梯度法

Methods Density gradient centrifugalization combined with adherence method were used to segregate and cultivate rat MSCs. MSCs cultivated to the 3 rd passage were characterized using flow cytometry technique. TGF-β1 with 1, 2 and 5 μg/L were pretreated on MSCs for 8 h, then serum and oxygen deprivation were used to cause analogous ischemia of MSCs in vitro. AnnexinV/PI flow cytometry technique was used to evaluate apoptosis and survival of MSCs.

采用密度梯度离心结合贴壁法分离、培养大鼠MSCs，对培养第3代的MSCs进行鉴定；用1、2、5μg/L的TGF-β1分别预处理细胞8 h，然后用血清剥夺和低氧处理建立MSCs体外模拟缺血性损伤模型，通过流式细胞术评价MSCs的凋亡及存活情况；用Western blot方法检测2μg/L的TGF-β1对Akt和p-Akt表达的影响。

Methods Monocytes in peripheral blood were obtained from 12 patients with acute myocardial infarction, 16 unstable angina pectoris, 12 stable angina pectoris and 8 normals by ficoll density gradient centrifugalization. The cells were incubated for 48 hours to induce them to differentiate into macrophages by adding phorbolester 12-myristate 13-acetate. The levels of MMP-9 and TF in the supernatant were measured by ELISA.

密度梯度离心法提取12名急性心肌梗死、16名不稳定心绞痛、12名稳定型心绞痛患者和8名冠脉正常者的单核细胞，用佛波酯诱导其分化为巨噬细胞，ELISA法测定单核源巨噬细胞上清液MMP-9、TF含量。

By Percoll fluid and density gradient centrifugation,the MSC was obtained;after the cells filled the bottom of vessel,subcultured them,when they subculture in third generation ,redigested them,500 R/min centrifugate,alter the

经percoll液密度梯度离心法能获得纯度较高的人骨髓间充质干细胞，这种细胞在体外培养体系中保持旺盛的增殖能力；经轻度离心和化学限定培养基法可诱导骨髓间充质干细胞向成软骨方向分化，增殖旺盛，可传一代培养，是软骨组织工程理想的种子细胞。

MSC can be obtained by percoll fluid and density gradient centrifugation, this cells kept proliferation and differentiation ability in vitro; MSC can differentiate into chondroblast by lightly centrifugation and chemical definition medium, after one generation, the differential cells kept the phentype of chondroblast, they are a kind of ideal seed-cells for cartilage tissue engineering.

经percoll液密度梯度离心法能获得纯度较高的人骨髓间充质干细胞，这种细胞在体外培养体系中保持旺盛的增殖能力；经轻度离心和化学限定培养基法可诱导骨髓间充质干细胞向成软骨方向分化，增殖旺盛，可传一代培养，是软骨组织工程理想的种子细胞。

Objective To establish a new method for analyzing the contents of harpagoside and cinnamic acid in Xuanmaiganjie granula.

目的 用反相高效液相色谱梯度洗脱法测定玄麦甘桔颗粒中哈巴俄苷与肉桂酸的含量。

On the basis of experimental data, by the aid of boundary-element method, the temperature distribution, temperature gradient and colling velocity in the casting region ran be calculated.

本文建立了铝在双辊式铸轧时铸造区温度场的数学模型，根据实验数据用边界元法计算出铸造区的温度分布、温度梯度和冷却速度。

ABSTRACT With a Ni-base single crystal superalloy, DD8, a series of SC samples solidified with various solid-liquid interface morphologies planar, cellular, dendritical cellular, coarsely dendritic and fine dendritic ctc.

选用镍基单晶高温合金DD8为研究对象，利用籽晶法控制单晶的三维晶体取向，在自制高温高梯度LMC定向凝固装置上制取不同界面形态的单晶试样，首次系。。。

The digital closed-loop control system is designed and the dissolutive oxygen control algorithm is given out using neural PID algorithm.

设计了全数字化的闭环控制系统，以溶解氧指标为控制对象进行了控制算法设计，针对转刷曝气工艺的特点，采用神经PID调节算法，引入了线性神经元对经典PID算法进行优化、应用梯度下降法对NNC网络权值进行在线计算。

The digital closed-loop control system is designed and the dissolutive oxygen control algorithm is given out using neural PID algorithm. The traditional PID algorithm is optimized by neural network cell method and the weight value of NNC is generated on-line.

设计了全数字化的闭环控制系统，以溶解氧指标为控制对象进行了控制算法设计，针对转刷曝气工艺的特点，采用神经PID调节算法，引入了线性神经元对经典PID算法进行优化、应用梯度下降法对NNC网络权值进行在线计算。

Heterodon specimens was successfully extracted by the steps of removing the formaldehyde through improved gradual dehydration first and extracting the genomic DNA by the traditional phenol-chloroform method then. After primers designed, the PCR amplification was carried out, and a 205 bp of the control region of mtDNA from all of the ten specimens was successfully amplified.

本实验通过改进的酒精梯度浸泡法去除标本中的甲醛，然后用酚-氯仿抽提法成功地提取到了铜鱼标本的基因组DNA；设计引物后进行了线粒体和微卫星的PCR扩增，扩增产物经银染检测。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。