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51.
We report an interstitial deletion of chromosome 3q26-q28 in a fetus in which anophthalmia had been detected prenatally. FISH analysis, using BAC clones encompassing the SOX2 locus, showed that SOX2 gene was involved in the chromosomal breakpoint of the deletion. This case confirms that haploinsufficiency for SOX2 plays a crucial role in human eye development and emphasizes the necessity of careful chromosomal analysis, including FISH analysis of the 3q region, in case of prenatal discovery of anophthalmia. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
52.
We present a case report on a fetus with multiple malformations, diagnosed by ultrasound at 20 weeks' gestation. From the combination of intrauterine growth retardation and limb abnormalities that were observed, the most likely diagnosis was considered to be Cornelia de Lange Syndrome (CdLS). Following counselling, the mother opted to terminate the pregnancy. Chromosome analysis of cultured amniotic fluid cells showed a karyotype of 46,XX,t(3;5)(q21;p13). Postmortem examination of the baby confirmed the presence of features consistent with a diagnosis of CdLS. This case provides a report of a definitive diagnosis of Cornelia de Lange Syndrome, suspected on the basis of ultrasound imaging and confirmed by amniocentesis findings. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an important cause of hereditary stroke. Mutations in the Notch3 gene are clearly causally linked to this progressive vascular disorder. Cerebral ischemic attacks, cognitive decline, strokes, and vascular dementia constitute the major manifestations of this disorder. This report details the prenatal detection of a Notch3 mutation in the fetus of a couple where the father had a known mutation in this gene. This is the first report of a prenatal diagnosis of CADASIL, and another example of a serious, highly penetrant, and relentlessly progressive degenerative genetic disorder presenting decades after birth and for which prenatal diagnosis is an option. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
54.
从实验室保存的高效好氧反硝化菌种中筛选得到一株抗汞细菌并命名为X1,经生理生化特性和16SrRNA基因序列分析,初步鉴定该菌为恶臭假单胞菌(Pseudomonasputida).对菌株X1进行Hg2适应特性研究,结果表明,对于Hg2浓度为2、67++4、、mg·L-1的实验组,菌体分别需要被延滞12、284018、、h后进入对数期,而8mg·L-1实验组则不能进入对数期;在好氧反硝化过程中,Hg2浓度在7mg·L+-1范围内各实验组的好氧反硝化过程中NO3-N浓度变化速率、NO2-N累积峰值、pH特征点出现时刻随着Hg2浓度的增大而增大(延迟),而Hg2浓度呈现出同硝氮一致的下降趋势,并且在对数期内除汞率能达到100%.研究表明,菌株X1对Hg2最大适宜耐受浓度为7mg·L+-1,相应适应时间约为40h.在最大耐受浓度范围内,菌株X1的生长和好氧反硝化过程呈现出"被抑制-适应-受刺激"的变化规律,其中,被抑制的时间和受刺激的程度都随着Hg2浓度的增大而增大,主要表现为延滞期的延长和对数期的缩短.此外,在对数期,菌株X1的生长速率、达到稳定期的浓度和好+氧反硝化速率也都随着Hg2浓度的增大而增大,且大于无Hg2菌组.++  相似文献   
55.
Survival of children with congenital diaphragmatic hernia (CDH) is mainly dependent on the extent of lung hypoplasia and the presence of additional congenital anomalies or chromosomal aberrations. A chromosomal deletion 15q25-q26.2 in a fetus with prenatally diagnosed CDH and growth retardation is reported. Despite optimal pre- and neonatal management the baby died shortly after birth. There is increasing evidence that the long arm of chromosome 15, and especially the region 15q24 to 15q26, plays a crucial role in the development of the diaphragm. The finding of a deletion within 15q24-26 in a fetus with CDH has to be considered a predictor of poor prognosis. It is of utmost interest for proper parental counselling to search in fetuses with CDH for subtle chromosomal lesions paying special attention to chromosome 15q. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Different loci within the genome of a single species can potentially coevolve in a manner that is analogous to the Red Queen process among species. The major factor driving this antagonistic coevolution among loci is intergenomic conflict, i.e., discord between individuals that is mediated by two or more gene products that are derived from different gene loci. We conclude that antagonistic coevolution is common among loci that code for social interactions, and that it has broad evolutionary implications, especially in the context of speciation and sex chromosome evolution. Received: 15 January 1997 / Accepted after revision: 14 April 1997  相似文献   
60.
In order to provide a noninvasive prenatal diagnosis of the hemoglobin E (Hb E) related disorder, we have evaluated the possibility of identifying the fetal βE-globin gene in maternal plasma. The analysis was performed during 8 to 18 weeks of gestation using DNA extracted from 200 µL of plasma from pregnant women whose husbands carried Hb E. The βE-globin mutation in maternal plasma was detected by a nested PCR amplification followed by the Mnl I restriction analysis. The result was compared with that of routine analysis of the CVS specimens. Among the five pregnant women examined, the fetal βE-globin gene was identified in maternal plasma in three of them and the result was completely concordant with the conventional CVS analysis. This simple noninvasive prenatal detection of the fetal βE-globin gene should prove useful in a prevention and control program of Hb E/β-thalassemia in countries where the βE-globin gene is prevalent. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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