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排序方式: 共有142条查询结果,搜索用时 15 毫秒
51.
Under new assumptions, this paper obtains some extended versions of Ky Fan type inequality for a family of C-continuous set-valued mappings in the setting of topological semilattices. The obtained results are new and different from the corresponding known results in the literature. Some special cases of the main result are also discussed. Some examples are given to illustrate the results. 相似文献
52.
The accessible chromatin landscape of the human genome 总被引:2,自引:0,他引:2
RE Thurman E Rynes R Humbert J Vierstra MT Maurano E Haugen NC Sheffield AB Stergachis H Wang B Vernot K Garg S John R Sandstrom D Bates L Boatman TK Canfield M Diegel D Dunn AK Ebersol T Frum E Giste AK Johnson EM Johnson T Kutyavin B Lajoie BK Lee K Lee D London D Lotakis S Neph F Neri ED Nguyen H Qu AP Reynolds V Roach A Safi ME Sanchez A Sanyal A Shafer JM Simon L Song S Vong M Weaver Y Yan Z Zhang Z Zhang B Lenhard M Tewari MO Dorschner RS Hansen PA Navas G Stamatoyannopoulos VR Iyer 《Nature》2012,489(7414):75-82
53.
Wang K Diskin SJ Zhang H Attiyeh EF Winter C Hou C Schnepp RW Diamond M Bosse K Mayes PA Glessner J Kim C Frackelton E Garris M Wang Q Glaberson W Chiavacci R Nguyen L Jagannathan J Saeki N Sasaki H Grant SF Iolascon A Mosse YP Cole KA Li H Devoto M McGrady PW London WB Capasso M Rahman N Hakonarson H Maris JM 《Nature》2011,469(7329):216-220
54.
Dopamine neurons derived from embryonic stem cells function in an animal model of Parkinson's disease 总被引:112,自引:0,他引:112
Kim JH Auerbach JM Rodríguez-Gómez JA Velasco I Gavin D Lumelsky N Lee SH Nguyen J Sánchez-Pernaute R Bankiewicz K McKay R 《Nature》2002,418(6893):50-56
Parkinson's disease is a widespread condition caused by the loss of midbrain neurons that synthesize the neurotransmitter dopamine. Cells derived from the fetal midbrain can modify the course of the disease, but they are an inadequate source of dopamine-synthesizing neurons because their ability to generate these neurons is unstable. In contrast, embryonic stem (ES) cells proliferate extensively and can generate dopamine neurons. If ES cells are to become the basis for cell therapies, we must develop methods of enriching for the cell of interest and demonstrate that these cells show functions that will assist in treating the disease. Here we show that a highly enriched population of midbrain neural stem cells can be derived from mouse ES cells. The dopamine neurons generated by these stem cells show electrophysiological and behavioural properties expected of neurons from the midbrain. Our results encourage the use of ES cells in cell-replacement therapy for Parkinson's disease. 相似文献
55.
偶联剂对HDPE基竹塑复合材料性能的影响 总被引:1,自引:0,他引:1
以高密度聚乙烯(HDPE)、竹粉(BF)为原料,马来酸酐接枝聚丙烯(MAH-g-PP)作为偶联剂,通过混炼、平板热压成型制备竹粉/HDPE复合材料,研究了马来酸酐接枝聚丙烯添加量(0、2%、5%、8%)对竹粉/HDPE复合材料吸湿性、吸水性、弯曲强度、拉伸强度以及抗冲击强度等性能的影响。结果表明:MAH-g-PP能显著改善竹粉/HDPE复合材料的吸湿、吸水性能,明显提高复合材料的力学性能; 当MAH-g-PP添加量为5%时,复合材料的吸湿、吸水率最低,静曲强度与弹性模量分别提高68%和30.4%,拉伸强度与抗冲击强度分别增长53.7%和75%; 而当MAH-g-PP添加量为8%时,复合材料的力学性能在一定程度上有所降低。红外光谱(FTIR)分析显示,添加MAH-g-PP后竹粉的游离羟基与马来酸酐之间发生了酯化反应。 相似文献
56.
Thi Ngoc Tram Nguyen Diem-Huong Nguyen-Tran Long Giang Bach Tran Hoang Du Truong Ngoc Thuy Trang Le Dai Hai Nguyen 《自然科学进展(英文版)》2019,29(6):612-616
A hybrid of organic/inorganic system, hollow mesoporous silica nanoparticles functionalized with poly(ethylene glycol), was synthesized in the presence of coupling agent and aminated ends. Doxorubicin (DOX) was used as a model drug to evaluate the effect of PEGylation on the loading capacity and release pattern of the system. Characterization with transmission electron microscopy (TEM) and scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption-desorption, thermogravimetric analysis (TGA) and Fourier transformed infrared (FTIR) confirmed the PEG conjugation, as well as the amorphous mesoporous nature of the synthesized particles. Due to the capping effect of PEG molecules over the pores in the silica structure, the synthesized system was able to retain higher amount of cargo and establish a controlled manner when releasing. 相似文献
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59.
Tuan M. Ha Ockie J. H. Bosch Nam C. Nguyen 《Systemic Practice and Action Research》2016,29(3):261-275
This paper reports on a case study on improving the quality of life for women smallholder farmers in Vietnam, using the systems-based Evolutionary Learning Laboratory (ELLab) approach. The study aims to provide evidence of practical contributions of the ELLab to project stakeholder and knowledge management through the case study. A transformative learning framework was developed to provide initial reflections on the planning phase of the project. Practical contributions of the ELLab process to stakeholder identification and management, and knowledge creation during project planning and implementation are discussed. Strong evidence was found of transformations in awareness and perspectives amongst project actors that subsequently led to systemic and executable action plans. This clearly proved the value of the ELLab approach in informal transformative learning. 相似文献
60.