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1.
Finger-prints of the parents of thirty four Down children were compared with thirty four couples with two or more normal children without a family history of genetic problems. The parents with children affected by translocation Down Syndrome and those with mosaicism were excluded. A comparison of the figure distributions in each of the fingers of the two groups shows a different distribution. Parents of children affected by Down Syndrome occupy an intermediate position between the parents of normal children and the subjects affected by Down Syndrome. The total sum of values of A (arch), Lu (ulnar loop), Lt (radial loop) and W in each of the groups were also compared using a contingency table. A significant difference (p<0,05) was found between both groups. The differences are imputed to the variables A and L.  相似文献   
2.
Different factors have been proposed to influence morningness‐eveningness, biological rhythms, and sleep‐wake cycles, but few studies focused on the influence of social habits. Here, we focus on the influence of children and partners on the social habits of women at different stages of their lives and on synchronization within the family. One hundred and seventy‐nine women participated in the study and were allocated into four groups: women without children, pregnant women without children, pregnant women with children, and non‐pregnant mothers. Morningness was predicted by the presence of children, and earlier chronotype was predicted by the presence of children, pregnancy, and age. Average sleep duration was longest in pregnant women. The presence of children was responsible for a difference in rise times of approximately 1.5 h on the weekend. Subjective sleep‐onset latencies were shortest in women with children. The synchrony between partners (husband/wife) was 0.46 in women without children, 0.79 in pregnant women, 0.40 in women with children, and 0.56 between mother and child. Partners’ chronotypes were highly correlated, as were those of mother and child. This study suggests children have a strong influence on their mother's lifestyle and sleep‐wake rhythm, far beyond the first months of life, and that children are a more important social factor than the male partner.  相似文献   
3.
Background: The psychological problems of Shidu Parents (SDP) under the China’s One-Child Policy have been documented. The purpose of this study was to investigate the relationships among personality types, social support, and post-traumatic stress disorder (PTSD) in SDP. Methods: The PTSD Checklist-Civilian Version (PCL-C), The Big Five Personality Traits (NEO), and Social Support Revalued Scale (SSRS) were administered to the sample of 149 SDP who were over 50 years old and had lost their only child more than one year ago. Results: Among SDP, mothers were more likely to develop PTSD than fathers (χ2 = 11.16, p < 0.01). Parents who were extraverted had a lower risk of developing PTSD-related symptoms (χ2 = 8.58, p < 0.01), and the effect of neuroticism was significant (χ2 = 23.73, p < 0.01). The more social support parents utilized, the lower the incidence of PTSD (t = 4.56, p < 0.01). The result of multilevel linear regression showed that sex, neuroticism, and objective social support remained significantly different after combining all personality types and social support systems in the same model. Social support partially mediated the relationship between neuroticism and PTSD. Meanwhile, it was a complete mediator between extraversion and PTSD. Conclusions: Female sex/gender, neuroticism, and introversion were risk factors of developing PTSD, while receiving social support protected SDP from developing PTSD symptoms. Losing an only child is undoubtedly an enormous disaster for the family, which has become a huge, unavoidable social problem that must be addressed in China.  相似文献   
4.
BackgroundConducting clinical trials with pre-term or sick infants is important if care for this population is to be underpinned by sound evidence. Yet, approaching the parents of these infants at such a difficult time raises challenges to obtaining valid informed consent for such research. In this study, we asked, What light does the analytical literature cast on an ethically defensible approach to obtaining informed consent in perinatal clinical trials?MethodsIn a systematic search, we identified 30 studies. We began our analysis by applying philosophical frameworks, which were then refined as concepts emerged from the analytical studies, to present a coherent picture of a broad literature.ResultsBetween them, the studies addressed four themes. The first three were the ethical basis for parental informed consent for neonatal and/or perinatal research, the validity of parental consent in this context, and the range of possible options in methods for gaining consent. The last was the issue of risk and the possibility of a double-standard or asymmetry in the current approaches to the requirement for consent for research and consent for clinical treatment.ConclusionsIn addressing these issues, the analysed studies showed that, whilst there are a variety of possible defences for seeking parental ‘consent’ to neonatal and/or perinatal clinical trials, these are all consistent with the strongly and widely held view that it is important that parents do give (or decline) consent for such research. So far as the method of obtaining consent is concerned, none of the existing consent processes reviewed by the research is satisfactory, and there are philosophical reasons for supposing that at least some parents will fail to give valid consent in a neonatal context. Furthermore, in giving parental ‘consent’ in a perinatal context, parents are authorising infant participation, not giving ‘proxy consent’. Finally, there are reasons for giving weight to both parental ‘consent’ and the infant’s best interests in both research and clinical treatment. However, there are also reasons to treat these factors differently in the two contexts, and this may be partly due to the differing relevance of risk in each case. A significant gap is the lack of any detailed discussion of a process of emergency and/or urgent ‘assent’, in which parents assent or refuse their baby’s participation as best they can during the emergency and later give full consent to continuing participation and follow-up.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1562-3) contains supplementary material, which is available to authorized users.  相似文献   
5.
通过比较观察紫花含笑(♀)和灰岩含笑()及其杂种F1代叶表皮微形态和叶结构发现,紫花含笑和灰岩含笑在叶表皮微形态及叶解剖结构方面有很大差异。杂种F1代个体间在叶表皮微形态及叶解剖结构方面变异很大,为连续的数量遗传;其中57.7%以上的杂种F1代气孔密度高于父母本。杂种F1代矮化型植株叶片气孔密度较小,推测其抗寒性较强,可以通过进一步杂交改良,获得矮化型的盆栽含笑新品种。观察结果可为深入探讨含笑属种间杂种F1代的遗传变异,并从这些杂种F1代中选育观赏新品种积累科学资料。  相似文献   
6.
从形态学看北美红杉的亲本   总被引:2,自引:0,他引:2  
本文通过形态性状的比较研究认为AAAABB的同源异源多倍体红杉可能由亲本水杉(属)和巨杉(属)杂交起源,它们分别为红杉提供了染色体组AA和染色体组B。这与根据核型等资料的分析结果相吻合。但跟Stebbins认为红杉除水杉(属)以外的另一个亲本已经灭绝并没有留下近缘的推论存在分歧。  相似文献   
7.
目的:探讨先天性唇腭裂病的病因,寻找预防办法。方法:对先天性400例唇腭裂手术患者的父母在怀孕前后居住生活、饮食卫生、嗜好、心情精神状态及患病情况做统计分析。结果:400例患者父母怀孕前后居住面积在30m2以下占75%,饮酒吸烟者人数627人中78.3%,女性饮酒167人占41.07%。患普通感冒730人。怀孕在1月内患感冒283人,心情不愉快精神紧张受到不良刺激362人。结论:通过对400例患者父母怀孕前后生活居住患病嗜好精神等因素情况得出结论与外界环境关系密切,尤其怀孕早期患病饮酒吸烟心情不愉快对该病发生起一定作用,但该病是多种原因综合因素所致的一种先天性疾病,具有一定遗传性,但也有可以预防的一方面,在该病发生的过程中有一个主要因素起主导作用,有待今后继续研讨。  相似文献   
8.
用微卫星DNA标记检测中国主要杂交水稻亲本的遗传差异   总被引:35,自引:0,他引:35  
选用分布于水稻(OryzasativaL.)12条染色体上的20对SSR(Simplesequencerepeats)引物,分析了具有多种质源和较大应用面积的24个水稻胞质雄性不育系、1个光(温)敏核不育系、3个保持系和5个生产中应用较广的恢复系。在以上33份杂交水稻亲本材料间共检测出102个等位基因(alleles),平均每对SSR引物可检测到5.1个等位基因。PIC(polymorphicindexcontent)值的变动范围为0.274~0.773,平均PIC值为0.554。从56对SSR引物中筛选出5对引物,能够有效地区分所有供试的水稻雄性不育系和恢复系。杂交水稻亲本的聚类分析表明:(1)我国水稻雄性不育系遗传变异丰富,但生产中主要应用的水稻雄性不育系遗传背景比较单一。(2)生产中应用面积较大的水稻雄性不育系遗传变异较恢复系差。(3)生产中主要应用的水稻雄性不育系与恢复系分别聚类于不同的类群,且遗传关系较远。  相似文献   
9.
甘蔗常用亲本及杂交组合家系评价   总被引:2,自引:0,他引:2  
为评价我国甘蔗亲本的遗传特点和组合的选配效果,采用澳大利亚家系试验法,借助R软件估算亲本的遗传方差、一般配合力(GCA)和组合特殊配合力(SCA)。结果表明:锤度的遗传主要受母本加性基因效应所制约,蔗茎产量主要受母本加性基因效应和非加性基因效应所制约,株高、茎径和有效茎受父母本加性基因效应和非加性基因效应所制约。CP88-2143、ROC10、ROC26、桂糖00-122、粤糖00-318和云蔗99-113作母本,内江57-416、崖城93-26、粤糖91-976和粤糖00-319作父本杂交后代表现出高产高糖,可作为糖能兼用好亲本使用。根据组合特殊配合力效应(SCA),CP88-2143×粤糖00-319、ROC10×粤糖91-976、ROC26×崖城93-26、桂糖00-122×ROC22、粤糖91-976×ROC22、粤糖93-159×内江57-416和云蔗99-113×CP84-1198组合综合表现良好,可作为生产性杂交组合,加大力度使用。  相似文献   
10.
Total thirty throe parents of hybrid rice ( Oryza sativa L. ), including twenty five rice male sterile lines, throe maintainer lines and five restore lines, were analyzed by using twenty SSR (simple sequence repeats) primer pairs which disperse on 12 chromosomes in rice. Those primers detected 102 alleles among 33 parents of hybrid rice. PIC (polymorphic index content) values ranged from 0.274 to 0.773. PIC value is 0.554 on the average. Five SSR primer pairs selected from fifty six primer pairs can distinguish individually all of the rice male sterile lines and restore lines in the present study. As results from cluster analysis, it was concluded as follows. (1) Rice male sterile lines have abundant genetic diversity in China. Genetic background was vulnerable among rice male sterile lines used in large scale. (2) In indica rice, genetic variation of the restored lines is larger than that of the male sterile lines. (3) The restored lines were clustered separately from the male sterile lines which are grown widely for production.  相似文献   
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