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861.
Oral fluid is an interesting alternative matrix for drug testing in many environments, including law enforcement, workplace drug testing, and drug treatment facilities. Performance characteristics of the FDA-cleared, qualitative, Cozart RapiScan Opiate Oral Fluid Drug Testing System (Opiate Cozart RapiScan System or Opiate CRS) were compared to the semi-quantitative Cozart Microplate EIA Opiate Oral Fluid Kit (Opiate ELISA) and to gas chromatography/mass spectrometry (GC/MS). The following oral fluid opiate cutoffs were evaluated: the GC/MS limit of quantification (LOQ) of 2.5 mg/l; 15 microg/l currently used for oral fluid testing in the United Kingdom (UK); 30 microg/l (Opiate CRS cutoff); and 40 microg/l, the proposed Substance Abuse and Mental Health Services Administration (SAMHSA) cutoff. Subjects provided informed consent to participate in this IRB-approved research and resided on the closed research ward throughout the study. Three oral codeine doses of 60 mg/70 kg were administered over a 7-day period. After a 3-week break, subjects received three doses of 120 mg/70 kg within 7 days. Oral fluid specimens (N = 1273) were analyzed for codeine (COD), norcodeine (NCOD), morphine (MOR) and normorphine (NMOR) by GC/MS with an LOQ of 2.5 microg/l for all analytes. MOR and NMOR were not detected in any sample; 26.5% of the specimens were positive for COD and 13.7% for NCOD. Opiate CRS uses a preset, qualitative cutoff of 10 microg/l; this is equivalent to 30 microg/l in undiluted oral fluid as the oral fluid collection process involves a 1:3 dilution with buffer. Sensitivity, specificity, and efficiency of Opiate CRS compared to Opiate ELISA were 98.6, 98.1, and 98.2% at a 30 microg/l cutoff and 99.0, 96.2, and 96.6% at a 40 microg/l cutoff. Compared to the much lower GC/MS LOQ of 2.5 microg/l, sensitivity, specificity and efficiency were 66.8, 99.3 and 90.7%. Increasing the GC/MS cutoff to the current UK level yielded performance characteristics of 81.5% (sensitivity), 99.3% (specificity), and 95.4% (efficiency). Using a GC/MS cutoff identical to the preset Opiate CRS cutoff yielded sensitivity, specificity, and efficiency of 88.5, 99.2, and 97.5%, respectively. At the proposed SAMSHA confirmation cutoff of 40 microg/l, sensitivity increased with little change in specificity and efficiency (91.3% sensitivity, 98.9% specificity, and 97.5% efficiency). Oral fluid is a suitable matrix for detecting drugs of abuse. Opiate CRS, with a 30 microg/l cutoff, is sufficiently sensitive, specific and efficient for oral fluid opiate analysis, performing similarly to Opiate ELISA at the same cutoff, and having performance characteristics >91% when compared to GC/MS at the proposed SAMHSA cutoff.  相似文献   
862.
863.
The North Korean nuclear standoff has escalated since North Korea let slip that it was developing nuclear weapons while James Kelly, U.S. Assistant Secretary of East Asian and Pacific Affairs, was visiting Pyongyang in October 2002. The Bush administration has acknowledged that the United States will not discount a preemptive military strike on the suspected nuclear development facilities, and North Korea has stood firm against any pressure to halt its nuclear development from the international community. Dialogue and meetings for international cooperation among the major countries concerned, including Korea, the U.S., Japan and China, have been activated to resolve the nuclear crisis in the Korean Peninsula, especially after the U.S. pronounced an end to its war against Iraq in early May of this year. In the middle of the rapidly changing situation on the Korean peninsula, the inter-Korean reconciliation and cooperation initiated by the Sunshine Policy of the Kim Dae Jung administration and followed by the Roh Moo-hyun administrations Policy of Peace and Prosperity are not separable from the nuclear situation. This paper follows recent developments of inter-Korean relations, illustrates South Koreas stance on the issue and suggests the EUs role on the nuclear issue. This is a revised version of the paper presented at the Asia-EU Journalists Seminar organized by the Asia Europe Foundation and the Korea Press Foundation (KPF), held in Brussels, Belgium, May 22 2003. Financial support from the KPF is gratefully acknowledged.  相似文献   
864.
One in five Aboriginal people enrolled in a Vancouver study of people who inject drugs became HIV-positive over a five-year period ending in May 2001. This is twice the rate among non-Aboriginal people in the study.  相似文献   
865.
Many burn injuries are mistakenly referred to as "accidents" because they occur suddenly and seem unpredictable and uncontrollable; however, injuries often occur in predictable patterns. We reviewed all pediatric forensic cases referred to the Medical University of South Carolina Forensic Pathology Section over a 28-year period from January 1975 to December 2002. There were 124 cases with 121 fire-related fatalities and three scald fatalities. Ninety of the burn victims were in the 0-5-year age group. The manner of deaths showed 108 accidents and 12 homicides (four undetermined). Eleven of 12 burn-related homicides occurred at the home with all of the victims in the 1-8-year age group. The perpetrator of the home fire homicides was the mother in five cases and the sister in one case (two undetermined). Homicide involved a vehicle fire in one case in which the father caused an explosion with an accelerant. The three scald death perpetrators were the father, mother's boyfriend, and an aunt.This retrospective study and review of the literature may reveal patterns useful for evaluation of manner of death. By recognizing scene characteristics, potential perpetrators, and children at risk, we can better classify pediatric burn-related fatalities.  相似文献   
866.
The mandible is the largest and hardest facial bone and retains its shape better than other bones in the forensic and physical anthropologic field. The mandible can be used to distinguish among ethnic groups and between sexes. We examined the morphological characteristics of the mandibles of 102 Koreans of either sex. Of 13 nonmetric items of the mandible, the characteristic that best allowed the sexes to be distinguished was the contour of the lower border of the mandible: rocker-shaped mandibles predominated in males (68.1%), whereas most females (84.6%) exhibited a straight mandible. In addition, the mental region was shaped differently between the sexes: the shape of the chin in most males was generally bilobate or square (91.7%), whereas the chin in females was either square (45.5%) or pointed (54.5%). In this study, the positive predict values of male and female were 92.5% and 73.7%, respectively. Therefore, the nonmetric method used to analyze the mandible in this study can be used for sex discrimination.  相似文献   
867.
Pregnancy-related death is defined by the International Classification of Diseases, Tenth Revision (ICD-10) as the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the cause of death. In the year 2000, a collaborative effort involving World Health Organization (WHO), UNICEF, and UNFPA estimated 660 maternal deaths in the United States. This averages 11 maternal deaths per 100,000 live births reported. Many pregnancy-associated deaths are not easily identified as such since the presence of a recent or current pregnancy may not be listed on the death certificate. Thus, the WHO estimates that in the United States, the maternal mortality is approximately 17/100,000 pregnancies. This is significantly higher than the goal set by the US Department of Health and Human Services in Healthy People 2010, which sets the target for maternal mortality at less than 3.3/100,000 live births. The most common causes of maternal death vary somewhat from region to region in the United States. They include pulmonary thromboembolism, amniotic fluid embolism, primary postpartum uterine hemorrhage, infection, and complications of hypertension including preeclampsia and eclampsia. Pulmonary disease, complications of anesthesia, and cardiomyopathy also are significant contributors to maternal mortality in some populations. The death of a pregnant or recently pregnant individual poses a wide scope of challenges to the forensic pathologist and investigator. The pathologist must have a broad knowledge of the physiologic and biochemical changes that occur during pregnancy, as well as the clinical and pathological manifestation of these changes. Conditions that may be "benign" in the nonpregnant individual may be lethal in the puerperal period. In addition, it should be kept in mind that deaths during pregnancy may be due to unnatural causes. Accident, homicide, and suicide must be ruled out in each case. The authors reviewed all forensic cases referred for autopsy to the Forensic Section of the Medical University of South Carolina from January 1989 through December 2003. All decedents listed as pregnant or postpartum were analyzed as to maternal age, race, past medical history, previous pregnancies and outcome, prenatal care, gestational age, fetal or neonatal outcome, location of delivery, placental findings, maternal autopsy findings, toxicology, cause of death, manner of death, and fetal or neonatal autopsy findings. The authors present this retrospective study to better determine the factors leading to maternal demise and discuss the autopsy/ancillary techniques useful in determining the cause of death in this challenging area.  相似文献   
868.
Organic impurities of methamphetamine may show different patterns by synthesis. In the present study, we tried to find the impurities reflecting the conditions of synthesis by comparing impurity patterns of the methamphetamine samples synthesized by different methods. Sixteen methamphetamine samples were synthesized from ephedrine and pseudoephedrine by the three different manufacturing methods of Emde, Nagai and Moscow. The synthesized samples were extracted with ethyl acetate containing four internal standards, and the patterns of the organic impurities were investigated by GC-MS and GC-FID . Through the investigation, we found 10 peaks appearing in the latter part of GC chromatograms are characteristic to synthesis. The areas of the selected peaks were converted to the variables suitable for the statistical calculation, and the synthesized samples could be classified into four groups through the resultant cluster analysis.  相似文献   
869.
870.
Zhang Y  Xu Q  Cui H  Cui Y  Lin H  Kim K  Lee J 《Forensic science international》2005,151(2-3):299-301
Sequence polymorphism of the mitochondrial DNA (mtDNA) control region, hypervariable regions HVR I, II and III, from 55 unrelated Korean ethnic group individuals from northeast China (YanBian area) were determined by PCR amplification and cycle sequencing.  相似文献   
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