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The survival of the tiger (Panthera tigris) is seriously threatened by poaching to provide raw materials for traditional Chinese medicines (TCMs). Most highly prized are the tiger's bones, which are used in combination with other animal and plant derivatives in pills and plasters for the treatment of rheumatism and other ailments. Hundreds of patent remedies have been produced which claim to contain tiger bone, but proof of its presence is needed if legislation prohibiting the trade in endangered species is to be enforced.A highly sensitive tiger-specific real-time PCR assay has been developed to address this problem. Using primers specific to the tiger mitochondrial cytochrome b gene, successful amplification has been reliably achieved from blood, hair and bone as well as from a range of TCMs spiked with 0.5% tiger bone. Although capable of detecting fewer than 10 substrate molecules, the seven varieties of TCM pills and plasters tested showed no detectable trace of tiger DNA before spiking. Furthermore, sequencing several "tiger bone" fragments seized from TCM shops has shown that they actually originated from cattle and pigs. The potential effects of traditional bone preparation methods, evidence that much lower concentrations are used than alleged on TCM packaging, and substitution of bones from other species all suggest a low likelihood of detecting tiger DNA in patent medicines. Despite this, the basic methods have been thoroughly proven and can be readily applied to derivatives from other Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) protected species, providing a rapid and highly sensitive forensic test for species of origin. Potential applications to the monitoring of wild populations are demonstrated by the successful identification of shed hairs and faecal samples.  相似文献   
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The presence of the heroin metabolite 6-monoacetylmorphine (6-MAM) in urine is used to definitively identify recent heroin abuse. A rapid and sensitive GC-MS method for the simultaneous analysis of codeine, norcodeine, morphine, normorphine and 6-MAM in urine was developed and successfully applied to the analysis of 321 'heroin-positive' urine specimens from individual subjects (identified by the presence of 6-MAM), to provide quantitative urinary opiate excretion data for heroin abusers.The cohort analysed was composed of 238 males (age range 16-53 years) and 83 females (age range 16-50 years). The concentrations of free 6-MAM, morphine and codeine determined in these 321 specimens ranged between 103-246,312, 129-193,600 and 103-519,000 microg/l, respectively. Free norcodeine and normorphine concentrations were found to range between 143-50,200 and 205-149,700 microg/l, respectively. A statistically significant relationship was determined between the subject age and the 6-MAM concentration, possibly indicating opiate tolerance in these individuals.  相似文献   
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Will GF 《Newsweek》2002,140(22):92
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This article reviews the major forms of violence against women, including sexual assault, intimate-relationship violence, and stalking and outlines the known psychological effects of such victimization. Also discussed are a number of variables that combine to determine the effects of such victimization, including type and characteristics of the assault; victim variables such as demographics, psychological reactions at the time of the trauma, previous victimization history, current or previous psychological difficulties, and general coping style; and sociocultural factors such as poverty, social inequality, and inadequate social support. The implications of this complexity are explored in terms of psychological assessment and the frequent need for multitarget, multimodal treatment approaches.  相似文献   
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