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951.
The objective of this study was to analyze genome-wide differential methylation patterns in maternal leukocyte DNA in early pregnant and non-pregnant states. This is an age and body mass index matched case-control study comparing the methylation patterns of 27,578 cytosine-guanine (CpG) sites in 14,495 genes in maternal leukocyte DNA in early pregnancy (n = 14), in the same women postpartum (n = 14), and in nulligravid women (n = 14) on a BeadChip platform. Transient widespread hypomethylation was found in early pregnancy as compared with the non-pregnant states. Methylation of nine genes was significantly different in early pregnancy compared with both postpartum and nulligravid states (< 10% False Discovery Rate). Early pregnancy may be characterized by widespread hypomethylation compared with non-pregnant states; there is no apparent permanent methylation imprint after a normal term gestation. Nine potential candidate genes were identified as differentially methylated in early pregnancy and may play a role in the maternal adaptation to pregnancy.  相似文献   
952.
Incubation temperature influences a suite of traits in avian offspring. However, the mechanisms underlying expression of these phenotypes are unknown. Given the importance of thyroid hormones in orchestrating developmental processes, we hypothesized that they may act as an upstream mechanism mediating the effects of temperature on hatchling phenotypic traits such as growth and thermoregulation. We found that plasma T3, but not T4 concentrations, differed among newly hatched wood ducks (Aix sponsa) from different embryonic incubation temperatures. T4 at hatching correlated with time spent hatching, and T3 correlated with hatchling body condition, tarsus length, time spent hatching and incubation period. In addition, the T3 : T4 ratio differed among incubation temperatures at hatch. Our findings are consistent with the hypothesis that incubation temperature modulates plasma thyroid hormones which in turn influences multiple aspects of duckling phenotype.  相似文献   
953.
Dispersal capacity is a key life‐history trait especially in species inhabiting fragmented landscapes. Evolutionary models predict that, given sufficient heritable variation, dispersal rate responds to natural selection imposed by habitat loss and fragmentation. Here, we estimate phenotypic variance components and heritability of flight and resting metabolic rates (RMRs) in an ecological model species, the Glanville fritillary butterfly, in which flight metabolic rate (FMR) is known to correlate strongly with dispersal rate. We modelled a two‐generation pedigree with the animal model to distinguish additive genetic variance from maternal and common environmental effects. The results show that FMR is significantly heritable, with additive genetic variance accounting for about 40% of total phenotypic variance; thus, FMR has the potential to respond to selection on dispersal capacity. Maternal influences on flight metabolism were negligible. Heritability of flight metabolism was context dependent, as in stressful thermal conditions, environmentally induced variation dominated over additive genetic effects. There was no heritability in RMR, which was instead strongly influenced by maternal effects. This study contributes to a mechanistic understanding of the evolution of dispersal‐related traits, a pressing question in view of the challenges posed to many species by changing climate and fragmentation of natural habitats.  相似文献   
954.

AIM:

The presence of circulatory cell-free fetal DNA in maternal plasma has found new applications in non-invasive risk-free prenatal diagnosis.

MATERIALS AND METHODS:

We made use of a size separation approach along with real time polymerase chain reaction (PCR) to evaluate the use of fetal DNA in the detection of the sex of the fetus. Cell-free fetal DNA was isolated from the plasma of 30 women (10–20 weeks gestation) using a size separation approach. We made use of Taq Man Chemistry and real time PCR using primers and probes for GAPDH and SRY.

RESULTS:

Only 24 cases could be studied as there was no amplification in six cases. Fetal sex was accurately determined in all of the 24 cases wherein 19 women were carrying male fetuses and five women were carrying female fetuses. An increase in the amount of fetal DNA was observed with an increase in the gestational age.

CONCLUSIONS:

Real time PCR analysis is a highly sensitive and accurate tool for non-invasive prenatal diagnosis, allowing detection of the sex of the fetus as early as 10 weeks of gestation. Non-invasive prenatal diagnosis eliminates the risk of fetal loss associated with the invasive procedure.  相似文献   
955.
[背景]深海热液环境中存在大量H2S及含硫化合物,许多微生物与大型生物形成了紧密的共生体系,例如硫氧化细菌,它们利用其独特的代谢体系协助宿主更好地适应极端环境,但目前尚未对热液底栖生物共附生的硫氧化细菌进行培养鉴定和功能分析.[目的]了解深海热液生物共附生硫氧化细菌的种群特征和功能特征,筛选出深海热液生物共附生微生物中...  相似文献   
956.
ABSTRACT

The objectives of the present study were to quantify the deposition of carotenoids and tocopherols in the tissues of suckling lamb and to use the levels of those compounds to trace the maternal feeding. Twenty suckling lambs were raised with their dams in vegetative-stage pastures, and 19 suckling lambs were stalled indoors with dams that received hay ad libitum, until the lambs reached 10–12 kg. The lambs’ weekly intake of carotenoids and tocopherols was estimated from the milk production of the ewes and the carotenoid and tocopherol content of the milk. Samples of the subcutaneous and perirenal fat, longissimus thoracis muscle, and liver of the suckling lambs were collected at 24 h after slaughter. The pasture-raised lambs had greater intake of lutein than their indoor counterparts throughout the suckling period (p < 0.05), more retinol during the second and third weeks of the suckling period (p < 0.05), and more α-tocopherol during the first three weeks of the suckling period (p < 0.05), being similar thereafter. The pasture-raised lambs, when compared to the lambs raised indoors, had greater lutein content in the muscle and liver (p < 0.001), retinol and α-tocopherol content in all tissues (p < 0.001) and muscle and liver γ-tocopherol content (p < 0.05). The maternal feeding could be accurately predicted from the carotenoid and tocopherol content of whole lamb carcasses and muscle tissue but not from those of ewes’ milk, lamb liver tissue or lamb fat deposits.  相似文献   
957.
目的:研究核心稳定性训练(CST)对痉挛型脑性瘫痪(SCP)患儿爬行能力及日常生活活动能力的影响。方法:选择从2015年1月到2017年2月期间在我院接受治疗的SCP患儿134例纳入本次研究,根据随机数字表法将患儿分成观察组及对照组,各67例,对照组给予常规训练,观察组则给予CST,两组均治疗3个月。对比两组疗效、治疗前及治疗3个月后的爬行能力评分以及日常生活活动能力评分。结果:观察组的总有效率是95.52%,明显高于对照组的85.07%,差异有统计学意义(P0.05)。治疗3个月后两组的爬行能力评分均分别高于治疗前,且观察组高于对照组,差异均有统计学意义(均P0.05)。治疗3个月后两组的日常生活活动能力各项评分均分别高于治疗前,且观察组高于对照组,差异均有统计学意义(均P0.05)。结论:CST对SCP患儿的爬行能力及日常生活活动能力具有较好的改善作用,临床治疗过程中可应用此种训练措施强化患儿的运动功能,从而促进其获得更好的预后,值得给予推广。  相似文献   
958.
目的:分析新生儿ABO溶血病的临床相关危险因素,提高对新生儿ABO溶血病的防治水平。方法:选择ABO血型不合的孕妇433例,根据以上产妇产前IgG抗A(B)效价、产妇妊娠次数和产妇年龄分别分组,分析各组产妇间发生新生儿溶血病(HDN)的差异及临床相关性。结果:产妇产前IgG抗A(B)效价、产妇妊娠次数和产妇年龄均与HDN发生率呈正相关性(P<0.05);IgG抗A(B)效价>256时,HDN发生率将显著提高(P<0.01);产妇妊娠次数和年龄增加后,HDN发生率将显著增加(P<0.01)。结论:夫妻血型不合的产妇进行产前保健时,应进行IgG抗A(B)效价检查,当IgG抗A(B)效价>64或IgG抗A(B)效价进行性增加时,应及早做好HDN的干预措施;通过减少意外妊娠及高龄产妇数量,可减少HDN的发生。  相似文献   
959.
Elevated heat shock protein 90 (Hsp90) expression has been linked to poor prognosis in patients with non-small cell lung cancer (NSCLC). The multitargeted antifolate pemetrexed has demonstrated certain clinical activities against NSCLC. However, the efficacy of the combination of pemtrexed and Hsp90 inhibitor to prolong the survival of patients with NSCLC still remains unclear. Human MutS homolog 2 (MSH2), a crucial element of the highly conserved DNA mismatch repair system, and defects or polymorphisms of MSH2 have been found in lung cancer. In this study, we evaluated the effects of pemetrexed on NSCLC cell lines (H520 and H1703) and found that treatment with this drug at 20–50 µM increased the MSH2 mRNA and protein levels in a MKK3/6–p38 MAPK signal activation-dependent manner. Furthermore, the knockdown of MSH2 expression by transfection with small interfering RNA of MSH2 or the blockage of p38 MAPK activation by SB202190 enhanced the cytotoxicity of pemetrexed. Combining the drug treatment with an Hsp90 inhibitor resulted in an enhanced pemetrexed-induced cytotoxic effect, accompanied with the reduction of MSH2 protein and mRNA levels. The expression of constitutively active MKK6 (MKK6E) or HA-p38 MAPK vectors significantly rescued the decreased p38 MAPK activity, and restored the MSH2 protein levels and cell survival in NSCLC cells co-treated with pemetrexed and Hsp90 inhibitor. In this study, we have demonstrated that down-regulation of the MKK3/6–p38 MAPK signal with the subsequent reduction of MSH2 enhanced the cytotoxic effect of pemetrexed in H520 and H1703 cells. The results suggest a potential future benefit of combining pemetrexed and the Hsp90 inhibitor to treat lung cancer.  相似文献   
960.
Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatures during seed production. Here, we have extended these studies by testing the effects of maternal photoperiod and temperature on phenology and frost hardiness on progenies. Using eight phytotron rooms, seeds from three unrelated crosses were made in an environmental 2 x 2 factorial combination of long and short days and high and low temperatures. The progenies were then forced to cease growth rapidly at the end of the first growing season. An interactive memory effect was expressed the second growth season. Progenies from high temperature and short days, and from low temperatures and long days, started growth later in spring, ceased shoot growth later in summer, grew taller and were less frost hardy in the autumn than their full siblings from low temperatures and short days, and from high temperatures and long days. Norway spruce has developed a memory mechanism, regulating adaptive plasticity by photoperiod and temperature, which could counteract harmful effects of a rapidly changing climate.  相似文献   
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