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Bo B. Bet Maartje C. Snoep Elisabeth van Leeuwen Ingeborg H. Linskens Monique C. Haak Lieke Rozendaal Ingmar Knobbe Joost van Schuppen Carlijn E. L. Hoekstra David R. Koolbergen Sally-Ann Clur Eva Pajkrt 《黑龙江环境通报》2023,43(5):629-638
Objectives
To determine the proportion of children that require surgery in the first year of life and thereafter in order to improve the counseling of parents with a fetus with a right aortic arch (RAA).Methods
Fetuses diagnosed with isolated RAA, defined as the absence of intra- or extracardiac anomalies, between 2007 and 2021 were extracted from the prospective registry PRECOR.Results
In total, 110 fetuses were included, 92 with a prenatal diagnosis of RAA and 18 with double aortic arch (DAA). The prevalence of 22q11 deletion syndrome was 5.5%. Six pregnancies were terminated and five cases were false-positive; therefore, the follow-up consisted of 99 neonates. Surgery was performed in 10 infants (10%) in the first year of life. In total, 25 (25%) children had surgery at a mean age of 17 months. Eight of these 25 (32%) had a DAA. Only one child, with a DAA, required surgery in the first week of life due to obstructive stridor.Conclusions
Children with a prenatally diagnosed RAA are at a low risk of acute respiratory postnatal problems. Delivery in a hospital with neonatal intensive care and pediatric cardiothoracic facilities seems only indicated in cases with suspected DAA. Expectant parents should be informed that presently 25% of the children need elective surgery and only incidentally due to acute respiratory distress. 相似文献32.
Michler SP Nicolaus M Ubels R van der Velde M Komdeur J Both C Tinbergen JM 《Behavioral ecology and sociobiology》2011,65(10):1975-1986
An individual’s decision to disperse from the natal habitat can affect its future fitness prospects. Especially in species
with sex-biased dispersal, we expect the cost–benefit balance for dispersal to vary according to the social environment (e.g.,
local sex ratio and density). However, little is known about the social factors affecting dispersal decisions and about the
temporal and spatial patterns of the dispersal process. In our study, we investigated experimentally the effects of the social
environment on post-fledging dispersal of juvenile great tits by simultaneously manipulating the density and sex ratio of
fledglings within forest plots. We expected young females in the post-fledging period mainly to compete for resources related
to food and, as they are subordinate to males, we predicted higher female dispersal from male-biased plots. Juvenile males
compete for vacant territories already in late summer and autumn; thus, we predicted increased male dispersal from high density
and male-biased plots. We found that juvenile females had a higher probability to leave male-biased plots and had dispersed
further from male-biased plots in the later post-fledging phase when juvenile males start to become territorial and more aggressive.
Juvenile males were least likely to leave male-biased plots and had smallest dispersal distances from female-biased plots
early after fledging. The results suggest that the social environment differentially affected the costs and benefits of philopatry
for male and female juveniles. The local sex ratio of individuals is thus an important social trait to be considered for understanding
sex-specific dispersal processes. 相似文献
33.
Joost de Jongh Ang lique Belfroid Theo Sinnige Willem Seinen Martin Van den Berg 《Chemosphere》1992,25(12):1851-1859
The disposition, elimination and cytochrome P450 related enzyme induction of 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PnCDD), 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (HxCDD) and 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) were studied in the liver of the male C57BL/6 mouse. Elimination of all compounds from the liver followed first-order kinetics. Half-lives for PnCDD, HxCDD and PnCDF were 15, 52 and 65 days respectively. 7-Ethoxyresorufin-O-deethylation (EROD) activity in the livers of the treated animals showed a good correlation with the liver tissue concentrations but the slopes of these liver concentration-response curves were not equal for all three compounds. 相似文献
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In population modeling, a considerable level of complexity is often required to provide trustworthy results, comparable with field observations. By assuring sufficient detail at the individual level while preserving the potential to explore the consequences at higher levels, individual-based modeling may thus provide a useful tool to investigate dynamics at different levels of organization. Still, population dynamics resulting from such models are often at odds with observations from the field. This may be partly caused by a lack of focus on the individual dynamics under conditions of food stress and starvation. I developed a physiologically structured, individual-based simulation model to investigate life history of Daphnia and its effect on population dynamics in response to the productivity of the system. In verifying model behavior with available literature data on life history and physiology, I paid special attention to the dynamics of food intake and the verification of individual level results under conditions of food limitation and starvation. I show that the maximum filtering rates under low food levels used in the current model are much closer to measured filtering rates than the ones used in other models. Being consistent with results on physiology and life history from experiments at a wide range of food availability (including starvation), the model generates low amplitude or high amplitude population density cycles depending on the productivity of the system, as observed in field and experimental populations of Daphnia and with the minimum population densities being one to two orders of magnitude lower in the high amplitude than in the low amplitude cycles. To generate results which are not only qualitatively but also quantitatively comparable to experimental and field observations, however, a crowding effect on the filtering response has to be incorporated in the model. 相似文献
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Rail has an important role to play in the development toward a sustainable transportation system. In this perspective, the European Brite Euram Project RAVEL (Rail Vehicle Eco-Efficient Design) has developed a rail sectorwide Design for Environment system to be used and standardized throughout the full supply chain. At the core of the system, quantitative environmental performance indicators for rail vehicles and components are used to incorporate environmental performance target levels in the product requirements and to measure and communicate achieved environmental performance. The concept of eco-efficiency is used to integrate both environmental and economical considerations. The methodology further builds on a standardized material list, standardized data formats, and proactive design guidance. To date, first steps are already taken to integrate the RAVEL project results into sector initiatives toward industrywide acceptance and standardization.Published online
Note: This version was published online in June 2005 with the cover date of August 2004. 相似文献
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