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Lilium fargesii Franchet is an endangered species endemic to China. In this study, the complete chloroplast genome has been generated from the Next Generation Sequencing. The whole genome is 153,235 bp in length, and includes one large single copy region of 82,217 bp, one small single copy region of 17,038 bp and a pair of inverted repeat region of 26,990 bp. It contains 132 genes, comprising 86 protein-coding genes (78 PCG species), 38 transfer RNA (30 tRNA species) and eight ribosomal RNA genes (four rRNA species). In the maximum likelihood tree, all species of Lilium were clustered into two monophyletic groups with 100 % bootstrap value.  相似文献   
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Recently, a single nucleotide polymorphism (SNP) in the CAMKK2 gene (rs1063843) was found to be associated with lower expression of the gene in the dorsolateral prefrontal cortex (DLPFC) and with schizophrenia (SCZ) and deficits in working memory and executive function. However, the brain mechanism underlying this association is poorly understood. A functional magnetic resonance imaging (fMRI) study (N = 84 healthy volunteers) involving multiple cognitive tasks, including a Stroop task (to measure attentional executive control), an N‐back task (to measure working memory), and a delay discounting task (to measure decision making) to identify the brain regions affected by rs1063843 was performed. Across all three tasks, it was found that carriers of the risk allele consistently exhibited increased activation of the left DLPFC. In addition, the risk allele carriers also exhibited increased activation of the right DLPFC and the left cerebellum during the Stroop task and of the left caudate nucleus during the N‐back task. These findings helped to elucidate the role of CAMKK2 in cognitive functions and in the etiology of SCZ. Hum Brain Mapp 37:2398–2406, 2016. © 2016 Wiley Periodicals, Inc .  相似文献   
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Objective: To evaluate the effects of differentiated adipose-derived stem cells (dADSC) and chondroitinase ABC (ChABC)-treated acellular nerves (ACN) in building artificial nerves and repairing nerve defects. Methods: ADSC were isolated from the adipose tissue of Wistar rats, induced to differentiate into Schwann-like cells, and implanted into ChABC-treated ACN to repair a 15-mm sciatic nerve defect in Sprague–Dawley rats (the experimental group, group D). The control groups were an autologous nerve transplantation group (group E); ACN (group A), ChABC-treated ACN graft group (group B), and dADSC + ACN (group C). Twelve weeks after surgery, electromyography recordings, tricep surae muscle wet weight recovery rate, and axon counts were measured to evaluate the repair of peripheral nerve defects. Results: The nerve conduction velocity, compound muscle action potentials, tricep surae muscle wet weight recovery rate, and myelinated axon counts in the ChABC-ACN/dADSC group were significantly higher than in the other groups (P < 0.05), which were all lower than the autologous group (P < 0.05). Conclusions: The combination of ChABC-treated ACN and dADSC exhibited a synergistic effect in promoting nerve regeneration, and could be an alternative for effective tissue-engineered nerves.  相似文献   
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Independent component analysis (ICA) has been widely applied to identify intrinsic brain networks from fMRI data. Group ICA computes group‐level components from all data and subsequently estimates individual‐level components to recapture intersubject variability. However, the best approach to handle artifacts, which may vary widely among subjects, is not yet clear. In this work, we study and compare two ICA approaches for artifacts removal. One approach, recommended in recent work by the Human Connectome Project, first performs ICA on individual subject data to remove artifacts, and then applies a group ICA on the cleaned data from all subjects. We refer to this approach as Individual ICA based artifacts Removal Plus Group ICA (IRPG). A second proposed approach, called Group Information Guided ICA (GIG‐ICA), performs ICA on group data, then removes the group‐level artifact components, and finally performs subject‐specific ICAs using the group‐level non‐artifact components as spatial references. We used simulations to evaluate the two approaches with respect to the effects of data quality, data quantity, variable number of sources among subjects, and spatially unique artifacts. Resting‐state test–retest datasets were also employed to investigate the reliability of functional networks. Results from simulations demonstrate GIG‐ICA has greater performance compared with IRPG, even in the case when single‐subject artifacts removal is perfect and when individual subjects have spatially unique artifacts. Experiments using test–retest data suggest that GIG‐ICA provides more reliable functional networks. Based on high estimation accuracy, ease of implementation, and high reliability of functional networks, we find GIG‐ICA to be a promising approach. Hum Brain Mapp 37:1005–1025, 2016. © 2015 Wiley Periodicals, Inc .  相似文献   
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目的研究移植人羊膜间充质干细胞(hAMSCs)是否促进脊髓损伤大鼠神经功能恢复,探索其可能作用机制。 方法60只雌性SD大鼠按照随机数字表法分为磷酸盐缓冲液(PBS)治疗组(30只)和hAMSCs治疗组(30只)。脊髓损伤采用脊髓撞击损伤模型,hAMSCs或PBS立刻移植到离脊髓损伤中心2 mm的头尾两端。免疫荧光检测细胞分化,血管再生和轴突再生。酶联免疫吸附剂测定试剂盒检测脑源性神经营养因子(BDNF)和血管内皮生长因子(VEGF)含量,BBB运动功能评分检测行为学。 结果在脊髓损伤后14 d、21 d和28 d,hAMSCs治疗组BBB评分分别为(8.75±0.701)、(10.375±0.532)和(12.125±0.350),高于PBS组(6.0±0.463)、(7.25±0.412)和(9.125±0.440),差异具有统计学意义(P<0.05)。在第7天和第14天,hAMSCs治疗组BDNF表达水平分别为(75.138±4.367)pg/mg和(66.483±4.099)pg/mg,高于PBS组(43.901±3.607)pg/mg和(41.108±3.848)pg/mg,差异具有统计学意义(P<0.05)。在第7天,第14天和第28天,hAMSCs治疗组VEGF表达水平分别为(23.328±2.463)pg/mg,(22.301±2.223)pg/mg和(14.855±1.282)pg/mg,高于PBS组(9.978±1.572)pg/mg,(9.271±1.496)pg/mg和(7.113±1.123)pg/mg,差异具有统计学意义(P<0.05)。hAMSCs治疗组血管数目(17.5±2.102)高于PBS组(6.25±1.750),差异具有统计学意义(P<0.05)。hAMSCs治疗组小鼠抗5羟色胺阳性神经纤维面积(3486±203.643)和GAP43阳性神经纤维面积(4568.25±253.881)高于PBS组(2070.25±156.344)和(2455.725±314.475),差异具有统计学意义(P<0.05)。 结论移植hAMSCs能促进脊髓损伤大鼠神经功能恢复,其作用机制可能是通过增加神经营养因子表达,促进血管再生和轴突再生。因此hAMSCs移植是治疗脊髓损伤的理想方法。  相似文献   
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