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681.
Dr. J. F. Bruch P. Metezeau N. Garcia-Fonknechten Y. Richard V. Tricottet B.-L. Hsi A. Kitzis C. Julien E. Papiernik 《黑龙江环境通报》1991,11(10):787-798
Three monoclonal antibodies (MAbs) against trophoblast (GB17, GB21, and GB25) and flow cytometry were used to sort trophoblast-like cells (TLCs) from peripheral blood of pregnant women. Sorted TLCs were processed for electron microscopy and fetal DNA amplification of the Y-specific sequences from mothers carrying male fetuses. At the ultra-structural level, most of the nucleated cells had the morphology of leucocytes, suggesting maternal contaminants, and we did not find the characteristic features of the free inter-villous trophoblast cells. Nevertheless, polymerase chain reaction (PCR) analysis showed an amplification of Y-specific sequences in two out of three samples of sorted TLCs. These results suggest that besides the maternal leucocytes, sufficient trophoblast nucleated fetal cells can be obtained using cell enrichment by sorting. This sensitive method holds promise for non-invasive prenatal diagnosis of fetal sex and if sufficient Y(positive) nuclei are found, for the diagnosis of selected numerical chromosome abnormalities. 相似文献
682.
Introduction
Falls in older Australians are a significant public health issue with one in three older people falling one or more times each year.Method
Many fall prevention randomized controlled trials have been conducted in Australia as well as across the world.Results
The findings of these studies now constitute a substantial evidence base that can provide direction for health and lifestyle interventions for preventing falls in older people. This research evidence has contributed to health policy in Australia to some extent, but is yet to be widely implemented into practice. This opinion piece overviews previous policy initiatives and describes a new Partnership research program funded by the Australian National Health and Medical Research Council (NHMRC), which seeks to further influence health policy and address the ongoing research-practice gap. 相似文献683.
Six cases of macrocystic and one case of microcystic congenital adenomatoid lung malformation were diagnosed by ultrasound between 20 and 31 weeks of gestation. Combined polyhydramnios and fetal hydrops was present in three cases, polyhydramnios alone in one case, and isolated fetal hydrops also in one case. In the remaining two cases, both polyhydramnios and fetal hydrops were absent. Fetal outcome was poor, i.e., two terminations of pregnancy, three early neonatal deaths, and two survivors. 相似文献
684.
Spiders are fascinating model species to study information-acquisition strategies, with the web acting as an extension of the animal’s body. Here, we compare the strategies of two orb-weaving spiders that acquire information through vibrations transmitted and filtered in the web. Whereas Araneus diadematus monitors web vibration directly on the web, Zygiella x-notata uses a signal thread to remotely monitor web vibration from a retreat, which gives added protection. We assess the implications of these two information-acquisition strategies on the quality of vibration information transfer, using laser Doppler vibrometry to measure vibrations of real webs and finite element analysis in computer models of webs. We observed that the signal thread imposed no biologically relevant time penalty for vibration propagation. However, loss of energy (attenuation) was a cost associated with remote monitoring via a signal thread. The findings have implications for the biological use of vibrations by spiders, including the mechanisms to locate and discriminate between vibration sources. We show that orb-weaver spiders are fascinating examples of organisms that modify their physical environment to shape their information-acquisition strategy. 相似文献
685.
J. Sun Y. P. Li X. W. Zhuang S.W. Jin G. H. Huang R. F. Feng 《Mitigation and Adaptation Strategies for Global Change》2018,23(4):553-578
In this study, an integrated simulation-based allocation modeling system (ISAMS) is developed for identifying water resources management strategies in response to climate change. The ISAMS incorporates global climate models (GCMs), a semi-distributed land use-based runoff process (SLURP) model, and a multistage interval-stochastic programming (MISP) approach within a general framework. The ISAMS can not only handle uncertainties expressed as probability distributions and interval values but also reveal climate change impacts on water resources allocation under different projections of GCMs. The ISAMS is then applied to the Kaidu-kongque watershed with cold arid characteristics in the Tarim River Basin (the largest inland watershed basin in China) for demonstrating its efficiency. Results reveal that different climate change models corresponding to various projections (e.g., precipitation and temperature) would lead to changed water resources allocation patterns. Variations in water availability and demand due to uncertainties could result in different water allocation targets and shortages. A variety of decision alternatives about water allocations adaptive to climate change are generated under combinations of different global climate models and ecological water release plans. These findings indicate that understanding the uncertainties in water resources system, building adaptive methods for generating sustainable water allocation patterns, and taking actions for mitigating water shortage problems are key adaptation strategies responding to climate change. 相似文献
686.
Patrick F. Dowd Eric T. Johnson 《Mitigation and Adaptation Strategies for Global Change》2018,23(7):1063-1081
Warming climatic conditions can pose problems for crop production in many parts of the world, but detailed information on the expression of heat and drought stress resistance genes of potentially affected crop plants is lacking. This information is important to have in order to most efficiently guide the breeding of crops that are adapted to new climatic conditions. A maize (Zea mays) gene microarray, a method used worldwide to evaluate the expression of tens of thousands of genes at once, was used to investigate changes in expression of genes involved in resistance to heat and water stress in milk stage popcorn kernels from undamaged and insect-damaged ears. Popcorn is a form of maize that is more susceptible to heat and drought stress due to its smaller root system. In years of heat and drought stress, expression of many heat shock- and senescence-related proteins increased compared to the year when weather was closer to average conditions, but the expression of many genes related to drought stress resistance decreased in years of weather stress. A different complex of heat shock protein and water stress resistance protein genes had higher expression in kernels from undamaged compared to insect-damaged ears in years of heat and drought stress. These results indicate that the interaction of biotic components, such as insects, are important to consider in developing crop lines with adaptation to stress as this will help identify additional genes and their regulatory components involved in heat and drought stress resistance that might otherwise be overlooked, and will likely be an important strategy for the most effective development of climate stress-tolerant crops globally. 相似文献
687.
G. La Rosa Y. T. R. Proroga D. De Medici F. Capuano M. Iaconelli S. Della Libera E. Suffredini 《Food and environmental virology》2018,10(1):127-131
Shellfish samples (n = 384) from production areas, water samples from the same areas (n = 39) and from nearby sewage discharge points (n = 29) were analyzed for hepatitis E virus (HEV) by real-time and nested RT-PCR. Ten shellfish samples (2.6%) and five seawater samples (12.8%) tested positive for HEV; all characterized strains were G3 and showed high degree of sequence identity. An integrated surveillance in seafood and waters is relevant to reduce the risk of shellfish-associated illnesses. 相似文献
688.
689.
J. Besseau-Ayasse C. Violle-Poirsier A. Bazin N. Gruchy A. Moncla F. Girard M. Till F. Mugneret A. Coussement F. Pelluard M. Jimenez P. Vago M. F. Portnoï C. Dupont C. Beneteau F. Amblard M. Valduga J. L. Bresson F. Carré-Pigeon N. Le Meur S. Tapia C. Yardin A. Receveur J. Lespinasse E. Pipiras M. P. Beaujard P. Teboul S. Brisset M. Catty E. Nowak N. Douet Guilbert H. Lallaoui S. Bouquillon V. Gatinois G. Joly-Helas F. Prieur F. Cartault D. Martin P. Kleinfinger D. Molina Gomes M. Doco-Fenzy F. Vialard 《黑龙江环境通报》2014,34(5):424-430