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11.
Quintana FJ Basso AS Iglesias AH Korn T Farez MF Bettelli E Caccamo M Oukka M Weiner HL 《Nature》2008,453(7191):65-71
12.
论述了从塞拉利昂不同地区采集的6个粘土试样的一些物理性能,这些物理性能与无釉烧结地砖的耐压强度有一定的关系。由相关系数可知,烧结温度是控制地砖强度的主要因素,虽然粘土的粒度分布与地砖强度之间无明显关系,但过多添加砂子会降低砖的强度,而适当的粘土和淤泥则提高砖的强度。高塑性有降低砖强度的作用,体积密度和气孔率对强度有相反的影响,前者能提高强度,而后者则会降低砖的强度。 相似文献
13.
Zhang Z Lee JC Lin L Olivas V Au V LaFramboise T Abdel-Rahman M Wang X Levine AD Rho JK Choi YJ Choi CM Kim SW Jang SJ Park YS Kim WS Lee DH Lee JS Miller VA Arcila M Ladanyi M Moonsamy P Sawyers C Boggon TJ Ma PC Costa C Taron M Rosell R Halmos B Bivona TG 《Nature genetics》2012,44(8):852-860
Human non-small cell lung cancers (NSCLCs) with activating mutations in EGFR frequently respond to treatment with EGFR-targeted tyrosine kinase inhibitors (TKIs), such as erlotinib, but responses are not durable, as tumors acquire resistance. Secondary mutations in EGFR (such as T790M) or upregulation of the MET kinase are found in over 50% of resistant tumors. Here, we report increased activation of AXL and evidence for epithelial-to-mesenchymal transition (EMT) in multiple in vitro and in vivo EGFR-mutant lung cancer models with acquired resistance to erlotinib in the absence of the EGFR p.Thr790Met alteration or MET activation. Genetic or pharmacological inhibition of AXL restored sensitivity to erlotinib in these tumor models. Increased expression of AXL and, in some cases, of its ligand GAS6 was found in EGFR-mutant lung cancers obtained from individuals with acquired resistance to TKIs. These data identify AXL as a promising therapeutic target whose inhibition could prevent or overcome acquired resistance to EGFR TKIs in individuals with EGFR-mutant lung cancer. 相似文献
14.
RK Koenekoop H Wang J Majewski X Wang I Lopez H Ren Y Chen Y Li GA Fishman M Genead J Schwartzentruber N Solanki EI Traboulsi J Cheng CV Logan M McKibbin BE Hayward DA Parry CA Johnson M Nageeb;Finding of Rare Disease Genes 《Nature genetics》2012,44(9):1035-1039
Leber congenital amaurosis (LCA) is a blinding retinal disease that presents within the first year after birth. Using exome sequencing, we identified mutations in the nicotinamide adenine dinucleotide (NAD) synthase gene NMNAT1 encoding nicotinamide mononucleotide adenylyltransferase 1 in eight families with LCA, including the family in which LCA was originally linked to the LCA9 locus. Notably, all individuals with NMNAT1 mutations also have macular colobomas, which are severe degenerative entities of the central retina (fovea) devoid of tissue and photoreceptors. Functional assays of the proteins encoded by the mutant alleles identified in our study showed that the mutations reduce the enzymatic activity of NMNAT1 in NAD biosynthesis and affect protein folding. Of note, recent characterization of the slow Wallerian degeneration (Wld(s)) mouse model, in which prolonged axonal survival after injury is observed, identified NMNAT1 as a neuroprotective protein when ectopically expressed. Our findings identify a new disease mechanism underlying LCA and provide the first link between endogenous NMNAT1 dysfunction and a human nervous system disorder. 相似文献
15.
Two modified electrodes (Pb/PbO2 and C/PbO2) were prepared by electrodepositing a lead oxide layer on lead and carbon substrates. These modified electrodes were used as anodes for the generation of sodium hypochlorite (NaOCl) from sodium chloride solution. Different operating conditions and factors affecting the treatment process of NaOCl generation, including current density, pH values, conductive electrolytes, and electrolysis time, were studied and optimized. By comparison the C/PbO2 electrode shows a higher efficiency than the Pb/PbO2 electrode for the generation of NaOCl. 相似文献
16.
17.
Many functionally important cellular peptides and proteins, including hormones, neuropeptides, and growth factors, are synthesized
as inactive precursor polypeptides, which require post-translational proteolytic processing to become biologically active
polypeptides. This is achieved by the action of a relatively small number of proteases that belong to a family of seven subtilisin-like
proprotein convertases (PCs) including furin. In view of this, this review focuses on the importance of privileged secondary
structures and of given amino acid residues around basic cleavage sites in substrate recognition by these endoproteases. In
addition to their participation in normal cell functions, PCs are crucial for the initiation and progress of many important
diseases. Hence, these proteases constitute potential drug targets in medicine. Accordingly, this review also discusses the
approaches used to shed light on the cleavage preference and the substrate specificity of the PCs, a prerequisite to select
which PCs are promising drug targets in each disease. 相似文献
18.
由对叔丁基苯酚和甲醛在碱催化下以一步法合成了对叔丁基杯〔8〕芳烃.以酸酐和酰卤为酰基化试剂合成了相应的酯类衍生物.讨论了杯芳烃的分子结构与光谱性质的关系 相似文献
19.
Effect of the synthesis route on the structural and dielectric properties of SrBi<Subscript>1.8</Subscript>Y<Subscript>0.2</Subscript>Nb<Subscript>2</Subscript>O<Subscript>9</Subscript> ceramics 下载免费PDF全文
Mohamed Afqir Amina Tachafine Didier Fasquelle Mohamed Elaatmani Jean-Claude Carru Abdelouahad Zegzouti Mustapha El Hammioui 《矿物冶金与材料学报》2018,25(11):1304-1312
This work is devoted to the synthesis and characterization of yttrium-doped SrBi2Nb2O9 ceramics prepared by three methods: solid state reaction, co-precipitation, and hydrothermal. Multiple characterizations, specifically scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), were used to validate the structural feature. The crystallite size was estimated by Scherrer’s formula and the Williamson–Hall plot. The effect of the process on the band intensities of the FTIR spectra was investigated. The crystallite size and microstructure of ceramics prepared from different synthesis processes were strongly influenced by the sinterability. SEM images revealed nanograin ceramics for materials prepared by co-precipitation and hydrothermal methods and micrograin ceramics prepared by the solid state method. The synthesized compounds underwent phase transitions at 480–465°C. The dielectric and electrical properties of these Y-doped SrBi2Nb2O9 ceramics appear to be dependent on the grain size. 相似文献
20.
T helper (T(H)) cells constitute an important arm of the adaptive immune system because they coordinate defence against specific pathogens, and their unique cytokines and effector functions mediate different types of tissue inflammation. The recently discovered T(H)17 cells, the third subset of effector T helper cells, have been the subject of intense research aimed at understanding their role in immunity and disease. Here we review emerging data suggesting that T(H)17 cells have an important role in host defence against specific pathogens and are potent inducers of autoimmunity and tissue inflammation. In addition, the differentiation factors responsible for their generation have revealed an interesting reciprocal relationship with regulatory T (T(reg)) cells, which prevent tissue inflammation and mediate self-tolerance. 相似文献