KDR基因遗传变异对贝伐珠单抗一线治疗晚期非小细胞肺癌患者临床疗效的影响

目的: 本研究旨在探讨激酶插入区受体（KDR）基因遗传变异对贝伐珠单抗联合化疗治疗晚期非小细胞肺癌（NSCLC）患者疗效的影响。方法:本研究纳入135例一线接受贝伐珠单抗治疗的NSCLC患者,收集外周血及活检癌组织标本分别用来进行基因分型及表达测定。多态性位点的基因型和其他变量的相关性通过logistic回归模型进行分析。基因型和预后的单变量分析用Kaplan-Meier生存分析方法,并通过Cox风险比例模型对其他变量进行校正。结果:在KDR的标记多态性位点中,只发现了V297I位点的临床意义。V297I位点位于该基因的编码区,在研究人群的基因分布频率为：CC型99例（73.33%）,CT型33例（24.44%）,TT型3例（2.23%）,最小等位基因频率为0.14,三种基因型分布频率符合哈迪温伯格平衡（P=0.898）。后期比较将TT型和CT型患者合并,对不同基因型患者进行疗效分析发现：CT/TT基因型患者和野生型CC型患者的客观缓解率（ORR）分别为41.67%和47.47%（P=0.549）。CT/TT和CC基因型患者的中位无进展生存期（mPFS）分别为6.2和8.6个月,差异具有统计学意义（P=0.003）。在总生存期（OS）方面,两种基因型患者的中位总生存期（mOS）分别为18.9和21.5个月,差异具有统计学意义（P=0.017）。对无进展生存期（PFS）构建多变量的Cox模型校正之后发现CT/TT基因型对PFS的影响仍然具有统计学意义（OR=1.95,P=0.019）。另外,进一步在68例癌组织标本的表达分析中发现,CT/TT基因型患者相对于野生型的CC型患者,癌组织中KDR的表达明显较高,且差异具有统计学意义（P<0.01）。结论:在接受贝伐珠单抗治疗的非小细胞肺癌患者中,KDR基因V297I位点可能通过影响KDR基因的表达从而影响贝伐珠单抗一线治疗非小细胞肺癌患者的疗效。     

Fabrication and tribological behaviors of corner-cube-like dimple arrays produced by laser surface texturing on medical needles

Micro-corner-cube-like dimples with various geometrical characteristics were fabricated on the surface of medical needles by laser surface texturing. The effects of geometric parameters of dimples on tribological behaviors were investigated by carrying out insertion tests. It was found that the textured surface with a dimple array increased the friction between the needle and phantom tissue because of stress concentrations near the edges. Furthermore, the drag increment rate increased with the increase of dimple size and circumferential number, while dimple depth had no significant effect on the friction. The minimal drag increment rate was achieved at a medium value of spacing. The geometric parameters of dimples could be varied to control area density that indirectly affect the friction behavior.     

The enhancing effect of surface coatings on cast-in bonding of steel and titanium inserts in aluminium castings

Insertion bonding of mild steel and titanium pipes in aluminium castings was performed in two ways; either by holding paired pipe and aluminium cylinder specimens at constant high temperatures, or by pouring molten aluminium into sand moulds containing inserts. The surfaces of the inserts were electroplated using Ag or Au, or spray coated with Al-Si alloy. The bonding was evaluated by shear strength measurements and microstructure observations. To verify the effect of surface coatings, the contact between the molten aluminium and the specimens was observed. At constant high temperatures, coated steels showed good metallurgical bonding when they were maintained for about 200 s in contact with molten aluminium. The time necessary for bonding was shorter with titanium inserts. In bonded specimens, alloyed microstructures were observed at the interfaces. There was no bonding with uncoated specimens. All coatings used were effective when poured, but preheating of the moulds was necessary to allow sufficient solidification time for the melt/insert volume ratios which were 32 and 36. Process analysis by the finite difference method showed that bonding required a period of liquid phase contact of the melt with the inserts. Observation of aluminium droplet contact with the inserts showed that uncoated surfaces of steel and titanium are not wetted by the melt due to stable oxide skins. With Ag electroplating, aluminium droplets can make wet contact with the specimens. The contact angle decreased from about 140° in uncoated specimens to 15°-45° with Ag plating. The plating prevents surface oxidation of the inserts and promotes wet contact when the active aluminium liquid surface is exposed. The Al-Si alloy spray coating has some effect in promoting wettability, but it is inferior to Ag plating.     

低车流量下高速公路声屏障插入损失的分析计算

在对车流量较低的高速公路声屏障进行声学测量时，发现声屏障的实际降噪效果低于传统理论计算值。分析了车流量对这种偏差影响的原因，提出了等效时间模型和利用无限长线声源、有限长声屏障绕射损失计算公式进行修正的方法。     

BNKLT无铅压电陶瓷中频滤波器的研制

采用本组发明的[Bi0.5(Na1-x-yKxLiy)0.5]TiO3(BNKLT)系无铅压电陶瓷,研制了单片式中频陶瓷滤波器。该体系陶瓷具有较高的使用温度,在160℃以上仍具有较强压电性。利用此体系材料,采用轮廓振动模式,制作了插损约为3 dB,中心频率约为530 kHz,带宽约为8.8 kHz,左、右选择性均良好的无铅压电陶瓷单片式中频滤波器。除中心频率以外,各项指标均与村田公司同类含铅陶瓷中频滤波器(SFU系列)产品相当,具有良好的应用前景。     

MEMS开关封装结构热形变对芯片性能的影响

模拟了处在一定功率密度或不同温度下封装结构贴片的形变引起的X波段MEMS开关芯片的形变,从而导致的开关芯片性能的变化。用Coventor软件模拟出在开关衬底为200μm,贴片处功率密度为300pW/μm2时,开关芯片的形变量为0.142μm;开关衬底为300μm,温度为373K时,开关芯片的形变量为0.791μm。进一步用HFSS模拟出开关的插入损耗在中心频率10GHz处由封装前的0.042dB和0.022dB变化为封装后的0.078dB和0.024dB。     

宽带七端口铁氧体环行器组件的研制

介绍了一种新型的宽带x波段七端口环行器组件，当信号从输入端输入时可分成若干个分支信道输出，组件的总插入损耗（6个信道）≤3.5Db，各输出信道之间的反向损耗α_≥30Db，可用于频率变换技术。     

A per-object-granularity tracking mechanism and systemfor interactive TV viewership estimation and program rating in real time

TV program ratings directly affect the decisions of advertisers and TV stations program offerings. TV program providers use television ratings reports to offer appropriate programs as well as attract advertisers. In this paper we propose a framework for TV audience estimates and program ratings using a per-object-granularity tracking mechanism for interactive TV content tracking in real time. It can be applied to live TV broadcasting environments as well as recorded broadcasting environments. The major components of the proposed tracking architecture are an interactive TV content creation tool powered by hotlinked video technology, a tracking information delivery framework with live interactive content insertion capability, an interactive TV content receiver, and tracking servers. The proposed mechanism and system in this paper enables a broadcast station or a rating agency to automatically perform tracking functions in real time based on viewer actions as well as on the content of audiovisual programming.     

单个MZI型DQPSK解调器的设计与仿真

文章采用91 μm厚的石英半波片来降低器件的PDFS(偏振相关频率漂移),在放置半波片位置采用优化的楔形波导结构,将插入半波片带来的附加损耗降至0.41 dB.并通过广角三维光束传输法,对DQPSK(差分正交相移键控)解调器在C波段进行了仿真.结果表明:采用这种结构设计出的器件具有低插损值和高消光比.     

视频转换编码的快速图标插入技术研究

数字视频转换编码技术为传输带宽匹配等问题提供解决方案,在许多具体应用中,要求在转换编码时在视频图像中加入图形标识,本文对转换编码中图标插入技术进行了分析和研究,给出了一种快速图标插入转换编码技术,提出了图标插入后运动矢量及宏块模式判别等问题的优化算法,实验结果表明,使用本算法进行图标插入的转换编码流质量良好.