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101.
LIVIN, a member of the inhibitor of apoptosis proteins (IAPs), is reported playing important roles in the development and progression of multiple human cancers. However, its underlined mechanisms in human renal cell carcinoma (RCC) are still needed to be clarified. In the present study, we reported that inhibition of miR-214 promoted the expression of LIVIN, then facilitated RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs. In constant, overexpression of miR-214 had contradictory effects. Further investigation showed that miR-214 was down-regulated in RCC because of abnormal methylation. In addition, DNA methyltransferase DNMT1, miR-214 and LIVIN are directly correlated in RCC patients. In conclusion, these results suggest that abnormal miR-214 methylation negatively regulates LIVIN, which may promote RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs.  相似文献   
102.
In order to find novel antitumor candidate agents with high efficiency and low toxicity, 14 novel substituted 5‐anilino‐α‐glucofuranose derivatives have been designed, synthesized and evaluated for antiproliferative activities in vitro. Their structures were characterized by NMR (1H and 13C) and HR‐MS, and configuration (R/S) at C(5) was identified by two‐dimensional 1H,1H‐NOESY‐NMR spectrum. Their antiproliferative activities against human tumor cells were investigated by MTT assay. The results demonstrated that most of the synthesized compounds had antiproliferative effects comparable to the reference drugs gefitinib and lapatinib. In particular, (5R)‐5‐O‐(3‐chloro‐4‐{[5‐(4‐fluorophenyl)thiophen‐2‐yl]methyl}anilino)‐5‐deoxy‐1,2‐O‐(1‐methylethylidene)‐α‐glucofuranose ( 9da ) showed the most potent antiproliferative effects against SW480, A431 and A549 cells, with IC50 values of 8.57, 5.15 and 15.24 μm , respectively. This work suggested 5‐anilino‐α‐glucofuranose as an antitumor core structure that may open a new way to develop more potent anti‐cancer agents.  相似文献   
103.
Three dimeric cassane diterpenoids, caesalpanins A–C, were isolated from the seeds of Caesalpinia sappan L., as well as three known compounds. Their structures were determined via analysis of 1D‐, 2D‐NMR, and HR‐ESI‐MS data. Caesalpanins A and B were the second and third compounds that presented a nitrogen‐containing cassane diterpenoid dimer linked through one ether bond between C‐19 and C‐20′. Caesalpanin B exhibited moderate cytotoxic activity against MCF‐7 cell lines with IC50 value of 29.98 μm . Caesalpanins A and B had weak inhibitory effects against LPS‐induced nitric oxide (NO) production in RAW 264.7 macrophages at 50 μm with inhibitory rate of 36.01 % and 32.93 %, respectively.  相似文献   
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Transition metal sulfides hold promising potentials as Li‐free conversion‐type cathode materials for high energy density lithium metal batteries. However, the practical deployment of these materials is hampered by their poor rate capability and short cycling life. In this work, the authors take the advantage of hollow structure of CuS nanoboxes to accommodate the volume expansion and facilitate the ion diffusion during discharge–charge processes. As a result, the hollow CuS nanoboxes achieve excellent rate performance (≈371 mAh g?1 at 20 C) and ultra‐long cycle life (>1000 cycles). The structure and valence evolution of the CuS nanobox cathode are identified by scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. Furthermore, the lithium storage mechanism is revealed by galvanostatic intermittent titration technique and operando Raman spectroscopy for the initial charge–discharge process and the following reversible processes. These results suggest that the hollow CuS nanobox material is a promising candidate as a low‐cost Li‐free cathode material for high‐rate and long‐life lithium metal batteries.  相似文献   
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Developing a titanium dioxide (TiO2)‐based anode with superior high‐rate capability and long‐term cycling stability is important for efficient energy storage. Herein, a simple one‐step approach for fabricating blue TiO2 nanoparticles with oxygen vacancies is reported. Oxygen vacancies can enlarge lattice spaces, lower charge transfer resistance, and provide more active sites in TiO2 lattices. As a result, this blue TiO2 electrode exhibits a highly reversible capacity of 50 mAh g?1 at 100 C (16 800 mA g?1) even after 10 000 cycles, which is attributable to the combination of surface capacitive process and remarkable diffusion‐controlled insertion revealed by the kinetic analysis. The strategy of employing oxygen‐deficient nanoparticles may be extended to the design of other robust semiconductor materials as electrodes for energy storage.  相似文献   
110.
目的:探讨沐舒坦联合布地奈德雾化治疗新生儿胎粪吸入综合征的临床效果及安全性。方法:选择2017年1月~2018年2月我院新生儿科收治的76例新生儿胎粪吸入综合征患儿,按照随机数字表法将其分成两组,每组38例。对照组患者采用布地奈德雾化治疗,观察组在对照组的治疗基础上加用沐舒坦治疗,分析和比较两组的治疗效果,患儿治疗前后动脉血气分析指标变化以及预后情况。结果:治疗后,观察组临床总有效率明显高于对照组,观察组呼吸困难缓解时间、肺部湿罗音消失时间、发绀消失时间、血氧饱和度恢复时间均显著较对照组短(P0.05)。两组患儿治疗后PaCO_2、FIO_2、OI均较治疗前降低,PaO_2均较治疗前上升,其中观察组PaCO_2、FIO_2、OI明显低于对照组,PaO_2高于对照组,上述差异均具有统计学意义(P0.05)。观察组总并发症发生率显著低于对照组(P0.05),患儿治愈率显著高于对照组(P0.05),两组死亡率比较差异无统计学意义(P0.05)。结论:与布地奈德雾化治疗相比,沐舒坦联合布地奈德雾化治疗新生儿胎粪吸入综合征患儿可以更有效缩短临床症状改善时间,改善患儿肺功能及预后,且安全性更高。  相似文献   
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