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Mary C. Phelan R. Curtis Rogers Ron C. Michaelis C. Lynn Moore Will Blackburn 《黑龙江环境通报》2001,21(6):457-460
Mosaicism for trisomy 13 and triploidy was detected by amniocentesis performed at 18 weeks' gestation because of fetal anomalies. Pregnancy continued and a live-born male was delivered vaginally at 37 weeks. The infant had features common to both trisomy 13 and triploidy: intrauterine growth retardation (IUGR), small abnormal ears, cleft palate, and a small jaw. In addition, he had complete cutaneous syndactyly of fingers 3 and 4 and partial syndactyly of the toes, as seen in triploidy. Mixoploidy for trisomy 13 and triploidy was confirmed postnatally in blood, skin, and placenta. Examination of chromosome heteromorphisms and DNA markers suggested the presence of two maternal contributions in the triploid cell line. In addition, the extra chromosome 13 in the trisomic cell line was derived from the mother. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Sofia A. Kyriakeas Mary C. Watzin 《Journal of the American Water Resources Association》2006,42(2):425-441
Benthic macroinvertebrate communities in streams adjacent to cornfields, streams where cows had unrestricted access, and reference locations without agriculture were compared to examine the effects of local land use and land use/land cover in the watershed. At each local site, macroinvertebrates and a variety of habitat parameters were measured upstream, adjacent, downstream, and farther downstream of the local land use. A geographic information system (GIS) was used to calculate drainage basin area, land use/land cover percentages in each basin, and the distance from sample sites to the stream source. Three‐way analysis of covariance (ANCOVA) tests with date, site type, and sampling location as main effects were used to explore differences in macroinvertebrate metrics using median substrate size, percent hay/pasture area, and stream depth as covariates. The covariates significantly improved model fit and showed that multiple contributing factors influence community composition. Local impacts were greatest at sites where cows had access, probably because of sedimentation and embeddedness in the substrate. Differences between the upstream and the adjacent and downstream locations were not as great as expected, perhaps because upstream recolonization was reduced by agricultural impacts or because of differences in the intensity or proximity of agriculture to riparian areas in the watershed. The results underscore the importance of both local and watershed factors in controlling stream community composition. 相似文献
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Summary The leaf gland volatile oils of ten sweet gale plants from a Scottish population were extracted in early summer. The results differed notably from reports of other populations in respect of the sesquiterpenes, -elemenone and germacrone, which were major components of the volatile oil. Three dihydrochalcones were also detected in the volatile oil. Variation within the population existed, particularly with respect to the relative importance of germacrone. Five plants were resampled in late summer and exhibited a marked reduction in -elemenone, a lesser reduction in germacrone and changes in the proportions of some monoterpenes. 相似文献
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This paper presents development of a first approximation of a Namibian, national level, land degradation monitoring system.
The process involved a large number of stakeholders and led to the definition of four primary indicators that were regarded
as related to land degradation in Namibia: population pressure, livestock pressure, seasonal rainfall and erosion hazards.
These indicators were calculated annually for the period 1971–1997. Annual land degradation risk maps were produced for the
same period by combining the indicators. A time series analysis of results generated by indicators was undertaken at two sites.
The analysis revealed a general trend towards an increased land degradation risk over the period 1971–1997. A decrease in
annual rainfall and an increase in livestock numbers caused this negative trend at one site, while decreased annual rainfall
and increased human population were the causes at a second site. Evaluation of resulting maps through direct field observations
and long-term monitoring at selected study sites with different conditions relevant for the indicators defined, is an essential
next step. 相似文献
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Sarah Simpson Mary Mahoney Elizabeth Harris Rosemary Aldrich Jenny Stewart-Williams 《Environmental Impact Assessment Review》2005,25(7-8):772
In Australasia (Australia and New Zealand) the use of health impact assessment (HIA) as a tool for improved policy development is comparatively new. The public health workforce do not routinely assess the potential health and equity impacts of proposed policies or programs. The Australasian Collaboration for Health Equity Impact Assessment was funded to develop a strategic framework for equity-focused HIA (EFHIA) with the intent of strengthening the ways in which equity is addressed in each step of HIA. The collaboration developed a draft framework for EFHIA that mirrored, but modified the commonly accepted steps of HIA; tested the draft framework in six different health service delivery settings; analysed the feedback about application of the draft EFHIA framework and modified it accordingly. The strategic framework shows promise in providing a systematic process for identifying potential differential health impacts and assessing the extent to which these are avoidable and unfair. This paper presents the EFHIA framework and discusses some of the issues that arose in the case study sites undertaking equity-focused HIA. 相似文献
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Robert H. Gray 《Environmental monitoring and assessment》1993,26(2-3):263-276
Environmental monitoring has been an ongoing activity on the U.S. Department of Energy's Hanford Site in southeastern Washington for almost 50 years. Objectives are to detect and assess potential impacts of Site operations on air, surface and ground waters, foodstuffs, fish, wildlife, soil and vegetation. Data from monitoring effects are used to calculate the overall radiological dose to humans working onsite or residing in nearby communities. In 1989, measured Hanford Site perimeter concentrations of airborne radionuclides were below applicable guidelines. Concentrations of radionuclides and nonradiological water quality in the Columbia River were in compliance with applicable standards. Foodstuffs irrigated with river water taken downstream of the Site showed radionuclide levels that were similar to those found in foodstuffs from control areas. Low levels of 137Cs and 90Sr in most onsite wildlife samples and concentrations of radionuclides in soils and vegetation from on- and offsite locations were typical of those attributable to worldwide fallout. The calculated dose potentially received by a maximally exposed individual (i.e., based on hypothetical, worst-case assumptions for all routes of exposure) in 1989 (0.05 mrem/yr) was similar to those calculated for 1985 through 1988.In addition to monitoring radioactivity in fish and wildlife, population numbers of key species are determined. Chinook salmon (Oncorhynchus tshawytscha) spawning in the Columbia River at Hanford has increased in recent years with a concomitant increase in winter roosting activity of bald eagles (Haliaeetus leucocephalus). An elk (Cervus elaphus) herd, established by immigration in 1972, is also increasing. The Hanford Site currently serves as a refuge for Canada goose (Branta canadensis), great blue heron (Ardea herodias), and various plants and other animals, e.g., mule deer (Odocoileus hemionus), and coyotes (Canis latrans). 相似文献