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101.
目的探讨胰腺癌组织周边和内部VEGF-C、VEGF-D蛋白表达与微淋巴管密度(microlymphtic vesseles density,MLVD)及淋巴结转移之间的相关关系,阐明癌周淋巴管增生的机制及意义。方法免疫组化检测30例胰腺癌组织周边和内部VEGF-C、VEGF-D、VEGFR-3(MLVD)蛋白的表达。结果肿瘤周边部位VEGF-C、VEGF-D蛋白阳性率分别为73.3%(22/30)、56.7%(17/30),显著高于肿瘤中心部位;在VEGF-C蛋白阳性组,MLVD显著高于阴性组(P<0.01),淋巴结转移发生率增高(P=0.0318);VEGF-D蛋白阳性组MLVD高于阴性组(P<0.01),淋巴结转移发生率增加(P=0.0179)。结论胰腺癌癌周VEGF-C、VEGF-D蛋白表达、MLVD显著高于肿瘤中心部位;癌周VEGF-C、VEGF-D蛋白表达、MLVD与淋巴结转移发生率呈正相关;提示VEGF-C和VEGF-D诱导胰腺癌癌周淋巴管生成,促进肿瘤细胞淋巴道转移。 相似文献
102.
The effects of external and internal tibial rotation on patellar motion were investigated using a magnetic 3Space® tracker system (Polhemus, Colchester, VT 05446, USA). Seven fresh-frozen adult cadaver knees were used in this study. The muscle alignment of each quadriceps muscle was measured to determine the direction of loading forces. Three loading patterns were used to simulate the unresisted knee extension during sitting, standing from squatting and the stance phase of walking, with different weights applied to each quadriceps muscle at each knee flexion angle. The position of the patella, along with patellar shift, tilt and rotation was measured and compared to external or internal tibial rotation and neutral rotation. In the sitting and squatting simulations the patella showed at the terminal extension of the knee more lateral shift and a more lateral tilt with tibial external rotation than in a neutral position (P < 0.05). In walking simulation, the patella showed more external rotation with external rotation of the tibia than with a neutral one, at the 0, 72 and 90% of the stance phase of walking (P < 0.05). These results demonstrate the importance of external tibial rotation as a factor in the development of patellar dislocations or subluxations, especially in athletes. 相似文献
103.
Saris DB Mukherjee N Berglund LJ Schultz FM An KN O'Driscoll SW 《Tissue engineering》2000,6(5):531-537
In biomedical research, agarose gel is widely used in tissue culture systems because it permits growing cells and tissues in a three-dimensional suspension. This is especially important in the application of tissue engineering concepts to cartilage repair because it supports the cartilage phenotype. Mechanical loading, especially compression, plays a fundamental role in the development and repair of cartilage. It would be advantageous to develop a system where cells and tissues could be subjected to compression so that their responses can be studied. There is currently no information on the pressure response of agarose gel when pressure is applied to the gas phase of a culture system. To understand the transmission of pressure through the gel, we set up an apparatus that would mimic an agarose suspension tissue culture system. This consisted of a sealed metal cylinder containing air as well as a layer of agarose submerged in culture medium. Pressure responses were recorded in the air, fluid, gel center, and gel periphery using various frequencies, pressures, gel volumes, and viscosities. Regression analyses show an almost perfect linear relation between gas and gel pressures (r(2) = 0.99987, p < 0.0001, f(x) = 0.9982 x - 0.0286). The pressure transmission was complete and immediate, throughout the range of the applied pressures, frequencies, volumes, and viscosities tested. Applying dynamic pressure to the gas phase results in reproducible pressure in the agarose and, therefore, validates the use of agarose tissue culture systems in studies employing dynamic pressurization in cartilage tissue engineering. 相似文献
104.
胶质瘤bcd—2基因表达水平与其细胞增殖和凋亡关系的研究 总被引:12,自引:0,他引:12
目的 探讨胶质瘤细胞bcl-2基因表达水平与肿瘤恶性程度、细胞增殖活性及凋亡程度的关系。方法 以69例不同级别的人胶质瘤组织为研究对象,用原位杂交及免疫组化染色ABC法分别检测bcl-2mRNA、bcl-2蛋白和增殖细胞核抗原(细胞增殖活性标记物)的表达,并用3’末标记法做原位细胞凋亡检测。结果 64例(92.8%)表达bcl-2mRNA,60例(87.0%)表达bcl-2蛋白,两者的表达水平呈正 相似文献
105.
重组人bFGF的原核表达及其高效价抗血清的制备 总被引:4,自引:1,他引:4
目的 以重组人碱性成纤维生长因子为免疫原,制备高效价抗hbFGF抗血清。方法通过PCR方法改造5’编码区的12个密码子,构建hbFGF’原核表达载体并在大肠杆菌(E.coli)中表达,以纯化的hbFGF、免疫新西兰兔,制备高效价抗血清,用于重组hbFGF、的免疫印迹分析。结果经过改造的hbFGF基因在E.coli中获得较高水平表达。从可溶性部分纯化得到纯度95%以上的重组hbFGF,以该重组蛋白免疫兔子,在二次加强后以间接ELISA检测抗血清效价可达1:512000。免疫印迹分析显示该抗血清与E.coli中表达的重组hbFGF、和标准hbFGF、均有特异性反应,但与某些细菌蛋白存在弱交叉反应,经E.coli菌体蛋白吸附的抗血清,与菌体蛋白的弱交叉反应消失。结论以纯化的重组hbFGF为免疫原制备了高效价的特异性抗血清,经菌体蛋白吸附可消除存在的交叉反应性。 相似文献
106.
Zhang Y MacLean JN An WF Lanning CC Harris-Warrick RM 《Journal of neurophysiology》2003,89(4):1902-1909
The transient potassium current (I(A)) plays an important role in shaping the firing properties of pyloric neurons in the stomatogastric ganglion (STG) of the spiny lobster, Panulirus interruptus. The shal gene encodes I(A) in pyloric neurons. However, when we over-expressed the lobster Shal protein by shal RNA injection into the pyloric dilator (PD) neuron, the increased I(A) had somewhat different properties from the endogenous I(A). The recently cloned K-channel interacting proteins (KChIPs) can modify vertebrate Kv4 channels in cloned cell lines. When we co-expressed hKChIP1 with lobster shal in Xenopus oocytes or lobster PD neurons, they produced A-currents resembling the endogenous I(A) in PD neurons; compared with currents evoked by shal alone, their voltage for half inactivation was depolarized, their kinetics of inactivation were slowed, and their recovery from inactivation was accelerated. We also co-expressed shal in PD neurons with lobster frequenin, which encodes a protein belonging to the same EF-hand family of Ca(2+) sensing proteins as hKChIP. Frequenin also restored most of properties of the shal-evoked currents to those of the endogenous A-currents, but the time course of recovery from inactivation was not corrected. These results suggest that lobster shal proteins normally interact with proteins in the KChIP/frequenin family to produce the transient potassium current in pyloric neurons. 相似文献
107.
Isaac M. Libermann Héctor Brazzuna Jorge Rodríguez Aníbal Capano Juanita Neumark 《Pflügers Archiv : European journal of physiology》1976,365(2-3):191-196
Summary Plasma volume, hematocrit, protein and electrolyte concentrations in plasma were measured in control and water-deprived rats every three days after starting the experiment until the 15th day. Plasma volume variations, as related to body weight, suggest that water loss from plasma was proportional to total body water at three days and after 9 days of water deprivation. Greater plasma water than body water loss was found during the period between 3 and 9 days. Plasma protein and electrolyte variations suggest that during water deprivation there is a loss of protein, sodium and potassium from plasma, which is proportionally less than that of plasma water. Potassium, calcium and inorganic phosphorus were lost proportionally to plasma water. The variations in plasma volume changes were partially explained as due to variations in plasma protein and electrolyte concentrations. 相似文献
108.
利用CT扫描及CAD技术建立腰椎活动节段的有限元模型 总被引:9,自引:0,他引:9
目的 :探讨腰椎活动节段有限元模型的建立。方法 :选取一正常自愿者L4~L5节段为研究对象 ,通过CT扫描、图像数字化处理及计算机辅助设计建立了腰椎活动节段的有限元模型 ,通过Super SAP有限元分析软件包对模型进行了应力分析。结果 :建立了L4~L5活动节段的有限元模型 ,并分析了生理载荷下腰椎活动节段不同组成部分的应力分布。结论 :为腰椎活动节段有限元模型的建立提供了一种简便、准确的方法 ,为分析和研究该模型在各种情况下的生物力学表现创造了条件 相似文献
109.
动态脑电图对缺血缺氧性昏迷病人的预后评估 总被引:4,自引:0,他引:4
目的:观察动态脑电图和临床检测指标对缺血缺氧性昏迷病人预后的评估价值。方法:在45例缺血缺氧性昏迷病人急性期进行动态脑电图检测和Glasgow评分、瞳孔对光反应、脑干反应检查,随访3个月时病人的预后,将动态脑电图检测和各项临床检查结果与病人的预后结果进行相关分析。结果:动态脑电图对昏迷病人预后的评估在敏感性(83.3%)、特异性(100%)和对预后评估的准确率(91.7%)方面均比临床检测结果高,临床指标Glasgow评分、瞳孔对光反射、脑干反射的敏感性、特异性及准确率分别为73.1%、84.2%及77.9%;76.9%、73.7%及75.6%;76.0%、68.4%及68.9%。结论:动态脑电图检测对急性缺血缺氧性昏迷病人预后的评估有确定的价值。 相似文献
110.
G An T H Huang J Tesfaigzi J Garcia-Heras D H Ledbetter D M Carlson R Wu 《American journal of respiratory cell and molecular biology》1992,7(1):104-111
An unusual expression of a putative squamous cell marker, small proline-rich protein (spr1), in mucociliary epithelial cells of conducting airways was demonstrated in a serum-free culture system. A cDNA clone was isolated from the cDNA library of monkey tracheobronchial epithelial (TBE) cells by differential hybridization. This cDNA clone, MT5, exhibited 98% homology to a DNA sequence obtained from human keratinocytes treated with either UV light or phorbol esters (T. Kartasova et al., 1988, Mol. Cell. Biol. 8:2195-2230). The predicted peptide of MT5 is unusual for its high content of proline (29%), glutamine (18%), and cysteine (9%) and its repeated PKVPEPC units. The level of spr1 mRNA in cultured cells was inhibited more than 90% by vitamin A. In contrast, phorbol 12-myristate 13-acetate (PMA) stimulated the level of spr1 mRNA by 3- to 8-fold. This differential regulation coincided with the effects of these chemicals on the cornification of cultured TBE cells. Using MT5 as a probe, we have localized the tracheal spr1 gene on the human chromosome 1 by a Southern blot analysis using a panel of human-rodent somatic cell hybrid DNAs. The gene was further sublocalized to bands q22-23 by in situ hybridization. 相似文献