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891.
Cytogenetic data from the United States NICHD collaborative study of chorionic villus sampling (CVS) were used to evaluate the clinical significance of chorionic mosaicism. The 10 754 patients with normal cytogenetic results were compared wtih 108 patients (1.0 per cent) with placental mosaicism and 181 patients (1.6 per cent) with pseudomosaicism. Of the pregnancies intended to continue, the pregnancy loss rate was significantly greater in patients with placental mosaicism than in the cytogenetically normal cohort (8.6 vs. 3.4 per cent, p <0.05). However, there was no difference in the frequencies of abruptio placenta, preterm labour or delivery, small-for-gestational-age newborns, pregnancy-induced hypertension, or neonates with Apgar scores less than 7.  相似文献   
892.
By chance, we had the opportunity to make serial sonographic observations of the extrusion of meconium in a case of meconium peritonitis. Inflammation leads to exudative processes and production of fluid (ascites) in the fetal abdomen. Sonography at that stage of the disease may lead to a misdiagnosis such as ‘fetal ascites’ or ‘non-immune hydrops’. After bowel perforation and extrusion of meconium, the latter appears as a solitary mass inside fetal ascites or as disseminated echogenic masses distributed subdiaphragmatically or perihepatically. Within a couple of days, in most cases the echogenicity of the masses increases. Calcifications lead to distinct shadowing. These calcifications are often the only visible signs of a previous meconium peritonitis. Serial sonograms are essential for the management of pregnancies with meconium peritonitis. If the amount of fetal ascites does not increase and no signs of cardiovascular stagnation appear, no invasive intrauterine diagnostic and therapeutic steps are required. In none out of the nine cases was a cause found.  相似文献   
893.
The aim of this paper is to presents a progress report on how a subnational jurisdiction, the Australian state of Victoria, is attempting to implement regional governance for sustainability through its catchment planning framework. The paper examines the lessons learnt from a best practice approach to the implementation of network governance to see whether there are actions that can be taken to improve regional governance for sustainability in Victoria. The authors argue that Victoria is implementing a network governance approach to natural resource management (NRM) as a significant component of sustainability and that this has certain advantages. In particular the emergence of Regional Catchment Strategies developed by the State's ten statutory Catchment Management Authorities as 'regional sustainability blueprints' is bringing a significant level of maturity to the state's governance framework. Furthermore the state is currently working to complete its governance for sustainability through new statewide integrating frameworks—an Environmental Sustainability Framework as well as a statewide Catchment Management and Investment Framework. The paper concludes that taking a network governance approach could have transformative potential but there are significant challenges ahead: the complex task of aligning of national, state, catchment and local government strategies through an outcomes focus; the scarcity of mechanisms and tools to assist in translation of strategies into integrated investment priorities; gaps in knowledge and understanding of natural resource management problems; limitations in the capacity of regional and local bodies, including local government; and getting the policy tools right within the framework. However, as the best practice examples illustrate, taking a gradual approach to the development of the institutions—building on successive wins in capacity—is the best and only way to proceed.  相似文献   
894.
ABSTRACT

Public schools are more than educational institutions; they are essential to creating liveable neighbourhoods. Despite their importance, public schools are being permanently closed across North America, and particularly in the Canadian province of Ontario. In 2015, one of Ontario's public school boards made the decision to permanently close the province's oldest public high school, located in the urban core of the historic midsized city of Kingston. While the school is not scheduled to close until late 2019, the established fate of this prominent public asset has important consequences for the liveability of Kingston's urban core. Accordingly, the objective of this study was to document residents’ perceived impacts of the decision to close to Kingston Collegiate Vocational Institute (KCVI) on liveability in the school's catchment area. We observed widespread dissatisfaction with the decision to close KCVI (85%), with large proportions of respondents (above 40%) anticipating KCVI's closure to negatively impact neighbourhood liveability in various ways in the future. Approximately one-quarter of respondents indicated that they have considered moving as a result of the decision, and among these, concerns about negative impacts to household-level well-being were particularly acute. Given the socio-demographic profile of respondents who have considered moving, these findings suggest that the closure of KCVI could have a destabilising effect on the neighbourhoods within the KCVI catchment area by driving families out of the city's urban core. Our findings suggest that policies to address concerns of under-enrolment are short-sighted and undermine efforts of other sectors to promote liveable communities.  相似文献   
895.
The capacity to sustainably govern complex socio-ecological systems (SES) has been identified as a necessary but daunting task by SES scholars, resource stewards and stakeholders. This research sought to inform the question: What are determinant capacities and functional linkages that can be incorporated into diagnostic tools for analysts seeking to improve sustainable socio-economic system SES governance? Literature was used to identify and translate determinant capacities and functional linkages into a quantifiable metric of governance quality. The tool was developed from ecological, business, governance and decision science literature. This tool recognizes the dynamic and systemic linkages between the resources and the social systems that use and govern them for improving systems thinking and SES outcomes. The tool was tested to determine its ability to capture perceived characteristics of governance quality and problem management using Michigan’s cleanup and redevelopment program. The results of this research indicated that the exploratory tool was reliable and valid. This research contributes to the evolving body of SES frameworks, specifically the study of individual and organizational capacities for improved SES outcomes. The implications of this research suggest participatory network-based governance with higher levels of resource exchange, in the form of interdependency, trust, diplomacy and reciprocity, aligns with practitioners’ perceptions of improved program performance. Further, while some capacities and related findings of this research may be context specific, concepts associated with the development and testing of this diagnostic tool, such as the use of systems thinking, participatory network-based governance, and related competencies, may have more universal application.  相似文献   
896.
897.
Familial congenital pyloric atresia is a rare malformation of the fetal gastrointestinal tract. It usually manifests as maternal polyhydramnios and enlarged fetal stomach on ultrasound scan. Sonographic prenatal diagnosis and management of a pregnancy complicated by familial congenital pyloric atresia are presented.  相似文献   
898.
A fetus with mucopolysaccharidosis type IV A (Morquio type A) is described. The family had one affected child exhibiting symptoms of classical Morquio A disease, and late in the subsequent pregnancy prenatal diagnosis was requested. At 23 weeks' gestation, moderate ascites was detected by detailed ultrasound scan and keratan sulphate was found in the amniotic fluid. The pregnancy was terminated by prostaglandin induction and the diagnosis of mucopolysaccharidosis type IV A was confirmed by demonstration of a deficiency of N-acetylgalactosamine-6-sulphate (GalNac-6-S) sulphatase in cultured amniotic cells and in post-mortem fibroblast cultures. The activities of β-galactosidase and arylsulphatase A were normal, ruling out Morquio disease type B and multiple sulphatase deficiency. These results indicate that mucopolysaccharidosis IV A (a disease that predominantly affects the skeletal system) may produce ascites in the fetus to such an extent that it can be detected by ultrasound.  相似文献   
899.
900.
Spread of manure pathogens is of considerable concern due to use of manure for land application. In this study, the effects of four static pile treatment options for bovine manure on die-off of a generic Escherichia coli, E. coli O157:H7 surrogate, Salmonella Senftenberg, Salm. Typhimurium, and Listeria monocytogenes were evaluated. Bovine manure spiked with these bacteria were placed in cassettes at the top, middle, and bottom sections of four static pile treatments that reflect minimal changes in pile construction with and without straw. Temperatures were monitored continuously during the 28 day self-heating period. E. coli and salmonellae were reduced from 8 to 9 log10 CFU g?1 to undetectable levels (<1.77 log10 MPN g?1) at 25–30 cm depths within 7 days in all pile sections except for the manure-only pile in which 3–4 logs of reduction were obtained. No L. monocytogenes initially present at 6.62 log10 CFU g?1 were recovered from straw-amended piles after 14 days, in contrast with manure-only treatment in which this pathogen was recovered even at 28 days. Decline of target bacterial populations corresponded to exposure to temperatures above 45 °C for more than 3 days and amendments of manure with straw to increase thermophilic zones. Use of straw to increase aeration, self-heating capacity, and heat retention in manure piles provides producers a minimal management option for composting that enhances pathogen die-off and thereby reduces risk of environmental spread when manure is applied to land.  相似文献   
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