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141.

Objective

To evaluate and compare the outcome of fetuses and neonates with congenital small bowel obstructions (SBO), evaluate the screening performance of prenatal ultrasound for SBO and identify possible risk factors for adverse outcomes.

Methods

All cases referred to the Amsterdam University Medical Centers between 2007 and 2021 for a prenatal suspected SBO, supplemented by cases of postnatal diagnosis of SBO, were included. The primary outcome was survival after 24 weeks of gestation until the first year of life.

Results

147 cases of SBO were included with a survival rate of 86.2% (119/138) after 24 weeks of gestation until the first year of age. Additional structural or chromosomal anomalies were found to have an increased risk of adverse outcomes. Intrauterine fetal demise occurred in 10/147 (6.8%) cases and 9/147 (6.1%) cases died during postnatal follow-up. The overall positive predictive value of all prenatally diagnosed cases was 91.5%. Surgical correction was performed in 123/128 (96.0%) of the live-born cases.

Conclusions

Congenital SBO has an overall favorable prognosis, but the outcome is negatively impacted by the possible presence of additional structural or chromosomal anomalies. Fetal monitoring in the early third trimester should be considered, since all cases of Intrauterine fetal demise occurred between 30 and 35 weeks of gestation.  相似文献   
142.
The unrivaled growth in e-commerce of animals and plants presents an unprecedented opportunity to monitor wildlife trade to inform conservation, biosecurity, and law enforcement. Using the internet to quantify the scale of the wildlife trade (volume and frequency) is a relatively recent and rapidly developing approach that lacks an accessible framework for locating relevant websites and collecting data. We produced an accessible guide for internet-based wildlife trade surveillance. We detailed a repeatable method involving a systematic internet search, with search engines, to locate relevant websites and content. For data collection, we highlight web-scraping technology as an efficient way to collect data in an automated fashion at regularly timed intervals. Our guide is applicable to the multitude of trade-based contexts because researchers can tailor search keywords for specific taxa or derived products and locations of interest. We provide information for working with the diversity of websites used in wildlife trade. For example, to locate relevant content on social media (e.g., posts or groups), each social media platform should be examined individually via the site's internal search engine. A key advantage of using the internet to study wildlife trade is the relative ease of access to an increasing amount of trade-related data. However, not all wildlife trade occurs online and it may occur on unobservable sections of the internet.  相似文献   
143.

Background

Polychlorinated biphenyls [PCBs], perfluorinated compounds, and polybrominated diphenyl ethers [PBDEs] were retrospectively analyzed in archived herring gull (Larus argentatus) eggs from the North and the Baltic Sea over the last 20 years. The aim was to assess temporal trends and effects of regulatory measures.

Results

PCBs (sum of 7 congeners) were highest in eggs from the North Sea island Trischen, i.e., 3,710 to 20,760 ng/g lipid weight [lw] compared to 2,530 to 11,650 ng/g lw on the North Sea island Mellum and 4,840 to 9,190 ng/g lw on the Baltic Sea island Heuwiese. During the study period, PCBs decreased significantly. Concentrations of PFOS ranged between 46 and 170 ng/g wet weight [ww] at Trischen, 39 to 99 ng/g ww at Mellum, and 20 to 159 ng/g ww at Heuwiese. Since 2000 and 2003, concentration levels decreased in eggs from Mellum and Heuwiese, respectively. Perfluorooctanoic acid was the dominant perfluorinated carboxylic acid in the North Sea eggs (Trischen 2.0 to 74 ng/g ww; Mellum 2.6 to 118 ng/g ww), whereas perfluoroundecanoate [PFUnA] and perfluorodecanoate [PFDA] (means 3.9 ± 3.6 ng/g and 2.9 ± 2.3 ng/g ww, respectively) dominated in the Baltic Sea eggs. At all three locations, longer-chained perfluorinated carboxylic acids (perfluorononanoate, PFDA, PFUnA, perfluorododecanoate) increased during the monitoring period. PBDE concentrations (sum of 35 congeners) in eggs were in the ranges of 282 to 2,059 ng/g lw (Mellum), 116 to 1,722 ng/g (Trischen), and 232 to 2,021 ng/g lw (Heuwiese). Congeners associated with commercial Penta- and Octa-BDE formulations decreased during the study period. No decrease was observed for technical Deca-BDE.

Conclusion

Effects of regulatory measures were apparent for PCBs and Penta- and Octa-BDE, while no consistent trend is noticeable for PFOS.  相似文献   
144.
A method for the determination of safety properties for micro reactors and micro structured components is presented. Micro structured reactors are not inherently safe but the range of safe operating conditions of micro reactors are extended since the explosion region is reduced. The λ/3 rule was demonstrated to be applicable to micro scale tubes for stoichiometric mixtures of ethane–oxygen and ethane–nitrous oxide. Furthermore first results from an investigation concerning detonation propagation through a micro reactor of non-ideal geometry are shown. Initial pressure investigated is ranging from low pressure up to 100 kPa.  相似文献   
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149.
The tap water samples were collected from the users' ends in several areas of Shanghai, which is located in Taihu Lake basin, Eastern China. Source water samples were also collected from two municipal source water facilities at the same time. Samples were assayed by three different short-term mutagenicity test systems: Salmonella/microsome assay (Ames test), the Arabinose resistance test (Ara test) and the SOS/umu test. The data showed that two source water samples did not display direct mutagenic potentials. Two tap water samples from city north, which were directly from Yangtze River, were also not mutagenic. Water samples from city south and middle which used source water originating from Taihu Lake were proved to be contaminated with mutagenic potentials by three different assay techniques. The boiled water displayed an even stronger mutagenic potential compared to its original tap water. The molecular mechanism of mutagenicity was associated with a reading frame-shifting potential. GC-MS analysis of tap water extracts from city middle and corresponding source water was compared. Qualitatively similar spectra were observed except for the peaks of three chlorinated aromatic hydrocarbon compounds, which existed only in the tap water. Since the water source has been polluted, raw water was heavily chlorinated in order to sterilize. More toxic compounds, including mutagens, might form during the multi-chlorination. Caution about the possibility of elevated cancer risks in the population that consumes heavily chlorinated water should be kept in mind. A cohort study in the residents of Shanghai is required.  相似文献   
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