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991.
992.
目的:研究连翘酯苷A(Forsythiaside A,FA)对缺血再灌注引起的脑细胞损伤的保护作用及机制.方法:采用PC12细胞缺氧再复氧模型(OGD/R),细胞分组为正常组,模型组,FA处理组(1.25,2.5和5μmol/L),测定细胞存活率、凋亡率、ROS、MDA以及抗氧化酶水平.采用Western blotti...  相似文献   
993.
毛彬彬  张巧仙  方云  林尽 《蛇志》2021,(1):74-76
目的 探讨PDCA循环在提高肿瘤患者输液港护理依从性的应用效果.方法 选取2018年2~8月我院收治的504例输液港置管的肿瘤患者按随机分配原则分为对照组240例和观察组264例,对照组给予一般治疗和常规管理,观察组在对照组基础上实施PDCA循环管理,观察两组患者的并发症发生情况、输液港护理依从性,并进行统计分析.结果...  相似文献   
994.
995.
Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma and has the highest mortality rate. For metastatic RCC, systemic drug therapy is the most important method in addition to surgical tumor reduction. In recent years, tyrosine kinase inhibitors (TKIs) targeting the angiogenesis have been applied to treat ccRCC and achieved profound therapeutic effects. It has been reported that most patients receiving antiangiogenic therapy will develop resistance within 15 months. The mechanism of resistance to targeted therapy is extremely complex and has not been clarified. Ovarian tumor-associated protease domain-containing proteins (OTUDs) belonging to DUBs play a critical role in the tumorigenesis of solid tumors. However, the specific role of OTUDs in ccRCC is still elusive. Here, we investigated the clinicopathological role of OTUD family members in ccRCC. We demonstrated that OTUD1 was downregulated in renal cancer and involved in the poor prognosis of renal cancer. Then, we showed that OTUD1 inhibits cancer cell growth. Moreover, analysis of OTUD1 RNA-seq data indicated that OTUD1 inhibition triggers the AKT and NF-kappa B pathways in renal cancer cells. Furthermore, OTUD1 interacts with PTEN and regulates its stability. Subsequently, we revealed that downregulation of OTUD1 contributes to the sensitivity of renal cancer cells to TKIs, and this effect was blocked by TNF/NF-kappa B inhibitors and AKT inhibitors. Thus, we identified that the OTUD1-PTEN axis suppresses tumor growth and regulates the resistance of renal cancer to TKIs.  相似文献   
996.
铁是影响初级生产力的主要限制性因子之一,其在海洋环境中的分布具有空间异质性。由于铁在海洋中主要以溶解度较低、易沉降的三价态(Fe3+)形式存在,因此溶解铁对海洋生物而言是一种稀缺资源。为了获得生命代谢所需的铁,微生物进化出多种铁摄取的策略来满足需求,其中铁载体(siderophores)是最典型的代表。铁载体作为重要的代谢辅因子,除了铁循环以外,也强烈影响着其他元素的循环。基于铁载体的重要性,深入理解它的合成、转运和调控机制是系统认识海洋铁循环和生命过程的重要环节之一。本文以近20年的研究为重点,总结了铁载体的最新进展,包括其类型、合成/运输系统、获取途径、调控机制以及铁载体的功能与应用,旨在更好地认识铁载体在海洋微生物生态学过程中的作用,加深对海洋铁循环动力学机制的理解。  相似文献   
997.
998.
Tissue homeostasis requires lineage fidelity of stem cells. Dysregulation of cell fate specification and differentiation leads to various diseases, yet the cellular and molecular mechanisms governing these processes remain elusive. We demonstrate that YAP/TAZ activation reprograms airway secretory cells, which subsequently lose their cellular identity and acquire squamous alveolar type 1 (AT1) fate in the lung. This cell fate conversion is mediated via distinctive transitional cell states of damage‐associated transient progenitors (DATPs), recently shown to emerge during injury repair in mouse and human lungs. We further describe a YAP/TAZ signaling cascade to be integral for the fate conversion of secretory cells into AT1 fate, by modulating mTORC1/ATF4‐mediated amino acid metabolism in vivo. Importantly, we observed aberrant activation of the YAP/TAZ‐mTORC1‐ATF4 axis in the altered airway epithelium of bronchiolitis obliterans syndrome, including substantial emergence of DATPs and AT1 cells with severe pulmonary fibrosis. Genetic and pharmacologic inhibition of mTORC1 activity suppresses lineage alteration and subepithelial fibrosis driven by YAP/TAZ activation, proposing a potential therapeutic target for human fibrotic lung diseases.  相似文献   
999.
1000.
Apoptin is a small molecular weight protein encoded by the VP3 gene of chicken anemia virus (CAV). It can induce apoptosis of tumor cells and play anti-tumorigenic functions. In this study, we identified a time-dependent inhibitory role of apoptin on the viability of HCT116 cells. We also demonstrated that apoptin induces pyroptosis through cleaved caspase 3, and with a concomitant cleavage of gasdermin E (GSDME) rather than GSDMD. GSDME knockdown switched the apoptin-induced cell death from pyroptosis to apoptosis in vitro. Furthermore, we demonstrated that the effect of apoptin on GSDME-dependent pyroptosis could be mitigated by caspase-3 and caspase-9 siRNA knockdown. Additionally, apoptin enhanced the intracellular reactive oxygen species (ROS), causing aggregation of the mitochondrial membrane protein Tom20. Moreover, bax and cytochrome c were released to the activating caspase-9, eventually triggering pyroptosis. Therefore, GSDME mediates the apoptin-induced pyroptosis through the mitochondrial apoptotic pathway. Finally, using nude mice xenografted with HCT116 cells, we found that apoptin induces pyroptosis and significantly inhibits tumor growth. Based on this mechanism, apoptin may provide a new strategy for colorectal cancer therapy.  相似文献   
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