作为信号的

ABSTRACT Hairy and Enhancer-of-split-type protein 1 (Hes1) is a main effecter of the Notch pathway and acts as a differentiation repressor and/or as a pro-expansion factor during the pancreatic development.

由于人们尚未找到胰腺干细胞的特异性标志，因而给胰腺干细胞的分离纯化及其特性的研究带来了极大的困难。来自hes1-/-敲除小鼠的研究提示，Hes1作为Notch信号通路的一个关键分子，在胰腺发育过程中扮演着扩增促进因子或分化抑制因子的角色，因而有可能用作胰腺干细胞的备选标志分子，但这一推论缺乏直接的证据。

These results suggest that the activate spleen-energy method can achieve appetitive purpose by not only affecting the gastrointestinal tract function in periphery, but also regulating the process of ingestion in brain. The basic research about ingestion indicate: one hand, after food enters the gastro-intestinal tract, the endocrine cell of the intestinal tract is activated and secrete many kinds of brains intestines peptide, the level of the brain intestines peptide in blood as the periphery signal spreads to the central nervous system regions that control digest and feeding behavior. On the other hand, it has been shown that dorsal parabranchial neurons, containing CCK-8S, extend fibers to the VMH and are involved in the inhibition of feeding .

关于摄食控制的基础研究表明，一方面食物进入胃肠道后，激活肠道的内分泌细胞，分泌多种脑肠肽如CCK-8S，这些脑肠肽在血中的水平作为外周信号可通过&肠—脑轴&传入中枢神经系统介导消化和摄食行为的部位，影响摄食中枢神经元的活动调节动物的摄食行为；另一方面中枢神经元可合成释放内源性的神经肽直接作用于摄食中枢神经元调节摄食，如中枢鳃旁体神经元的神经纤维就可延伸到达VMH，并且合成释放内源性的CCK-8S。

The article introduces some needed resolving problems. It brings forward principium of control, How can drive the servo signal and X and Z to the coordination of movements; How to change the feed rate; design of system structure, confirmation for input and output point, I / O address allocation;and also the project for speedup/down control during the screwthread processing. Method of programming design and manual operation trapeziform figure in system of numerical control lathe Corresponding project to problems is provided synchronously.

介绍可编程控制器应用于车床数控系统需要解决的问题，如何产生驱动伺服机构的信号及X、Z向的动作的协调；如何改变进给速度等；提出PLC作为数控机床主控制器的控制原理；系统结构设计；输入/输出点数确定及输入/输出点的地址分配；螺纹加工中升、降速的解决方案；程序设计及具体操作梯形图设计的方法，并给出相应的解决方案。

Furthermore, preliminary work also performed to examine whether PI3K/AKT signal transduction pathway was activated in the process of refractory leukemia development. Materials and methods An immortalized human bone marrow stromal cell line, HS-5, was introduced to establish a bi-phase culture system for the cultivation of B-lineage precursor leukemia cells. ELISA and RT-PCR were used to investigate the expression of VEGF and its receptors in the leukemia cell lines and primary childhood leukemia cells in different treated groups. Flow cytometory method and immunofluorescent staining were employed to examine the apoptosis signals both in the VP16 treated and untreated leukemia cells. Western blot was utilized to explore the PI3K/AKT activated status in the drug induced or uninduced leukemia cells and lymphocytes from healthy donors.

材料和方法使用来源于人类骨髓基质细胞的细胞株HS-5作为滋养层细胞进行急性淋巴细胞性白血病细胞的体外培养，通过细胞生物学和免疫学方法评估培养体系并鉴定出难治性白血病细胞克隆；以ELISA和RT-PCR方法检测急性白血病细胞株和患儿白血病细胞VEGF及其受体的表达，了解不同治疗阶段VEGF及其受体的表达状况，并结合临床指标进行分析，明确VEGF及其受体在白血病发生过程中的作用；流式细胞仪和免疫荧光染色法对正常健康儿童、初发白血病患儿、复发白血病患儿及缓解后患儿进行凋亡因子检测和分析，初步阐明难治性白血病抗凋亡形成的原因；蛋白印记分析检测PI3K/AKT信号传导通路在健康儿童、初发白血病和复发白血病患儿的表达，初步了解难治性白血病形成的分子生物学机制。

In summary, the BRD7 gene acted as a candidate of tumor suppressor gene with NPC. The overexpression of BRD7 can partly reverse malignant phenotype of NPC cell line. The suppression effect of BRD7 on NPC tumorigenesis my be achieved by recognizing acetylated histone peptide through their motif-bromodomain, then modulating gene transcription by taking part in histone acetylating and chromosome remodeling, finally influencing signal-transduction pathways.

综上所述，BRD7基因作为一个重要的鼻咽癌抑瘤基因侯选者，在鼻咽癌细胞中的过表达后，可导致鼻咽癌细胞 HNE蛋白质表达谱发生改变，逆转其恶性表型，其作用机理可能是：BRD7基因通过其功能域彭聪硕士学位论文10Bromodomain与乙酚化的组蛋白特异性结合，参于染色体的乙酚化，染色质的组装，从而影响基因转录的调控，最终影响细胞内的信号传导通路并实现对细胞周期的调控，从而发挥抑制鼻咽癌细胞生长的作用。

Based on the theory of frequency modulation,the principle that frequency jittering spreads the spectrum energy of the voltage and current is analyzed.

针对传统的固定频率PWM控制方式引起的波形频谱能量集中、谐波幅值较大的缺点，文章基于频率调制的理论分析了开关频率抖动技术扩散电压频谱以及电流频谱能量的基本原理，结合传统的PWM控制器，采用三角波作为调制信号实现简单的频率抖动的方法。

When content of Nicotine increased, protein decreased in leaf and root of toped tobacco. This probably because the content of IAA decreased rapidly and acted as the first signal to transfer to root in toped tobacco, and this made the second signal 桝BA and ZR increased, activated biosynthsis of Nicotine.

打顶以后烟碱含量增加的同时，叶和根中的蛋白氮含量均降低，还原糖含量增加，这可能是由于打顶以后，IAA的迅速降低作为第一信号，沿木质部向下运输到根，引起根部的第二信使一ABA、ZR等含量的增加及GA；含量的减少，激活烟碱合成的三种酶，使总氮中用于合成蛋白质的氮减少，自由氨基酸增加，促进烟碱的合成。

In order to overcome those limitations, and on the premise that the receiver can measure the pseudo-range between the user and satellite and with the help of barometer, this paper put forward the pseudo-range integration model of RDSS and the strap-down inertial navigation system with high precision clock, rubidium clock being the internal clock of the RDSS receiver.

基于北斗双星定位系统采用有源定位体制存在一定的局限性，在接收机能够测量用户至卫星的伪距信号以及在气压高度表辅助的前提下，提出了利用铷钟作为接收机内部时钟的RDSS与捷联惯导进行伪距组合的模型，建立其卡尔曼滤波的状态方程与量测方程。

After analyzing the performance anduncertainty of the DDPM vortex flowmeter in gas-liquid bubble flows, the vortexflowmeter-Venturi tube combinative method using the vortex flowmeter and the Venturi tube as measuring cells was put forward, the measurement model based on thevortex frequency and the Venturi differential pressure was established, and it showsthat the relative errors of this method for the mass flow measurement of bubble flowsare within±5%. Furthermore, the flowrate and volume void fraction of bubble flowswere obtained using a single DDPM vortex flowmeter through the relationshipbetween the frequency and amplitude of the circumferential DDPM signal, and resultsdemonstrate that the relative errors of the flowrate and volume void fraction of bubbleflows are within±5% and±10% respectively, which indicates the broad applicabilityof this method to large numbers of engineering fields.

通过分析管壁差压式涡街流量计在气液泡状流中的性能和不确定度，提出了以涡街流量计和文丘里管作为测量元件的&涡街—文丘里联合法&，建立了以涡街频率和文丘里差压为被测量的测量模型，该方法对气液泡状流质量流量的测量相对误差可达±5％；通过建立涡街周向管壁差压信号频率和幅度与被测流体的关系，使用单个涡街流量计实现了对气液泡状流流量和体积含气率的双参数测量，该方法对气液泡状流流量和体积含气率的测量相对误差分别为±5％和±10％，可以满足大量工业实际应用的要求。

The wavelength resolution of the sensing measurement is 0.05nm. A novel FBG Bourdon tube sensor has been constructed, utilizing the pressure mechanic amplify function of Bourdon tube. The measured pressure sensitivity is two orders of magnitude higher than a simple monomode fiber with an in-fiber grating. Especially the pressure sensitivity of the sensor can be determined by changing the parameters of the cantilever beam. Adopting polymer package technique, we coat fiber Bragg grating by using polymer with different mechanic properties. Due to the driving effect of the polymer substrate, the enhanced pressure sensitivity is more than 20 times and 31. 7 times than that of a bare fiber grating. The packaged grating exhibits no significant chirp due to the adoption of special packaging technique.

全部采用国产元器件，成功地研制了掺铒光纤超荧光宽带光源，并将其组装成仪器；设计了利用可调谐FBG滤波器对光纤光栅传感信号进行检测的实验方案，对这一传感检测方案进行了理论分析和实验研究，由于采用了高性能的光电测量系统，传感测量的波长分辨率可达2pm，对应的应变分辨率为1.7με，在此基础上对FBG的波分复用传感特性进行了研究；对比调谐滤波检测技术，对光纤光栅可调谐光源波长检测技术进行了理论分析；采用长周期光纤光栅作为边带滤波器，对光纤布拉格光栅的传感信息进行解调，设计了一种全光纤传感测试系统，其波长分辨率可达0.05nm。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。