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141.
We report the prenatal diagnosis of Wolf-Hirschhorn syndrome (4p –) in a 24-week-old fetus. Echographic features included cystic hygroma, a complex heart defect with right ventricular hypoplasia, and a large placental chorioangioma. We suggest that chorioangioma may be associated with chromosomal imbalance and that systematic careful morphologic examination of the fetus and karyotyping of any pregnancy in which large chorioangioma is detected is advisable. Jugular lymphatic obstruction sequence has not been reported so far in association with 4p– syndrome. 相似文献
142.
L. Shivashankar E. Whitney G. Colmorgen T. Young G. Munshi D. Wilmoth K. Byrne G. Reeves Dr. D. S. Borgaonkar S. R. Picciano P. A. Marttn-Deleon 《黑龙江环境通报》1988,8(2):85-91
A case of tetrasomy i(12p) detected prenatally is reported. The patient, a black, 33-year-old G3P2002 at 24 weeks' gestation with an unremarkable family history presented herself for prenatal care. Ultrasound examination showed a fetus with diminished femoral and humeral lengths, and hydramnios. A level II scan confirmed the presence of an omphalocele. Amniocentesis at 31 weeks showed 47,XY, + i(12p) karyotype. An infant with multiple congenital anomalies was delivered at 34 weeks. The infant died after 5 h. Genetic and ultrasonographic examinations in the third trimester were helpful in the investigation of this fetus with multiple congenital anomalies. The careful, complete team counselling afforded by this approach enabled the mother and family to be well adjusted to the strong possibility (and subsequent reality) of an abnormal infant. 相似文献
143.
Veska Toncheva An Van Den Bulcke Etienne Schacht Joris Mergaert Jean Swings 《Journal of Polymers and the Environment》1996,4(2):71-83
Poly (-caprolactone) (PCL), poly (-valerolactone) (PVL), poly (-caprolactone-co--valerolactone) [P(CL-co-VL)], and poly (-caprolactone-co-ethylene oxide-co--caprolactone) (PCL-PEO-PCL) were synthesized by ring-opening and diol-initiated polymerization of -caprolactone and -valerolactone. The degradation of the samples by chemical hydrolysis and in a soil burial test was evaluated. It was found that PCL, PVL, and P(CL-co-VL) degrade mainly enzymatically. The rate of degradation depends on their molecular weight, chemical structure, composition, and morphology. PCL-PEO-PCL block copolymers exhibit a repelling effect to the microorganisms in the soil, which depends on the molecular weight and relative amount of PEO block in the copolymer. 相似文献
144.
Amniotic fluid cultures from two patients showed trisomy-20 mosaicism. No trisomy-20 cells were found in a normal full term infant and in multiple tissue biopsies and fetal blood from a fetus after a termination of pregnancy. No definitive advice is yet possible for parents where trisomy-20 amniotic cell mosaicism is detected. Fetoscopy and fetal blood sampling are of no value and termination of pregnancy is not indicated by empirical evidence. Preferential trophoblastic non-disjunction (Kalousek and Dill, 1983) is discussed as a possible partial explanation for the variable occurrence and distribution of this type of mosaicism. 相似文献
145.
A total of 66 cases with prenatal diagnosis of trisomy 20 mosaicism was reviewed. Since the majority of cases (85 per cent) was associated with grossly normal phenotype and the abnormalities noted in 15 per cent of cases were inconsistent and rather non-specific, no causal relationship between trisomy 20 mosaicism and a specific malformation syndrome can be established. The possiblity of an association between an abnormal phenotype and a high percentage of trisomy 20 cells (> 60 per cent) must be considered preliminary and be viewed with caution. The fact that cells with trisomy 20 have not been recovered from blood cultures and were detected more frequently from specific fetal tissues, (such as kidney, rectum, oesophagus), and from placental tissues, suggests that trisomy 20 is more likely to be confined to certain fetal organs and to extra-embryonic tissues. This review calls for the collection of more data on all cases of trisomy 20 mosaicism diagnosed prenatally, in order to provide more accurate information to the prospective parents. 相似文献
146.
A family is described in which two anencephalic fetuses were identified in two pregnancies. Autopsy revealed kidney anomalies in both fetuses. Chromosome analysis was performed only on the second fetus, which had a 46,XY,lOq+ karyotype. Parental chromosome analysis showed the maternal karyotype to be 46,XX,t(2;10) (p24;q26) thus demonstrating that the fetus was carrying a duplication 2(p24→pter). Recurrence risks for anencephaly based on the cytogenetic abnormality were much higher than those which would be quoted for isolated anencephaly. This points out the necessity for complete diagnostic studies when a fetus with a neural tube defect is identified. The literature in regard to the 2p duplication phenotype is reviewed. It is possible that the duplication of the distal segment of 2p results in a neural tube defect/kidney anomaly phenotype. 相似文献
147.
Effects of p,p'-DDE exposure on gonadal development and gene expression in Japanese medaka (Oryzias latipes) 总被引:1,自引:0,他引:1
Although 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE),the major and most persistent metabolite of dichlorodiphenyl-trichloroethane (DDT),was continually detected in wild fishes that showed abnormal gonad development such as intersex,little is known about the impact of p,p'-DDE exposure on gonad development in fishes.To survey the effects of p,p'-DDE on gonadal development and gene expressions,male juvenile (20-d post hatch) Japanese medaka (Oryzias latipes) was exposed to 1,5,20,and 100 μg/L p,p'-DDE for two months.Increased hepatosomatic index (HSI) and decreased gonadosomatic index (GSI) were found in the p,p'-DDE-treated groups.Intersex was found in 100 μg/L p,p'-DDE exposure group,as well as 100 ng/L 17α-ethynylestradiol (EE2)group.By quantitative real-time RT-PCR,it was found that gene expressions of vitellogenins (VTG-1,VTG-2),choriogenins (CHG-H,CHG-L),and estrogen receptor α (ER-α) in the liver of the fish were significantly up-regulated by p,p'-DDE exposure.VTC-1 and VTG-2 were recommended as the preferred biomarker for assessing anti-androgenic p,p'-DDE because they were the highest up-regulated among the genes and showed good dose-response relationship.The up-regulated ER-α suggested that a potential synergetic effect would occur when p,p'-DDE coexists with other ER-α-binding endocrine-disrupting chemicals (EDCs). 相似文献
148.
Yuping Chen Hui Yan Yijuan Yao Chunling Zeng Ping Gao Liyue Zhuang Liya Fan Daiqi Ye 《环境科学学报(英文版)》2020,32(8):1-13
Due to the influences of precursors emissions, meteorology, geography and other factors, ozone formation sensitivity (OFS) is generally spatially and temporally heterogeneous. This study characterized detailed spatial and temporal variations of OFS in Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 2012 to 2016 based on OMI satellite data, and analyzed the relationships of OFS with precursors emissions, meteorology and land use types (LUTs). From 2012 to 2016, the OFS tended to be NOx-limited in GBA, with the value of FNR (HCHO/NO2) increasing from 2.04 to 2.22. According to the total annual emission statistics of precursors, NOx emissions decreased by 33.1% and VOCs emissions increased by 35.2% from 2012 to 2016, directly resulting in OFS tending to be NOx-limited. The Grey Relation Analysis results show that total column water (TCW), surface net solar radiation (SSR), air temperature at 2 m (T2) and surface pressure (SP) are the top four meteorological factors with the greatest influences on OFS. There are significant positive correlations between FNR and T2, SSR, TCW, and significant negative correlations between FNR and SP. In GBA, the OFS tends to be NOx-limited regime in wet season (higher T2, SSR, TCW and lower SP) and VOCs-limited regime in dry season (lower T2, SSR, TCW and higher SP). The FNR displays obvious gradient variations on different LUTs, with the highest in “Rural areas”, second in “Suburban areas” and lowest in “Urban areas”. 相似文献
149.
Mats Olsson Thomas Madsen Erik Wapstra Bengt Silverin Beata Ujvari Håkan Wittzell 《Behavioral ecology and sociobiology》2005,58(3):289-294
Good genes are genetic elements that contribute to lifetime reproductive success, regardless of an individuals additional genotype. Their existence is debated, and most work has targeted their viability benefits to the offspring of choosy females. In the present study, we analyze a case of potential good genes effects in adult male sand lizards (Lacerta agilis). We show that males with a particular RFLP (Restriction Fragment Length Polymorphism) MHC genotype (O-males), as opposed to those that lack this genetic element (NO-males), have less ectoparasites under increasing physiological stress (indexed by baseline corticosterone level), and are not constrained by parasites at production of status coloration. Furthermore, O-males are more successful at mate acquisition and guard their partners longer. Ultimately, they have a higher genetic reproductive success as assigned by microsatellites.Communicated by W. Cooper 相似文献
150.
Degradation of the herbicide imazapyr by Fenton reactions 总被引:4,自引:0,他引:4
Ghizlaine?Kaichouh Nihal?Oturan Mehmet?A.?OturanEmail author Kacem?El?Kacemi Abderrahim?El?Hourch 《Environmental Chemistry Letters》2004,2(1):31-33
The degradation of the herbicide imazapyr has been carried out by three advanced oxidation processes involving iron ions as catalysts: Fentons reagent, photo-Fenton and electro-Fenton. We show that all processes are rapid and efficient. The kinetic rate constant was found to be
k=5.4×109 M–1
s–1. The mineralization of imazapyr is almost complete using the photo-Fenton and electro-Fenton processes. 相似文献