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141.
Ellen Hollands Steffensen Anne Skakkebæk Kasper Gadsbøll Olav Bjørn Petersen Thomas Westover Heather Strange The NIPT-SCA-map Study Group Ida Vogel 《黑龙江环境通报》2023,43(2):144-155
Objective
To examine the extent to which sex chromosomes are included in current noninvasive prenatal testing (NIPT) and the reporting practices with respect to fetal chromosomal sex and sex chromosome aberrations (SCAs), in addition to an update on the general implementation of NIPT.Method
A questionnaire addressing the research objectives was distributed by email to fetal medicine and clinical genetics experts in Asia, Australia, Europe and the USA.Results
Guidelines on NIPT are available in the majority of the included countries. Not all existing guidelines address reporting of fetal chromosomal sex and SCAs. In most settings, NIPT frequently includes sex chromosomes (five Australian states, China, Hong Kong, Israel, Singapore, Thailand, USA and 23 of 31 European countries). This occurs most often by default or when parents wish to know fetal sex. In most settings, a potential SCA is reported by stating the risk hereof as “low” or “high” and/or by naming the SCA. Less than 50% of all pregnant women receive NIPT according to respondents from three Australian states, China, Israel, Singapore, Thailand and 24 of 31 European countries. However, this percentage, the genomic coverage of NIPT and its application as primary or secondary screening vary by setting.Conclusion
In most of the studied countries/states, NIPT commonly includes sex chromosomes. The reporting practices concerning fetal chromosomal sex and SCAs are diverse and most commonly not addressed by guidelines. In general, NIPT is variably implemented across countries/states. 相似文献142.
Lima Luíza Siqueira Galiciolli Maria Eduarda Andrade Pereira Meire Ellen Felisbino Karoline Machado-Souza Cleber de Oliveira Cláudia Sirlene Guiloski Izonete Cristina 《Environmental science and pollution research international》2022,29(29):43435-43447
Environmental Science and Pollution Research - As well as a lead-related environmental factor, genetic factors could also corroborate important changes in intelligence quotient (IQ) through... 相似文献
143.
Tianhua Huang Alan Dennis Wendy S. Meschino Shamim Rashid Ellen Mak-Tam Howard Cuckle 《黑龙江环境通报》2015,35(7):709-716
144.
145.
Objective: The purpose of this study was to use the detailed medical injury information in the Crash Injury Research and Engineering Network (CIREN) to evaluate patterns of rib fractures in real-world crash occupants in both belted and unbelted restraint conditions. Fracture patterns binned into rib regional levels were examined to determine normative trends associated with belt use and other possible contributing factors.Methods: Front row adult occupants with Abbreviated Injury Scale (AIS) 3+ rib fractures, in frontal crashes with a deployed frontal airbag, were selected from the CIREN database. The circumferential location of each rib fracture (with respect to the sternum) was documented using a previously published method (Ritchie et al. 2006) and digital computed tomography scans. Fracture patterns for different crash and occupant parameters (restraint use, involved physical component, occupant kinematics, crash principal direction of force, and occupant age) were compared qualitatively and quantitatively.Results: There were 158 belted and 44 unbelted occupants included in this study. For belted occupants, fractures were mainly located near the path of the shoulder belt, with the majority of fractures occurring on the inboard (with respect to the vehicle) side of the thorax. For unbelted occupants, fractures were approximately symmetric and distributed across both sides of the thorax. There were negligible differences in fracture patterns between occupants with frontal (0°) and near side (330° to 350° for drivers; 10° to 30° for passengers) crash principal directions of force but substantial differences between groups when occupant kinematics (and contacts within the vehicle) were considered. Age also affected fracture pattern, with fractures tending to occur more anteriorly in older occupants and more laterally in younger occupants (both belted and unbelted).Conclusions: Results of this study confirmed with real-world data that rib fracture patterns in unbelted occupants were more distributed and symmetric across the thorax compared to belted occupants in crashes with a deployed frontal airbag. Other factors, such as occupant kinematics and occupant age, also produced differing patterns of fractures. Normative data on rib fracture patterns in real-world occupants can contribute to understanding injury mechanisms and the role of different causation factors, which can ultimately help prevent fractures and improve vehicle safety. 相似文献
146.
147.
In a variety of taxa, male reproductive success is positively related to the expression of costly traits such as large body
size, ornaments, armaments, and aggression. These traits are thought to improve male competitive ability and, thus, access
to limited reproductive resources. Females of many species also express competitive traits. However, we know very little about
the consequences of individual variation in competitive traits and the mechanisms that regulate their expression in females.
Consequently, it is currently unclear whether females express competitive traits owing to direct selection or as an indirect
result of selection on males. Here, we examine females of a mildly dimorphic songbird (Junco hyemalis) to determine whether females show positive covariance in traits (morphology and behavior) that may be important in a competition.
We also examine whether trait expression relates either to testosterone (T) in terms of mechanism or to reproductive success
in terms of function. We found that larger females were more aggressive and that greater ability to produce T in response
to a physiological challenge consisting of a standardized injection of gonadotropin-releasing hormone predicted some measures
of female body size and aggression. Finally, we found that aggressive females had greater reproductive success. We conclude
that T may influence female phenotype and that females may benefit from expressing a competitive phenotype. We also suggest
that the mild dimorphism observed in many species may be due in part to direct selection on females rather than simply a correlated
response to selection in males. 相似文献
148.
Schmitt CJ Brumbaugh WG Linder GL Hinck JE 《Environmental geochemistry and health》2006,28(5):445-471
The objective of this study was to evaluate potential human and ecological risks associated with metals in fish and crayfish from mining in the Tri-States Mining District (TSMD). Crayfish (Orconectes spp.) and fish of six frequently consumed species (common carp, Cyprinus carpio; channel catfish, Ictalurus punctatus; flathead catfish, Pylodictis olivaris; largemouth bass, Micropterus salmoides; spotted bass, M. punctulatus; and white crappie, Pomoxis annularis) were collected in 2001--2002 from the Oklahoma waters of the Spring River (SR) and Neosho River (NR), which drain the TSMD. Samples from a mining-contaminated site in eastern Missouri and from reference sites were also analyzed. Individual fish were prepared for human consumption in the manner used locally by Native Americans (headed, eviscerated, and scaled) and analyzed for lead, cadmium, and zinc. Whole crayfish were analyzed as composite samples of 5--60 animals. Metals concentrations were typically higher in samples from sites most heavily affected by mining and lowest in reference samples. Within the TSMD, most metals concentrations were higher at sites on the SR than on the NR and were typically highest in common carp and crayfish than in other taxa. Higher concentrations and greater risk were associated with fish and crayfish from heavily contaminated SR tributaries than the SR or NR mainstems. Based on the results of this and previous studies, the human consumption of carp and crayfish could be restricted based on current criteria for lead, cadmium, and zinc, and the consumption of channel catfish could be restricted due to lead. Metals concentrations were uniformly low in Micropterus spp. and crappie and would not warrant restriction, however. Some risk to carnivorous avian wildlife from lead and zinc in TSMD fish and invertebrates was also indicated, as was risk to the fish themselves. Overall, the wildlife assessment is consistent with previously reported biological effects attributed to metals from the TSMD. The results demonstrate the potential for adverse effects in fish, wildlife, and humans and indicate that further investigation of human health and ecological risks, to include additional exposure pathways and endpoints, is warranted.This study was conducted by the Columbia Environmental Research Center (CERC) of the U.S. Geological Survey (USGS) and cooperating organizations and government agencies. All field and laboratory procedures conformed to the “Guidelines for the use of fishes in research” of the American Fisheries Society (AFS), Institute of Fishery Research Biologists (AIFRB), and American Society of Ichthyologists and Herpetologists (ASIH) Use of Fishes in Research Committee (AFS, AIFRB, and ASIH 2004), and with all USGS and CERC guidelines for the humane treatment of test organisms during culture and experimentation. Use of trade names does not constitute USGS or U.S. government endorsement. 相似文献
149.
Philip N. Owens William H. Blake Ellen L. Petticrew 《Water, Air, & Soil Pollution: Focus》2006,6(5-6):637-645
This paper describes a study examining the potential of mineral magnetic, geochemical and organic properties to determine
if a 2003 wildfire in a catchment in British Columbia, Canada, caused a change in the sources of the suspended sediment transported
in the channel relative to a nearby unburnt (reference) catchment. The results show that some of the properties offer the
potential to determine sediment sources in the unburnt catchment. However, the 2003 wildfire modified the concentrations of
some properties and this can either compromise or enhance their ability as tracers in the burnt catchment. At present, the
source tracing results are inconclusive. This has implications for the use of certain properties as fingerprints and raises
important issues about approaches to sediment source identification. 相似文献
150.
Hwan-Man Park Amar K. Mohanty Lawrence T. Drzal Ellen Lee Deborah F. Mielewski Manjusri Misra 《Journal of Polymers and the Environment》2006,14(1):27-35
Injection molded nanocomposites have been successfully fabricated from cellulose acetate (CA), eco-friendly triethyl citrate
(TEC) plasticizer, and organically modified clay with and without maleic anhydride grafted cellulose acetate butyrate (CAB-g-MA)
as a compatibilizer. The effects of processing conditions such as mixing methods, pre-plasticizing times, extruder retention
times (RT) and addition of compatibilizer on the performance of these nanocomposites have been evaluated. The cellulosic plastic
with CA/TEC (80/20 wt%) was used as the polymer matrix for nanocomposite fabrication. The morphologies of these nanocomposites
were evaluated through X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies. The mechanical properties
of the nanocomposites were measured and have been correlated with the XRD and TEM observations. From all of the sequential
mixing methods used, powder–powder mixing leads to the most transparent nanocomposites. Cellulosic plastic-based nanocomposites
obtained using increased pre-plasticizing times and RT showed better exfoliated structures. In the system containing compatibilizer,
the minimum retention time required for obtaining almost completely exfoliated hybrid nanocomposites was shorter than in the
system without compatibilizer. 相似文献