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目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。  相似文献   
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Drosophila suzukii is a significant pest of stone and small fruits. The genome of this species has been sequenced and manipulated by transposon‐mediated transformation and CRISPR/Cas9 gene editing. These technologies open a variety of possibilities for functional genomics and genetic modifications that might improve biologically based population control strategies. Both of these approaches, however, would benefit from genome targeting that would avoid position effects and insertional mutations associated with random transposon vector insertions, and the limited DNA fragment insertion size allowed by gene editing. Here, we describe an efficient recombinase‐mediated cassette exchange (RMCE) system for D. suzukii in which heterospecific lox recombination sites were integrated into the genome by transposon‐mediated transformation and subsequently targeted for double recombination by a donor vector in the presence of Cre recombinase. Three loxN/lox2272 landing site lines have previously been created in D. suzukii, and quantitative PCR determined that polyubiquitin‐regulated enhanced green fluorescent protein expression is least susceptible to position effect suppression in the 443_M26m1 line. We presume that RMCE target sites may also be inserted more specifically into the genome by homology‐directed repair gene editing, thereby avoiding position effects and mutations, while eliminating restrictions on the size of donor constructs for subsequent insertion.  相似文献   
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ObjectiveDiabetic women have different reproductive problems. In pregnant diabetic women, high rates of perinatal mortality, spontaneous abortion and congenital anomalies are observed. We hypothesized that quercetin, as an antidiabetic and phytoestrogen, might have protective effects on the embryo implantation in pregnant diabetic mice. We investigated the ameliorative effects of quercetin on the levels of serum estrogen and progesterone, rate of blastocyst implantation, and uterine receptivity markers in diabetic mice.Materials and methodsDiabetic and healthy female mice were treated with quercetin (30 mg/kg/day) four weeks before pregnancy. Plasma sex-steroid levels were determined on day 4 of pregnancy. Also, uteri were harvested for investigation of protein and mRNA expression changes. In another set of our study, implantation rate was determined on day 5 of pregnancy.ResultsOur results indicated that quercetin was significantly reduced blood glucose levels in diabetic mice. The number of implantation sites as well as serum estradiol level was reduced in diabetic mice, and then treatment with quercetin significantly increased both. On the other hand, insulin like growth factor1, integrin αvβ3, and cyclooxygenase2 mRNA expression in the uterus of diabetic mice were significantly reduced, and quercetin treatment augmented the expression level of these genes. Besides, the level of inactive β-catenin protein level in the uterus of diabetic mice was higher than normal group; treatment with quercetin reduced the level of inactive β-catenin protein as compared to diabetic mice.ConclusionWe conclude that administration of quercetin before pregnancy can probably alleviate reproductive problems in diabetic women likely via its estrogenic and antihyperglycemic effects.  相似文献   
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BackgroundConducting high-quality stroke trials is complex and costly. Often these trials compete for the attention of researchers and the availability of patients. Enrolling patients in more than one study concurrently has the potential to accelerate recruitment into individual studies. DISCOVERY is a multicenter, inception cohort study of cognitive impairment and dementia following ischemic or hemorrhagic stroke. At the request of site investigators, a DISCOVERY committee reviews individual studies for approval of possible concurrent co-enrollment into DISCOVERY. The purpose of this report is to summarize the characteristics and outcomes of studies reviewed by committee for possible co-enrollment.MethodsThis analysis covers studies reviewed from 07/01/2020 to 04/26/2022 by the Site Management Committee (SMC) of the DISCOVERY Recruitment and Retention Core. Characterization of each study included study type, number and length of follow-up visits, and whether there were protocol-required blood draws, brain imaging studies, or cognitive tests. Studies were scored for patient burden and scientific overlap with Discovery. The primary outcome was SMC approval to co-enroll.Results59 studies were reviewed, and 69.5% (n = 41, 21 clinical trials; 20 observational studies) were found by the SMC to be appropriate for co-enrollment. Higher patient burden and greater scientific overlap with DISCOVERY reduced the rates of approval for co-enrollment.ConclusionA large number of diverse stroke studies are being run concurrently across the DISCOVERY study network, however, about two-thirds of the studies were considered appropriate for consideration of co-enrollment. Future studies should study how co-enrollment might improve trial network efficiency.  相似文献   
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目的 :在中国汉族人群中验证易感基因CELSR2与青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)发病的相关性。方法:利用等位基因特异性多重连接酶检测反应在1794例AIS患者和1040例正常对照人群中对既往报道的CELSR2基因的易感位点rs141489111、rs6698843和rs2281894进行基因分型。同时在本中心全基因组数据库中分析CELSR2基因其他单核苷酸多态性位点(SNP)的基因分型信息。术中收集45例AIS患者(AIS组)和10例年龄匹配的脊柱外伤患者(对照组)的椎旁肌,比较两组椎旁肌中基因表达水平的差异。利用卡方检验分析组间SNP位点最小等位基因频率差异,采用T检验对组间的基因表达水平进行统计分析。结果:1794例AIS患者和1040例正常对照人群中,rs141489111位点未检测到突变,所有研究对象基因型均为GG。SNP位点rs6698843和rs2281894的基因型及等位基因频率在AIS和正常对照人群间未见显著性差异(P0.05)。GWAS数据库显示其他7个位于CELSR2基因上的SNP位点与AIS亦无显著相关性(P0.05)。CELSR2基因在AIS组和对照组椎旁肌的表达水平无显著性差异(P0.05)。结论:既往报道的易感基因CELSR2上的突变位点和多态性位点均未在中国汉族人群中得到验证,AIS患者椎旁肌组织中CELSR2表达未见明显异常。CELSR2可能与汉族AIS的发生无关。  相似文献   
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