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991.
目的:探讨三维超声成像技术在产前胎儿畸形筛查中的应用价值.方法:应用二维及三维超声检查98例合并畸形的胎儿,比较两者对胎儿畸形的诊断符合率,并评估两者提供的诊断信息有无差别.结果:98例胎儿中,经引产和随访共发现胎儿结构异常142处,二维超声能确诊并与引产及追踪随访结果相符的有115处(81.0%),三维超声则为133... 相似文献
992.
Analysis of cell free fetal DNA (cffDNA) in maternal plasma provides the opportunity for reliable, timely, safe and cost-effective diagnosis of single gene disorders. The detection of certain fetal loci using cffDNA and conventional molecular analytic approaches is possible from 4 weeks gestation. To date, non-invasive first-trimester analysis for single gene disorders has been limited by assay sensitivity and specificity, due to the background maternal DNA. The anticipated ability to enrich the fetal component of cell free DNA will increase the robustness of tests and permit semi-quantitative analysis, broadening the scope of testing to include recessive disorders such as cystic fibrosis. Testing for large-scale mutations might remain limited by the fragmented nature of cffDNA and, when testing very early in gestation, careful ultrasound examination will be needed to determine the number of gestational sacs, because of the risk of discordant twin pregnancies. 相似文献
993.
Exposure to Bisphenol A prenatally or in adulthood promotes T(H)2 cytokine production associated with reduction of CD4CD25 regulatory T cells 总被引:1,自引:0,他引:1
BACKGROUND: Bisphenol A (BPA) is a widespread endocrine-disrupting chemical that can affect humans and animals. OBJECTIVES: We investigated the effects of adult or prenatal exposure to BPA on T-helper (T(H))1/T(H)2 immune responses and the mechanisms underlying these effects. METHODS: To evaluate the effects of exposure to BPA in adulthood, male Leishmania major-susceptible BALB/c and -resistant C57BL/6 mice were subcutaneously injected with 0.625, 1.25, 2.5, and 5 mumol BPA 1 week before being infected with L. major. To evaluate prenatal exposure, female mice were given BPA-containing drinking water at concentrations of 1, 10, and 100 nM for 2 weeks, then mated, and given BPA for another week. Male 10-week-old offspring were infected with L. major. Footpad swelling was assessed as a measure of the course of infection. RESULTS: Mice exposed to BPA prenatally or in adulthood showed a dose-dependent increase in footpad swelling after being infected with L. major. Exposure to BPA in adulthood significantly promoted antigen-stimulated production of interleukin (IL)-4, IL-10, and IL-13 but not interferon-gamma (IFN-gamma). However, mice prenatally exposed to BPA showed increased production of not only IL-4 but also IFN-gamma. The percentages of CD4(+)CD25(+) cells were decreased in mice exposed to BPA either prenatally or in adulthood. Effects of prenatal BPA exposure were far more pronounced than effects of exposure in adulthood. CONCLUSION: BPA promotes the development of T(H)2 cells in adulthood and both T(H)1 and T(H)2 cells in prenatal stages by reducing the number of regulatory T cells. 相似文献
994.
Andersen HR Schmidt IM Grandjean P Jensen TK Budtz-Jørgensen E Kjaerstad MB Baelum J Nielsen JB Skakkebaek NE Main KM 《Environmental health perspectives》2008,116(4):566-572
Objectives
The aim of this prospective study was to investigate whether occupational pesticide exposure during pregnancy causes adverse effects on the reproductive development in the male infants.Design and measurements
Pregnant women employed in greenhouses in Denmark were consecutively recruited, and 113 mother–son pairs were included. The mothers were categorized as occupationally exposed (91 sons) or unexposed (22 sons) to pesticides during pregnancy. Testicular position and volume, penile length, and position of urethral opening were determined at 3 months of age using standardized techniques. Concentrations of reproductive hormones in serum from the boys were analyzed.Results
The prevalence of cryptorchidism at 3 months of age was 6.2% [95% confidence interval (CI), 3.0–12.4]. This prevalence was considerably higher than among Danish boys born in the Copenhagen area (1.9%; 95% CI, 1.2–3.0) examined by the same procedure. Boys of pesticide-exposed mothers showed decreased penile length, testicular volume, serum concentrations of testosterone, and inhibin B. Serum concentrations of sex hormone-binding globulin, follicle-stimulating hormone, and the luteinizing hormone:testosterone ratio were increased compared with boys of nonexposed mothers. For individual parameters, only the decreased penile length was statistically significant (p = 0.04). However, all observed effects were in the anticipated direction, and a joint multivariate test showed that this finding had a p-value of 0.012.Conclusions
Our findings suggest an adverse effect of maternal occupational pesticide exposure on reproductive development in the sons despite current greenhouse safeguards and special measures to protect pregnant women. 相似文献995.
[目的]探讨孕期吸烟与先天性腹裂胎儿的关系,分析不同孕期和每天不同吸烟量对先天性腹裂的影响。[方法]分别检索6个中英文文献数据库,选择6篇符合纳入标准的文献,通过Review Manager 4.2和Stata软件进行Meta分析。[结果]孕期吸烟与先天性腹裂胎儿之间的合并效应值为OR=2.36(95%CI:2.02~2.76);每天吸烟量为10~20支及〉20支的合并效应值分别为OR=2.29(95%CI:1.89~2.77)和OR=2.54(95%CI:1.68~3.85),吸烟量〈10支的无统计学意义;孕期前三个月吸烟的合并效应值为OR=2.46(95%CI:1.52~3.98)。[结论]孕期吸烟尤其孕期前三个月吸烟与先天性腹裂胎儿具有显著相关性,此相关性随每天吸烟量的增加而增大。 相似文献
996.
Natalia Forgacova Juraj Gazdarica Jaroslav Budis Jan Radvanszky Tomas Szemes 《Oncology Letters》2021,22(5)
In our previous work, genomic data generated through non-invasive prenatal testing (NIPT) based on low-coverage massively parallel whole-genome sequencing of total plasma DNA of pregnant women in Slovakia was described as a valuable source of population specific data. In the present study, these data were used to determine the population allele frequency of common risk variants located in genes associated with colorectal cancer (CRC) and Lynch syndrome (LS). Allele frequencies of identified variants were compared with six world populations to detect significant differences between populations. Finally, variants were interpreted, functional consequences were searched for and clinical significance of variants was investigated using publicly available databases. Although the present study did not identify any pathogenic variants associated with CRC or LS in the Slovak population using NIPT data, significant differences were observed in the allelic frequency of risk CRC variants previously reported in genome-wide association studies and common variants located in genes associated with LS. As Slovakia is one of the leading countries with the highest incidence of CRC among male patients in the world, there is a need for studies dedicated to investigating the cause of such a high incidence of CRC in Slovakia. The present study also assumed that extensive cross-country data aggregation of NIPT results would represent an unprecedented source of information concerning human genome variation in cancer research. 相似文献
997.
Rosemary Castorina Asa Bradman Laura Fenster Dana Boyd Barr Roberto Bravo Michelle G. Vedar Martha E. Harnly Thomas E. McKone Ellen A. Eisen Brenda Eskenazi 《Environmental health perspectives》2010,118(6):856-863
Background
We measured 34 metabolites of current-use pesticides and other precursor compounds in urine samples collected twice during pregnancy from 538 women living in the Salinas Valley of California, a highly agricultural area (1999–2001). Precursors of these metabolites included fungicides, carbamate, organochlorine, organophosphorus (OP), and pyrethroid insecticides, and triazine and chloroacetanilide herbicides. We also measured ethylenethiourea, a metabolite of the ethylene-bisdithiocarbamate fungicides. Repeat measurements of the compounds presented here have not been reported in pregnant women previously. To understand the impact of the women’s regional environment on these findings, we compared metabolite concentrations from the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) cohort with U.S. national reference data for 342 pregnant women sampled by the National Health and Nutrition Examination Survey (1999–2002).Results
The eight metabolites detected in > 50% of samples [2,4-dichlorophenol (2,4-DCP); 2,5-dichlorophenol (2,5-DCP); 1- and 2-naphthol; ortho-phenylphenol (ORTH); para-nitrophenol (PNP); 2,4,6-trichlorophenol (2,4,6-TCP); and 3,4,6-trichloro-2-pyridinol (TCPy)] may be related to home or agricultural pesticide use in the Salinas Valley, household products, and other sources of chlorinated phenols. More than 78% of women in this study had detectable levels of at least one of the OP pesticide-specific metabolites that we measured, and > 30% had two or more. The 95th percentile values of six of the most commonly detected (> 50%) compounds were significantly higher among the CHAMACOS women after controlling for age, race, socioeconomic status, and smoking [(2,4-DCP; 2,5-DCP; ORTH; PNP; 2,4,6-TCP; and TCPy); quantile regression p < 0.05].Conclusions
Findings suggest that the CHAMACOS cohort has an additional burden of precursor pesticide exposure compared with the national sample, possibly from living and/or working in an agricultural area. 相似文献998.
Raul Harari Jordi Julvez Katsuyuki Murata Dana Barr David C. Bellinger Frodi Debes Philippe Grandjean 《Environmental health perspectives》2010,118(6):890-896
Background
The long-term neurotoxicity risks caused by prenatal exposures to pesticides are unclear, but a previous pilot study of Ecuadorian school children suggested that blood pressure and visuospatial processing may be vulnerable.Objectives
In northern Ecuador, where floriculture is intensive and relies on female employment, we carried out an intensive cross-sectional study to assess children’s neurobehavioral functions at 6–8 years of age.Methods
We examined all 87 children attending two grades in the local public school with an expanded battery of neurobehavioral tests. Information on pesticide exposure during the index pregnancy was obtained from maternal interview. The children’s current pesticide exposure was assessed from the urinary excretion of organophosphate metabolites and erythrocyte acetylcholine esterase activity.Results
Of 84 eligible participants, 35 were exposed to pesticides during pregnancy via maternal occupational exposure, and 23 had indirect exposure from paternal work. Twenty-two children had detectable current exposure irrespective of their prenatal exposure status. Only children with prenatal exposure from maternal greenhouse work showed consistent deficits after covariate adjustment, which included stunting and socioeconomic variables. Exposure-related deficits were the strongest for motor speed (Finger Tapping Task), motor coordination (Santa Ana Form Board), visuospatial performance (Stanford-Binet Copying Test), and visual memory (Stanford-Binet Copying Recall Test). These associations corresponded to a developmental delay of 1.5–2 years. Prenatal pesticide exposure was also significantly associated with an average increase of 3.6 mmHg in systolic blood pressure and a slight decrease in body mass index of 1.1 kg/m2. Inclusion of the pilot data strengthened these results.Conclusions
These findings support the notion that prenatal exposure to pesticides—at levels not producing adverse health outcomes in the mother—can cause lasting adverse effects on brain development in children. Pesticide exposure therefore may contribute to a “silent pandemic” of developmental neurotoxicity. 相似文献999.
1000.
目的探讨无创产前基因检测技术在筛查胎儿染色体非整倍体中的作用。 方法选择需做产前诊断的74名孕妇,采用高通量基因测序技术检测母体血浆胎儿游离DNA,分析胎儿染色体拷贝数。依据患者产前诊断的临床指征分为4个组(高龄妊娠组、母体血清筛查高危组、B超胎儿异常组及生育过21-三体患儿组),计算每组高危患者的比率。对无创产前基因检测显示胎儿染色体非整倍体高危的11例患者,行羊膜腔穿刺进行胎儿染色体核型分析。 结果在各组中显示胎儿染色体非整倍体高危的比率是:高龄妊娠组10.50%(4/38),母体血清高危组17.40%(4/23),B超异常组30.00%,生育过21三体患儿组0.00%(0/3),总高危率14.90%(11/74)。在11例无创产前基因检测显示胎儿染色体非整倍体高危患者中,9例的无创产前筛查结果与胎儿染色体核型一致,一致率81.80%。2例患者为假阳性。 结论无创产前基因检测技术是一种筛查胎儿染色体非整倍体的有效方法,其在胎儿染色体异常疾病的产前检测中具有广泛的应用前景。 相似文献