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91.
连青萍 《上海生物医学工程》2010,(1):41-43
目的探讨输卵管妊娠腹腔镜根治术后持续性异位妊娠发生的原因,以寻求针对性的处理方法。方法回顾分析我院2007年1月至2009年1月670例输卵管妊娠患者行腹腔镜下输卵管切除术,术后发生持续性异位妊娠共6例。结果4例采用药物保守治疗成功,2例保守治疗无效行手术治疗后成功。结论在手术过程中尽量避免输卵管妊娠物直接经Troca钳夹取出,防止残留于Troca、勺状钳、冲洗棒头端等操作器械上的绒毛组织再次带入腹腔,可能有助于有效阻断持续性异位妊娠的形成。 相似文献
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表观遗传学研究的是稳定的遗传信息的修饰,这种修饰在不改变DNA序列的情况下引起基因表达和功能的改变。肿瘤发生过程中,经常伴有抑癌基因的表观遗传学修饰,如DNA甲基化、组蛋白去乙酰化等。硫氧还蛋白结合蛋白-2是硫氧还蛋白的结合蛋白质,它可以和还原型的硫氧还蛋白相结合,与肿瘤发生密切相关。本文论述了有关肿瘤表观遗传学、硫氧还蛋白结合蛋白-2的表观遗传学修饰及其与肿瘤的相关性。 相似文献
94.
Beitelshees AL Johnson JA Hames ML Gong Y Cooper-Dehoff RM Wu J Cresci S Ma CX Pepine CJ Province MA Spertus JA McLeod HL 《PloS one》2010,5(12):e15180
Introduction
CYP19A1 encodes aromatase, the enzyme responsible for the conversion of androgens to estrogens, and may play a role in variation in outcomes among men and women with cardiovascular disease. We sought to examine genetic variation in CYP19A1 for its potential role in sex differences in cardiovascular disease outcomes.Methods
Caucasian individuals from two independent populations were assessed: 1) a prospective cohort of patients with acute coronary syndromes with 3-year mortality follow-up (n = 568) and 2) a nested case-control study from a randomized, controlled trial of hypertension patients with stable coronary disease in which the primary outcome was death, nonfatal myocardial infarction (MI) or nonfatal stroke (n = 619). Six CYP19A1 SNPs were genotyped (-81371 C>T, -45965 G>C, M201T, R264C, 80 A>G, and +32226 G>A). The sex*genotype interaction term was assessed for the primary outcome and compared by genotype in men and women when a significant interaction term was identified.Results
We identified a significant interaction between -81371 C>T and sex (p = 0.025) in the ACS population. The variant allele was associated with a 78% increase in mortality in men (HR 1.78, 95% confidence interval [CI] 1.08-2.94) and a nonsignificant 42% decrease in mortality among women (HR 0.58, 95% CI 0.22-1.54). We identified a similar association in the hypertensive CAD group, the -81371 C>T*sex interaction term was p<0.0001, with an associated 65% increase in death, MI, or stroke (HR 1.65, 95% CI 1.00-2.73) in men and a 69% decrease (HR 0.31, 95% CI 0.16-0.6) in women.Conclusions
Using two independent populations, this study is the first to document a significant interaction between CYP19A1 genotype and sex on cardiovascular outcomes. These findings could illuminate potential mechanisms of sex differences in cardiovascular disease outcomes. 相似文献95.
OBJECTIVES: Some traits, while naturally polychotomous, are routinely dichotomized for genetic analysis. Dichotomization, intuitively, leads to a loss of power to detect linkage, as some phenotypic variability is discarded. This paper examines this power loss in the context of a trichotomous trait. METHODS: To examine this power loss, we performed a simulation study where a trichotomous trait was simulated in a sample of 1,000 sib-pairs under various genetic models. The study was replicated 1,000 times. Linkage analysis using a variance components method, as implemented in Mx, was then performed on the trichotomous trait and compared with that on a dichotomized version of the trait. RESULTS: A comparison of the power and false positive rates of the analyses shows that power to detect linkage was increased by up to 22 percentage points simply by examining the trait as a trichotomy instead of a dichotomy. Under all models examined, the trichotomous analysis outperformed the dichotomous version. CONCLUSIONS: Comparable levels of false positive rates under both methods confirm that this power gain comes solely from the information lost upon dichotomization. Thus, dichotomizing tri- or poly-chotomous traits can lead to crippling power loss, especially in the case of many loci of small effect. 相似文献
96.
Ingrid B. Borecki Millicent Higgins Pamela J. Schreiner Donna K. Arnett Elizabeth Mayer-Davis Steven C. Hunt Michael A. Province 《Obesity (Silver Spring, Md.)》1998,6(2):107-114
The body mass index (BMI) is a complex phenotype representing the amount of fat mass, lean mass, body build and proportions, and it is likely to be affected by various metabolic processes, hormonal effects, energy intake and expenditure, and interactions within and among these broad categories of etiologic factors. Nonetheless, several previous studies have reported evidence for major gene segregation for the BMI in various populations. Data on a random sample of Caucasian families participating in the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study were analyzed to document the extent of familial resemblance and to investigate whether a similar monogenic inheritance pattern could be detected. Genetic analysis was carried out on age- and sex-adjusted BMI values. Familial correlations were significant implying a maximal heritability, including all genetic and environmentally inherited additive factors, of 41% to 59%. Segregation analysis revealed the presence of two maximum likelihood solutions, one characterized as a recessive Mendelian gene and the other as a major effect with an ambiguous transmission pattern. The presence of two such solutions is consistent with detection of two separate factors, each influencing the BMI distribution in a substantive manner. The evidence also supports a multifactorial background for BMI and suggests that the frequencies of these two factors, one of which appears to be a gene, may vary among diverse populations in the United States. 相似文献
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新疆若羌石灰华中的植物化石及古环境* 总被引:9,自引:3,他引:6
根据首次从富阳西湖组发现的孢子及其垂直分布特征,划分出下段 LH 组合和上段 DP 组合,分别归入晚泥盆世法门晚期(斯图年期)和早石炭世早期(杜内早期),即泥盆-石炭系界线通过西湖组内部,与江苏五通组类似. 相似文献
99.
江西全南小慕泥盆-石炭系孢子组合及其地层意义 总被引:11,自引:3,他引:8
据30属57种(包含9新种)小孢子的垂直分布特征,将江西全南小慕泥盆一石炭系的小孢子划分为3个组合(自下而上):1)Acanthotriletes denticulatus-Apiculireiusispora raris(DR)组合,2) Leiotriletes macrothlis-Grandispora xiamuensis(MX)组合,uispinosa(TT)组合,3)Apiculiretusisporatera-Lycospora cf. thuispinosa(TT)组合.这3个组合分别产于三门滩组、翻下组与荒塘组-刘家塘组.据孢子资料的分析与植物、腕足类、鱼类等化石的佐证,三门滩组与翻下组的时代均属晚泥盆世晚期(Famennian),荒塘组与刘家塘组属早石炭世早期(Tournaisian).本区泥盆系与石炭系的界线置于翻下组与荒塘组之间较适合. 相似文献
100.