排序方式: 共有7条查询结果,搜索用时 0 毫秒
1
1.
目的:探讨M1型巨噬细胞相关因子诱导型一氧化氮合酶(iNOS)、信号传导转录激活因子1(STAT1)在慢性根尖周炎中的表达情况.方法:收集15例慢性根尖周炎患牙的根尖病损组织作为实验组,15例需要拔除第3磨牙的健康牙龈组织作为对照组,采用逆转录-聚合酶链反应(RT-PCR)检测iNOS、STAT1mRNA基因表达情况;用蛋白质印迹法(Western Blot)检测iNOS、STAT1蛋白表达情况.结果:实验组根尖病损组织中iNOS、STAT1mRNA基因和iNOS、STAT1蛋白表达水平明显高于对照组(P0.05).结论:在慢性根尖周炎中M1型巨噬细胞介导的免疫应答增强,表明M1型巨噬细胞参与慢性根尖周炎的发病过程. 相似文献
2.
高效的苜蓿组织培养再生体系的建立 总被引:3,自引:0,他引:3
以保定苜蓿为实验材料,从外植体的基因型、培养基的选择,激素(KT)、水解酪蛋白的浓度等方面探讨了影响保定苜蓿组织培养的因素.结果表明:下胚轴比子叶作为外植体获得的效果更好;改良的SH培养基相对于UM培养基对愈伤组织的诱导更有效;在含有0.2mg/L KT和2 g/L水解酪蛋白的UM培养基上,得到了最大的胚状体诱导率;水解酪蛋白的加入提高了胚状体的质量和成熟率. 相似文献
3.
GE公司是世界上最著名的航空发动机供应商之一,本篇论文研究的是美国GE公司GE90型发动机中的大型机匣零件-高压涡轮机匣新件对其结构研制加工工艺进行详细分析说明。 相似文献
4.
采用溶胶-凝胶法合成了系列Li_2Eu_(4-x)(MoO_4)_7:xYb~(3+)红色荧光粉。研究结果表明Li_2Eu_(3.76)Yb_(0.24)(MoO_4)7在615 nm处发出的红光明显强于未掺杂第二稀土的Li_2Eu_4(MoO_4)_7荧光粉。Yb~(3+)离子掺杂能够将吸收的能量很好地传递给激活离子Eu~(3+),从而起到能量传递的作用。该系列荧光粉可被395 nm的近紫外光和465 nm的可见光有效激发,在615 nm处发射亮红光,对应于Eu~(3+)的~5D_0→~7F_2跃迁,其色度优于商用红粉Y_2O_2S:Eu~(2+),能够用于紫外光和蓝光芯片激发的白光LED用红色荧光粉。 相似文献
5.
A silicon-based field emission light emitting diode for low-voltage operation is fabricated in the standard 0.35 μm 2P4M salieide complementary metal-oxide-semiconduetor (CMOS) technology. Partially overlapping p^+ and n^+ regions with a salicide block layer are employed in this device to constitute a heavily doped p^+-n^+ junction which has soft "knee" Zener breakdown characteristics, thus its working voltage can be reduced preferably below 5 V, and at the same time the power efficiency is improved. The spectra of this device are spread over 500nm to 1000nm with the main peak at about 722nm and an obvious red shift of the spectra peak is observed with the increasing current through the device. During the emission process, field emission rather than avalanche process plays a major role. Differences between low-voltage Zener breakdown emission and high-voltage avalanche breakdown emission performance are observed and compared. 相似文献
6.
Low threshold voltage light-emitting diode in silicon-based standard CMOS technology 总被引:1,自引:0,他引:1
Low-voltage silicon(Si)-based light-emitting diode(LED) is designed based on the former research of LED in Si-based standard complementary metal oxide semiconductor(CMOS) technology.The low-voltage LED is designed under the research of cross-finger structure LEDs and sophisticated structure enhanced LEDs for high efficiency and stable light source of monolithic chip integration.The device size of low-voltage LED is 45.85×38.4(μm),threshold voltage is 2.2 V in common condition,and temperature is 27 ℃.The external quantum efficiency is about 10-6 at stable operating state of 5 V and 177 mA. 相似文献
7.
Face-centered orthorhombic (FCO) sampling can be implemented more easily on CMOS image sensors than on other video acquisition devices. The sampling efficiency of FCO is the highest among all threedimensional (3D) sampling schemes. However, interpolation of FCO-sampled data is inevitable in bridging human perception and machine-vision algorithms. In this letter, the concept of motion compensation is borrowed from deinterlacing, which displays interlaced videos on progressively scanned devices. The combination of motion estimation based on intrafield interpolated frames and motion-compensated interfieldinterpolation is found to provide the best performance by evaluating different combinations of motion estimation and interpolation. 相似文献
1