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L McNally R C Shaler M Baird I Balazs L Kobilinsky P De Forest 《Journal of forensic sciences》1989,34(5):1070-1077
This study was designed to analyze the effects of the environment and substrata on the quality of deoxyribonucleic acid (DNA) isolated from evidentiary specimens. The quality of DNA isolated from actual casework specimens was determined by measuring its size by agarose gel electrophoresis. The information obtained could be used to predict the suitability of the DNA in the samples for restriction fragment length polymorphism (RFLP) analysis. The evidentiary specimens chosen for DNA were classified according to substrate (scrapings, plastic bags, synthetics, denim, and carpet) and according to a subjective evaluation of the condition of the stain (soiled, damp, or putrefied) and to its size (small or large). The results show that DNA of sufficient quality and high molecular weight (HMW) can be reliably isolated from bloodstains deposited on evidentiary items which have an unknown environmental history and which have dried onto a variety of substrata. Subsequent RFLP analysis of a selected number of these samples verified that the DNA was suitable for this type of analysis. 相似文献
916.
Since its inception in 1914, the Cooperative Extension Service has been delivering technology effectively to the agricultural
community. The history of CES is discussed briefly, and the program's success, in terms of visibility, usage, and economic
impact, is documented. Although the extension model has not been applied widely in industries outside of agriculture, some
states have experimented with technology-transfer programs fashioned after CES. It is argued that these programs have not
acquired the critical mass of resources needed to make them truly effective, and, unless they gain additional support, they
should expand their services to increase their value and assess fees for assistance rendered.
Gregory D. McFall was, during preparation of this paper, an undergraduate research fellow, majoring in physics, mathematics,
and philosophy at Virginia Polytechnic Institute and State University. He currently is doing graduate work at VPI & SU. 相似文献
917.
V P Poluianov 《Sudebno-meditsinskaia ekspertiza》1990,33(3):36-37
Method of chrome detection in the course of forensic chemical investigation in the cadaveric material on the basis of cyclohexan-carbonic acid use is presented. Results of experimental researches showed efficacy of method tested as compared to the common one. Method suggested can be used in laboratory conditions to extract chrome from visceral organs of human cadaver. 相似文献
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T. G. P. Rogers 《The Political quarterly》1956,27(3):260-269
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