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991.
本文通过观察实验性颞下颌关节炎症是否影响大鼠三叉神经节钠离子通道1.8(Nav1.8)mRNA的表达及其在雌、雄大鼠的表达有否差异,探讨钠离子通道是否参与调控颞下颌关节炎性痛及其性别差异。通过注射完全弗氏佐剂于SD大鼠颞下颌关节上腔建立颞下颌关节炎症模型,采用组织病理学手段确认关节炎症;通过测量摆头阈值及2小时进食量评估大鼠疼痛行为学的改变,采用实时荧光定量PCR方法评估三叉神经节Nav1.8 mRNA变化。结果显示,诱导颞下颌关节炎症24小时后,滑膜组织出现增生、炎细胞浸润及血管增生等滑膜炎特征;摆头阈值及2小时进食量明显降低,且雌性摆头阈值及2小时进食量低于雄性;同时三叉神经节Nav1.8 mRNA出现上调,且雌性Nav1.8 mRNA上调幅度高于雄性。这些结果提示,三叉神经节Nav1.8可能参与调控颞下颌关节炎性痛以及其性别差异,为进一步理解颞下颌关节紊乱病相关疼痛及其性别差异提供实验依据。 相似文献
992.
利用高速纹影法进行了天然气/柴油双燃料发动机同轴喷射试验,分析了不同天然气喷射压力和环境压力对天然气喷射的3种轮廓线周长变化的影响.采用CFD软件进行了数值模拟,利用ENSIGHT软件对双燃料发动机同轴喷射进行了天然气体积分数和速度场分析.结果表明:随着天然气喷射压力的下降和环境背压升高,天然气射流的3种轮廓线周长均减... 相似文献
993.
大学英语教育改革虽然已经历了多年,而高校英语课堂真正达到令人满意的程度并不多。本文通过对高校英语教学现状与英语学习主体作用的浅析,呼吁高校英语教学应重视加强学生自主学习能力的培养。大学英语多维一体主题教学自主学习模式(简称ITILA模式)将有意义的课堂教学与学生自主学习融为一体,笔者以为,是高校值得借鉴和推广的教学模式之一。 相似文献
994.
介绍了超高速碰撞过程中等离子体产生的环形电磁场测量方法,测量过程中采用螺旋型线圈,并分析了该线圈对外界干扰磁场的屏蔽效应.实验中采用该线圈测量到速度为6.2km/s的球形LY12铝弹丸超高速碰撞LY12铝靶板产生磁场强度随时间的变化规律.测试结果表明,等离子体产生的瞬态电磁场的持续时间为1ms左右,最大幅值为15μT. 相似文献
995.
Mapping of low or single-copy sequences on plant chromosomes has proven difficult because of very low frequency of signal
detection. Rice BAC library is being used widely in rice genome research due to its distinctive advantages over other library
systems. In this study, two biotin-labeled rice BAC clones closely linked to a rice blast resistance, green leafhopper resistance
and tungro spherical virus resistance gene,Pi-5(t), Glh, RTSV, werein situ hybridized to rice chromosomes. They were located on the long arm and short arm of chromosome 4 with FL value of 40% and
100% respectively. The frequency of signal detection reached 46.8% and 59.2%. The signal location were consistent with the
selective marker on rice saturated molecular map. The results demonstrated the advantages to locate BAC clones to chromosomes
byin situ hybridization and will facilitate the rice low or single-copy gene location by using the BAC library.
Supported by the National Natural Science Foundation of China and the Doctorate Vesting Point Foundation of the Education
Department of the People's Republic of China
Yan Huimin: born in 1964, Lecturer 相似文献
996.
In this paper, a four-dimensional (4D) continuous autonomous hyperchaotic system is introduced and analyzed. This hyperchaotic system is constructed by adding a linear controller to the 3D autonomous chaotic system with a reverse butterfly-shape attractor. Some of its basic dynamical properties, such as Lyapunov exponents, Poincare section, bifurcation diagram and the periodic orbits evolving into chaotic, hyperchaotic dynamical behavior by varying parameter d are studied. Furthermore, the full state hybrid projective synchronization (FSHPS) of new hyperchaotic system with unknown parameters including the unknown coefficients of nonlinear terms is studied by using adaptive control. Numerical simulations are presented to show the effective of the proposed chaos synchronization scheme. 相似文献
997.
According to the color constancy theory, a modified variation Retinex is proposed for improving the visibility of the dark regions in images under insufficient and/or non-uniform lighting conditions. A new penalty functional based on nonlinear diffusion and correlation between the reflectance and the given image is designed for the intensity image enhancement, followed by adaptive color compensation. With high computational efficiency achieved by an improved multi-resolution algorithm, simulation results prove that the proposed method shows more colorful and vivid visual performance, and achieves wider dynamic range with higher objective standard values. 相似文献
998.
Pengbo Jiang Yongchen Shang Tiexin Cheng Yingli Bi Keying Shi Shuquan Wei Guolin Xu Kaiji ZhenCollege of Chemistry Jilin University Changchun China Department of Chemistry Harbin Normal University Harbin China 《天然气化学杂志》2003,12(3)
The decomposition of methane on Ni/a-Al2O3 modified by La2O3 and CeO2 with different contents has been investigated and the ralationship between methane decomposition and removal of carbon by CO2 over these catalyst has also been studied by pulse-chromatography. The catalysts were characterized by TPR and XRD. It was shown that Ni/a-Al2O3 could be promoted by adding La2O3, and the carbon species produced over this catalyst was activated and eliminated by CO2. But CeO2 would suppress the decomposition of methane over Ni crystallite. Both La2O3 and CeO2 can inhibit aggregation of the Ni particles. Decomposition of methane over the Ni-based catalysts is structure sensitive to a certain extent. 相似文献
999.
具有拟除虫菊酯活性的肟醚类化合物 总被引:1,自引:0,他引:1
本文报导一类具有拟除虫菊酯活性的肟醚类化合物的合成、结构特性及生物活性。其中某些化合物对粘虫等有很高杀虫活性而对温血动物急性毒性很低,有希望发展成一类新型杀虫剂。 相似文献
1000.
Huichang Bi Kristopher W. Krausz Soumen K. Manna Fei Li Caroline H. Johnson Frank J. Gonzalez 《Analytical and bioanalytical chemistry》2013,405(15):5279-5289
In this study, a liquid chromatography mass spectrometry (LC/MS)-based metabolomics protocol was optimized for quenching, harvesting, and extraction of metabolites from the human pancreatic cancer cell line Panc-1. Trypsin/ethylenediaminetetraacetic acid (EDTA) treatment and cell scraping in water were compared for sample harvesting. Four different extraction methods were compared to investigate the efficiency of intracellular metabolite extraction, including pure acetonitrile, methanol, methanol/chloroform/H2O, and methanol/chloroform/acetonitrile. The separation efficiencies of hydrophilic interaction chromatography (HILIC) and reversed-phase liquid chromatography (RPLC) with UPLC-QTOF-MS were also evaluated. Global metabolomics profiles were compared; the number of total detected features and the recovery and relative extraction efficiencies of target metabolites were assessed. Trypsin/EDTA treatment caused substantial metabolite leakage proving it inadequate for metabolomics studies. Direct scraping after flash quenching with liquid nitrogen was chosen to harvest Panc-1 cells which allowed for samples to be stored before extraction. Methanol/chloroform/H2O was chosen as the optimal extraction solvent to recover the highest number of intracellular features with the best reproducibility. HILIC had better resolution for intracellular metabolites of Panc-1 cells. This optimized method therefore provides high sensitivity and reproducibility for a variety of cellular metabolites and can be applicable to further LC/MS-based global metabolomics study on Panc-1 cell lines and possibly other cancer cell lines with similar chemical and physical properties. Figure
Optimized harvesting, extraction and analytical protocols for cell metabolomics analysis. 相似文献