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971.
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Isolation of deoxyribonucleic acid (DNA) from saliva and forensic science samples containing saliva. 总被引:4,自引:0,他引:4
D J Walsh A C Corey R W Cotton L Forman G L Herrin C J Word D D Garner 《Journal of forensic sciences》1992,37(2):387-395
Saliva and saliva-stained materials were examined as potential sources of deoxyribonucleic acid (DNA) for DNA analysis and identity testing. In this paper, the authors demonstrate that DNA was isolated and DNA banding patterns suitable for DNA typing were obtained from fresh saliva and various saliva-stained materials, such as envelopes, buccal swabs, gags, and cigarettes. Furthermore, DNA and DNA banding patterns were obtained from actual forensic evidentiary samples containing mixed saliva/semen stains. The DNA banding patterns obtained from saliva or saliva-stained material were indistinguishable from the patterns obtained from blood or hair from the same individual. Intact DNA was readily isolated and DNA banding patterns were obtained from saliva stored at -20 degrees C and dried saliva stains stored under varying conditions. We conclude that saliva and saliva-stained material can be good sources of DNA for analysis and for DNA typing in certain forensic settings. 相似文献
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975.
Conclusions In a review of available literature on the topic of adverse effects of the use of hallucinogenics, the authors found some
remarkable evidence. First, there is not evidence that these drugs are physically or emotionally addictive. In fact, users
generally discontinue use because of the impact of altering states of consciousness. Few have the desire to experience these
effects beyond satisfying their curiosity about the drugs.
There seem to be some specific personality factors that predispose individuals to experiment with psychedelic drugs, and certainly,
specific personality types are prone to be associated with negative side effects in both the short and long-term. In light
of the considerable amount of research which supports the premise that LSD is not as dangerous as once assumed, perhaps restrictive
hiring policies should be reviewed and reevaluated in the case of the one-time user. If an individual passes all testing,
and personal history shows stability, disqualifying a candidate for prior LSD use does not appear to be supportable by research
finding. Again, this report is not meant to diminish the negative effect of hallucinogens on a small portion of our society.
The intent is to point out that the medical literature does not support the contention that one-time hallucinogen use carries
with it any undesirable long-term consequences. The importance of considering an individual within the context of testing
and background can not be minimized. 相似文献
976.
Larvae of the flesh fly Boettcherisca peregrina (Robineau-Desvoidy) were reared on the tissues of rabbits to study the effects of heroin on the development rates of this species. The rabbits were given 6, 12, 18, and 24 mg of heroin by cardiac puncture. From Hours 18 to 96, larvae feeding on tissues containing heroin (as morphine) developed more rapidly than those feeding on tissues from the control. The time required for pupation was significantly greater for colonies fed on tissues from heroin-dosed rabbits than for the control colony. The differences observed in the rates of development were sufficient to alter postmortem interval estimates based on larval development by up to 29 h and estimates based on pupal development by 18 to 38 h. 相似文献
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978.
George W. Grayson Author Vitae 《Orbis》2007,51(2):279-297
Although differences between the Mexican and U.S. political systems have narrowed of late, a huge gulf continues to separate the two systems. At the heart of this disparity lies the phenomenon of corporatism, a social concept that is virtually absent in U.S. political discourse and traditions. This article considers the intellectual origins of corporatism, why it meshes so well with Ibero-Hispanic society, and how Mexico City's former mayor, Andrés Manuel López Obrador, fashioned his own brand of corporatism to confront the administration of Felipe Calderón Hinojosa, who defeated him in the July 2006 presidential race. 相似文献
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980.