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971.
A simple method for analyzing nitrite in urine has been developed to confirm and quantify the amount of nitrite in potentially adulterated urine samples. The method involved separation of nitrite by capillary electrophoresis and direct UV detection at 214 nm. Separation was performed using a bare fused silica capillary and a 25 mM phosphate run buffer at a pH of 7.5. Sample preparation consisted of diluting the urine samples 1:20 with run buffer and internal standard, and centrifuging for 5 min at 2500 rpm. The sample was hydrodynamically injected, then separated using -25 kV with the column maintained at 35 degrees C. The method had upper and lower limits of linearity of 1500 and 80 microg/mL nitrite, respectively, and a limit of detection of 20 microg/mL. The method was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) protocol (Document EP10-A2), and validated using controls, standards, and authentic urine samples. Ten anions, ClO-, CrO4(-2), NO3-, HCO3-, I-, CH3COO-, F-, SO4-, S2O8(-2), and Cl-, were tested for potential interference with the assay. Interferences with quantitation were noted for only CrO4(-2) and S2O8(-2). High concentrations of Cl- interfered with the chromatography. The method had acceptable accuracy, precision, and specificity.  相似文献   
972.
This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy.  相似文献   
973.
Suppression of environmental science   总被引:1,自引:0,他引:1  
  相似文献   
974.
Sudden unexpected death in an infant caused by or associated with neoplasm is rare. We describe a case of a sudden death in an apparently healthy 3-month-old female, in which the autopsy revealed a multiple type II infantile hepatic hemangioendothelioma (IHE). This uncommon tumor has, untreated, a relatively high mortality rate, mainly due cardiac failure resulting from massive arteriovenous shunts, but the association with sudden infant death is very rare.  相似文献   
975.
Criminologists increasingly have studied the effects of criminal justice contact on a broad range of offenders' adult outcomes. However, virtually all of this research focuses exclusively on street-level offenders. With the use of a unique data set that includes street-level and white-collar offenders, we investigated the odds of regaining steady employment following criminal justice contact by offender type. Specifically, we investigated the effects of age of onset, number of prior arrests, total time sentenced, timing of first arrest, and timing of first incarceration on employment stability for both types of offenders, while controlling for family background factors, race, educational attainment, and age. Overall, we found that white-collar offenders are better able to rebound following contact with the criminal justice system. However, when the accrue multiple arrests and are arrested or incarcerated before the age of 24, white-collar offenders face the same obstacles to employment stability as their street-level counterparts.  相似文献   
976.
This study examined whether sexual abuse was related to higher levels of psychological distress among incarcerated youth and if the effects were invariant across gender. Participants were male and female adolescents, aged 11 to 20 years, incarcerated in six juvenile correctional institutions in five states. Using data from a national study of juveniles confined to secure institutions, this study assessed the relationship between gender, sexual abuse, and depression. Adolescents who were sexually abused during childhood compared to adolescents who were not report higher levels of depression. Sexually abused girls and boys report higher levels of depression compared to boys not sexually abused. These findings suggest the importance of understanding the relationship between childhood sexual abuse and depressive symptoms among incarcerated youth. Additionally, the findings suggest that the effects of childhood sexual abuse are similar for males and females among a high-risk sample of institutionalized juvenile delinquents. Implications for treatment of incarcerated youth are discussed.  相似文献   
977.
978.
A total of 137 urine samples and 46 serum samples, corresponding to 154 self-confessed designer drugs consumers in Ibiza island, were analyzed for the presence of designer drugs: amphetamine and amphetamine derivatives (methamphetamine, methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine (MDEA), methylenedioxyamphetamine (MDA), p-methoxymethylamphetamine (PMMA), p-methoxyamphetamine (PMA), etc.), ketamine and gamma-hydroxybutyric acid. Among this population, coming both from the forensic clinic and from the emergency room of a hospital, a total of 99 cases were found positive for some designer drug. This study shows the prevalence of methylenedioxymethamphetamine (MDMA) among designer drug users, sole or in association with other drugs. Also, the mixture of MDMA with other designer drugs, ethanol and/or cocaine is shown to be more likely to produce toxic symptoms requiring clinical attendance in a hospital emergency room. These findings along with the consumption history, the concentrations of drugs and metabolites in urine and serum and the toxicological significance for the interpretation of some MDMA metabolites such as 4-hydroxy-3-methoxymethamphetamine (HMMA) are discussed in this study.  相似文献   
979.
Downstairs falls frequently occur within domestic environments and are mainly associated with elderly and intoxicated individuals, often feature multiple injuries on various parts of the body. In most cases it is not possible to determine the cause of the fall and/or death solely by means of external examination. In this retrospective study, which covers a period of 11 years, all cases of death which included a fall downstairs in their case history, were collected from the Forensic Institutes of the Universities of Bonn and Greifswald, Germany. Falls downstairs made up to 2% (166 cases) of all postmortem examinations carried out within this period. Interestingly, almost double of the amount of such falls applied to males as to females. The primary cause of death was cranio-cerebral trauma and the vast majority of skull injuries associated with falls downstairs were found above 'the hat brim line'. Injuries were also often found on several other parts of the body at once. Nineteen of the 116 examined individuals exhibited agonal injuries. In these cases, postmortem examination revealed pre-existing disease or intoxication to be the cause of death and thus, cause of the fall. The injury pattern only allows a tendency towards vital or agonal incident as a conclusion.  相似文献   
980.
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