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81.
目的:探讨低分子肝素对早发型重度子痫前期治疗情况,并分析治疗对母婴结局的影响。方法:选择我院2012年1月~12月收治的早发型重度子痫前期患者120例,随机分为观察组和对照组,每组60例。对照组给予常规治疗,观察组在对照组治疗基础上加用低分子肝素。比较两组血压、24 h尿量、尿蛋白定量、尿酸、血常规、凝血功能及孕周延长时间、围产儿结局和产妇并发症。结果:两组患者临床指标无差异(P0.05),治疗后两组血压、24 h尿量、尿蛋白定量均显著改善,观察组红细胞压积、纤维蛋白原降低明显高于对照组,而观察组患者的产妇并发症和围产儿不良结局发生率均低于对照组,且产妇孕周延长时间明显多于对照组,差异有统计学意义(P0.05)。两组患者的血小板、凝血酶原时间等治疗前后均无明显变化(P0.05)。结论:低分子肝素对早发型重度子痫前期的治疗能有效抑制高凝状态,改善肾功能,延长孕周时间,可有效减少患者并发症的发生,改善母婴预后,值得临床推广应用。  相似文献   
82.
Birth weight is an economically important trait in pig production because it directly impacts piglet growth and survival rate. In the present study, we performed a genome wide survey of candidate genes and pathways associated with individual birth weight (IBW) using the Illumina PorcineSNP60 BeadChip on 24 high (HEBV) and 24 low estimated breeding value (LEBV) animals. These animals were selected from a reference population of 522 individuals produced by three sires and six dam lines, which were crossbreds with multiple breeds. After quality-control, 43,257 SNPs (single nucleotide polymorphisms), including 42,243 autosomal SNPs and 1,014 SNPs on chromosome X, were used in the data analysis. A total of 27 differentially selected regions (DSRs), including 1 on Sus scrofa chromosome 1 (SSC1), 1 on SSC4, 2 on SSC5, 4 on SSC6, 2 on SSC7, 5 on SSC8, 3 on SSC9, 1 on SSC14, 3 on SSC18, and 5 on SSCX, were identified to show the genome wide separations between the HEBV and LEBV groups for IBW in piglets. A DSR with the most number of significant SNPs (including 7 top 0.1% and 31 top 5% SNPs) was located on SSC6, while another DSR with the largest genetic differences in FST was found on SSC18. These regions harbor known functionally important genes involved in growth and development, such as TNFRSF9 (tumor necrosis factor receptor superfamily member 9), CA6 (carbonic anhydrase VI) and MDFIC (MyoD family inhibitor domain containing). A DSR rich in imprinting genes appeared on SSC9, which included PEG10 (paternally expressed 10), SGCE (sarcoglycan, epsilon), PPP1R9A (protein phosphatase 1, regulatory subunit 9A) and ASB4 (ankyrin repeat and SOCS box containing 4). More importantly, our present study provided evidence to support six quantitative trait loci (QTL) regions for pig birth weight, six QTL regions for average birth weight (ABW) and three QTL regions for litter birth weight (LBW) reported previously by other groups. Furthermore, gene ontology analysis with 183 genes harbored in these 27 DSRs suggested that protein, metal, ion and ATP binding, viral process and innate immune response present important pathways for deciphering their roles in fetal growth or development. Overall, our study provides useful information on candidate genes and pathways for regulating birth weight in piglets, thus improving our understanding of the genetic mechanisms involved in porcine embryonic or fetal development.  相似文献   
83.
How context dependent are species interactions?   总被引:1,自引:0,他引:1  
The net effects of interspecific species interactions on individuals and populations vary in both sign (?, 0, +) and magnitude (strong to weak). Interaction outcomes are context‐dependent when the sign and/or magnitude change as a function of the biotic or abiotic context. While context dependency appears to be common, its distribution in nature is poorly described. Here, we used meta‐analysis to quantify variation in species interaction outcomes (competition, mutualism, or predation) for 247 published articles. Contrary to our expectations, variation in the magnitude of effect sizes did not differ among species interactions, and while mutualism was most likely to change sign across contexts (and predation least likely), mutualism did not strongly differ from competition. Both the magnitude and sign of species interactions varied the most along spatial and abiotic gradients, and least as a function of the presence/absence of a third species. However, the degree of context dependency across these context types was not consistent among mutualism, competition and predation studies. Surprisingly, study location and ecosystem type varied in the degree of context dependency, with laboratory studies showing the highest variation in outcomes. We urge that studying context dependency per se, rather than focusing only on mean outcomes, can provide a general method for describing patterns of variation in nature.  相似文献   
84.
Coevolutionary theory predicts that the most common long‐term outcome of the relationships between brood parasites and their hosts should be coevolutionary cycles based on a dynamic change selecting the currently least‐defended host species, given that when well‐defended hosts are abandoned, hosts will be selected to decrease their defences as these are usually assumed to be costly. This is assumed to be the case also in brood parasite‐host systems. Here I examine the frequency of the three potential long‐term outcomes of brood parasite–host coevolution (coevolutionary cycles, lack of rejection, and successful resistance) in 182 host species. The results of simple exploratory comparisons show that coevolutionary cycles are very scarce while the lack of rejection and successful resistance, which are considered evolutionary enigmas, are much more frequent. I discuss these results considering (i) the importance of different host defences at all stages of the breeding cycle, (ii) the role of phenotypic plasticity in long‐term coevolution, and (iii) the evolutionary history of host selection. I suggest that in purely antagonistic coevolutionary interactions, such as those involving brood parasites and their hosts, that although cycles will exist during an intermediate phase of the interactions, the arms race will end with the extinction of the host or with the host acquiring successful resistance. As evolutionary time passes, this resistance will force brood parasites to use previously less suitable host species. Furthermore, I present a model that represents the long‐term trajectories and outcomes of coevolutionary interactions between brood parasites and their hosts with respect to the evolution of egg‐rejection defence. This model suggests that as an increasing number of species acquire successful resistance, other unparasitized host species become more profitable and their parasitism rate and the costs imposed by brood parasitism at the population level will increase, selecting for the evolution of host defences. This means that although acceptance is adaptive when the parasitism rate and the costs of parasitism are very low, this cannot be considered to represent an evolutionary equilibrium, as conventional theory has done to date, because it is not stable.  相似文献   
85.

Background

A low birth weight has been extensively related to poor adult health outcomes. Birth weight can be seen as a proxy for environmental conditions during prenatal development. Identical twin pairs discordant for birth weight provide an extraordinary model for investigating the association between birth weight and adult life health while controlling for not only genetics but also postnatal rearing environment. We performed an epigenome-wide profiling on blood samples from 150 pairs of adult monozygotic twins discordant for birth weight to look for molecular evidence of epigenetic signatures in association with birth weight discordance.

Results

Our association analysis revealed no CpG site with genome-wide statistical significance (FDR < 0.05) for either qualitative (larger or smaller) or quantitative discordance in birth weight. Even with selected samples of extremely birth weight discordant twin pairs, no significant site was found except for 3 CpGs that displayed age-dependent intra-pair differential methylation with FDRs 0.014 (cg26856578, p = 3.42e-08), 0.0256 (cg15122603, p = 1.25e-07) and 0.0258 (cg16636641, p = 2.05e-07). Among the three sites, intra-pair differential methylation increased with age for cg26856578 but decreased with age for cg15122603 and cg16636641. There was no genome-wide statistical significance for sex-dependent effects on intra-pair differential methylation in either the whole samples or the extremely discordant twins.

Conclusions

Genome-wide DNA methylation profiling did not reveal epigenetic signatures of birth weight discordance although some sites displayed age-dependent intra-pair differential methylation in the extremely discordant twin pairs.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-1062) contains supplementary material, which is available to authorized users.  相似文献   
86.
Background: A significant factor influencing the prognosis of lung adenocarcinoma (LUAD) is tumor metastasis. Studies have shown that abnormal DNA methylation in circulating tumor cells (CTCs) is associated with tumour metastasis. Based on the genes expressed in CTCs that play an important role in DNA methylation, we hope to build a risk model to predict prognosis and provide a therapeutic strategy in LUAD.Methods: The CTC sequencing data for LUAD were obtained from GSE74639, which contains 10 CTC samples and 6 primary tumour samples. To carefully assess the clinical value, functional status, involvement of the tumor microenvironment (TME) based on the risk model, and genetic variants based on based on data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO), a reliable risk model was successfully built.Results: Three differentially methylated genes (DMGs) of CTCs for LUAD, including mitochondrial ribosomal protein L51 (MRPL51), STE20-like kinase (SLK), and protein regulator of cytokinesis 1(PRC1), were effectively used to construct a risk model. Both the training and validation cohorts'' stability and accuracy of the risk model were evaluated. Each patient in the TCGA-LUAD cohort received a risk score, and based on the median score, they were divided into high- and low-risk groups. The tumors in the high-risk group in this study were classified as "cold" and immunosuppressed, which may be linked to a poor prognosis. The tumors in the low-risk group, however, were deemed "hot" and had immune hyperfunction linked to a positive prognosis. Additionally, patients in the low-risk group showed greater sensitivity to immunotherapy than those in the high-risk group.Conclusions: Based on DMGs of CTCs from LUAD, we successfully developed a predictive risk model and discovered differences in biological function, TME, genetic variation, and clinical outcomes between those at high and low risk group.  相似文献   
87.
圈养獐分娩的初步观察   总被引:3,自引:0,他引:3  
2004年的5~7月,在浙江省嵊州市河麂种源繁育基地对34只獐(Hydropotes inermis)的分娩活动进行了观察。结果表明,母獐通常选择安全的地点进行分娩。獐集中分娩的时间为6月3日到6月19日,占分娩母獐总数的73.53%(n=34),并且分娩多在白天进行。产程(从胎膜露出到胎盘娩出)平均为(302.20±15.27)min(n=15)。胎儿娩出的姿势多为前躯前置(前足、头先露出),占83.78%;少数为后躯前置(后足先露出),占16.22%。幼仔首次吮乳时间在单胎和多胎间无显著差异,平均为出生后(44.97±2.73)min(n=35)。幼仔出生后首次平均站立时间在双胞胎、三胞胎和四胞胎分别为(32.25±2.49)min(n=16)(、29.42±2.52)min(n=12)和(65.00±7.39)min(n=6)。每胎幼仔数越多,初生幼仔的平均体重越轻。  相似文献   
88.
摘要 目的:探讨急诊危重孕产妇5分钟紧急剖宫产的临床效果,并分析新生儿不良结局的危险因素。方法:回顾性分析2018年1月~2022年6月在河北省儿童医院妇产科收治的急诊危重孕产妇139例的临床资料。根据急诊剖宫产流程分为对照组(n=68,常规紧急剖宫产流程下进行手术)及观察组(n=71,5分钟紧急剖宫产)。观察两组孕产妇的手术情况、手术反应时间、孕产妇并发症、新生儿不良结局发生率。采用多因素Logistic回归模型分析新生儿不良结局的危险因素。结果:两组住院时间、术中出血量、术中输血情况组间对比,未见统计学差异(P>0.05)。与对照组相比,观察组进手术室至手术开始时间、决定手术至胎儿娩出的时间间隔(DDI)、决定手术至进手术室时间、手术开始至胎儿娩出时间均更短,新生儿不良结局发生率、并发症发生率更低(P<0.05)。根据新生儿不良结局将孕产妇分为不良组(n=38)、良好组(n=101)。单因素分析结果显示:新生儿不良结局与受教育程度、新生儿体重、孕周、剖宫产类型、DDI、妊娠合并症、采用辅助生殖技术有关(P<0.05)。多因素Logistic回归分析结果显示,受教育程度为小学及其以下、新生儿体重偏低、剖宫产类型为I类剖宫产、孕周偏短、DDI偏长均是新生儿不良结局的危险因素(P<0.05)。结论:急诊危重孕产妇5分钟紧急剖宫产可缩短各项手术反应时间,降低孕产妇并发症和新生儿不良结局发生率。此外,新生儿不良结局的发生与受教育程度、新生儿体重、剖宫产类型、孕周、DDI等因素有关。  相似文献   
89.
Vitamin E is a naturally occurring fat-soluble antioxidant which has been proposed as a treatment for both primary and secondary protection against cardiovascular (CV) events. Promising data from observational epidemiological studies associating higher vitamin E dietary intake with lower risk of CV events have not been validated in randomized controlled clinical trials assessing the effect of vitamin E on CV outcomes. While the pendulum of medical opinion has swung to suggest that high dose vitamin E supplements have no place in the treatment and prevention of CV disease, new data is emerging that allows identification of a specific target population for this treatment, namely patients with diabetes mellitus and the haptoglobin genotype 2-2. This review details the scientific basis and clinical evidence related to the effect of vitamin E on CV outcomes, and the importance of proper patient selection in gaining therapeutic benefit from this intervention.  相似文献   
90.
Abstract It is already known that maternal overweight, obesity, and morbid obesity are associated with adverse obstetric and neonatal outcomes. To assess the prevalence of overweight and obesity, and the impact of body mass index (BMI) on maternal and neonatal outcomes in Turkey. The study population consisted of 698 singleton pregnancies whose height and weight follow up were performed from the first trimester of pregnancy and whose deliveries were monitored in Trabzon, Turkey in July 2014–June 2015. The data obtained during the study were evaluated using SPSS 21 package program. The differences in variables were assessed by Chi-square-test for categorical data or by One-way Anova test for continuous data. The results were evaluated at a confidence interval of 95% and at a significance level of p?<?0.05. According to the BMI of the women in the study, 68.8% were in normal weight, 20.6% were overweight, 3.9% were obese, and the majority was in the 20–29 age group and 8–15.9?kg. The rate of cesarean, instrumental delivery, induction, episiotomy, late breastfeeding, low apgar (<7 at 5?min), neonatal intensive care unit admission requirement, the newborn at 4000?g or more in overweight (BMI 25–29.9) and obese (BMI?≥?30) pregnancies was higher and the first and second phases of labor were longer (p?<?0.05). The study showed that as the pre-pregnancy body mass index and gestational weight gain increased the rates of cesarean section and interventional delivery increased and the neonatal need for neonatal intensive care unit increased.  相似文献   
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