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91.
目的 探讨急性脑梗死(Acute cerebral infarction,ACI)患者血清微小RNA-497(MicroRNA-497,miR-497)、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)的表达水平变化及其临床意义。方法 选取2016年1月-2019年11月本院收治的96例ACI患者,称ACI组,并选取本院同期98例体检健康者,称对照组; 采用实时荧光定量PCR(Real-time fluorescent quantitative PCR,qRT-PCR)法检测所有研究对象血清miR-497表达水平; 采用酶联免疫吸附法(Enzyme-linked immunosorbent assay,ELISA)检测所有研究对象血清肿瘤坏死因子-α水平; 评估ACI患者神经功能缺损程度、计算脑梗死体积,比较不同神经功能缺损程度/脑梗死体积的ACI患者血清miR-497、TNF-α水平; Pearson法分析ACI患者血清miR-497、TNF-α水平与神经功能缺损程度评分(National institutes of health stroke scale,NIHSS)、脑梗死体积的关系; 采用受试者工作特征曲线(Receiver operating characteristic curve,ROC)评价血清miR-497、TNF-α对ACI的诊断价值。结果 ACI组血清miR-497、TNF-α水平均明显高于对照组(P<0.05); ACI患者血清miR-497、TNF-α水平随神经功能缺损程度加重、脑梗死体积增加均呈递增趋势(P均<0.05); ACI患者血清miR-497、TNF-α水平与脑梗死体积、NIHSS评分均呈正相关(r=0.423,0.514,0.542,0.399,P均<0.05); 血清miR-497、TNF-α对ACI诊断的曲线下面积(Area under curve,AUC)为0.848、0.806,截断值分别为1.29、1.27,相应灵敏度分别为82.3%、81.3%,特异度分别为76.5%、77.6%; 两者联合诊断ACI的AUC为0.907,其灵敏度、特异度分别为81.3%、90.8%。结论 miR-497、TNF-α在ACI患者血清中表达均上调,且与神经功能缺损程度、脑梗死体积有关,均可能在ACI进展中起一定作用,两者联合可有效提高ACI的诊断效能,有助于诊断、评估ACI患者的病情。  相似文献   
92.
The purpose of this study is to investigate the correlation between single-nucleotide polymorphism (SNP) at the 3' end of the untranslated region (UTR) of Sirtuin 2 (SIRT2) gene and the risk of developing Alzheimer’s disease (AD), and to explore its underlying mechanisms. In total, 260 patients with AD and 260 healthy controls were recruited in this study. The genotype of rs2015 and rs2241703 loci of the SIRT2 gene was analyzed by Sanger sequencing for all participants. Quantitative real-time Polymerase chain reaction (qRT-PCR) was used to analyze microRNAs (miRNAs) and SIRT2 mRNA levels. Western blotting was used to analyze the expression level of SIRT2 protein. The dual luciferase reporter gene assay and cell transfection were performed to examine the role of miRNAs in regulating SIRT2 expression. Carriers of the SIRT2 gene rs2015 locus A allele were 0.69 times less likely to develop AD than the carriers of the C allele (95% confidence interval (CI): 0.59–0.80, p < 0.01). The carriers of the SIRT2 gene rs2241703 locus A allele were 1.43 times more likely to develop AD than the carriers of the G allele (95% CI: 1.23–1.61, p < 0.01). The rs2015 locus single-nucleotide polymorphism (SNP) affected the binding efficiency between miR-376a-5p and miR-8061 and the 3'UTR of the SIRT2 gene, and miR-376a-5p and miR-8061 bound to SIRT2 rs2015 A allele to down-regulate the expression of the SIRT2 protein. The rs2241703 SNP affected the binding efficiency between miR-486-3p and the 3'UTR of SIRT2 gene, and miR-486-3p bound to SIRT2 rs2241703 A allele to down-regulate SIRT2 protein expression. The SIRT2 gene rs2015 and rs2241703 loci SNPs are associated with the risk of AD. The rs2015 locus SNP affects regulation of miR-376a-5p and miR-8061 in SIRT2 expression and the rs2241703 locus SNP affects regulation of miR-486-3p in SIRT2, but further studies are needed to verify this mechanism.  相似文献   
93.
本文报告1例鸟氨酸氨甲酰基转移酶缺乏症患者3次妊娠,最终在多学科管理下分娩一健康新生儿的诊疗经过。2013年患者首次妊娠,孕28周出现急性高氨血症收入上海交通大学医学院附属新华医院,诊断为鸟氨酸氨甲酰基转移酶缺乏症。给予低蛋白饮食及降血氨治疗,并在多学科管理下于孕32周剖宫产一男婴,但该男婴生后第3天死亡。基因分析提示患者及其新生儿鸟氨酸氨甲酰基转移酶基因均存在c.583G>A(G195R)突变。2015年患者再次自然妊娠,但产前诊断提示胎儿为男性,且鸟氨酸氨甲酰基转移酶基因存在同一位点纯合突变,于孕21周引产终止妊娠。2017年借助体外受精-胚胎移植及植入前基因诊断技术第3次妊娠,并在多学科管理下最终顺利分娩一名健康男婴。  相似文献   
94.
目的:对美国FDA紫皮书制度进行研究,结合我国生物制品监管现状与发展,探讨构建我国"生物制品已上市产品目录集"的必要性和可行性。方法:文献研究和对比研究法。结果:对美国紫皮书的内容和作用、美国紫皮书的制度支持及其关键要素进行了研究,在此基础上分析我国"生物制品已上市产品目录集"构建的必要性和可行性。结论:我国现阶段构建"生物制品已上市产品目录集"已具备一定的实施基础,具有可行性和必要性。  相似文献   
95.
Free fatty acid 1 (FFA1/GPR40) has attracted extensive attention as a novel target for the treatment of type 2 diabetes for its role in the enhancement of insulin secretion with glucose dependency. Aiming to develop novel potent FFA1 agonists, a new series of phenylpropionic acid derivatives were designed and synthesized on the basis of the modification of chemical cement of TAK‐875, AMG‐837, and LY2881835. Among them, most promising compounds 7 , 14 , and 15 were obtained with EC50 values of 82, 79, and 88 nM, exhibiting a powerful agonistic activity compared to TAK‐875 (95.1 nM). During Oral glucose tolerance test in normal mice, compound 7 , 14 , and 15 had significant glucose‐lowering effect at the dose of 50 mg/kg. Furthermore, compound 15 (50 mg/kg) also significantly improved in glucose tolerance in type 2 diabetic mice. Herein, we reported the discovery and optimization of a series of potent FFA1 agonists. The discovery supported further exploration surrounding this scaffold.  相似文献   
96.
微小RNA(miRNA)是一类高度保守的内源性小分子RNA。miRNA主要通过选择性结合mRNA调控基因表达。目前研究结果表明,中枢神经系统存在大量miRNA,并参与神经细胞的正常生长、发育,以及组织损伤修复、肿瘤发生、神经退行性变等多种病理、生理过程。笔者拟就新生儿缺血缺氧性脑病(HIE) miRNA谱系的最新研究进展进行阐述,探讨其miRNA特异性表达,对新生儿HIE诊断和预后判断的意义,旨在为该病的相关诊治研究提供参考。  相似文献   
97.
98.
Prior research has indicated that narratives are more persuasive than nonnarrative messages. One of the reasons for this effectiveness is that the narratives’ intention to persuade is often not explicit, thus making them less likely to be disputed. The goal of this research is to examine the moderating role of persuasive intent in narrative persuasion. To do so, we conducted a 2 (Message format: narrative vs. nonnarrative messages) × 2 (Persuasive intent: intent vs. no intent) experiment with a factorial design among 205 participants on the effects of health narrative messages. Results indicated that persuasive intent undermined the effects of health narratives on persuasion by reducing believability and increasing reactance. Both believability and reactance partially mediated the effects of the narrative messages on attitudes and behavioral intention.  相似文献   
99.
Fei  Xiaoyan  Shen  Lu  Ying  Shihui  Cai  Yehua  Zhang  Qi  Kong  Wentao  Zhou  Weijun  Shi  Jun 《Cognitive computation》2020,12(6):1252-1264

Elastography ultrasound (EUS) imaging has shown its effectiveness for diagnosis of tumors by providing additional information about tissue stiffness to the conventional B-mode ultrasound (BUS). However, due to the lack of EUS devices and experienced sonologists, EUS is not widely used, especially in rural areas. It is still a challenging task to improve the performance of the single-modal BUS-based computer-aided diagnosis (CAD) for tumors. In this work, we propose a novel transfer learning (TL)–based deep neural network (DNN) algorithm, named CW-PM-DNN, for the BUS-based CAD by transferring diagnosis knowledge from EUS during model training. CW-PM-DNN integrates both the feature-level and classifier-level knowledge transfer into a unified framework. In the feature-level TL, a bichannel DNN is learned by the cross-weight-based multimodal DL (MDL-CW) algorithm to transfer informative features from EUS to BUS. In the classifier-level TL, a projective model (PM)–based classifier is then embedded to the pretrained bichannel DNN to implement the parameter transfer in the classifier model at the second stage. The back-propagation procedure is then applied to optimize the whole CW-PM-DNN to further improve its performance. Experimental results on two bimodal ultrasound tumor datasets demonstrate that the proposed CW-PM-DNN achieves the best classification accuracy, sensitivity, and specificity of 89.02 ± 1.54%, 88.37 ± 4.72%, and 89.63 ± 4.06%, respectively, for the breast ultrasound dataset, and the corresponding values of 80.57 ± 3.41%, 76.67 ± 3.85%, and 83.94 ± 3.95%, respectively, for the prostate ultrasound dataset. The proposed two-stage TL-based CW-PM-DNN algorithm outperforms all the compared algorithms. It is also proved that the performance of the BUS-based CAD can be significantly improved by transferring the knowledge of EUS. It suggests that CW-PM-DNN has the potential for more applications in the field of medical image–based CAD.

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100.
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