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71.
多发性骨髓瘤(Multiple myeloma,MM)是恶性克隆性浆细胞疾病,骨髓瘤骨病(Myeloma bone disease,MBD)是其重要的临床表现之一。其发病机理与骨吸收增加及骨生成减少有关,对骨髓瘤骨病病理机制的研究促进了新的靶向性药物研发。现就目前已知参与MBD发病机制及治疗新进展作一综述。 相似文献
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73.
目的建立生物技术产品用重组细胞中鼠细小病毒(Murine minute virus,MMV)污染的检测方法,并进行验证及初步应用。方法以NB324K细胞为指示细胞,建立MMV感染性检测方法,并以不同CCID50的MMV分别感染NB324K细胞,验证方法的灵敏度;通过设计针对编码非结构蛋白1(Non-structural protein 1,NS1)保守序列的引物和探针,建立用于重组细胞中MMV检测的实时荧光定量PCR,并对其线性、特异性、精密性、灵敏度、最低检测限及试验可行性和干扰性进行验证;将NB324K细胞感染试验与荧光定量PCR法相结合,建立NB324K细胞感染-PCR法,并通过对大量样本的检测,分析荧光定量PCR法和NB324K细胞感染-PCR法的可行性。结果 NB324K细胞感染试验的灵敏度为0.2 CCID50;荧光定量PCR检测方法最佳线性范围为1×108~1×104拷贝/μl,R2达0.99以上,特异性良好,与其他种属的细小病毒均无交叉反应,试验内和试验间Ct值的变异系数(CV)均小于5%,试验内病毒定量拷贝数的CV在20%~30%之间,试验间病毒定量拷贝数的CV在20%~50%之间,灵敏度为5×103拷贝/μl,最低感染性病毒颗粒检测限为2 CCID50。该方法能够用于细胞样品中MMV的检测,部分样品基质对病毒的检测具有一定的干扰性。NB324K细胞感染-PCR法的灵敏度为0.02 CCID50,检测时间可缩短为96 h,与荧光定量PCR法分别对47份样品进行检测,结果均为阴性。结论成功建立了MMV荧光定量PCR检测方法和NB324K细胞感染-PCR法,可应用于重组细胞中MMV污染的检测,为进一步提高生产用重组细胞的安全性奠定了基础。 相似文献
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75.
The impactors on cell degradation inside planar SOFC stacks were investigated using both coated and uncoated Fe–16Cr alloys as the interconnects under stable operating conditions at 750 °C and thermal cycling conditions from 750 to 200 °C. It was found that cell degradation inside the stack is primarily dependent on the interfacial contact between the cathode current‐collecting layer and the interconnect. Additionally, cell degradation is found to be independent of the high‐temperature oxidation and Cr vaporization of the interconnects during stack operation, as the stacks are well sealed. The coating on the interconnect can further improve the contact between the cell cathode and the interconnect when the latter is properly embedded into the current‐collecting layer. 相似文献
76.
制绒工艺作为晶体硅太阳能电池生产的重要环节,电池厂商在要求保证工艺质量的前提下,希望能扩大单台设备的产能。介绍了一种用于太阳能电池制绒设备及该系统中关键部件制绒槽和移载机械手。该系统结构简单,控制效果良好,通过对工艺的研究该系统能满足100 MW生产线的生产要求。 相似文献
77.
Titanium incorporated amorphous carbon nitride films were deposited by direct current magnetron sputtering. The films change from amorphous to nanocomposite structure, the relative fraction of sp3 C-N bonding decreases significantly from 2.17 to 1.64 with the increase of Ti content from 2.7 at.% to 12.3 at.%. For the films with high Ti content, the nanocrystalline TiN embedded in a-CNx matrix, while principally TiN did not appear to be well formed for the film containing low Ti content. Potentiodynamic polarization, in vitro human osteoblasts and murine fibroblast cell adhesion tests were employed to assess the corrosion performances of Ti6Al4V alloy coated with the films in Tyrode's solution, and the biocompatibility of Ti-incorporated a-CNx films, respectively. Titanium incorporation increases the corrosion resistance of a-CNx films, and the higher corrosion potential and lower corrosion current density are observed for the alloy coated with the film containing lower Ti content. The high osteoblast adhesion and activation demonstrate the enhanced biocompatibility of Ti alloy coated with Ti-incorporated a-CNx films. The improved biocompatibility in biological environment is attributed to structural change after titanium introduction. 相似文献
78.
T. Liu 《Fuel Cells》2013,13(6):1056-1059
The cobaltate perovskites Sr1–xDyxCoO3–δ (SDCO, x = 0.1, 0.2, 0.3) materials were synthesized and evaluated as cathode for La0.8Sr0.2Ga0.8Mg0.2O3–δ solid electrolyte supported intermediate‐temperature‐solid oxide fuel cells (IT‐SOFCs). The crystal structure of Sr0.9Dy0.1CoO3–δ was defined in the cubic Pm–3m space group (No. 221), Sr0.8Dy0.2CoO3–δ and Sr0.7Dy0.3CoO3–δ had a tetragonal I4/mmm structure. The electrical conductivities were all higher than 100 S cm–1 in the temperature of 170–800 °C. The polarization resistance (Rp) and its activation energy (Ea) increased with increasing x. SEM analysis confirmed the porous microstructure of the SDCO cathodes and good LSGM|LDC|SDCO adherence. Sr0.9Dy0.1CoO3–δ exhibited the best cathode characteristics with a maximum test‐cell power density of 841 mW cm–2, being a high potential candidate of cathode material for IT‐SOFCs. 相似文献
79.
Graphene nanosheets (GS) were formed by the thermal‐expansion method. Large micropores about 1–2 nm were produced, which might provide abundant anchor sites for fixing catalyst. Platinum nanoparticles (NPs) supported on exfoliated GS (Pt/GS) were synthesized through an improved impregnation approach and mixture gas (5% H2 in N2) reduction. SEM and TEM images indicated the simple and clean method can effectively synthesize Pt with uniform dispersion and small size (below 3 nm) on the 2D specific and stratiform GS. The different amounts of Pt loaded on carbon carriers have been investigated respectively to evaluate the preferable electrocatalyst. Experimental results showed that Pt/GS of 20 wt.% initiated CO oxidation at the lowest onset potential in comparison with the commercial Pt/C (JM), indicating a higher CO tolerance of Pt/GS catalysts. In addition, Pt/GS of 20 wt.% exhibited enhanced electrocatalytic activity and high durability towards methanol oxidation. The high performance is exclusively attributed to synergistic effects of exfoliated GS and ultrafine size Pt NPs. Combining a melt‐diffusion strategy with the effective reduction of Pt precursors by the hydrogen gas, this present method is easy to scale up and possesses a significant potential for synthesizing anode electro‐catalyst of direct methanol fuel cells. 相似文献
80.
Boron is a key component in glass and glass–ceramic sealants for planar solid oxide fuel cells (SOFCs). In this paper, the chemical compatibility between boron and commonly used electrolyte and cathode materials of SOFCs such as Y0.16Zr0.84O2 (YSZ), Gd0.1Ce0.9O2 (GDC), La0.8Sr0.2MnO3 (LSM), La0.6Sr0.4Co0.2Fe0.8O3 (LSCF), SrCo0.2Fe0.8O3 (SCF), and (Ba,Sr)(Co,Fe)O3 (BSCF) are studied. The oxide couples with 43 wt.% H3BO3 (equivalent to 30 wt.% B2O3) were heat‐treated at 600–800 °C in air for 20 h. XRD analysis shows that the selected electrolyte and electrode materials are not chemically compatible with boron at temperatures above 600 °C. YSZ and GDC react with boron, forming YBO3 and GdBO3, respectively. In the case of LSM, LSCF, and BSCF powders, the chemical reaction with boron causes the disintegration and decomposition of the perovskite structures. Boron shows a higher reactivity with La2O3 as compared with SrO. On the other hand, the chemical reaction is substantially reduced between volatile boron species and dense electrolyte pellets, but porous electrolyte scaffolds are more susceptible by boron attack as compared to dense electrolyte pellets. The present study suggests that the direct contact between the volatile boron species and electrolyte and cathode materials should be avoided to minimize the detrimental damage of the boron poisoning on the stability and durability of SOFCs. 相似文献