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51.
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Objectives

To evaluate the clinical significance of nuchal translucency (NT) between the 95th–99th percentile in terms of typical and atypical chromosomal abnormalities (ACAs), associated fetal congenital defects and postnatal outcome.

Methods

A retrospective cohort study of fetuses with NT between the 95th–99th percentile. Data regarding the rate of associated fetal defects, genetic abnormalities and postnatal outcome were collected.

Results

A total of 306 cases of fetuses with an NT between the 95th–99th percentiles were included. The overall rate of genetic abnormalities was 12.1% (37/306). Chromosomal abnormalities were found in 10.1% (31/306) of cases and 2% were ACA (6/306). Within this group, two were pathogenic Copy Number Variants (CNVs) and four were single gene disorders. The overall rate of fetal congenital defects was 13.7% (42/306). All ACAs were found in fetuses with congenital defects. Postnatally, a new diagnosis of a single gene disorder was made in 0.85% of cases (2/236).

Conclusions

The presence of an NT between the 95th–99th percentiles carries a 10-fold increased risk of fetal defects, representing an indication for referral for a detailed fetal anatomy evaluation. The risk of ACA is mainly related to the presence of fetal defects, irrespective of the combined test risk.  相似文献   
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In this paper we argue that there is a duty to inform consumers about the environmental impact of foods, and discuss what this duty entails and to whom it falls. We analyze previous proposals that justify ethical traceability with arguments from sustainability and the respect for the autonomy of consumers, showing that they cannot ground a duty to inform. We argue instead that the duty rests on the right of consumers not to be harmed, insofar as consumers have an interest in the morality of their own agency that is frustrated if they are not informed about the environmental impact of the production and transport of what they consume. Our argument detaches the regulation of labeling from substantive theories of environmental ethics or perfectionist conceptions of citizens’ responsibility, thus defending a case for labeling that is compelling also for those who take the role of the state to be limited to the prevention of harm.  相似文献   
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The presence of geranyl octanoate, previously found in pheromone gland extracts of Agriotes lineatus females, was also demonstrated in gland extracts of A. proximus females. Similar to A. lineatus, geranyl butanoate was present only in trace amounts in A. proximus female gland extracts. In air entrainment samples of female A. lineatus and A. proximus beetles, the relative ratio of geranyl butanoate and geranyl octanoate was higher than that in gland extracts. In addition, comparison of a segment of the mitochondrial cytochrome c oxidase subunit I gene of feral specimens of A. lineatus and A. proximus showed >99% similarity. Both pheromone profile and nucleotide sequence analysis delineate close relationship between the investigated taxa and postulate taxonomic revision. Further studies on sympatric populations of A. lineatus and A. proximus are underway to investigate and better understand possible processes of species diversification.  相似文献   
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Nanoparticles (NPs) contained in commercial products are released and enter into the aquatic ecosystem, posing serious possible risks to the environment and affecting the food chain. Therefore, investigating the potential toxicity of NPs on aquatic organisms has become an important issue. This study assessed the toxicity and trophic transfer of metal oxide NPs from marine microalgae (Cricosphaera elongata) to the larvae of the sea urchin Paracentrotus lividus. Larvae (24 h old) were fed on 2000 cell mL?1 48 h of microalgae contaminated with 5 mg L?1 of several metal oxide NPs (SiO2, SnO2, CeO2, Fe3O4) for 15 days. Larval viability and development were monitored from the 4-arm stage to the 8-arm pluteus stage. A significant decrease in survival was observed in larvae fed with microalgae exposed to SiO2 and CeO2 NPs. Abnormal development, characterised by skeletal degeneration and altered rudiment growth, was observed in all larvae fed with contaminated NP algae. Our findings revealed that SiO2 and CeO2 NPs exerted a toxic effect in the trophic interaction analysed, by reducing sea urchin larval viability, and all metal oxide NPs induced toxicological effects. In conclusion, metal oxide NPs may enter the food chain and become bioavailable for marine organisms, affecting their development.  相似文献   
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Environmental Geochemistry and Health - Civilian and military shooting range facilities cause environmental issues in several countries due to the accumulation of Potentially Toxic Elements; as a...  相似文献   
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Landfilling is a fundamental step in any waste management strategy, but it can constitute a hazard for the environment for a long time. The need to protect the environment from potential landfill emissions makes risk assessment a decision tool of extreme necessity. The heterogeneity of wastes and the complexity of physical, chemical and biological processes that occur in the body of a landfill need specific procedures in order to evaluate the groundwater risk for the environment. Given the complexity of the composition of landfill leachates, the exact contribution of each potential toxic substance cannot be known precisely. Some reference contaminants that constitute the hazard (toxicity) of leachate have to be found to perform the risk assessment. A preliminary ecotoxicological investigation with luminescent bacteria has been carried out on different leachates from traditional and sustainable landfills in order to rank the chemicals that better characterize the leachate (heavy metals, ammonia and dissolved organic content). The attention has been focused on ammonia because it is present in high concentration and can last for centuries and can seriously contaminate the groundwater. The results showed that the toxicity of the leachate might reliably depend on the ammonia concentration and that the leachate toxicity is considerably lower in sustainable landfills where the ammonia had been degraded. This has an important consequence because if the containment system fails (as usually occur within 30-50yr), the risk of groundwater contamination will be calculated easier only in terms of the probability that the ammonia concentration is higher than a reference concentration.  相似文献   
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Hybrid composite made of glauconite and polyaniline was prepared in aqueous solution of citric acid. Scanning electron microscopy combined with energy dispersive X-ray analysis shows uniform aggregates made of glauconite microparticles and polyaniline matrix. The results of X-ray powder diffraction suggest that: (1) citric acid used for the polymerisation of aniline causes formation of emeraldine salt where macromolecular ordering in the amorphous polymer takes place; (2) no chemical interaction between glauconite and emeraldine takes place in the prepared composite. FT-IR spectra of the prepared polymer and composite show features indicating all the functional groups that are present in the diiminoquinone–diaminobenzene state of polyaniline. Thermal stability of the composite was higher than the prepared polymer suggesting the occurrence of an interphase interaction between glauconite and emeraldine. After pyrolysis in purified nitrogen the composite still remained glauconite, and ε-Fe3N together with amorphous and graphitic carbon were found as reaction products. The values of electrical conductivity and magnetization of the composite suggest that optimization of these values might be achieved based upon the relationship between glauconite and polyaniline.  相似文献   
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