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Non-mosaic trisomy 22 is a common cause of first trimester miscarriage and has a livebirth incidence of 1 in 30 000–50 000. Consequently there is a paucity of information for counselling parents. Detection in the second trimester is rare. It is commonly associated with severe growth retardation and multiple structural abnormalities. Oligohydramnios is frequently seen and can make detection of other abnormalities difficult. The outlook is uniformly poor and survival beyond the first trimester may present management dilemmas. A thorough fetal assessment including high-resolution cytogenetics with or without FISH is required for counselling. Careful plans for intrapartum and neonatal management may be necessary. The recurrence risk is thought to be low but information is very limited as there have been no reported cases of recurrence. We present two case of non-mosaic trisomy 22 including the first to be diagnosed subsequent to investigation for a high serum screening Down's risk. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Andrew B. Sparks Eric T. Wang Craig A. Struble Wade Barrett Renee Stokowski Celeste McBride Jacob Zahn Kevin Lee Naiping Shen Jigna Doshi Michel Sun Jill Garrison Jay Sandler Desiree Hollemon Patrick Pattee Aoy Tomita-Mitchell Michael Mitchell John Stuelpnagel Ken Song Arnold Oliphant 《黑龙江环境通报》2012,32(1):3-9
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Dispersal propensity, reflecting one of the most decisive mammalian life history traits, has been suggested to vary heritably
and to locally adapt to prevailing dispersal conditions in wild house mouse populations. Because individual dispersal propensity
highly significantly covaries with the developmental timing of the onset of agonistic interactions between littermate brothers,
we used agonistic onset as an endophenotype to explore the potential genetic basis of dispersal-related behavioral variation
in male house mice. We found significant covariation of microsatellite marker compositions with the probability of fraternal
pairs to exhibit agonistic relationships before the age of 2 months. In particular, the presence of two alleles associated
with a serotonin transporter protein gene (Slc6a4) and a testosterone dehydrogenase gene (Cyp3a11), respectively, strongly
covaried with the probability of early agonistic onset. These results are congruent with recent findings of microsatellite
length polymorphisms marking regulatory variation of gene expression that is relevant for social behavior, including dispersal
propensity development, in other mammals. Genetic variability for ontogenetic timing of agonistic onset would be in agreement
with genotypic differentiation of the dispersive behavioral syndrome in natural populations that could lead to local adaptation. 相似文献
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Kypros H. Nicolaides 《黑龙江环境通报》2011,31(1):7-15
Effective screening for major aneuploidies can be provided in the first trimester of pregnancy. Screening by a combination of fetal nuchal translucency and maternal serum free-β-human chorionic gonadotrophin and pregnancy-associated plasma protein-A can identify about 90% of fetuses with trisomy 21 and other major aneuploidies for a false-positive rate of 5%. Improvement in the performance of first-trimester screening can be achieved by firstly, inclusion in the ultrasound examination assessment of the nasal bone and flow in the ductus venosus, hepatic artery and across the tricuspid valve, and secondly, carrying out the biochemical test at 9 to 10 weeks and the ultrasound scan at 12 weeks. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献