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51.
The assembly of[Et4N][Tp*WS3](1) with CuX (Tp* =hydridotris(3,5-dimethylpyrazol-1-yl)borate;X =Cl,Br,and I) or[Cu(MeCN)4][PF6]in the presence of tetratopic liga... 相似文献
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Bingchao Qi Liqiang Song Lang Hu Dong Guo Gaotong Ren Tingwei Peng Mingchuan Liu Yexian Fang Chunyu Li Mingming Zhang Yan Li 《Experimental & molecular medicine》2022,54(7):946
Myocardial infarction (MI) is the leading cause of premature death among adults. Cardiomyocyte death and dysfunction of the remaining viable cardiomyocytes are the main pathological factors of heart failure after MI. Mitochondrial complexes are emerging as critical mediators for the regulation of cardiomyocyte function. However, the precise roles of mitochondrial complex subunits in heart failure after MI remain unclear. Here, we show that NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1) expression is decreased in the hearts of heart failure patients and mice with myocardial infarction. Furthermore, we found that cardiac-specific Ndufs1 overexpression alleviates cardiac dysfunction and myocardial fibrosis in the healing phase of MI. Our results demonstrated that Ndufs1 overexpression alleviates MI/hypoxia-induced ROS production and ROS-related apoptosis. Moreover, upregulation of Ndufs1 expression improved the reduced activity of complex I and impaired mitochondrial respiratory function caused by MI/hypoxia. Given that mitochondrial function and cardiomyocyte apoptosis are closely related to heart failure after MI, the results of this study suggest that targeting Ndufs1 may be a potential therapeutic strategy to improve cardiac function in patients with heart failure.Subject terms: Heart failure, Myocardial infarction, Myocardial infarction 相似文献
54.
用分子动力学方法模拟了金属铜纳米双晶中晶界在应变作用下的迁移过程,晶界类型为〈11l〉倾侧∑19晶界。原子问相互作用力采用Finnis-Sinclair型EAM势计算。结果表明:平行于晶界方向的压应变可以促进晶界在相邻品界交互作用下发生迁移;垂直于晶界方向的压应变则不能对晶界迁移产生明显的效果。晶界迁移大致可分为两个阶段,前阶段晶界迁移缓慢,随晶界间距减小,晶界间交互作用加强,使晶界迁移显著加速。 相似文献
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In this paper, 5-Fluorouracil (5-FU) loaded carboxylic poly(ε-caprolactone) nanoparticles have been prepared by emulsification/solvent evaporation o/w method, and the drug release behaviors of 5-FU were investigated. The novel carboxylic poly (ε-caprolactone) (P(CL-OPD)-mal) was synthesized via conjugation of maleic anhydride to sodium borohydride (NaBH4) reduced poly(ε-caprolactone-co -4- carbonyl -ε-caprolactone) (P(CL-OPD)), while P(CL-OPD) was synthesized in bulk by ring-opening polymerization of ε-caprolactone and 4-carbonyl-ε-caprolactone (OPD) with stannous octoate as a catalyst. Their structures were confirmed by 1HNMR, FT-IR and GPC. Dynamic light scattering (DLS), transmission electron microscopy (TEM), zeta potential measurements were used for nanoparticle characterization. TEM and DLS showed the nanoparticles were with spherical shape and uniform size distribution (mean diameter 70~100 nm), respectively. Zeta potential analysis revealed that the nanoparticles had an increased negative surface with the increase of carboxyl group concentration. UV spectroscopy was adopted to study the entrapment and release behaviour. The maximum 5-FU loading efficiency was 14.39% with the entrapment efficiency be 42%. In vitro release studies were performed in PBS at 37°C. Results of the study showed that the release behavior can be well-controlled, and the balanced release was up to 96 h. P(CL-OPD)-mal nanoparticles would provide increased benefit in biomedical and pharmaceutical applications. 相似文献
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Lei Wang Chunqiang Yang Qidong Zhang Sheng Wang Hailei Lang Shusheng Zhang Wenjie Zhao Jianxun Zhang 《Journal of separation science》2013,36(16):2664-2671
Tobacco‐specific N‐nitrosamines (TSNAs), including N′‐nitrosonornicotine, 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone, N′‐nitrosoanatabine, and N′‐nitrosoanabasine, have been implicated as a source of carcinogenicity in tobacco and cigarette smoke. We present a rapid and effective method comprising SPE based on tetraazacalix[2]arene[2]triazine‐modified silica as sorbent and analysis with HPLC–MS/MS for the determination of TSNAs and 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanol (NNAL), a metabolite of 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone, in rabbit plasma. The linear dynamic ranges were 10–2000 pg/mL for NNAL and 4–2000 pg/mL for the four TSNAs with good correlation coefficients (>0.9965). The LODs were in the range of 0.9–3.7 pg/mL, and the LOQs were between 2.9 and 12.3 pg/mL. The accuracies of the method were also evaluated and found to be in the range of 90.1–113.3%. This method is promising to be applied to the preconcentration and determination of TSNAs and NNAL in smoke and human body fluids. 相似文献
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Adriaan M. H. van der Veen Hugo Ent Annarita Baldan Valnei S. da Cunha Romeu J. Daroda Brian Lang Michele Schantz Manuela Ulberth-Buchgraber Andrea Held Ruth Hearn Richard J. C. Brown Paul J. Brewer 《Accreditation and quality assurance》2013,18(1):41-50
The main objective of the reference materials for biofuel specifications (BIOREMA) project is the development of two test materials (one bio-ethanol material and one biodiesel material) with well-established reference values. Of a series of three papers, this part describes the material preparation, homogeneity study, stability study, and characterisation of the bio-ethanol material. The test material thus obtained was used in an interlaboratory comparison (ILC) to assess current practices and comparability amongst laboratories providing bio-ethanol testing services. Only 13 participants provided data, resulting in a small dataset for evaluation. Further, it appeared that for a number of laboratories, there was not sufficient material for the determination of all requested parameters. In most cases, as far as the data permit, it can be concluded that the consensus values (based on participant’s results) are in good agreement with the reference or the BIOREMA values (obtained by NMIs participating in the project). For three parameters, namely ethanol content, water content, and density, there is good agreement between the reference and consensus values. For these parameters, the reproducibility standard deviation is close to, or even smaller than, the expanded uncertainty associated with the reference value. A number of parameters show very poor reproducibility, for example, pHe, electrolytic conductivity, and acidity. The same applies to sodium and copper content, which are very low and therefore challenging parameters to measure accurately. The results of the ILC underpin the need for certified reference materials and demonstrate the requirement for more robust quality control to improve the precision and trueness of the results from testing laboratories. 相似文献