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排序方式: 共有279条查询结果,搜索用时 15 毫秒
221.
Marine Geoffroy Marine Lemesle Alexandra Kleinclauss Sabine Mazerbourg Levy Batista Muriel Barberi-Heyob Thierry Bastogne Wilfrid Boireau Alain Rouleau Dorian Dupommier Michel Boisbrun Corinne Comoy Stphane Flament Isabelle Grillier-Vuissoz Sandra Kuntz 《International journal of molecular sciences》2022,23(12)
Breast cancer is one of the leading causes of cancer-related death among females worldwide. A major challenge is to develop innovative therapy in order to treat breast cancer subtypes resistant to current treatment. In the present study, we examined the effects of two Troglitazone derivatives Δ2-TGZ and AB186. Previous studies showed that both compounds induce apoptosis, nevertheless AB186 was a more potent agent. The kinetic of cellular events was investigated by real-time cell analysis system (RTCA) in MCF-7 (hormone dependent) and MDA-MB-231 (triple negative) breast cancer (TNBC) cells, followed by cell morphology analysis by immuno-localization. Both compounds induced a rapid modification of both impedance-based signals and cellular morphology. This process was associated with an inhibition of cell migration measured by wound healing and transwell assays in TNBC MDA-MB-231 and Hs578T cells. In order to identify cytoplasmic targets of AB186, we performed surface plasmon resonance (SPR) and pull-down analyses. Subsequently, 6 cytoskeleton components were identified as potential targets. We further validated α-tubulin as one of the direct targets of AB186. In conclusion, our results suggested that AB186 could be promising to develop novel therapeutic strategies to treat aggressive forms of breast cancer such as TNBC. 相似文献
222.
老年人保健饮料:混合发酵海带饮料的工艺研究 总被引:3,自引:0,他引:3
介绍以海带为主要原料,经乳酸菌发酵后,用科学方法调配制成特别适合老年人饮用的保健饮料的工艺过程,解决了海带饮料口味一直难以改善的问题 相似文献
223.
Alireza Shirpoor Syranush Minassian Siamak Salami Mohammad Hassan Khadem-Ansari Firouz Ghaderi-Pakdel Marine Yeghiazaryan 《Food chemistry》2009
It has been suggested that developmental alcohol-induced brain damage is mediated through increases in oxidative stress. Current research suggests that antioxidant therapy may afford some level of protection against the toxicity of alcohol and alcoholic beverage in cellular and genomic levels. Seven day pregnant wistar rats were randomly divided into three groups: control, ethanol and vitamin E treated alcoholic groups. Apoptosis, lipid peroxidation and protein oxidation amounts, as well as, catalase and superoxide dismutase (SOD) activities were compared in male offspring hippocampus and cerebellum in the end of lactation. Offspring from ethanol-exposed animals showed significant increase in apoptosis, protein carbonyl and lipid hydroperoxide (LPO) in hippocampus and cerebellum than controls. Vitamin E treatment significantly decreased apoptosis in ethanol group and restored the increased protein carbonyl and LPO contents and catalase activity to the level of controls. Our findings strongly support oxidative nature of alcohol-induced cellular stress in developing hippocampus and cerebellum, prove that oxidative stress induced cell apoptosis plays a crucial role in pathogenic consequences, and imply that a strong protective effect could be achieved using vitamin E as an antioxidant. 相似文献
224.
测井约束反演在埕岛油田储层预测中的应用 总被引:12,自引:1,他引:11
埕岛油田东部斜坡带下第三系油藏以三有洲、浊积房屋隐蔽岩性油气藏为主,是近年在该区发现的又一含油层系。该带储层埋藏深、厚度变化大,油气聚集成藏复杂。本文对利用测井约束反演技术进行储层预测方法进行了探讨,通过合成地震记录标定、子波提取和薄层识别等,结合本区特点,对储层进行追踪、预测,查清了该地区储层的分布规律,落实了有利的岩性圈闭,获得了较好的效果。 相似文献
225.
波动方程共炮检距道集叠前深度偏移 总被引:5,自引:1,他引:4
目前所用的几种波场外推算法(分步傅里叶、傅里叶有限差分、广义屏和频率--空间域有限差分)可以在共炮道集上获得较好的成像效果。在上述算法中,共炮道集为了兼顾各种波传播角,每炮偏移都要考虑相当多的边道,并且炮点和检波点要分别向下外推,因而计算量很大。针对上述问题,本文提出了基于双平方根算子的波动方程共炮检距道集的深度偏移方法,它适用于二维和三维叠前深度成像,其步骤为:①在高频假设条件下,把共炮检距道集波场延拓公式中的积分运算进行稳相近似,得到波场延拓的相移公式;②把速度场分裂为层内常速背景和变速扰动,可求得整个均匀层波场深度延拓的偏移时移量、各层的偏移时移量及振幅校正系数,进而可得到最终波场延拓值。脉冲响应测试和理论模型试算表明,该方法具有较高的计算效率和成像精度,可适用于复杂地质体成像。 相似文献
226.
XIONGYing YEJin-ming WANGDe-xun 《水动力学研究与进展(B辑)》2005,17(1):43-49
This paper has predicted the range and volume of unsteady sheet cavitation of a propeller by using the surface panel method. The linearization in cavity thickness is adopted to reduce the computing time and storage space. The iteration scheme between chordwise strips has been used because the range and volume of cavitation are both unknown. The propeller cavitation range determined by the calculation method presented in this paper agrees with the observation results of cavity image at cavitation tunnel very well, and this proves the practicability of the method. 相似文献
227.
Artem Mishukov Irina Odinokova Ekaterina Mndlyan Margarita Kobyakova Serazhutdin Abdullaev Vitaly Zhalimov Xenia Glukhova Vasiliy Galat Yekaterina Galat Anatoly Senotov Roman Fadeev Artem Artykov Marine E. Gasparian Marina Solovieva Igor Beletsky Ekhson Holmuhamedov 《International journal of molecular sciences》2022,23(24)
ONC201, the anticancer drug, targets and activates mitochondrial ATP-dependent caseinolytic peptidase P (ClpP), a serine protease located in the mitochondrial matrix. Given the promise of ONC201 in cancer treatment, we evaluated its effects on the breast ductal carcinoma cell line (BT474). We showed that the transient single-dose treatment of BT474 cells by 10 µM ONC201 for a period of less than 48 h induced a reversible growth arrest and a transient activation of an integrated stress response indicated by an increased expression of CHOP, ATF4, and GDF-15, and a reduced number of mtDNA nucleoids. A prolonged exposure to the drug (>48 h), however, initiated an irreversible loss of mtDNA, persistent activation of integrated stress response proteins, as well as cell cycle arrest, inhibition of proliferation, and suppression of the intrinsic apoptosis pathway. Since Natural Killer (NK) cells are quickly gaining momentum in cellular anti-cancer therapies, we evaluated the effect of ONC201 on the activity of the peripheral blood derived NK cells. We showed that following the ONC 201 exposure BT474 cells demonstrated enhanced sensitivity toward human NK cells that mediated killing. Together our data revealed that the effects of a single dose of ONC201 are dependent on the duration of exposure, specifically, while short-term exposure led to reversible changes; long-term exposure resulted in irreversible transformation of cells associated with the senescent phenotype. Our data further demonstrated that when used in combination with NK cells, ONC201 created a synergistic anti-cancer effect, thus suggesting its possible benefit in NK-cell based cellular immunotherapies for cancer treatment. 相似文献
228.
黄建国 《西北工业大学学报》1993,11(1):117-118
如何精确估计噪声中的正弦信号的频率是雷达、声纳、通信和生物医学工程等许多领域中的—个重要问题.对于高斯白噪声中的单个或能够很好分辨的P个正弦信号,其频率的极大似然估计就是周期图频率估计(PFE),也就是周期图功率谱最大的P个谱峰所对应的频率[1]. 在实际应用中,由于使用FFT等数字技术,对大量位于离散的谱线之间的频率均无法得到精确的频率估计.通常减小估计误差的方法有两种:一种是增加谱线的条数(M),但使计算量显著增加;另一种是利用抛物线内插法(PIFE),对谱峰的位置加以修正.这些方法减小误差的效果仍不明显,其频率估计的均方根误差(RMSE)如图1所示. 相似文献
229.
Natalia Voskoboynikova Philipp Orekhov Marine Bozdaganyan Felix Kodde Malte Rademacher Maurice Schowe Annette Budke-Gieseking Britta Brickwedde Olympia-Ekaterini Psathaki Armen Y. Mulkidjanian Katia Cosentino Konstantin V. Shaitan Heinz-Jürgen Steinhoff 《International journal of molecular sciences》2021,22(5)
Amphiphilic diisobutylene/maleic acid (DIBMA) copolymers extract lipid-encased membrane proteins from lipid bilayers in a detergent-free manner, yielding nanosized, discoidal DIBMA lipid particles (DIBMALPs). Depending on the DIBMA/lipid ratio, the size of DIBMALPs can be broadly varied which makes them suitable for the incorporation of proteins of different sizes. Here, we examine the influence of the DIBMALP sizes and the presence of protein on the dynamics of encased lipids. As shown by a set of biophysical methods, the stability of DIBMALPs remains unaffected at different DIBMA/lipid ratios. Coarse-grained molecular dynamics simulations confirm the formation of viable DIBMALPs with an overall size of up to 35 nm. Electron paramagnetic resonance spectroscopy of nitroxides located at the 5th, 12th or 16th carbon atom positions in phosphatidylcholine-based spin labels reveals that the dynamics of enclosed lipids are not altered by the DIBMALP size. The presence of the membrane protein sensory rhodopsin II from Natronomonas pharaonis (NpSRII) results in a slight increase in the lipid dynamics compared to empty DIBMALPs. The light-induced photocycle shows full functionality of DIBMALPs-embedded NpSRII and a significant effect of the protein-to-lipid ratio during preparation on the NpSRII dynamics. This study indicates a possible expansion of the applicability of the DIBMALP technology on studies of membrane protein–protein interaction and oligomerization in a constraining environment. 相似文献
230.
提出了一种正交网格的生成方法.通过调整边界点的位置而不是修正 ξ和η的值来达到正交的目的;通过调整 ξ和η的疏密从而达到控制网格疏密的目的.在内燃机冷却通道及水轮机尾水管上生成正交网格,得到满意的结果,从而证明该方法是可行的. 相似文献