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51.
The reality of cloning and stem cell research has provoked wonder, fear and anger. These developments have the potential fundamentally to alter humanity. But how well informed is the range of views being expressed? Is progress being threatened by understandable but uninformed fears? Or are scientists rushing toward an ethical abyss, so concerned with what they can do that they never stop to ask what they should do? This article identifies some of the fears and hopes surrounding cloning and stem cell research. It aims to provoke ethical debate in evaluating such research.  相似文献   
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Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method.  相似文献   
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Six ninhydrin analogues containing oxygen, sulfur, and selenium substituents at the C-5 position, 5-(4-nitrophenyl)ninhydrin, and benzo[f]furoninhydrin were evaluated as fingerprint development reagents. The analogues all showed good fingerprint color development but were not superior to ninhydrin in this respect. The benzo[f]furoninhydrin complex was strongly luminescent at room temperature following zinc complexation, while the remaining analogues required cooling to -196 degrees C to produce optimum luminescence. The benzo[f]furo, nitrophenyl, and methyl selenide analogues showed the best potential as fingerprint reagents with the benzo[f]furo analogue comparing favorably with DFO.  相似文献   
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McDowell  Bruce D. 《Publius》1997,27(2):111-127
On 30 September 1996 the U.S. Advisory Commission on IntergovernmentalRelations (ACIR) closed its doors, ending thirty-seven yearsof advocacy for federalism and intergovernmental relations.A majority of members in the Congress felt that A CIR had becomeirrelevant to the issues facing them and agreed that littlewould be lost by terminating the commission. The Clinton administration,although supportive until near the end, withdrew its'supportout of displeasure with the commission's handling of the unfundedfederal mandates issue. The national associations representingstate and local governments were ambivalent. ACIR was no longerlooked to for solutions to the nation's intergovernmental relationsproblems. With the exit of ACIR, the federal government's lastresource for addressing broad intergovernmental issues—beyondthe confines of individual programs—is gone.  相似文献   
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Household survey data on age at first use of alcohol, tobacco, marijuana,and hard drugs can be biased due to sample selection and inaccuraterecall. One potential concern is attrition, whereby individuals who getinvolved with substance use at an early age become increasingly less likelyto be surveyed in successive years. A comparison of data from the NationalHousehold Survey on Drug Abuse (NHSDA) with data from a longitudinal studysuggested that attrition might have caused substantially less bias thandid forward telescoping, the inflating of age at first useover time. The evidence of forward telescoping was particularly pronouncedwith respect to age at first use of alcohol. This paper presents a procedurefor correcting the distribution of age at first use for forward telescoping(but not attrition) by viewing a portion of the NHSDA data collected insuccessive years as constituting a cohort study. Results are presented fromapplying this procedure with NHSDA data collected from 1982 to 1995 forrespondents born 1968–1973. The findings suggest that preventionprograms need to be introduced at an earlier age than would be indicatedby uncorrected retrospective data. Other implications are alsohighlighted.  相似文献   
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