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81.
Haiyang Geng Feng Wu Lingtao Kong Yanqing Tang Qian Zhou Miao Chang Yifang Zhou Xiaowei Jiang Songbai Li Fei Wang 《PloS one》2016,11(2)
Background
Evidence implicates abnormalities in prefrontal-hippocampus neural circuitry in major depressive disorder (MDD). This study investigates the potential disruptions in prefrontal-hippocampus structural and functional connectivity, as well as their relationship in first-episode medication-naïve adolescents with MDD in order to investigate the early stage of the illness without confounds of illness course and medication exposure.Methods
Diffusion tensor imaging and resting-state functional magnetic resonance imaging (rs-fMRI) data were acquired from 26 first-episode medication-naïve MDD adolescents and 31 healthy controls (HC). Fractional anisotropy (FA) values of the fornix and the prefrontal-hippocampus functional connectivity was compared between MDD and HC groups. The correlation between the FA value of fornix and the strength of the functional connectivity in the prefrontal cortex (PFC) region showing significant differences between the two groups was identified.Results
Compared with the HC group, adolescent MDD group had significant lower FA values in the fornix, as well as decreased functional connectivity in four PFC regions. Significant negative correlations were observed between fornix FA values and functional connectivity from hippocampus to PFC within the HC group. There was no significant correlation between the fornix FA and the strength of functional connectivity within the adolescent MDD group.Conclusions
First-episode medication-naïve adolescent MDD showed decreased structural and functional connectivity as well as deficits of the association between structural and functional connectivity shown in HC in the PFC-hippocampus neural circuitry. These findings suggest that abnormal PFC-hippocampus neural circuitry may present in the early onset of MDD and play an important role in the neuropathophysiology of MDD. 相似文献82.
BackgroundThe use of dexmedetomidine may have benefits on the clinical outcomes of cardiac surgery. We conducted a meta-analysis comparing the postoperative complications in patients undergoing cardiac surgery with dexmedetomidine versus other perioperative medications to determine the influence of perioperative dexmedetomidine on cardiac surgery patients.MethodsRandomized or quasi-randomized controlled trials comparing outcomes in patients who underwent cardiac surgery with dexmedetomidine, another medication, or a placebo were retrieved from EMBASE, PubMed, the Cochrane Library, and Science Citation Index.ResultsA total of 1702 patients in 14 studies met the selection criteria among 1,535 studies that fit the research strategy. Compared to other medications, dexmedetomidine has combined risk ratios of 0.28 (95% confidence interval [CI] 0.15, 0.55, P = 0.0002) for ventricular tachycardia, 0.35 (95% CI 0.20, 0.62, P = 0.0004) for postoperative delirium, 0.76 (95% CI 0.55, 1.06, P = 0.11) for atrial fibrillation, 1.08 (95% CI 0.74, 1.57, P = 0.69) for hypotension, and 2.23 (95% CI 1.36, 3.67, P = 0.001) for bradycardia. In addition, dexmedetomidine may reduce the length of intensive care unit (ICU) and hospital stay.ConclusionsThis meta-analysis revealed that the perioperative use of dexmedetomidine in patients undergoing cardiac surgery can reduce the risk of postoperative ventricular tachycardia and delirium, but may increase the risk of bradycardia. The estimates showed a decreased risk of atrial fibrillation, shorter length of ICU stay and hospitalization, and increased risk of hypotension with dexmedetomidine. 相似文献
83.
Anaerobic methane oxidation coupled to nitrite reduction can be a potential methane sink in coastal environments 总被引:1,自引:0,他引:1
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大学生素质教育要求新时代的大学生不仅要学习理论知识,更重要的是培养科学思维并掌握应用技能。我校微生物学课程教学中探索了以创新实践为主要内容的模式改革,其中"理论—技能—创新实践"同步训练的创新模式,是以将参与创新实践计入期末成绩的形式"强迫"学生进入实验室参与科研项目。实施中我们以"教师—研究生—创新小组"交互学习的方式,任课教师制定规则与目标,研究生帮助创新项目的选题、研究方案设计及实施指导,创新小组依照目标参与研究生的科研课题,最后完成创新实践并获得一定比例的成绩。实践证实创新实践教学对促进学生的理论课程学习、科学思维培养以及创新意识训练等方面都有积极的促进作用,是大学生素质教育的一种实用且高效的教学模式。 相似文献
86.
Geng Chen Juan Yang Jiwei Chen Yunjie Song Ruifang Cao Tieliu Shi Leming Shi 《中国科学:生命科学英文版》2016,59(10):981-992
Bifunctional RNAs that possess both protein-coding and noncoding functional properties were less explored and poorly understood. Here we systematically explored the characteristics and functions of such human bifunctional RNAs by integrating tandem mass spectrometry and RNA-seq data. We first constructed a pipeline to identify and annotate bifunctional RNAs, leading to the characterization of 132 high-confidence bifunctional RNAs. Our analyses indicate that bifunctional RNAs may be involved in human embryonic development and can be functional in diverse tissues. Moreover, bifunctional RNAs could interact with multiple miRNAs and RNA-binding proteins to exert their corresponding roles. Bifunctional RNAs may also function as competing endogenous RNAs to regulate the expression of many genes by competing for common targeting miRNAs. Finally, somatic mutations of diverse carcinomas may generate harmful effect on corresponding bifunctional RNAs. Collectively, our study not only provides the pipeline for identifying and annotating bifunctional RNAs but also reveals their important gene-regulatory functions. 相似文献
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89.
目的:探讨光纤成像技术用于记录小鼠眶额皮层奖赏相关神经元活性变化的可行性。方法:应用光纤成像的方法记录自由活动小鼠在饮用糖水时,携带有钙离子荧光探针(GCaMP6m)的眶额皮层奖赏相关神经元的活性。首先,在小鼠的眶额皮层注射携带GCaMP6m的腺相关病毒,同时在相应位点植入提前做好的光纤陶瓷插芯;等待小鼠术后恢复,病毒表达2周。然后在记录前,给予小鼠36小时禁水处理并运用光纤成像记录接受糖水刺激的小鼠眶额皮层锥体神经元的反应活性。最后,记录数据读入matlab软件进行数据分析并对小鼠进行心脏灌流、取脑、脑组织冰冻切片并显微荧光成像观察记录位点是否正确,病毒是否正常表达。结果:成功记录到对小鼠施加糖水刺激时,其眶额皮层内与奖赏相关的神经元活性变化。数据分析结果用热度图和事件相关的平均线图来表示。组织学切片及成像结果证实记录位点正确,病毒正常表达。结论:光纤成像的记录方法可以监测自由活动的小鼠在饮用糖水时眶额皮层内奖赏相关神经元活性的变化。 相似文献
90.
基于SSR分子标记技术,按树高和胸径(地径)因子将样地内的植株分为优势木、中等木和劣势木3类,对不同生长优势等级云南松林木的遗传多样性变异特征进行了研究。结果表明:在林冠层,优势木的有效等位基因数、Shannon's信息指数、观测杂合度和期望杂合度分别为2.083、0.762、0.290和0.423,略高于中等木和劣势木;在更新层,有效等位基因数、Shannon's信息指数、观测杂合度和期望杂合度分别为2.063、0.774、0.272和0.410,除观测杂合度外,其余3个指标也均表现为优势木略高于中等木和劣势木。从差异显著性检验来看,不同生长优势等级云南松林木间的遗传多样性差异不显著,即林木生长分化对遗传多样性的影响不明显。 相似文献