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961.
microRNAs是一种小分子非编码RNA,广泛参与细胞的生长发育、分化和凋亡等生物学过程. microRNA-21(miR-21)是一个在实体肿瘤中高表达的miRNA,可促进癌细胞增殖. 为了研究miR-21在金华猪生长过程中的作用,本试验选取了金华猪80日龄胚胎的心、肝、脾、肺、肾、小肠、胰脏、皮脂组织,进行miR-21组织表达谱研究,结果发现miR-21在肝脏中的表达最高. 进一步以肝脏为对象,研究miR-21在金华猪不同生长阶段中的表达,结果显示胚胎80日龄的miR-21表达量最高(P<0.01),其次是胚胎期的60日龄和105日龄,出生后1至120日龄miR-21的表达量均维持在较低的水平且相互之间差异不显著(P>0.05). 利用KEGG软件对miR-21预测的靶基因进行通路归类分析表明miR-21参与细胞代谢、生长等过程,从中选择两个抑制细胞增殖的靶基因,增强子结合蛋白(CCAAT/enhancer binding protein,Cebpa) 和原肌球蛋白1基因(tropomyosin 1,Tpm1),qRT-PCR检测二者在不同生长阶段的mRNA表达量,结果其表达趋势与miR-21相反,其中胚胎期80天表达量最低(P<0.05). 综上表明miR-21可能具有促进胚胎肝脏生长的作用.  相似文献   
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Epigenetic mechanisms have important roles in carcinogenesis. We certified that the mRNA translation-related gene cytoplasmic polyadenylation element-binding protein 1 (CPEB1) is hypomethylated and overexpressed in glioma cells and tissues. The knockdown of CPEB1 reduced cell senescence by regulating the expression or distribution of p53 in glioma cells. CPEB1 is also regulated directly by the tumor suppressor miR-101, a potential marker of glioma. It is known that the histone methyltransferase enhancer of zeste homolog 2 (EZH2) and embryonic ectoderm development (EED) are direct targets of miR-101. We demonstrated that miR-101 downregulated the expression of CPEB1 through reversing the methylation status of the CPEB1 promoter by regulating the presence on the promoter of the methylation-related histones H3K4me2, H3K27me3, H3K9me3 and H4K20me3. The epigenetic regulation of H3K27me3 on CPEB1 promoter is mediated by EZH2 and EED. EZH2 has a role in the regulation of H3K4me2. Furthermore, the downregulation of CPEB1 induced senescence in a p53-dependent manner.  相似文献   
963.
Hexamer peptide ligand HWRGWV, initially screened from a solid phase combinatorial peptide library for immunoglobulins G (IgG) purification, is shown to also have potential for immunoglobulin A (IgA) purification. The determined dissociation constants for hIgA on HWRGWV resins at three different peptide densities from 0.11 to 0.55 meq/g fall in the range of 10?6–10?7 M, which are somewhat lower than those for hIgG. Although relatively low dynamic binding capacity (DBC) in the range of 9.2–16.8 mg IgA/mL resin at linear flow rates from 173 to 35 cm/h were obtained for IgA compared to IgG, the DBC value of HWRGWV for IgA is much greater than current commercially available affinity ligands. Although relatively lower binding affinity to secretory IgA compared to monomeric IgA was observed, the peptide ligand resins exhibit great potential for large‐scale purification of both human IgA and secretory IgA. Recoveries of 96.0% and 94.3%, and purities of 90.3% and 91.7% were achieved for human IgA and secretory IgA purification, respectively, from spiked Chinese hamster ovary cell culture supernatants without an extra afterwash step. Over 95% in purities were achieved for IgA and secretory IgA with an extra afterwash step; however, the recoveries would decrease at least 15% and 40% for IgA and secretory IgA, respectively. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013  相似文献   
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Background

Audit and feedback to physicians is a commonly used quality improvement strategy, but its optimal design is unknown. This trial tested the effects of a theory-informed worksheet to facilitate goal setting and action planning, appended to feedback reports on chronic disease management, compared to feedback reports provided without these worksheets.

Methods

A two-arm pragmatic cluster randomized trial was conducted, with allocation at the level of primary care clinics. Participants were family physicians who contributed data from their electronic medical records. The ‘usual feedback’ arm received feedback every six months for two years regarding the proportion of their patients meeting quality targets for diabetes and/or ischemic heart disease. The intervention arm received these same reports plus a worksheet designed to facilitate goal setting and action plan development in response to the feedback reports. Blood pressure (BP) and low-density lipoprotein cholesterol (LDL) values were compared after two years as the primary outcomes. Process outcomes measured the proportion of guideline-recommended actions (e.g., testing and prescribing) conducted within the appropriate timeframe. Intention-to-treat analysis was performed.

Results

Outcomes were similar across groups at baseline. Final analysis included 20 physicians from seven clinics and 1,832 patients in the intervention arm (15% loss to follow up) and 29 physicians from seven clinics and 2,223 patients in the usual feedback arm (10% loss to follow up). Ten of 20 physicians completed the worksheet at least once during the study. Mean BP was 128/72 in the feedback plus worksheet arm and 128/73 in the feedback alone arm, while LDL was 2.1 and 2.0, respectively. Thus, no significant differences were observed across groups in the primary outcomes, but mean haemoglobin A1c was lower in the feedback plus worksheet arm (7.2% versus 7.4%, p<0.001). Improvements in both arms were noted over time for one-half of the process outcomes.

Discussion

Appending a theory-informed goal setting and action planning worksheet to an externally produced audit and feedback intervention did not lead to improvements in patient outcomes. The results may be explained in part by passive dissemination of the worksheet leading to inadequate engagement with the intervention.

Trial registration

ClinicalTrials.gov NCT00996645
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