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101.
脱硫催化剂的酸法制备及性能研究 总被引:4,自引:0,他引:4
对用酸法进行催化剂制备,酸法制备的最佳镁铝比,分散介质的优化,引入对脱催化剂的氧化性能和还原性能的影响。以及实验室的还原温度等诸方面进行了研究。 相似文献
102.
Pan Li Guoying Zheng Yan Yang Chunguang Zhang Ping Xiong Yong Xu Min Fang Zheng Tan Fang Zheng Feili Gong 《Cellular and molecular life sciences : CMLS》2010,67(18):3197-3208
When they recognize a target cell, natural killer (NK) cells mount an attack to kill the target by exerting their cytotoxicity
via the exocytosis of cytotoxic granules. Although the details of this process (which includes the movement of cytotoxic granules
in the immune synapse and their fusion with the plasma membrane, releasing granzymes and perforin into the synaptic cleft)
are relatively better understood, the post-exocytosis regulation of the process is still largely unknown. Here we show that
a clathrin-dependent endocytosis stimulated by target cell occurs in NK92 cell line, which is closely correlated with granzyme
B recovery. Inhibition of the endocytosis significantly attenuates the cytotoxicity of NK92 cells. The NK cell recovery of
its released effector molecules, in turn, suggests that endocytosis may well play a key role in the post exocytosis regulation
of immune cells. 相似文献
103.
Ong CK Subimerb C Pairojkul C Wongkham S Cutcutache I Yu W McPherson JR Allen GE Ng CC Wong BH Myint SS Rajasegaran V Heng HL Gan A Zang ZJ Wu Y Wu J Lee MH Huang D Ong P Chan-on W Cao Y Qian CN Lim KH Ooi A Dykema K Furge K Kukongviriyapan V Sripa B Wongkham C Yongvanit P Futreal PA Bhudhisawasdi V Rozen S Tan P Teh BT 《Nature genetics》2012,44(6):690-693
Opisthorchis viverrini-related cholangiocarcinoma (CCA), a fatal bile duct cancer, is a major public health concern in areas endemic for this parasite. We report here whole-exome sequencing of eight O. viverrini-related tumors and matched normal tissue. We identified and validated 206 somatic mutations in 187 genes using Sanger sequencing and selected 15 genes for mutation prevalence screening in an additional 46 individuals with CCA (cases). In addition to the known cancer-related genes TP53 (mutated in 44.4% of cases), KRAS (16.7%) and SMAD4 (16.7%), we identified somatic mutations in 10 newly implicated genes in 14.8-3.7% of cases. These included inactivating mutations in MLL3 (in 14.8% of cases), ROBO2 (9.3%), RNF43 (9.3%) and PEG3 (5.6%), and activating mutations in the GNAS oncogene (9.3%). These genes have functions that can be broadly grouped into three biological classes: (i) deactivation of histone modifiers, (ii) activation of G protein signaling and (iii) loss of genome stability. This study provides insight into the mutational landscape contributing to O. viverrini-related CCA. 相似文献
104.
A rare penetrant mutation in CFH confers high risk of age-related macular degeneration 总被引:1,自引:0,他引:1
105.
随着大涡模拟技术发展日臻成熟及目前计算机运算速度的提高,大涡模拟已经逐渐由理论研究阶段进入工程实用阶段.采用大涡模拟进行超音速燃烧数值模拟时,必须能够准确模拟小尺度上的燃料/空气湍流混合过程及化学反应动力学过程.本文回顾了大涡模拟中的主要亚网格模型及亚网格燃烧模型,总结了国内外采用大涡模拟在超音速燃烧研究领域的应用情况,为大涡模拟的进一步发展和应用提供参考. 相似文献
106.
Tan L Li X Liu F Sun X Li C Zhu Z Fu Y Cai H Wang X Xie D Sun C 《Nature genetics》2008,40(11):1360-1364
The transition from the prostrate growth of ancestral wild rice (O. rufipogon Griff.) to the erect growth of Oryza sativa cultivars was one of the most critical events in rice domestication. This evolutionary step importantly improved plant architecture and increased grain yield. Here we find that prostrate growth of wild rice from Yuanjiang County in China is controlled by a semi-dominant gene, PROG1 (PROSTRATE GROWTH 1), on chromosome 7 that encodes a single Cys(2)-His(2) zinc-finger protein. prog1 variants identified in O. sativa disrupt the prog1 function and inactivate prog1 expression, leading to erect growth, greater grain number and higher grain yield in cultivated rice. Sequence comparison shows that 182 varieties of cultivated rice, including 87 indica and 95 japonica cultivars from 17 countries, carry identical mutations in the prog1 coding region that may have become fixed during rice domestication. 相似文献
107.
用大时宽带宽信号是提高雷达距离、速度及其联合分辨性能的最常用方法之一。频率编码脉冲是一种大时宽带信号,具有良好的距离分辨性能和较窄的瞬时带宽。推导了频率编码脉冲信号及步进频率脉冲信号的模糊函数,分析了其距离、速度分辨性能及其相应关系,并就有效解决其距离-速度联合测量问题进行了讨论。 相似文献
108.
Traditional processes for treating vanadium slag generate a huge volume of solid residue and a large amount of harmful gas, which cause serious environmental problems. In this study, a new process for the comprehensive utilization of vanadium slag was proposed, wherein zeolite A and a V2O5/TiO2 system were synthesized. The structural properties of the as-synthesized zeolite A and the V2O5/TiO2 system were characterized using various experimental techniques, including X-ray diffraction, X-ray fluorescence, scanning electron microscopy, and infrared spectroscopy. The results reveal that zeolite A and the V2O5/TiO2 system are successfully obtained with high purity. The results of gas adsorption measurements indicate that the prepared zeolite A exhibits high selectivity for CO2 over N2 and is a candidate material for CO2 capture from flue-gas streams. 相似文献
109.
根据当前就业形势对以实践性、应用性为主要特色的新闻传播学专业人才的要求,在分析高校专业实践教学存在的问题的基础上,提出高校新闻传播学专业实践教学应加强新闻传播学专业实践教学的规划,创新实践教学的模式,完善专业实践教学基地的建设。 相似文献
110.