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151.
Female fragile X premutation carriers are at ∼10-fold increased risk of premature ovarian failure (follicle stimulating hormone >40 mIU/mL, amenorrhea, age <40). A milder degree of premature ovarian aging (diminished ovarian reserve, where follicle stimulating hormone levels are typically 10–20 mIU/mL) results in infertility. Approximately 10% of fertility clinic patients have this diagnosis. A cohort of 20 women diagnosed with diminished ovarian reserve provided a blood specimen (confidential results), and completed structured questionnaires that assessed emotional reactions to potentially being a premutation carrier (pretest questionnaire, n = 20) and the posttest known carrier status (3 month follow-up questionnaire, n = 18 non-carriers). Responses were measured using 9-point scales, and analyzed with Fisher exact and Wilcoxon exact tests. While most participants did not view fragile X premutations as a serious medical condition, perceptions of seriousness were positively correlated with anger and regret about not knowing sooner of the potential association of these premutations with infertility. Overall, when women (pretest) imagined themselves as carriers, their self-esteem and Health Orientation Scale responses were unchanged with the exception of feeling more afraid (p = 0.004). Despite strongly wishing for negative test results, they were glad to know there might be a medical explanation for their infertility. Financial Support: This work was financially supported by a University of Virginia School of Medicine Research & Development Award.  相似文献   
152.
From insects to humans, successful navigation relies on retained representations of spatial relations. These representations are thought to depend on the hippocampal formation, particularly those that are independent of the navigator (allocentric representations). The Morris water maze is a simple and popular task often used to assess spatial navigation. But how animals navigate toward and retain information regarding the location of the goal in this task remains unclear. We provide a comprehensive account of how the water maze is accomplished behaviourally. Our findings suggest that animals solve the task using distal cues via an initial view-matching strategy that is supported by egocentric guidance. Through increased training, however, an emergence of an egocentric-guiding strategy combined with the animal’s greater ability to infer the hidden platform’s location (via allocentric extrapolation) emerges. We also demonstrate that behavioural changes, towards a more allocentric strategy, are reflected in increases in hippocampal brain-derived neurotrophic factor.  相似文献   
153.
Despite the advent of CRISPR, safe and effective gene editing for human enhancement remains well beyond our current technological capabilities. For the discussion about enhancing human beings to be worth having, then, we must assume that gene-editing technology will improve rapidly. However, rapid progress in the development and application of any technology comes at a price: obsolescence. If the genetic enhancements we can provide children get better and better each year, then the enhancements granted to children born in any given year will rapidly go out of date. Sooner or later, every modified child will find him- or herself to be “yesterday’s child.” The impacts of such obsolescence on our individual, social, and philosophical self-understanding constitute an underexplored set of considerations relevant to the ethics of genome editing.  相似文献   
154.
采用环境×基因×环境(E×G×E)研究设计, 以637名青少年为被试, 考察了负性生活事件、COMT基因Val158Met多态性和父母教养行为对青少年早期抑郁的影响。结果发现:负性生活事件对青少年早期抑郁具有显著正向预测作用, 且COMT基因Val158Met多态性和父亲积极教养行为在其中起调节作用, 但该调节作用仅存在于男青少年群体中:在携带Val/Val基因型的男青少年中, 当父亲积极教养行为水平较低时, 青少年的抑郁水平随负性生活事件的增多而显著上升, 当父亲积极教养行为水平较高时, 负性生活事件对抑郁无显著预测作用; 在携带Met等位基因的男青少年中, 上述交互作用不显著。  相似文献   
155.
情绪应激对不同脑区c-fos表达的影响   总被引:4,自引:1,他引:4  
利用电击信号和空瓶刺激两种情绪应激体液免疫调节作用动物模型,以c-fos原癌基因为探针,观察情绪应激后2个小时,大鼠全脑的c—fos原癌基因表达情况,探讨情绪应激对不同脑区c—fos表达的影响。结果表明,电击信号和空瓶刺激两种情绪应激源均能引起某些脑区或核团的c—fos蛋白表达明显增加,包括额皮质、扣带皮质、杏仁内侧核、前连合核、下丘脑背内侧核弥散部、弓状核、孤束核。结果提示,这些脑区或核团是情绪应激主要激活的中枢部位。  相似文献   
156.
基因治疗是一种新的有希望的抗肿瘤治疗方法。本文首先简述基因治疗发展史,然后介绍目前尝试性用于血液系统肿瘤的反义核酸疗法、抑癌基因疗法、自杀基因疗法以及过继性免疫疗法等基因治疗方法,进一步阐述基因治疗在血液系统肿瘤患者中应用存在的伦理学问题。  相似文献   
157.
DNA双螺旋结构发现者之一、美国著名生物学家沃森的<基因·女郎·伽莫夫:发现双螺旋之后>一书,以亲身的经历和感受生动地描述了科学家之间微妙的合作和激烈的竞争,说明了科学是严肃而神圣的,科学家的生活却是丰富多彩的.  相似文献   
158.
This paper focuses on the question of whether DNA patents help or hinder scientific discovery and innovation. While DNA patents create a wide variety of possible benefits and harms for science and technology, the evidence we have at this point in time supports the conclusion that they will probably promote rather than hamper scientific discovery and innovation. However, since DNA patenting is a relatively recent phenomena and the biotechnology industry is in its infancy, we should continue to gather evidence about the effects of DNA patenting on scientific innovation and discovery as well the economic, social, and legal conditions relating to intellectual property in biotechnology. We should give the free market, the courts, researchers, and patent offices a chance to settle issues related to innovation and discovery, before we seek legislative remedies, since new laws proposed at this point would lack adequate foresight and could do more harm than good. However, we should be open to new laws or regulations on DNA patents if they are required to in order to deal with some of the biases and limitations of the free market.  相似文献   
159.
Background and Objectives: Excessive worry is associated with a range of psychological disorders. While previous studies have examined genes associated with a range of different anxiety phenotypes, none have explored genes specifically associated with the general tendency to worry. Design: The present study tested associations between trait worry and functional polymorphisms of three candidate genes: the serotonin transporter-linked polymorphic region (5-HTTLPR) of the SLC6A4 gene, the Val66Met region of the brain-derived neurotrophic factor (BDNF) gene, and the Val158Met region of the catechol-O-methyltransferase (COMT) gene. Methods: A heterogeneous sample of adult participants (n = 173) completed the Penn State Worry Questionnaire (PSWQ) and provided DNA samples for genotyping. Results: Results revealed a significant interaction between 5-HTTLPR and BDNF genotypes predicting levels of worry. Specifically, there was a significant positive association between 5-HTTLPR short alleles and PSWQ scores, but only in BDNF met allele carriers. COMT genotype was not significantly associated levels of worry, nor did COMT interact with 5-HTTLPR or BDNF genotypes to predict PSWQ scores. Conclusions: These findings provide preliminary evidence about the putative genetic etiology of worrying. Key limitations of the present study and corresponding directions for future research on this topic are discussed.  相似文献   
160.
由于关节软骨主要是由软骨细胞和周围的外基质组成的无血管组织,损伤后自我修复能力比较弱,利用基因转染技术治疗软骨损伤性疾病是基因工程研究的重点,而软骨细胞和骨髓间充质干细胞(BMSCs)是基因转染技术中最主要和最常用的种子细胞,与之相关的基因转染的研究也是目前研究的热点。本文拟就与软骨细胞和BMSCs相关的基因转染方面(包括病毒载体、单基因转染和多基因转染)取得的成果和最新研究进展作一综述。  相似文献   
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