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601.
D. H. Spathas A. Divane G. M. Maniatis M. E. Ferguson-Smith M. A. Ferguson-Smith 《黑龙江环境通报》1994,14(11):1049-1054
A prospective study was undertaken to evaluate the use of fluorescence in situ hybridization (FISH) for the detection of trisomy 21 in interphase nuclei of uncultured amniotic fluid cells. Five hundred cases were analysed in situ and classified as normal or abnormal; the results were subsequently checked against the cytogenetic findings. Four hundred and ninety-three were correctly identified as normal with an 86·6 per cent average frequency of scored nuclei exhibiting two signals; six cases were correctly identified as trisomic for chromosome 21 with 81·7 per cent of scored nuclei exhibiting three signals; and one abnormal case involving an unbalanced chromosome 21·21 translocation was falsely scored as normal due to poor hybridization/detection efficiency. The method has been substantially improved and simplified so that it is suitable for the rapid detection of trisomy 21. As aneuploidy detection in interphase does not identify structural chromosome aberrations, it is not a substitute for fetal chromosome analysis. 相似文献
602.
B. N. Chodirker M.D. A. E. Chudley K. M. Macdonald C. R. Harman J. A. Evans 《黑龙江环境通报》1994,14(11):1086-1089
This study was undertaken to evaluate the relationship between maternal serum alpha-fetoprotein (MSAFP) levels and oesophageal atresia (OA). OA occurred in 16 fetuses of mothers who had an MSAFP test in the study interval. The multiple of the median (MOM) value for MSAFP averaged 1·54 ± 0·65 (range 0·5–2·9 MOM), which was significantly higher than the value seen in controls. The median MOM was 1·35. Using a cut-off of 2·5 MOM, the sensitivity of MSAFP for detecting OA was 19 per cent. Although OA should be considered in the differential diagnosis of an elevated MSAFP level, MSAFP cannot be considered an appropriate screening test for OA given the low sensitivity. 相似文献
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Daniel J. Bain Erin M. Copeland Marion T. Divers Marijke Hecht Kristina G. Hopkins Justin Hynicka Michael Koryak Mary Kostalos Lisa Brown Emily M. Elliott Joseph Fedor Michele Gregorich Brady Porter Brenda Smith Christopher Tracey Margaret Zak 《Journal of the American Water Resources Association》2014,50(6):1608-1621
Urban stream restoration continues to be used as an ecological management tool, despite uncertainty about the long‐term sustainability and resilience of restored systems. Evaluations of restoration success often focus on specific instream indicators, with limited attention to the wider basin or parallel hydrologic and geomorphic process. A comprehensive understanding of urban stream restoration progress is particularly important for comparisons with nonurban sites as urban streams can provide substantial secondary benefits to urban residents. Here, we utilize a wide range of indicators to retrospectively examine the restoration of Nine Mile Run, a multi‐million dollar stream restoration project in eastern Pittsburgh (Pennsylvania, USA). Examination of available continuous hydrological data illustrates the high cost of failures to incorporate the data into planning and adaptive management. For example, persistent extreme flows drive geomorphic degradation threatening to reverse hydrologic connections created by the restoration and impact the improved instream biotic communities. In addition, human activities associated with restoration efforts suggest a positive feedback as the stream restoration has focused effort on the basin beyond the reach. Ultimately, urban stream restoration remains a potentially useful management tool, but continued improvements in post‐project assessment should include examination of a wider range of indicators. 相似文献
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Many reports and studies have noted that a significant portion of problem-oriented coastal science does not actually link to decisions. Here, three competitively funded project case studies are studied to determine what funders can and should do to better link science with decisions. The qualitative analysis used for this study indicates that the studied program was seen as being unusually attentive to the issue of linking science to decisions, as opposed to simply generating new knowledge. Nevertheless, much of the data indicate that funders can and should do more. Three ideas figured most prominently in the qualitative data: (1) funders should do more to ensure that the problem itself is defined more thoroughly with people who are envisioned as potential users of the science; (2) funders need to allocate more resources and attention to communicating effectively (with users) throughout the project; and (3) funders need to demand more engagement of users throughout the project. These findings have important implications for how funders review and support science, especially when competitive processes are used. Most importantly, funders should adjust what kind of science they ask for. Secondly, funders need to change who is involved in the review process. Currently, review processes focus on knowledge generation, which means that the reviewers themselves have expertise in that area. Instead, review panels should be balanced between those who focus on knowledge generation and those who focus on linking knowledge to decisions; this is a separate but critical discipline currently left out of the review process. 相似文献