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71.
Occipital encephalocele belongs to the family of neural tube defects, which occur in one among 2000 to 5000 live births. Syndromic encephaloceles include Meckel–Gruber syndrome and various chromosomal abnormalities. We report on a fetal case (13 WG) with bilateral cleft lip and palate, choanal atresia, occipital encephalocele, bilateral club feet, bilateral multicystic kidneys, enlarged bladder and urethral atresia. The fetal chromosome analysis showed a maternally inherited unbalanced translocation between the short arm of chromosome 1 and the long arm of chromosome 14, resulting in 1p35-pter deletion and 14q32-qter duplication (46,XY,der(1),t(1;14)(p35;q32)). Since the chromosomal breakpoints have not previously been implicated in syndromic encephalocele, this observation is of interest for the identification of other genes responsible for occipital encephalocele. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
72.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.  相似文献   
73.
We report on a fetus presenting with increased nuchal translucency at 11 weeks' gestation, suggesting cystic hygroma. Chorion villous sampling was performed, and cytogenetic analysis revealed a supernumerary isochromosome 5p leading to tetrasomy 5p: 47,XX,+ i(5p)[7]/46,XX[5] after short-term culture and 47,XX,+ i(5p)[20] after long-term culture. Subsequent targeted sonographic follow-up at 12 and 14 weeks revealed further increase of the NT to 6.4 mm and the additional presence of a congenital heart defect (pulmonary atresia with intact ventricular septum). Termination of pregnancy was performed, and the heart defect was confirmed. Isochromosome 5p was found in varying proportions in all examined organs. Only a few cases of mosaic tetrasomy 5p have been reported in the literature, and recent reports on prenatally detected isochromosome 5p showed a possible relationship to increased nuchal translucency in some cases and also a possible role of confined mosaicism in others. Whereas cases with confined mosaicism did not show suspicious signs on ultrasound, true mosaicism conversely showed increased nuchal thickness as well as structural abnormalities. This is the first report on the association of a cardiac defect with this chromosome aberration. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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75.
Cr(Ⅵ)染毒对小鼠肝脏细胞凋亡以及凋亡相关蛋白的影响   总被引:1,自引:0,他引:1  
为研究六价铬(Cr(Ⅵ))对生物体的细胞凋亡以及凋亡相关蛋白的改变,用0、25、50和100 mg·kg-1的重铬酸钾(K2Cr2O7)对小鼠进行1d或持续5 d灌胃,检测肝脏细胞凋亡以及p53、Bcl-2、Bax蛋白表达水平和caspase-3酶的激活.实验结果显示,Cr(Ⅵ)染毒1 d或5 d后,小鼠肝细胞凋亡率随染毒剂量的增加而增加,并呈明显的剂量-反应关系;p53、Bax蛋白表达升高,Bcl-2蛋白表达下降,easpase-3酶激活增加,且p53、Bcl-2蛋白表达水平和caspase-3酶激活水平在100mg·kg-1剂量组的2个染毒时间段与对照组相比均具有显著性差异,Bax蛋白表达水平仅在100 mg·kg-1染毒5 d的实验组与对照组相比具有显著性差异.结果表明,Cr(Ⅵ)能诱导小鼠肝脏细胞凋亡,p53、Bcl-2、Bax和caspase-3在这个过程中可能起重要作用.  相似文献   
76.
五氯酚对稀有鮈鲫卵黄蛋白原及p53的诱导效应   总被引:1,自引:1,他引:0  
采用中国特有鱼种稀有鮈鲫为实验动物,研究五氯酚(PCP)对其肝脏卵黄蛋白原(VTG)、VTG基因及抑癌基因p53的诱导效应,评价PCP的内分泌干扰作用,并从蛋白和基因表达水平上筛选PCP检测的敏感生物标志物.1.5、15、40、80、120、150、160μg.L-1PCP暴露稀有鮈鲫,同时设置空白、溶剂对照和17α-雌二醇(EE2)阳性对照,运用SDS-PAGE,ELISA法检测经PCP暴露后稀有鮈鲫肝脏VTG蛋白的表达差异;克隆稀有鮈鲫新的VTG和p53基因序列片段,运用实时荧光定量PCR方法检测PCP暴露对基因表达的影响.结果表明,40、80、120、160μg.L-1PCP均能诱导雌雄稀有鮈鲫肝脏VTG蛋白的表达,具有显著的浓度-效应关系;1.5、15、150μg.L-1PCP暴露后,雄性稀有鮈鲫肝脏VTG和p53基因表达均明显升高,具有显著的浓度-效应和时间-效应关系.证明PCP具有雌激素效应,稀有鮈鲫肝脏的VTG蛋白、VTG及p53基因可作为PCP检测的敏感分子生物标志物.  相似文献   
77.
UV/H2O2降解水中硝基酚及影响因素   总被引:11,自引:1,他引:11  
UV H2 O2 氧化对硝基酚实验表明 ,H2 O2 光解产生·OH自由基是对硝基酚降解的直接原因 ,12min内 2 5mg L的对硝基酚去除率达到98%以上。溶液中TOC变化与对硝基酚的去除并不同步 ,说明对硝基酚的降解中生成了一系列的中间产物 ,然后再达到完全矿化的。体系中H2 O2 浓度变化显示产生的中间产物对H2 O2 光解没有明显影响。研究中还对对硝基酚起始质量浓度、H2 O2 浓度及pH影响进行了考察。研究认为UV H2 O2 是对硝基酚脱毒的一种有效方法  相似文献   
78.
五氯酚对稀有鮈鲫胚胎毒性效应研究   总被引:2,自引:0,他引:2       下载免费PDF全文
研究五氯酚(PCP)对稀有鮈鲫(Gobiocypris rarus)胚胎的致畸和毒性效应.以7.5,30,60,120,250μg/L5个浓度的PCP对0hpf(hpf,受精卵孵出时间)的稀有鮈鲫胚胎进行暴露染毒,同时设置空白对照组、二甲基亚砜溶剂对照组和雌二醇(EE2,2.5ng/L)阳性对照组.在立体显微镜下观察整个胚胎的发育过程,统计胚胎的孵化率、96hpf相对存活率和各时期的畸形率,并利用半定量RT-PCR检测胚胎中CYP1A基因和p53基因mRNA的表达.结果表明,PCP暴露能延迟稀有鮈鲫胚胎发育,并造成胚胎卵凝结、心包囊肿、脊柱弯曲等多种畸形甚至死亡.随着PCP暴露浓度的升高,稀有鮈鲫胚胎的孵化率和96hpf相对存活率降低,各时期的畸形率增加,并呈现一定的浓度效应.稀有鮈鲫胚胎CYP1A基因和p53基因mRNA表达被显著诱导,并随PCP浓度的升高而增加.PCP对稀有鮈鲫胚胎发育表现为显著的毒性效应.稀有鮈鲫胚胎孵化率、96hpf相对存活率、各时期畸形率及CYP1A基因和p53基因的诱导表达可以作为评价PCP毒性作用的敏感指标.  相似文献   
79.
From September 2011 to February 2012, ambient air particulate and particulate-bound mercury [Hg(p)] concentrations were measured, together with dry deposition using a cold vapor atomic fluorescence spectrometry (CVAFS) analyser, at two characteristic sampling sites in central Taiwan. Results from the sampling site at Westin Park indicated that the lowest particulate dry deposition and lowest average particulate concentrations in total suspended particles (TSP) occurred in September (29.70±7.47 μ g mp>?2p>×min) and February (34.38±13.60 ng mp>?3p>), respectively. Moreover, results from the Gung-Ming junior high school (airport) site, showed that the highest average particulate dry deposition and average highest particulate concentrations in TSP occurred in February (156.76±30.36 μ g mp>?2p>×min) and January (125.49±9.51 ng mp>?3p>), respectively, during the winter. The Dragon Steel Plant and Han-Shian Aerospace Industrial Development Corporation were both nearby. These factors led to the high Hg(p) concentrations at Taichung Airport (TA) compared with Westin Park. Local large suspended particulates from heavy traffic were the main reason for the high average Hg(p) deposition at Westin Park compared with TA in this study.  相似文献   
80.
Okadaic acid (OA) is a dinoflagellate toxin which accumulates in shellfish producing diarrhetic shellfish poisoning (DSP) in humans. It was found that OA is a highly selective inhibitor of protein phosphatase types 1 (PP1) and 2A (PP2A) which produces a marked increase in phosphorylation of several proteins, including p38 mitogen-activated protein (MAP) kinase. The cytotoxicity attributed to OA and the effects on p38 MAP kinase and calcium current were examined in the oyster Crassostrea gigas in this study. Data showed that p38 MAP kinase is strongly expressed in oyster heart and that OA bioaccumulated in cultured heart cells. Hence the effects of OA was tested in vitro and in vivo on oysters. OA was found to (i) exert a positive chronotropic effect on cultured atrial cardiomyocytes which is related to an increase in calcium current via PKC as shown by patch clamp measurements, (ii) produce an activation/phosphorylation of MAP kinase as shown by Westernblot while the non-phosphorylated p38 remained constant during treatment, (iii) did not induce a pro-apoptotic effect. Data suggest that OA may also stimulate the anti-apoptotic pathway by phosphatase inhibition.  相似文献   
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