CD25分子胞外段基因免疫应答中B淋巴细胞的变化及意义

目的 用鼠CD25分子胞外段基因疫苗免疫Balb/c小鼠,观察其诱导的体液免疫应答中B淋巴细胞的变化并探讨其意义.方法 用pcDNA3.1-CD25胞外段真核表达质粒分别在第0天、第10天和第20天肌肉注射免疫同系Balb/c小鼠,酶联免疫法(ELISA)检测抗CD25胞外段的抗体水平及亚型,FACS检测脾细胞中B淋巴细胞的比例变化及细胞因子IL-4、IL-10和IFN-γ的表达变化.结果 与对照组相比,CD25胞外段基因免疫组小鼠血清抗CD25抗体在免疫后逐渐升高,第30天达最高峰;抗CD25抗体主要以IgG1为主;免疫小鼠脾细胞中B细胞的比例变化不显著(P>0.05),但高分泌IL-4和IL-10(P<0.05),而低分泌IFN-γ(P<0.05).结论 CD25胞外段蛋白基因免疫中B细胞功能变化显著,这为后续深入研究体液免疫应答在T细胞疫苗中的作用提供了前期实验基础.     

Saikosaponin D inhibits proliferation and induces apoptosis via C/EBPβ-p53 signal pathway in human hepatoma HepG2 cells

Objective To investigate the anticancer effects and detailed mechanisms of Saikosaponin D (SSD) in human hepatoma HepG2 cells. Methods Cell proliferation and apoptosis were tested by MTT assay and Annexin-V/PI assay respectively. The expressions of CCAAT enhancer binding protein β(C/EBPβ) and p53 were detected by RT-PCR and Western blotting. Results SSD inhibited cell proliferation in a dose-dependent manner and induced apoptosis at the concentration of 5.0mg/L. SSD significantly increased the mRNA and protein levels of C/EBPβ and p53 in a dose-dependent manner. Conclusion SSD exerts its anticancer effect by inhibiting cell proliferation and inducing apoptosis partly through C/EBPβ-p53 signal pathway in HepG2 cells.     

冰雪地区沥青路面抑制冻结铺装技术

提出一种节约环保型的冻结抑制路面,能够在一定程度上持续抑制路面冻结,减少融雪剂的撒布数量。提高机械除雪作业效率,节约冬季道路养护成本。这对于经济环保型路面除冰雪技术的研发具有重要的现实意义。     

环氧合酶-2介导四氢大麻酚抑制CA1区长时程抑制的作用

目的 探讨环氧合酶-2(cyclooxgense-2, COX-2)在四氢大麻酚(Δ~9-tetrahydrocannabinol, Δ~9-THC)抑制CA1区长时程抑制(lonG~-term depression, LTD)中的作用.方法 在小鼠腹腔注射Δ~9-THC(10 mg/kg)或COX-2的选择性抑制剂NS398(10 mg/kg)24 h后切片,在海马CA1区记录场电位EPSP(fEPSP),观察NS398和Δ~9-THC在LTD中的作用,并结合全细胞膜片钳技术观察THC对神经元膜兴奋性的影响.结果 ①给予低频电刺激(1Hz,15 min)诱导CA1区LTD,Δ~9-THC可显著降低LTD.②Δ~9-THC并不改变海马CA1区基本的突触传递和膜的基本电学特性(包括膜电位、输入阻抗及放电特性).③Δ~9-THC显著降低LTD的效应可被COX-2的选择性抑制剂NS398所反转.④在COX-2基因敲除的小鼠,Δ~9-THC降低LTD的作用被显著抑制.结论 在CA1区COX-2介导了Δ~9-THC降低LTD的作用.     

根除幽门螺杆菌对慢性胃炎和胃溃疡组织中MIF蛋白表达的影响

目的 通过检测幽门螺杆菌(Hp)感染及根除治疗对慢性胃炎和胃溃疡组织中巨噬细胞移动抑制因子(MIF)蛋白表达的影响,探讨MIF和Hp在慢性胃炎和胃溃疡发生发展中的作用.方法 胃镜下随机采集胃黏膜活检组织,经14C呼气试验、Warthin-starry银染色法检测Hp均为阳性,并经病理检验证实为浅表性胃炎、萎缩性胃炎、胃溃疡各40例,Hp阴性的健康检查者25例,采用免疫组织化学SP方法分别检测各组MIF蛋白的表达;进行Hp根治治疗2周,停药4周后复查Hp及MIF,比较根除前后各组MIF水平.结果 MIF蛋白在Hp阴性的正常胃黏膜中阳性表达低(2/25,8%);在Hp感染的慢性浅表性胃炎(12/40,30%)、萎缩性胃炎(26/40,65%)和胃溃疡组织(19/40,47.5%)阳性表达增强,显著高于Hp阴性的正常胃黏膜组(57/120 vs. 2/25;χ~2=13.376,P<0.01);在慢性炎症中,随着炎症程度增加,MIF表达增强,差异有显著性(12/40 vs. 26/40;χ~2=9.825,P<0.01);Hp根除后,MIF蛋白表达阳性率较治疗前显著降低(57/120 vs. 23/103;χ~2=15.264, P<0.01),而Hp仍为阳性者MIF蛋白阳性率无显著变化.结论 Hp感染导致的胃黏膜慢性炎症及溃疡的形成与胃黏膜MIF的表达相关,根除Hp感染可降低胃黏膜MIF基因表达的异常,可能对预防或减缓胃癌的发生和发展具有重要意义.     

An efficient and impartial online algorithm for kidney assignment network

An online algorithm balancing the efficiency and equity principles is proposed for the kidney resource assignment when only the current patient and resource information is known to the assignment network. In the algorithm, the assignment is made according to the priority, which is calculated according to the efficiency principle and the equity principle. The efficiency principle is concerned with the post-transplantation- immunity spending caused by the possible post-operation immunity rejection and patient's mental depression due to the HLA mismatch. The equity principle is concerned with three other factors, namely the treatment spending incurred starting from the day of registering with the kidney assignment network, the post-operation immunity spending and the negative effects of waiting for kidney resources on the clinical efficiency. The competitive analysis conducted through computer simulation indicates that the efficiency competitive ratio is between 6. 29 and 10. 43 and the equity competitive ratio is between 1. 31 and 5. 21, demonstrating that the online algorithm is of great significance in application.     

Code-aided interference suppression in direct sequence spread spectrum systems with eigenvector sign spreading code

For direct sequence spread spectrum (DSSS) communication systems suffering interference, it is known that code-aided interference suppression technique outperforms all of the previous linear or nonlinear methods. In this paper, we proposed an improved code-aided technique which can improve the system performance greatly by using the eigenvector sign (EVS) spreading sequence which depends on the statistical characteristics of the interference and the thermal noise. Foundation item: the National Natural Science Foundation of China (No. 60772100)     

化学类冻结抑制路面应用综述

冬季路面积雪结冰的处理是道路管理部门的难题。从沥青混合料中的特殊材料考虑,提出一种节约环保型的化学类冻结抑制路面,能够在一定程度上持续抑制路面冻结,减少融雪剂的撒布数量,提高机械除雪作业效率,节约冬季道路养护成本,这对于经济环保型路面除冰雪技术的研发具有重要的现实意义。     

基于遗传算法的分数阶PI~λD~μ控制器参数分级整定

针对交流电机振动抑制问题,提出基于遗传算法的分数阶PIλDμ控制器参数分级整定策略.通过遗传算法对整数阶PID控制器整定,获得一组控制参数;固定这组控制参数,再利用遗传算法对分数阶PIλDμ控制器进行阶次寻优.仿真结果表明,在PID控制器三系数不变的条件下,通过调整控制器的积分与微分阶次,分数阶PIλDμ控制器与整数阶PID控制器相比,动态性能指标均有所改善;所提出的分级整定策略对分数阶PIλDμ控制器参数确定是有效的.在不增加任何系统结构复杂性的前提下,改善了交流电机的振动抑制特性.