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991.
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Fullerenes are of tremendous interest from fundamental researches to applied perspectives in the past decades. However, their application in supercapacitors has been underdeveloped for a long time. Here, the KOH activation of C70 microtubes is reported at high temperatures, which provides activated samples exhibiting excellent capacitive properties. The improved capacitive performance can be attributed to three aspects: the generation of macropores and micropores, the introduction of oxygen functionalities, and the formation of graphitic carbons from ellipsoidal fullerenes. The optimum activated state for supercapacitor application is achieved at 600 °C, at which the product exhibits the best electrochemical behavior with a gravimetric capacitance of 362.0 F g?1 at 0.1 A g?1 and excellent cycling stability with capacitance retention of 92.5% over 5000 cycles at 1 A g?1.  相似文献   
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995.
通过对猪细小病毒接毒时间TOI、MOI和收毒时间进行优化,开发了一种基于PK-15细胞静置培养的猪细小病毒生产工艺,最大病毒滴度达到107.5TCID50/ml。通过进一步优化接毒时间,成功建立了基于PK-15细胞反应器微载体悬浮培养的猪细小病毒培养工艺,在5L反应器上最大病毒滴度达到107.2TCID50/ml。首次发现乳酸对葡萄糖得率与病毒滴度的正相关性,当猪细小病毒滴度处于最大值时,乳酸对葡萄糖得率也达到最大值,可作为指针病毒滴度及收毒时间的重要参数。  相似文献   
996.
随着质谱技术的快速发展,蛋白质组学已成为继基因组学、转录组学之后的又一研究热点,寻找可靠的差异表达蛋白对于生物标记物的发现至关重要.因此,如何准确、灵敏地筛选出差异蛋白已成为基于质谱的定量蛋白质组学的主要研究内容之一.目前,针对该问题的研究方法众多,但这些方法策略的适用范围不尽相同.总体来说,基于质谱技术筛选差异蛋白的统计学策略可以分为3类:基于经典统计学派的策略、基于贝叶斯学派的统计检验策略和其他策略,这3类方法有各自的应用范围、特点及不足.此外,筛选过程还将产生部分假阳性结果,可以采用其他方法对差异表达蛋白的质量进行控制,以提高统计检验结果的可靠性.  相似文献   
997.
The roots of the perennial herb Gentiana macrophylla Pall. (GM) are known as Qinjiao, which has been used for centuries to treat systemic lupus erythematosus (SLE). However, little is known about the effects of GM on cholesterol-aggravated cardiac abnormalities in SLE, and the mechanisms thereof. This study investigates whether GM exhibits anti-apoptotic effects, focusing on the left ventricle (LV) of NZB/W F1 mice fed with high-cholesterol diet. The morphology and apoptotic status of ventricular tissues were determined by microscopy and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Levels of apoptotic biomarkers were determined by immunoblotting. The results thus obtained revealed that GM significantly reduced the cholesterol-aggravated apoptosis of LV in NZB/W F1 mice by suppressing both intrinsic and extrinsic apoptotic pathways. Additionally, GM significantly increased the cardiac insulin-like growth factors (IGF)-1 survival signaling and anti-apoptotic proteins in LV tissues. Accordingly, GM is considered to be beneficial in alleviating cholesterol-aggravated cardiac damage in SLE, and therefore constitute an alternative treatment for SLE patients with cardiac abnormalities.  相似文献   
998.
Perilipin 1 (Plin1) localizes at the surface of lipid droplets to regulate triglyceride storage and hydrolysis in adipocytes. Plin1 defect leads to low adiposity in mice and partial lipodystrophy in human. This study investigated the roles of Plin1 in adipocyte differentiation. Plin1 null (-/-) mice showed plenty of multilocular adipocytes and small unilocular adipocytes in adipose tissue, along with lack of a subpopulation of adipose progenitor cells capable of in vivo adipogenesis and along with downregulation of adipogenic pathway. Before initiation of differentiation, adipose stromal-vascular cells (SVCs) from Plin1-/- mice already accumulated numerous tiny lipid droplets, which increased in number and size during the first 12-h induction but thereafter became disappeared at day 1 of differentiation. The adipogenic signaling was dysregulated despite protein level of PPARγ was near normal in Plin1-/- SVCs like in Plin1-/- adipose tissue. Heterozygous Plin1+/- SVCs were able to develop lipid droplets, with both the number and size more than in Plin1-/- SVCs but less than in Plin1+/+ SVCs, indicating that Plin1 haploinsufficiency accounts for attenuated adipogenesis. Aberrant lipid droplet growth and differentiation of Plin1-/- SVCs were rescued by adenoviral Plin1 expression and were ameliorated by enhanced or prolonged adipogenic stimulation. Our finding suggests that Plin1 plays an important role in adipocyte differentiation and provides an insight into the pathology of partial lipodystrophy in patients with Plin1 mutation.  相似文献   
999.

Background

Calpain is activated following myocardial infarction and ablation of calpastatin (CAST), an endogenous inhibitor of calpains, promotes left ventricular remodeling after myocardial infarction (MI). The present study aimed to investigate the effect of transgenic over-expression of CAST on the post-infarction myocardial remodeling process.

Method

We established transgenic mice (TG) ubiquitously over-expressing human CAST protein and produced MI in TG mice and C57BL/6J wild-type (WT) littermates.

Results

The CAST protein expression was profoundly upregulated in the myocardial tissue of TG mice compared with WT littermates (P < 0.01). Overexpression of CAST significantly reduced the infarct size (P < 0.01) and blunted MI-induced interventricular hypertrophy, global myocardial fibrosis and collagen I and collagen III deposition, hypotension and hemodynamic disturbances at 21 days after MI. Moreover, the MI-induced up-regulation and activation of calpains were obviously attenuated in CAST TG mice. MI-induced down-regulation of CAST was partially reversed in TG mice. Additionally, the MI-caused imbalance of matrix metalloproteinases and their inhibitors was improved in TG mice.

Conclusions

Transgenic over-expression of CAST inhibits calpain activation and attenuates post-infarction myocardial remodeling.  相似文献   
1000.
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