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1.
WANG Hong WU Jin-min CAO Hou-jun ZHOU Wen-peng FANG Yong ZHANG Xing ZHENG Shu 《园艺学报》2006,22(6):1218-1221
AIM:To evaluate the relationship between u PA and NF-κB p65 expression and its clinical significance in breast cancer.METHODS:The uPA mRNA was measured by real-time fluorescent quan t itative PCR in 46 cases of breast cancer tissues and their adjacent counterparts .NF-κB p65 were measured using immunohistochemistry.RESULTS:The expression of uPA gene was elevated in 63% of cases ,and there was a strong correlation between NF-κB p65 and uPA expression (r =0.451,P<0.01).In addition,the expression of uPA was associated with num bers of axillary lymph node involvement and tumor size.However,no significance was found in uPA expression in the age,pathological type and distant metastasi s organ classification.CONCLUSION:The uPA gene is highly expressed in most of the brea st cancer,and there is strong correlation to NF-κB p65 expression,number of l ymph nodes involvement and tumor size. 相似文献
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AIM: To study the effect of interleukin 18 gene transfected lung cancer cells on the phenotype and immunological activity of dendritic cells (DC). METHODS: A secretive IL-18 expression vector containing IL-12 P40 signal sequence was constructed and transfected into NCI-H460 lung cancer cells. DC induced from human peripheral blood were divided into 4 groups (NT, PV, GT and PD). DC were stimulated by non-transfected NCI-H460 cells, pure vector transfected NCI-H460 cells and IL-18 transfected NCI-H460 cells respectively for group NT, PV, GT, and non-stimulated DC for group PD. CD54, CD80, CD83 and CD86 on DC in the 4 groups were detected with flow cytometry. T cell proliferation stimulated by DC in the 4 groups was assayed with MTT method. IL-12 release in cultured DC supernatant was measured by ELISA. RESULTS: Sequencing result of the secretive IL-18 was correct. The transfected cells expressed IL-18 fusion gene and 18 kD IL-18 protein. DC in GT group expressed more surface molecules than those in other 3 groups. T cell proliferation and IL-12 secretion in GT group were higher than those in other 3 groups. CONCLUSION: IL-18 gene transfected NCI-H460 cell increases surface molecule expressions on DC. It also enhances immunological activity and IL-12 secretion in DC. 相似文献
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AIM:To investigate the role of caspase 3 inhibitor Ac-DEVD-CHO in caspase 3 signaling pathway and NF-κB activation induced by 10-hydroxycamptothecin (HCPT) in human breast carcinoma cells. METHODS:The cell growth inhibition was measured by MTT assay. Agarose gel electrophoresis was performed for detecting cell apoptosis. Western blotting was used for determining protein expression. DIG-EMSA was conducted to measure the DNA-binding activation of NF-κB. RESULTS:Caspase 3 inhibitor Ac-DEVD-CHO attenuated HCPT-induced apoptosis in human breast carcinoma. Ac-DEVD-CHO also suppressed the degradation of caspase 3 and IκBα,and arrested the activation of NF-κB. CONCLUSION:Caspase 3 inhibitor Ac-DEVD-CHO regulates the activation of caspase 3 and NF-κB,and attenuates apoptosis in Bcap37 cell line induced by HCPT. 相似文献
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基于最小二乘支持向量机的人民胜利渠灌区灌溉用水量预测 总被引:3,自引:0,他引:3
基于最小二乘支持向量机(LSSVM)良好的泛化能力和特点,以人民胜利渠灌区需水量为研究对象,选用径向基函数(RBF)作为核函数,建立了最小二乘支持向量机预测模型,对灌区需水量进行了模拟计算,用检验样本与灰色预测和基于RBF的神经网络模型的预测结果进行了比较,LSSVM预测的最大误差8.78%,平均误差4.90%。结果表明最小二乘支持向量机模型有较高的预测精度和较强的泛化能力,可为灌区水资源规划提供科学依据。 相似文献
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水氮状态的准确估计对于作物生长模拟和产量估计十分重要.数据同化可以集成观测和模型,从而实现更加准确的模拟.然而,传统的数据同化系统大多关注叶面积指数(LAI)、土壤含水量(SM),对于氮素状态估计的研究相对较少,缺乏水氮数据联合驱动的数据同化研究.采用集合卡尔曼滤波(EnKF)方法对SWAP-WOFOST模型构建冬小麦生长的数据同化系统,通过引入叶片氮累积量(LNA)的观测,同时更新SM、LAI、LNA和作物产量等关键状态变量后进行作物生长模拟.结果表明,只加入LAI和SM可以很好更新模型的土壤水分剖面和LAI,但是对于LNA和产量的模拟效果不佳;加入LNA观测后,有效提高了作物LAI、LNA和产量的模拟精度.同时更新模型状态和参数(SSPE)比只更新状态(USO)的模拟效果更好,尤其是在土壤含水量的估计中.无论是水分还是氮素状态模拟出现偏差的情况,都很难准确估计最终的作物产量,而水氮数据联合驱动的结果最优.此外,研究中的数据同化系统在不同观测误差和观测频率下都具有良好的稳健性.该研究有助于深入理解冬小麦生长与水氮状态的关系,对实际应用中的作物生长模拟和产量估计具有一定指导意义. 相似文献
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The prefabricated pile,driven in soft clay,can squeeze the soil laterally in a certain scope around the pile,and the void ratio is reduced significantly;consequently,the shear bearing capacity is raised.But the soil parameter,which is used to estimate the capacity of pile,is reduced according to the soil state before the pile was driven.Then,a certain difference appears when the pile is working.The calculation result usually is partial to conservative.This paper analyzes the squeezing mechanism of the pile using the theory of cylindrical cavities expansion.And a formula,which is used to estimate the increment of shear bearing capacity of soil around the pile when excess pore water pressure from pile driving distributes completely,is presented based on the unique relation between the shear bearing capacity and the density of the soil.This formula can be used to estimate the final ultimate-bearing capacity of the pile.The calculated results by the proposed formula are in good agreement with those of the site measurement. 相似文献
10.
在江淮丘陵地区首次较大规模引进薄壳山核桃的育苗过程中,为提高引种成功率和苗木生长量,在种子处理、土壤改良和苗期管理等方面采取了不同的技术措施,并分析不同处理因素对苗高、地径、树冠生长及成苗率的影响。初步研究结果表明:在粘盘黄棕壤为主的江淮丘陵地区,可以进行薄壳山核桃引种育苗;土壤改良有利于提高苗木生长量;间隔不长的不同播种时间对苗木生长没有显著影响;同批次的大粒种子生长量比小粒种子大。 相似文献