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691.
G. Aubertin S. Cripps G. Coleman B. McGillivray S.L. Yong M. Van Allen D. Shaw L. Arbour 《黑龙江环境通报》2002,22(5):388-394
Cases where initial prenatal diagnosis was made of isolated unilateral multicystic kidney (UMCK) were reviewed to determine appropriate counselling and management strategies. For the 73 cases, chromosome abnormalities, pregnancy complications and family histories were reviewed. In addition, subsequently diagnosed birth defects, and pediatric medical and surgical outcomes were available for 54 cases. Of those with outcome information available renal/genital–urinary tract abnormalities were diagnosed subsequently in 33% and non-renal abnormalities in 16% of cases. Of the non-renal abnormalities, congenital heart defects were most frequent (7%). One chromosome abnormality, a trisomy 21, was present among 32 cases where karyotypes were known (3%). Amniotic fluid volume abnormalities were present in 11 cases but not predictive of associated anomalies, with the exception of one case where polyhydramnios accompanied multiple malformations consistent with VATER association. A family history of structural renal anomalies was reported in 11 cases (20%). There were 14 cases of partial or complete involution (25%), including two cases of complete prenatal involution of the cystic kidneys. No long-term associated morbidity such as hypertension or malignancy was present in our cohort. Based on our study and corroborating literature, amniocentesis should be offered to women when a seemingly isolated UMCK is detected on routine prenatal ultrasound. Furthermore, a detailed ultrasound with careful assessment of the fetal heart and contralateral kidney is indicated at diagnosis and during the third trimester to assess for further evidence of structural abnormalities, as well as amniotic fluid volume abnormalities. Careful assessment of the newborn is indicated with appropriate speciality referral as required. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
692.
Mark W. Schwartz Sharon M. Hermann† and Phillip J. Van Mantgem 《Conservation biology》2000,14(4):1023-1033
Abstract: The Florida torreya ( Torreya taxifolia ) is a coniferous tree endemic to a 35-km stretch of bluffs and ravines along the east side of the Apalachicola River in northern Florida and southern Georgia. This formerly locally abundant tree has declined as a result of disease during the 1950s and is on the U.S. endangered species list. With no seed production in the wild, this species is headed toward extinction. We conducted a survey on roughly 200 trees from 1988 to 1996 and used these data to estimate the likelihood of population persistence during the next several decades. We compared a stage-class transition matrix model ( RAMAS) and an individual-based stochastic model ( TORSIM) of growth and mortality to project future populations. Given the current lack of seed production in the wild, all models predict extinction. The question of concern is the imminence of this predicted extinction. Differing predicted times to extinction would suggest different immediate management recommendations. Both models predicted an over 90% likelihood of persistence during the next 50 years. Predictions differed in that the transition matrix model was less optimistic than the individual-based model regarding persistence. Model sensitivity analysis showed that the results were robust to significant decreases in growth and sprouting probabilities. Submodels identified different persistence likelihoods in different populations. Nonetheless, unless management of the population can facilitate maturation and seed production, extinction of this species in the wild is inevitable. 相似文献
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Nguyen Thi Van Ha A. Prem Ananth C. Visvanathan V. Anbumozhi 《Journal of Cleaner Production》2009,17(14):1272-1280
Eco-industrial networking is considered as a new approach for businesses to improve their competitiveness, economic viability and human and ecosystem health. A cyclic material flow with alternative usage of all materials in the loop is an essential feature of an eco-industrial network. While eco-industrial networking has been primarily applied on the high-tech sector, this paper attempts to apply the principles on the fishery sector of An Giang, a Vietnamese province in the Mekong River Delta. An Giang Province has its own market share in the trade of Tra and Basa fish. The industries in the value chain of Tra and Basa are in a situation that forces them to improve their competitiveness to retain the market share. It was found that forming an eco-industrial network and recruiting new businesses to utilize all materials in the process provides additional revenue apart from reducing waste disposal concerns. This paper details the current market situation, the issues faced and material flow patterns and presents a feasible eco-industrial network. The results of the study indicate that the eco-industrial network creates positive impacts in terms of increased competitiveness, improved socio-economic conditions and cleaner environment. 相似文献
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Network-bound systems such as water and energy systems are increasingly confronted with environmental problems that cannot be solved without changing their modes of provision. More than any other flow provided through a network-bound system, the waste water flow comes very close to intimate personal and social life, complicating the introduction of environmental innovations in this sector. Using the concepts of trust and identity, questions concerning changing consumer roles in two cases of Decentralised Sanitation and Reuse Systems in the Netherlands are addressed. In both cases the building of trust within provider networks and between consumers and providers, as well as the possibility for consumers and providers to identify themselves with the aims of the project were key factors determining the success or failure of environmental innovations in waste water flows. 相似文献
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