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1.
为提高Western Blotting结果的可靠性,以蛋白溶出率和凝胶电泳蛋白条带完整性为指标,比较提取液种类、研磨方式、酶抑制剂种类及其体积分数和提取时间对南美白对虾肝胰腺蛋白提取效果的影响。采用优化后的提取方法获得高质量蛋白样品,并采用Western Blotting法分析无水环境胁迫后南美白对虾肝胰腺组织中细胞凋亡信号通路相关蛋白的表达水平。结果表明:RIPA裂解液作为提取溶剂所得的蛋白溶出率高于水提和磷酸盐缓冲液,电动匀浆和液氮研磨所得蛋白条带更完整,4%蛋白酶磷酸酶混合抑制剂能有效抑制肝胰腺内源酶引起的蛋白降解;采用Western Blotting法分析无水保活期间南美白对虾肝胰腺蛋白,发现低温诱导休眠的同时会引起细胞轻微凋亡,且凋亡水平呈应激时间依赖性增加,环境胁迫解除后有所回调。 相似文献
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Suk-Young Song Soonil Pyo Sungchul Choi Hee Sang Oh Jung Hwa Seo Ji Hea Yu Ahreum Baek Yoon-Kyum Shin Hoo Young Lee Ja Young Choi Sung-Rae Cho 《International journal of molecular sciences》2021,22(7)
Hypoxic–ischemic encephalopathy (HIE) is a devastating neonatal brain condition caused by lack of oxygen and limited blood flow. Environmental enrichment (EE) is a classic paradigm with a complex stimulation of physical, cognitive, and social components. EE can exert neuroplasticity and neuroprotective effects in immature brains. However, the exact mechanism of EE on the chronic condition of HIE remains unclear. HIE was induced by a permanent ligation of the right carotid artery, followed by an 8% O2 hypoxic condition for 1 h. At 6 weeks of age, HIE mice were randomly assigned to either standard cages or EE cages. In the behavioral assessments, EE mice showed significantly improved motor performances in rotarod tests, ladder walking tests, and hanging wire tests, compared with HIE control mice. EE mice also significantly enhanced cognitive performances in Y-maze tests. Particularly, EE mice showed a significant increase in Cav 2.1 (P/Q type) and presynaptic proteins by molecular assessments, and a significant increase of Cav 2.1 in histological assessments of the cerebral cortex and hippocampus. These results indicate that EE can upregulate the expression of the Cav 2.1 channel and presynaptic proteins related to the synaptic vesicle cycle and neurotransmitter release, which may be responsible for motor and cognitive improvements in HIE. 相似文献
3.
Zhiying Han Jinghe Bai Xu Chen Xiaofei Zhu Defeng Zhou 《International Journal of Hydrogen Energy》2021,46(21):11894-11907
The cobalt-free cathode materials with high activity is critical to the commercial application of medium temperature solid oxide fuel cells (IT-SOFC). Herein, a series of cobalt-free Nb-doped Pr2Ni1-xNbxO4 (x = 0, 0.05, 0.10, and 0.15) perovskite oxides were successfully prepared, and the effects of Nb-doping on the structure, thermal stability and electrochemical properties of the cathode material are studied in detail. The Pr2Ni1-xNbxO4 exhibits a K2NiF4 type structure with Fmmm space group. The Nb5+ cations that doped into Pr2NiO4 replaces the Ni site, which increases the surface oxygen content, then effectively eliminates the phase transition of Pr2NiO4 and significantly improves the ORR catalytic activity. The Pr2Ni0.9Nb0.1O4 was found to occupy the lowest polarization resistance of 0.057 Ω cm2, and the peak power density of single cells supported by the electrolyte is 0.576 W cm?2 at 700 °C, which has good long-term stability. 相似文献
4.
Food Science and Biotechnology - In this study, we aimed to determine the potential functional properties and biological activities of the hydrolysates of perilla seed meal (PSM), which is a... 相似文献
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Microsystem Technologies - Rotating components are one of the most important machine parts used in many industrial applications. Rotating machine commonly used in homes has a washing machine, which... 相似文献
6.
E. Ja. Kipko D. Sc. Min. Eng. 《Mine Water and the Environment》1985,4(2):35-39
The paper describes the results of an experimental grouting programme carried out by the Spetstamponazhgeologia association at the Dobrogea coalfield in Bulgaria. The anticipated water inflow into a shaft at this deposit totals 8 m3/s at a pressure of 12 MPa, from a cavity size equal or exceeding 3 metres. Grouting operations made it possible to cut down water inflow by a factor of more than one thousand. The success of this investigation has enabled the author to design an exprrimental shaft sinking project through the valange formation at Dobrogea mine. 相似文献
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Electrical properties and the role of inhomogeneities at the polyvinyl alcohol/n‐inp schottky barrier interface 下载免费PDF全文
M. Siva Pratap Reddy Hee‐Sung Kang Jung‐Hee Lee V. Rajagopal Reddy Ja‐Soon Jang 《应用聚合物科学杂志》2014,131(2)
In this work, we have investigated the electrical properties of Au/n‐InP contacts with a thin layer of polyvinyl alcohol (PVA) as an interlayer. The current–voltage (I–V) and capacitance–voltage (C–V) measurements are carried out in the temperature range of 175–425 K. The Au/PVA/n‐InP Schottky structure show nonideal behaviors and indicates the presence of a nonuniform distribution of interface states. The temperature dependent interface states densities (NSS), ideality factor and barrier height are obtained. An abnormal decrease in zero‐bias barrier height (BH) and increase in the ideality factor ( ) with decreasing temperature have been explained on the basis of the thermionic emission theory with Gaussian distribution (GD) of the BHs due to the BH inhomogeneities. The experimental I–V characteristics of Au/PVA/n‐InP Schottky diode has revealed the existence of a double GD with mean BH values of ( ) of 1.246 and 0.899 eV and standard deviation ( ) of 0.176 and 0.137 V, respectively. Consequently, the modified conventional activation energy versus plot gives and Richardson constants ( ) and the values are 1.17 and 0.71 eV and 9.9 and 6.9 A/cm2 K2, respectively, without using the temperature coefficient of the BH. The effective Richardson constant value of 9.9 A/cm2 K2 is very close to the theoretical value of 9.4 A/cm2 K2 for n‐InP. The discrepancy between Schottky barrier heights estimated from I–V and C–V measurements is also discussed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39773. 相似文献
10.
为研究水和岩样体积对砂岩物理力学及变形特性的影响,采用MTS815型岩石力学测试系统,对干燥和饱水状态下的3种不同体积(高径比2∶ 1)完整和裂隙砂岩进行单轴压缩试验。结果表明:完整和裂隙砂岩的孔隙率与饱和吸水率与岩样体积成正比;干燥和饱水的完整与裂隙砂岩单轴抗压强度均随体积增大而小幅降低;砂岩弹性模量和变形模量与岩样体积呈负相关,且水降低了砂岩的弹性模量与变形模量;干燥砂岩的泊松比随岩样体积增加而增大,而饱水砂岩则随岩样体积先增加,后稳定;干燥的完整和裂隙砂岩的宏观破坏形式由小尺寸的轴向多劈裂面破坏逐渐转变为大尺寸的单一剪切破坏,水的存在对岩样单轴压缩破坏形态没有明显影响。 相似文献