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排序方式: 共有1311条查询结果,搜索用时 62 毫秒
81.
LncRNAs has been demonstrated to modulate neoplastic development by modulating downstream miRNAs and functional genes. In this study, we aimed to detect the interaction among lncRNA ZFAS1 miR‐296‐5p and USF1. We explored the proliferation, migration and invasion of cholangiocarcinoma. The differentially expressed ZFAS1 was discovered in both tissues and cell lines by qRT‐PCR. The targeting relationship between miR‐296‐5p and ZFAS1 or USF1 was validated by dual‐luciferase assay. The impact of ZFAS1 on CCA cell proliferation was observed by CCK‐8 assay. The protein expression of USF1 was determined by Western blot. The effects of ZFAS1, miR‐296‐5p and USF1 on tumour growth were further confirmed using xenograft model. LncRNA ZFAS1 expression was relatively up‐regulated in tumour tissues and cells while miR‐296‐5p was significantly down‐regulated. Knockdown of ZFAS1 significantly suppressed tumour proliferation, migration, invasion and USF1 expression. Overexpressed miR‐296‐5p suppressed cell proliferation and metastasis. Knockdown of USF1 inhibited cell proliferation and metastasis and xenograft tumour growth. In conclusion, ZFAS1 might promote cholangiocarcinoma proliferation and metastasis by modulating USF1 via miR‐296‐5p.  相似文献   
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83.
本研究旨在筛选调控北极狐毛色基因CBD103的启动子活性区域及转录因子结合位点,为揭示CBD103基因调控北极狐毛色形成的分子遗传机制提供依据。克隆获得了北极狐CBD103基因5′侧翼区2 123 bp的片段,并构建了4个不同长度的启动子缺失片段表达载体,通过双荧光素酶检测系统对启动子活性进行检测。对启动子活性最高区域预测出的3个特异性蛋白1 (Sp1)转录因子结合位点分别进行点突变并构建3个突变载体,利用双荧光素酶检测系统测定其活性。结果显示,在构建的4个不同长度启动子缺失片段中1 656 (-1 604/+51)区域活性最高,在此区域构建的3个突变载体的启动子活性较野生型(片段1 656)均显著降低,说明-1 604/+51区域为北极狐CBD103基因的核心启动子区,-1 552/-1 564、-1 439/-1 454和-329/-339区域为正调控区域。文中成功获得了北极狐CBD103基因的核心启动子区域和正调控区域,这为进一步研究该基因调控北极狐被毛颜色分子遗传机制奠定了基础。  相似文献   
84.
入侵植物与重金属胁迫的相互作用研究进展 全球变化改变了植物群落的分布格局,包括入侵植物,而人为污染可能降低本地植物对入侵植物的抗性。因此,本文总结了近几十年本地植物、入侵植物和植物-土壤生态系统中重金属生物地球化学行为的研究,以加深我们对入侵植物与环境胁迫因子相互作用的认识。我们的研究结合已有文献报道表明:(i)入侵物种对环境胁迫的影响具有异质性, (ii)影响的大小是多变的, (iii)即使在同一影响类型内,影响类型也具有多向性。然而,入侵植物暴露在重金属环境中表现出更强的自我保护机制,对重金属的生物可利用性和毒性有正向或负向的影响。另一方面,由于入侵植物普遍具有较高的耐受性,加之本地植物暴露于有毒重金属污染时具有“逃逸行为”,重金属胁迫环境更有利于植物的成功入侵。但是,对于入侵植物的重金属等元素组成是否与污染地区的本地植物不同,目前尚无共识。因此,在全球范围内对外来入侵植物与本土植物的植物体内、凋落物和土壤污染物含量进行定量比较是今后研究的一个重要方向。  相似文献   
85.
Apoptosis repressor with caspase recruitment domain (ARC), an anti-apoptotic protein, is highly expressed in differentiated heart and skeletal muscle. Apoptosis and differentiation share numerous common pathways; therefore, we examined the impact of ARC on H9c2-myoblast differentiation. We demonstrate that ARC expression levels increase and stabilize upon differentiation. ARC-overexpression in pre-differentiated H9c2-cells suppresses differentiation; indicated by increased myotube formation, nuclear fusion and expression of the differentiation markers myogenin and troponin-T. ARC-overexpression inhibited myoblast differentiation associated caspase-3 activation, suggesting ARC inhibits myogenic differentiation through caspase inhibition. In summary, we show a novel role for ARC in the regulation of muscle differentiation.  相似文献   
86.
Zheng J  Wei C  Leng W  Dong J  Li R  Li W  Wang J  Zhang Z  Jin Q 《Proteomics》2007,7(21):3919-3931
Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine has been known for a long time to prevent tuberculosis (TB) worldwide since 1921. Nonetheless, we know little about BCG membrane proteome. In the present study, we utilized alkaline incubation and Triton X-114-based methods to enrich BCG membrane proteins and subsequently digested them using proteolytic enzyme. The recovered peptides were further separated by 2-D LC and identified by ESI-MS/MS. As a result, total 474 proteins were identified, including 78 integral membrane proteins (IMPs). Notably, 18 BCG IMPs were described for the first time in mycobacterium. Further analysis of the 78 IMPs indicated that the theoretical molecular mass distribution of them ranged from 8.06 to 167.86 kDa and pI scores ranged from 4.40 to 11.60. Functional classification revealed that a large proportion of the identified IMPs (67.9%, 53 out of 78) were involved in cell wall and cell processes functional group. In conclusion, here we reported a comprehensive profile of the BCG membrane subproteome. The present investigation may allow the identification of some valuable vaccine and drug target candidates and thus provide basement for future designing of preventive, diagnostic, and therapeutic strategies against TB.  相似文献   
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88.
Biomechanics and Modeling in Mechanobiology - Subcutaneous injection of therapeutic monoclonal antibodies (mAbs) has gained increasing interest in the pharmaceutical industry. The transport,...  相似文献   
89.
2019-2020年,在黄河中游晋陕峡谷陕西一侧龙门至壶口段新发现9处旷野旧石器地点,采集石制品136件,部分石制品直接采自地层剖面上。康家岭地点石制品的埋藏地层为马兰黄土底部的洪积碎屑层,时代可能为晚更新世早期。苏家岭地点有1件石制品出自MIS3阶段弱古土壤层之下的洪积碎屑层,光释光年龄为距今7.2±0.7万年。其余大部分石制品的埋藏地层为马兰黄土层,时代为晚更新世中、晚期,其中凉泉沟地点埋藏石制品的黄土地层光释光年龄大于距今5万年。古人类加工石制品的原料主要为砾石,岩性以石英岩为主,其次为石英,此外还有少量燧石、细砂岩和硅质岩。石制品类型包括石核、石片、石器和断块。个体大小以中小型为主。石核和石片以自然台面者为主,剥片主要采用硬锤锤击法直接剥片,少量应用砸击法。石器有中小型的刮削器、凹缺器和大型的砍砸器,均属简单石核-石片技术产品。本次新发现的旧石器地点进一步扩大了晋陕峡谷地区旧石器时代遗存的时空分布范围,有助于后续相关研究工作的开展。  相似文献   
90.
Rhizoma Paridis, a traditional Chinese medicine, has shown promise in cancer prevention and therapy. Polyphyllin II is one of the most significant saponins in Rhizoma Paridis and it has toxic effects on kinds of cancer cells. However, our results in this study proved that the polyphyllin II has hepatotoxicity in vitro through caspases activation and cell-cycle arrest. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide results indicated polyphyllin II inhibited proliferation, induced apoptosis in HepaRG cells and HL-7702 cells and showed a concentration and time-dependent. Then, we selected the innovative cell model-HepaRG cells to explore the mechanism of hepatotoxicity. Our data showed the reactive oxygen species (ROS) increased and the mitochondrial membrane potential decreased in HepaRG cells after administration of polyphyllin II. Besides, with the increase of concentration, the release of lactate dehydrogenase increased and the S phase of the cell cycle was arrested. Nevertheless, when pretreatment with antioxidant N-acetylcysteine, apoptotic cells decreased significantly, inhibited the production of ROS and improved the decrease of membrane potential in HepaRG cells. Moreover, polyphyllin II treatment increased levels of Fas, Bax, cytochrome c, activated caspase-3, -8, -9, cleaved poly(ADP-ribose) polymerase and decreased Bcl-2 expression levels. Finally, we identified two signal pathways of apoptosis induced by polyphyllin II including the death receptor pathway and the mitochondria pathway. This study confirmed the hepatotoxicity of the polyphyllin II in vitro, which has never been discovered and gave a wake-up call for the clinical application of Rhizoma Paridis.  相似文献   
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