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Strom CM Strom S Levine E Ginsberg N Barton J Verlinsky Y 《American journal of obstetrics and gynecology》2000,182(6):1629-1632
OBJECTIVE: We sought to determine whether preimplantation genetic diagnosis is associated with particular pregnancy or delivery complications. STUDY DESIGN: A total of 102 consecutive pregnancies after preimplantation genetic diagnosis by polar body removal performed at Illinois Masonic Medical Center resulting in 114 live births were analyzed. All patients were given a delivery and newborn questionnaire, and attempts were made to contact and question them regarding any pregnancy complications and type of delivery. Permission was obtained to examine medical records and discuss the patient's pregnancy with her obstetrician when questions existed with respect to complications or indication for cesarean delivery. RESULTS: Delivery and newborn questionnaires were completed or telephone contact was achieved for 100 of the 102 pregnancies. There were 85 singleton, 9 twin, and 7 triplet pregnancies. Of the 7 triplet gestations, 3 couples elected multifetal pregnancy reduction to twins and healthy triplets were born to 4 couples between 32 and 36 weeks by cesarean delivery. Of the 80 singleton deliveries, 60 (75%) progressed to term. Of these 60 term singleton deliveries, 34 were vaginal, 23 were cesarean (40%), and 3 delivery types were unknown. The incidence of small-for-gestational-age infants was 3% for neonates in the 60 term singleton deliveries and 7% in the entire cohort of 80 singleton deliveries. Only 3 pregnancy complications (other than premature delivery) were reported more than once. There were 3 instances each of gestational diabetes, intrauterine growth restriction, and pregnancy-induced hypertension. There was 1 case each of HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome, congestive heart failure, mild oligohydramnios, and abruptio placentae. The indications for cesarean delivery were (in descending order) failure of labor to progress (n = 7), fetal distress (n = 4), placenta previa (n = 4), elective repeat cesarean delivery (n = 4), triplets (n = 3), uterine scarring (n = 3), 1 twin in the breech position (n = 3), failed forceps delivery (n = 2), and a variety of other indications that occurred in only 1 patient each. All preimplantation genetic diagnoses were confirmed by prenatal or postnatal testing. No diagnostic errors were made in this cohort of patients or in any patients undergoing preimplantation genetic diagnosis having polar body removal in our center. CONCLUSIONS: Preimplantation genetic diagnosis is associated with a risk of multiple gestations, cesarean delivery, and placenta previa. Cesarean delivery rates and multiple gestation rates are comparable to those of patients undergoing in vitro fertilization in general. The preimplantation genetic diagnosis itself does not seem to cause an increased risk for any particular pregnancy complication, with the possible exception of placenta previa, which was seen in 4% of patients. 相似文献
213.
利用电磁场理论,假定单分子层膜凝聚相是单轴晶体,在4×4矩阵方法的基础上,给出了单色平面P偏光以布儒斯特角入射时,经单分子层膜和水相体系反射后的光强表达式。利用检偏角的变化,对布儒斯特显微镜(BAM)图像像素点所代表分子簇的极化倾角和取向方位角进行了参数估计。结果表明:当目标函数取阈值10-40时,此方法的正确概率为0.972 4;取消目标函数阈值的正确概率可提高到0.977 1;若同时增大迭代步数可使正确估计概率提高到0.992 7;增加至6个检偏角,则可给出任意一组极化倾角和取向方位角的正确值。该算法为从BAM图像获取Lang-muir单分子膜的微观分子取向信息提供了一种可能的途径。 相似文献
214.
Polar body diagnosis of common aneuploidies by FISH 总被引:6,自引:0,他引:6
Yury Verlinsky Jeanine Cieslak Michael Freidine Victor Ivakhnenko George Wolf Larissa Kovalinskaya Melody White Aaron Lifchez Brian Kaplan Jacob Moise Jorge Valle Norman Ginsberg Charles Strom Anver Kuliev 《Journal of assisted reproduction and genetics》1996,13(2):157-162
Purpose: The purpose of this work was to investigate the reliability and accuracy of polar body analysis for preimplantation diagnosis of common aneuploidies in IVF patients of advanced maternal age.
Design: We have previously introduced polar body analysis as an approach for nondestractive evaluation of the genotype of human oocytes. The method has recently been applied in a clinical trial involving 45 infertile patients, demonstrating the feasibility of preconception diagnosis of common aneuploidies by fluorescent in situ hybridization (FISH). The present paper describes the experience of polar body diagnosis in 135 IVF patients (161 cycles) of advanced maternal age.
Results: FISH results of the first and/or second polar bodies were available in 648 (72.4%) of 895 biopsied oocytes subjected to FISH analysis. Of 648 oocytes with FISH results, 208 demonstrated chromosomal abnormalities. Of 440 oocytes predicted to be free from monosomy or trisomy of chromosomes X, 18, and/or 13/21, 314 were normally fertilized, cleaved, and transferred in 122 treatment cycles, resulting in 6 healthy deliveries and 12 ongoing pregnancies following confirmation of the polar body diagnosis by CVS or amniocentesis.
Conclusion: The method may be useful for detection of oocytes with common chromosomal trisomies in IVF patients of advanced maternal age.Presented at the 5th Annual Meeting of the International Working Group on Preimplantation Genetics, Hamburg, Germany, June 28, 1995. 相似文献
215.
Animals pretreated with chlordecone exhibit a greatly increased hepatotoxic response to CCl4 challenge. Possible mechanisms underlying this interaction were examined. A single p.o. administration of chlordecone (5 mg/kg) was followed by CCl4 (200 μl/kg) administered i.p. 48 h later. Twenty-four hours later, animals treated with chlordecone + CCl4 had decreased hepatic excretory function (20% of controls) and elevated plasma transaminase activities and bilirubin. Hepatic mixed function oxidase activity was assessed as pentobarbital sleeping time and was not affected by chlordecone pretreatment. Irreversible binding of label from 14CCl4 to hepatic protein or lipid was not different in the chlordecone group compared to vehicle controls. Hepatic and renal glutathione concentrations were not affected by chlordecone alone (at 6 h, 1, 2, 3, 5 and 7 days) or by a combination of chlordecone (48 h) and CCl4 (24 h). CCl4-induced lipid peroxidation of liver tissue, measured in vitro or in vivo, was not increased by chlordecone treatment. Thus, while the mechanism for the enhanced toxicity remains to be elucidated, these results suggest that the interaction between chlordecone and CCl4 is a subtle one, not causally involving increased covalent binding of the toxin, increased susceptibility of tissue lipids to peroxidative damage or decreased hepatic GSH. 相似文献
216.
目的:探讨金雀异黄素(Gen)对小鼠卵母细胞成熟的影响.方法:用不同浓度的Gen给小鼠腹腔注射后,检测Gen对卵母细胞生发泡破裂(GVBD)、第一极体(PB1)释放、体外受精和胚胎发育等的影响;用含不同浓度的Gen的培养液培养小鼠未成熟卵母细胞,观察卵母细胞GVBD、PB1释放的发生率;结果:腹腔注射Gen可以增加小鼠子宫湿重,增加小鼠的超排卵数(除高剂量组外)、影响卵母细胞体内成熟过程中的GVBD和第一极体的释放(Gen-0.5组除外),高剂量组小鼠成熟卵母细胞的受精能力和胚胎发育能力均下降.Gen以剂量依赖的方式抑制体外培养小鼠未成熟卵母细胞的GVBD和PB1的释放.结论:Gen能够可逆性地抑制小鼠未成熟卵母细胞的成熟,高剂量的Gen可能影响卵母细胞减数分裂过程,降低卵母细胞的受精能力,提示育龄妇女摄人过量Gen及其化合物可能会导致生育能力降低,甚至造成不育或不孕. 相似文献
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219.
倪俊声 《第二军医大学学报》2021,42(11)
目的 了解北极特殊环境对科考队人员睡眠质量的影响。方法 应用匹兹堡睡眠质量指数(PSQI)量表对我国第9次北极科学考察队队员(131人)在出行前、北极考察期间、考察结束后的睡眠情况进行调查,并记录队员的入睡时间点、晨起时间点、入睡时间、实际睡眠时间、白天睡眠时间。分析人员基本情况因素(年龄、性别、慢性疾病、使用药物情况等),北极特殊环境因素(执行任务时间,与地磁北极点距(高低纬度差异)等)等,干预措施因素(安眠药物、行为疗法)与人员睡眠质量的相关性,并通过多因素分析找出影响北极人员睡眠质量的独立危险因素。结果 共发放问卷131份,回收有效问卷88名,其中男77名、女11名,年龄为22~50(48.1±17.9)岁,包括船员18人、科考队员70人。航行中晨起时间点比航行前/后早了近180min、入睡时间行前、行中、行后分别为[(18.45±14.34)min vs(45.23±25.84)min vs(19.50±12.57)min,行前vs行中 p<0.01, 行后vs行中p<0.01],夜间实际睡眠时间分别为[(8.36±1.45)h vs(6.83±2.24)h vs (8.14±1.45)h,行前vs行中 p<0.01, 行后vs行中p<0.01]。根据PSQI主观量表评分,考察期间队员的睡眠质量下降、入睡时间延长、睡眠时间缩短、睡眠效率下降、催眠药物使用增加,与出行前相比差异均有统计学意义(P均<0.01)。结论 极地极昼环境以及低温显著影响队员睡眠的规律性,延长入睡时间,缩短睡眠时间,增加助眠药物使用量,从而可能影响到队员的工作状态。 相似文献
220.
Raúl Frances Ana M. Rodriguez Benitez Daniel R. Cohen 《American journal of medical genetics. Part A》1997,73(2):125-126
Arrythmogenic right ventricular dysplasia (ARVD) is an autosomal dominant inherited cardiomyopathy with incomplete penetrance and variable expressivity. Recently, the gene was mapped to 14q23–24. It is being increasingly investigated as a major cause of sudden death at a young age. Anterior polar cataract (APC) is a rare hereditary form of lens opacity. The locus for an APC gene was located tentatively on 14q24qter. We describe a patient with a severe form of ARVD in whom asymptomatic APC was detected by an ophthalmologic examination. His sister had ARVD and similar cataracts. Parents were second cousins but were healthy. This is the first report of possible autosomal recessive inheritance of ARVD. This is also the first time that the combination of ARVD and APC is reported. Three possibilities may explain this concurrence: pleiotropy, contiguous gene syndrome, or coincidence. Our findings suggest placement of an APC gene at 14q23–24. Am. J. Med. Genet. 73:125–126, 1997. © 1997 Wiley-Liss, Inc. 相似文献