evidence of malnutrition due to neglect (10%) or ongoing ano-genital injuries (10%). Most cases of child homicides due to repeated episodes of abuse or maltreatment involve head trauma including shaken baby syndrome. Fractures of long bone and ribs, the classical markers of child abuse, were relatively infrequent compared with head injury. A proportion of cases had ano-genital injuries due to repeated sexual abuse or punitive maltreatment. All clinicians and pathologists must recognize the wide spectrum of injuries in child abuse to ultimate protect the victim or other children in an at-risk situation.  相似文献   
904.
This study examined the ability of future certainty—an individual's perception of future stability, operationalized as the likelihood of certain life outcomes–to explain variance in delinquency and school adjustment, while controlling for economic, neighborhood, and family factors, among a cross-sectional sample of 1422 male and 1562 female African American adolescents drawn from the National Longitudinal Study of Adolescent Health (Add Health). Three kinds of future certainty were examined: future life certainty (e.g., life expectancy), marriage certainty, and college certainty. In hierarchical multiple regression analyses, future certainty and family functioning were stronger predictors than economic and neighborhood variables: neighborhood disorganization and family socioeconomic status. Future life certainty and expectations of attending college were stronger predictors of delinquency among males than females. Marriage certainty was the weakest predictor of the three certainty variables.  相似文献   
905.
The role of interpersonal sensitivity in the relation between romantic stress and depression was examined in 55 adolescent girls from an inner-city high school. Depression, interpersonal sensitivity, and chronic and episodic romantic stress were measured at two time points, 6 months apart. Interpersonal sensitivity was found to moderate the longitudinal relation between romantic stress (both chronic and episodic) and depression. In contrast, interpersonal sensitivity did not potentiate depressive responses to non-romantic interpersonal stress, suggesting particular importance of stress in the romantic domain for adolescent girls. Results indicate that girls' sensitivities to romantic relationship stress should be specifically addressed in depression prevention and intervention programs.Received her PhD from the University of Southern California. Research interests include the influence of romantic relationship factors, such as romantic stress and dating violence, on the development of depression during adolescence.Received her PhD from the University of California, Los Angeles. Research interests include the interplay between adolescent depression, personality disorder symptoms, and interpersonal variables including adjustment in friendships and romantic relationships.Research interests include cognitive and interpersonal factors in adolescent depression.  相似文献   
906.
The investigation involved the assessment of a model predicting that family and university relationship environments are linked with identity processes and identity states (statuses) that predict psychosocial resources among first-year university students. A sample of 351 university students, between the ages of 18 and 21 years, completed measures of psychosocial maturity based on Erikson's notions of ego virtues, a measure of identity processing styles (diffuse-avoidant, normative, and information styles), identity statuses (diffusion, foreclosure, moratorium, and achievement), measures of family climate (conflict, expression, cohesion), and assessments of university relationships with faculty, advisors, and students. Based on linear structural equations, the model, with some adjustments, had a good fit with the data and demonstrates the complex association between perceived family and school climate, identity formation, and the association with psychosocial resources. The investigation demonstrates how multivariate model testing can be completed to assess some of the complexity suggested by Erik Erikson regarding identity formation. Gerald R Adams is a Professor of Family Relations and Human Development at the University of Guelph in Ontario, Canada. His major interests focus on family relations, identity development, education, and prevention. Michael Berzonsky is Professor of Psychology at State University of New York at Cortland, New York. His major interests are identity styles, social cognition, and adolescent development. Leo Keating is a data analyst at the University of Guelph.  相似文献   
907.
The association of pubertal maturation with internalizing and externalizing symptoms was examined with a sample of 867 African-American 10 – 12-year-old children. Children reported their pubertal development status and timing using a self-report questionnaire, and symptoms were assessed through diagnostic interviews with the children and their primary caregivers. Pubertal status and timing were significantly associated with children's reports of the internalizing symptoms of social anxiety disorder, generalized anxiety disorder, and major depression and with the externalizing symptoms of oppositional defiant disorder, attention deficit disorder, and conduct disorder. Pubertal development also was associated with caregivers’ reports of children's externalizing symptoms. The pubertal transition was associated with internalizing and externalizing symptoms in both boys and girls.Xiaojia Ge is Professor at the University of California, Davis. He received his PhD in sociology from the Iowa State University. He is interested in the influences of biological changes and social transitions on emotional and behavioral development in children and adolescents.Gene H. Brody is a Regents’ Professor at the University of Georgia. He received his PhD in developmental psychology from the University of Arizona. His major research interests are contextual influences on cognitive and psychosocial development, particularly those factors that protect at-risk children and adolescents from negative outcomes.Rand. D. Conger is Professor at the University of California, Davis. He received his PhD in sociology from the University of Washington in Seattle. He is interested in the influences of family economic stress on emotional and behavioral adjustment of family members. He is currently conducting a large-scale study on Mexican American families in California.Dr. Ronald L. Simons is Distinguished Research Professor at the University of Georgia. He received his PhD in sociology from Florida State University. Much of his research has focused upon the manner in which family and community processes combine to influence child development. He has also been concerned with the effect of discrimination and racial socialization upon child adjustment.  相似文献   
908.
Existential anxiety is hypothesized to be a core human issue in a great deal of theoretical and philosophical writing. However, little is known about the emergence of these concerns and their relation to emotional functioning in youth. The purpose of this study was to examine the phenomenon of existential anxiety in a sample of adolescents. Data on existential concerns, identity development and psychological symptoms were collected on a sample of 139 youth in grades 9–12. Results indicated that existential anxiety concerns have a theoretically consistent factor structure, are common among adolescents, and are associated with psychological symptoms, as well as identity issues. Results are discussed with regard to the importance of existential concerns in the lives of youth and the need for additional research.Received PhD from Florida International University. Interests are identity development including associated anxiety and distress, cross-national comparisons, and the development of identity interventions.Received PhD from Florida International University. Interests focus on the developmental psychopathology of anxiety and depression.Received PhD from the University of Arizona. Interests include a range of topics in developmental psychopathology, prevention, program evaluation, and research methodology.  相似文献   
909.
910.
The relation between elections and the economy in Latin America might be understood by considering the agency of candidates and the issue of policy preference congruence between investors and voters. The preference congruence model proposed in this article highlights political risk in emerging markets. Certain risk features increase the role of candidate campaign rhetoric and investor preferences in elections. When politicians propose policies that can appease voters and investors, elections may have a limited effect on economic indicators, such as inflation. But when voter and investor priorities differ significantly, deterioration of economic indicators is more likely. Moreover, voter and investor congruence is more likely before stabilization, when an inverted Philips curve exists, as opposed to following stabilization, when a more traditional Philips curve emerges.  相似文献   
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