Hsa—miR-200a真核表达载体的构建及鉴定

目的：通过构建及鉴定miR-200a的真核表达载体pcDNA3．1（＋）-miR-200a,为进一步研究miR-200a的功能奠定实验基础。方法：RT-PCR扩增pre—miR-200a基因序列,连接于表达载体pcDNA3．1（＋）中,对重组质粒双酶切鉴定并测序验证。结果：pcDNA3．1（＋）-miR-200a真核表达载体经酶切及测序鉴定正确。结论：pcDNA3．1（＋）-miR-200a真核表达载体构建成功,为下一步深入研究miR-200a的生物学功能和验证miR-200a的靶基因提供有效工具。     

三氧化二砷对照射后人肺癌细胞MGMT和VEGF表达的影响

目的：本文探讨三氧化二砷（Arsenic trioxide,As2O3）对受照后人肺癌A2细胞株MGMT和VEGF表达的影响。方法：设立空白对照组、照射组（直线加速器X射线照射,2Gy）、As2O3组（1.0μmol/L As2O3）、As2O3＋照射组（1.0μmol/L As2O3＋X射线照射,2Gy）。平板克隆形成试验测定各实验组细胞集落形成率,用RT-PCR和免疫组化检测MGMT（甲基鸟嘌呤甲基转移酶）、VEGF（血管内皮生长因子）基因和蛋白水平的变化。结果：As2O3＋照射组细胞集落形成率较As2O3组及照射组明显下降,与As2O3组或照射组比较差异具有显著性（P〈0.01）。As2O3＋照射组细胞MGMT、VEGF基因表达明显减少,而且MGMT、VEGF蛋白的表达明显降低,与As2O3组或照射组比较差异具有显著性（P〈0.01）。结论：As2O3能使受照后人肺癌A2细胞MGMT、VEGF基因及蛋白表达水平明显下调,可能是As2O3对人肺癌细胞辐射增敏的机制之一。     

原代大鼠肾小球系膜细胞最佳电转染条件的探索和验证

目的探索并验证原代大鼠肾小球系膜细胞最佳电转染条件。方法设立不同的电压与电容组合、电击前孵育温度、质粒DNA浓度等电转染条件,将绿色荧光蛋白表达质粒pEGFP-C1导入原代大鼠肾小球系膜细胞。24h后比较各组细胞存活率和绿色荧光蛋白表达情况,确立最佳电转染条件。再以此条件电转染质粒pcDNA3.1和pcDNA3.1-FHL2,48h后收取两组细胞RNA和蛋白。应用RT-PCR和Western印迹检测目的基因FHL2的核酸和蛋白表达,验证电转染效果。结果在电击前室温孵育,40μg质粒,340V电压、550μF电容的最佳电转染条件下,原代大鼠肾小球系膜细胞的电转染效率可达40%以上,细胞存活率在50%左右。转染FHL2质粒组较对照组检测FHL2的核酸和蛋白表达水平明显升高(P<0.05)。结论适当的电转染条件可以有效转染原代大鼠肾小球系膜细胞。     

XIAP表达水平对5-Fu诱导肝癌细胞凋亡的影响

目的研究XIAP mRNA及蛋白表达水平对不同剂量5-氟尿嘧啶（5-fluorouracil,5-Fu）诱导人肝癌细胞HepG2凋亡的影响。方法脂质体介导含XIAP基因全长的质粒pef-XIAP转染人肝癌细胞HepG2,采用逆转录聚合酶链反应（RT—PCR）及western blotting检测XIAP基因和蛋白表达水平。通过不同剂量5-Fu诱导细胞凋亡,使用CCK-8试剂通过比色法分析检测5-Fu对转染pef-XIAP的HepG2细胞生长活性的抑制作用。结果各组HepG2细胞在不同剂量的5-Fu诱导下发生凋亡、与普通HepG2细胞组比较．转染XIAP基因的HepG2细胞组的凋亡率显著降低。结论XIAP基因在人肝癌细胞HepG2中的高表达可以明显降低化疗药物5-Fu诱导的细胞凋亡,其可能在肝癌化疗耐药中起一定作用。     

重组人骨形态发生蛋白9和2体外诱导成骨的活性分析

利用PCR扩增hBMP-9全长序列构建真核表达载体pcDNA4／HisMax—BMP-9,与质粒pSV2-dhfr共转染CHO—dhfr-细胞,以含有100μg／ml博来霉素的1MDM进行选择性培养,筛选抗性克隆,并用MTX扩增,提高rhBMP-9的表达量。经过细胞分离培养,得到稳定表达rhBMP-9的6株单克隆细胞株,ELISA法检测rhBMP-9表达水平,最高可达1．13μg/24h／10^6cells。收集最高表达蛋白的单克隆株培养基上清,经His标签的蛋白纯化柱纯化,冻干法浓缩得到100μm/ml的rhBMP-9。用浓度100μg／ml的rhBMP-9和rhBMP-2分别刺激培养C3H10,各项成骨指标显示rhBMP-9具有-定的体外诱导成骨能力,但不及rhBMP-2。     

人二型大麻受体基因的pIRES2-EGFP质粒的构建及其真核表达

目的：构建含有人二型大麻素受体（CB2）基因的真核表达载体,并实现其在HEK293细胞的表达。方法：首先采用PCR方法从含有CB2基因的质粒pcDNA3.1（＋）-CB2中扩增获得人的CB2基因,再采用基因重组技术将CB2的DNA片段插入真核表达载体pIRES2-EGFP。将获得的pIRES2-EGFP-CB2重组子转染HEK293细胞,应用荧光显微镜观察EGFP的表达情况,RT-PCR和报告基因检测CB2的表达情况。结果：酶切和测序结果验证真核表达载体pIRES2-EGFP-GB2构建成功。可在荧光显微镜下观察到转染HEK293细胞表达的绿色荧光;RT-PCR和双荧光素酶报告基因法检测证明CB2蛋白在真核细胞中成功表达;CB2受体激动剂JWH-015能显著逆转腺苷酸环化酶激动剂forskolin诱发的荧光素酶活性增加。结论：成功构建了真核表达载体pIRES2-EGFP-CB2,为进一步研究CB2基因的生理学和病理生理学功能及调控机制奠定了实验基础。     

肺癌中EGFR蛋白表达和基因扩增相关性研究

目的对肺癌EGFR蛋白表达和基因扩增进行比较分析：方法对2004年至2006年期间本院病理科常规病理诊断中确诊为啼腺癌和BAC的病例按照2004年WHO最新肺肿瘤分类标准重新分类，应用组织芯片、免疫组织化学和FISH技术对总计89例肺癌进行EGFR蛋白表达和基因扩增的检测.结果经典型肺腺癌EGFR蛋白的阳性表达率为56．52％，基因扩增率为45．45％；混合亚型肺腺癌EGFR蛋白的阳性表达率为20．51％，基因扩增率为22．58％；BAC病例中的EGFR蛋白的表达率为3．85％，扩增率为14．81％。经典型肺腺癌EGFR的蛋白表达阳性病例和基因扩增病例均明显多于BAC和混合亚型肺腺癌，（P〈0．05）。EGFR蛋白表达和基因扩增之间存在正相关（P〈0．005）：结论EGFR基因的扩增及蛋白的表达在肺腺癌病例中均高于BAC，EGFR基因扩增与蛋白表达之间存在相关关系。     

烟夜蛾性信息素结合蛋白2(PBP2)基因的克隆、序列分析与时空表达

性信息素结合蛋白(pheromone binding proteins,PBPs)在昆虫雌雄间信息交流中起着重要作用。本研究利用RT-PCR和RACE方法,从烟夜蛾Helicoverpa assulta(Guen&#233;e)雄虫触角中克隆了性信息素结合蛋白2基因的开放阅读框及3′末端序列,该基因被命名为HassPBP2(GenBank登录号为EU316186)。克隆和测序结果表明,HassPBP2开放阅读框全长450bp,编码149个氨基酸残基,推测编码蛋白的分子量为16.9kD,等电点为5.56。HassPBP2基因结构分析表明,该基因由3个外显子和2个内含子组成,内含子的长度分别为90和261bp。氨基酸序列联配分析表明,此序列具有气味结合蛋白的典型特征,与其他鳞翅目昆虫PBPs的一致性在34%~91%之间,其中与棉铃虫Helicoverpa armigeraPBP2和烟芽夜蛾Heliothis virescensPBP2的序列一致性高达91%。时间表达和组织表达分析显示,HassPBP2在卵期、幼虫期和蛹早期不表达,在蛹中期开始表达,并一直持续到成虫中期,且只在雌、雄成虫触角中表达。     

二氧化锡/多孔硅/硅光伏特性研究

测量了二氧化锡（SnO2）／多孔硅（PS）／硅（Si）的光电压谱，分析表明：在SnO2／PS／Si材料中存在着两个异质结；当样品吸附还原性气体时，其光电压明显下降。当样品在1％液化石油气的氛围时（相对于空气），光电压减少了16．4％-27．5％；在1％CO氛围时，减少了8．1％-19．4％；在1％H2氛围时，减少了12．1％-14．9％，因此SnO2／PS／Si可作为一种新的敏感元件。文中还对测量结果进行了讨论分析。     

丹参酮ⅡA增效大鼠骨髓源性内皮祖细胞VEGF、SDF-1表达

目的：研究在丹参酮ⅡA的辅助下,骨髓源性内皮祖细胞（EPCs）VEGF与SDF-1表达是否能增强,从而促进细胞归巢。方法：Percoll密度梯度离心法分离SD大鼠骨髓单个核细胞,血管内皮生长因子（VEGF）、表皮生长因子（（EGF）、碱性成纤维细胞生长因子（bFGF）诱导培养,并进行形态学、免疫学（免疫细胞化学染色）、功能学（Dil-acLDL与FITC-UEA-1双荧光染色）鉴定。将鉴定为EPCs的细胞分为单纯EPCs组（对照组）、EPCs＋丹参酮ⅡA组（加药组）。细胞培养第9d,Western blot与实时荧光定量PCR检测各组VEGF、SDF-1基因与蛋白表达。结果：EPCs＋丹参酮IIA组VEGF、SDF-1基因与蛋白表达均高于EPCs组（p均〈0.05）。结论：丹参酮ⅡA可上调大鼠骨髓源性内皮祖细胞VEGF及SDF-1表达,从而可能在缺血环境中更好促进EPCs归巢,更有效促进血管修复与再生。     

Design of a fully differential CMOS LNA for 3.1-10.6 GHz UWB communication systems

A fully differential complementary metal oxide semiconductor （CMOS） low noise amplifier （LNA） for 3.1-10.6 GHz ultra-wideband （UWB） communication systems is presented. The LNA adopts capacitive cross-coupling common-gate （CG） topology to achieve wideband input matching and low noise figure （NF）. Inductive series-peaking is used for the LNA to obtain broadband flat gain in the whole 3.1-10.6 GHz band. Designed in 0.18 um CMOS technology, the LNA achieves an NF of 3.1-4.7 dB, an Sll of less than -10 dB, an S21 of 10.3 dB with ±0.4 dB fluctuation, and an input 3rd interception point （IIP3） of -5.1 dBm, while the current consumption is only 4.8 mA from a 1.8 V power supply. The chip area of the LNA is 1×0.94 mm^2.     

Effective Codelivery of lncRNA and pDNA by Pullulan‐Based Nanovectors for Promising Therapy of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers. Maternally expressed gene 3 (MEG3, one kind of long noncoding RNA [lncRNA]) can act as a tumor suppressor and regulate P53 target gene expression. However, lncRNA MEG3 demonstrates relatively low or no expression in human HCC. This study provides a promising concept to codeliver lncRNA and pDNA for cancer therapy. As proof‐of‐concept, the pcDNA‐MEG3 and pcDNA‐P53 plasmids‐condensed nanocomplexes with the liver‐targeting polycation gene vector, pullulan‐based ethanolamine‐modified poly(glycidyl methacrylate) (denoted as PuPGEA), are proposed to codeliver lncRNA and pDNA to treat HCC. Pullulan‐containing nanovectors are shown to be able to effectively mediate gene delivery in liver cells. To assess gene delivery performances of PuPGEA, a series of assays such as in vitro gene transfection, HCC cell proliferation, colony formation, migration, matrigel transwell assays, and in vivo xenograft animal models are carried out. The codelivery system with PuPGEA/(MEG3+P53) nanocomplexes demonstrates additive effects in suppressing HCC compared to PuPGEA/MEG3 or PuPGEA/P53 nanocomplexes alone. These results suggest that codelivery of lncRNA and pDNA by polycation nanovectors is a promising method to treat cancers.     

Compact hybrid master oscillator power amplifier with 3.1-W CW output power at wavelengths around 1061 nm

A hybrid master oscillator power amplifier (MOPA) laser source has been realized by coupling a single-mode three-section distributed Bragg reflector (DBR) laser as master oscillator and a tapered power amplifier with a single lens only. A maximum continuous-wave optical output power of 3.1 W was achieved. The emission spectrum was completely determined by the DBR laser. Single longitudinal mode operation at a wavelength of /spl lambda/=1061 nm was maintained over the whole power range. Up to an output power of 1.8 W, the beam propagation factor M/sup 2/was less than 1.6.     

Current-tuned GaAs Schottky-barrier Impatt diodes for 60?96 GHz operation

Oscillation of GaAs single-drift Schottky-barrier Impatt diodes mounted in a full-height IEC-R740 waveguide (3.1 × 1.55 mm2) has been observed between 60 and 96 GHz in pulsed operation. By bias-current tuning, a range of up to 19 GHz was covered with a single diode.     

掺杂与非掺杂相结合制备有机发光器件

采用掺杂和非掺杂方法制备了一种多层白色有机电致发光器件.DPVBi为蓝光发光层,将红光[Ir(piq)2(acac)]磷光掺杂染料掺入到母体BAlq中作为红光发光层,荧光材料QAD以亚单层的方式插入Alq3中作为绿光发光层,通过改变亚单层的厚度,得到了高效率的有机发光器件,此器件的最大电流效率可达6.1 cd/A,最大功率效率达3.1 lm/W,最大亮度达25 300 cd/m2,当电压从4V变化到14V时,色坐标从(0.45,0.55)变化到(0.47,0.37),处于黄白光区.此器件的特点在于器件的性能可以通过简单地调整QAD的厚度进行控制,避免了使用多掺杂层工艺的复杂性.     

Excellent effects of hydrogen postoxidation annealing on inversionchannel mobility of 4H-SiC MOSFET fabricated on (112¯0) face

Effects of hydrogen postoxidation annealing (H₂ POA) on 4H-silicon carbide (SiC) MOSFETs with wet gate oxide on the (112¯0) face have been investigated. As a result, an inversion channel mobility of 110 cm²/Vs was successfully achieved using H₂ POA at 800°C for 30 min. H₂ POA reduces the interface trap density by about one order of magnitude compared with that without H₂ POA, resulting in considerable improvement of the inversion channel mobility to 3.5 times higher than that without H₂ POA. In addition, 4H-SiC MOSFET with H₂ POA has a lower threshold voltage of 3.1 V and a wide gate voltage operation range in which the inversion channel mobility is more than 100 cm²/Vs     

An estimation and verification of vessel radar cross sections for high-frequency surface-wave radar

The radar cross sections of both small and large ships for high-frequency surface-wave radar (HFSWR) were studied by using the numerical electromagnetics code, and by using measurements from an HFSWR system at Cape Race, Newfoundland, Canada. The results of the study indicated that Teleost, a 2405-ton Canadian Coast Guard ship, and large cargo container vessels (-36000 ton) have comparable RCS values at 3.1 and 4.1 MHz. This was verified by comparing Teleost signals with the reflections of seven cargo-container vessels, identified during an operational evaluation of the HFSWR. The conclusion of the study was that Teleost and the large cargo container vessels had an angle-averaged radar cross section (RCS) of -40 dBm/sup 2/, while small vessels (-1000 tons) could reasonably be characterized by an angle-averaged RCS of -30 dBm/sup 2/, in the lower end of the HF band (3-5 MHz).