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71.
用EBV LMP2A重组痘苗病毒 (rVV LMP2A )转染人树突状细胞 (DC ) ,转染后的DC分别在第 1、 7、 14天刺激相同MHC背景的T细胞 ,在IL 2作用下诱导LMP2A特异性CTL。用LDH释放法检测CTL杀伤活性 ;流式细胞术 (FACS )检测CTL诱导分化过程中CD3+ 、CD4 + 、CD8+ 、CD5 6 + 等细胞的分群变化 ;RT PCR检测细胞分化过程中FasLmRNA表达 ;生物活性法检测功能性细胞因子IFN γ的分泌。结果显示本法诱导的CTL对靶细胞有特异性杀伤活性 ,第 2次和第 3次DC刺激后杀伤活性有所上升 ;在CTL诱导分化的第 7、 14、 2 1天细胞分群以CD4 + 、CD8+ 细胞为主 ;RT PCR证实所诱导的细胞内有FasLmRNA的表达 ;随细胞培养天数的增加IFN γ分泌增加 ,在第 14天达到较高水平。研究表明重组痘苗病毒载体rVV LMP2A转染的DC刺激T细胞可诱导出EBV LMP2A特异性CTL。 相似文献
72.
目的探讨脑卒中癫痫的,I岳床特点及发病机制。方法对1000例脑卒中患者中60例继发性癫痫患者的临床资料进行回顾性分析。结果脑卒中癫痫的总发生率6.00%,卒中后早期癫痫的发生率为53.33%(32/60),晚期发生率为46.67%(28/60),以部分发作为最多占65.00%(39/60),卒中后癫痫的发生率与病灶部位有关,皮质病灶较易发生卒中后癫痫,皮质(10.65%)与皮层下(2.73%)比较差异有显著意义(P〈0.05),而不同卒中类型癫痫发生率差异无显著意义(P〉0.05)。结论脑卒中是老年人癫痫发作的最常见原因,皮层病灶较易发生癫痫。 相似文献
73.
Proximal tubular epithelial cell integrins respond to high glucose by altered cell-matrix interactions and differentially regulate matrixin expression 总被引:11,自引:0,他引:11
Karamessinis PM Tzinia AK Kitsiou PV Stetler-Stevenson WG Michael AF Fan WW Zhou B Margaritis LH Tsilibary EC 《Laboratory investigation; a journal of technical methods and pathology》2002,82(8):1081-1093
Thickening of the tubular basement membrane (TBM) occurs in diabetic nephropathy, but the effects of high glucose on the functional aspects of proximal tubular epithelial cells are not clearly understood. In the present study, we examined the effects of elevated glucose concentrations on (a) integrin expression by human proximal tubular epithelial cells (HK-2) and integrin-mediated interactions with type IV collagen (colIV) and laminin, major components of TBM; (b) the expression of matrixins/matrix metalloproteinases (MMPs), which is regulated by integrins; and (c) the expression of tissue inhibitors of metalloproteinases (TIMPs). HK-2 cells cultured in 25 mM glucose underwent a reduction of the expression of alpha3, beta1, alpha(v)beta3, and alpha5 integrin subunits, with a concomitant increase of the alpha2 subunit, compared with cells grown in 5 mM glucose. Adhesion experiments demonstrated that high glucose led to increased cell adhesion on either colIV or laminin. Experiments of competition of adhesion using anti-integrin antibodies indicated that HK-2 cells in 5 mM glucose used mainly alpha(v)beta3 and alpha5beta1 integrins to adhere to colIV, whereas in 25 mM glucose they additionally used alpha2beta1. In the case of laminin, a beta1-mediated adhesion was observed when HK-2 cells were in 5 mM glucose, whereas in 25 mM glucose, alpha2beta1 and alpha(v)beta3 were also involved. Elevated glucose concentrations resulted in decreased expression of MMP-9 and MMP-2, whereas an increase in TIMP-1 and a decrease in TIMP-2 expression were observed. We also examined which integrins mediated the expression and secretion of matrixins MMP-2 and MMP-9. Ligation of alpha3beta1 with mAbs resulted in induction of MMP-2 expression and secretion, whereas antibody ligation of alpha(v)beta3 led to down-regulation of MMP-9. The above data implicate integrins of proximal tubular epithelial cells in the regulation of MMPs and in the development of TBM thickening in diabetic nephropathy. 相似文献
74.
目的探索Opa相互作用蛋白5(OIP5)在胰腺癌中的表达及其对PANC-1细胞增殖的影响。方法通过数据库分析OIP5在胰腺癌组织及癌旁组织中的表达;用实时定量PCR(RT-qPCR)和蛋白印迹法(Western blot)分别检测人胰腺癌细胞系MIAPaCa-2、PANC-1、KP-3、BxPC-3细胞中OIP5 mRNA和蛋白表达;构建OIP5基因沉默质粒的慢病毒(pGCSIL-shOIP5)和对照质粒慢病毒(pGCSIL-shCtrl),分别感染PANC-1细胞,分为OIP5基因沉默组和shCtrl对照组,5 d后采用RT-qPCR和Western blot测定慢病毒敲低效率,流式细胞计量术检测细胞凋亡;OIP5基因沉默组和shCtrl对照组连续5 d进行MTT检测和细胞计数;OIP5基因沉默组和shCtrl对照组孵育10 d形成集落,Giemsa染色分别集落总数。结果胰腺癌中OIP5 mRNA表达显著高于正常胰腺组织(P<0.05),OIP5高表达患者的总存活率显著低于OIP5低表达患者(P<0.05),且其无病生存率也显著降低(P<0.05);OIP5在MIAPaCa-2、PANC-1和KP-3中表达较高,而在BxPC-3细胞系中的表达较低;MTT检测结果显示OIP5沉默在第4和第5天显著降低了PANC-1细胞的增殖速率(P<0.01);OIP5沉默后细胞集落数(平均为9个)显著低于shCtrl对照组中的数量(平均为40个)(P<0.01);OIP5沉默后PANC-1细胞凋亡比例为8.3%显著高于shCtrl的4.5%(P<0.01)。结论OIP5在胰腺癌细胞系中异常高表达,OIP5基因可调控胰腺癌PANC-1细胞的增殖、凋亡以及集落形成,提示OIP5可能在胰腺癌发病机制中作为癌基因发挥作用,从而为胰腺癌的靶向治疗提供了潜在的生物标志物。 相似文献
75.
耳穴电参数时变关系实验表明,在测量起始t<2τ时,因瞬变作用,电位E(t)和压降U(t)为瞬态响应,响应函数呈指数关系,特征参数为弛豫时间τ,τ≈RC;t>2τ时,为时变间期。电路分析给出数学描述,并与耳穴和模拟实验结果较相符。提示,时变特征应以t>2τ后提取,静态电测量时,采样应避开瞬变期,可提高准确性。该工作对正确鉴别时变性和特征提取,全面认识耳穴电特性具有重要意义。 相似文献
76.
Han Lü Sixun Zheng Bing Zhang Xiaozhen Tang 《Macromolecular chemistry and physics.》2004,205(6):834-842
Summary: The blends of poly(hydroxyether sulfone) (PHES) with poly(N‐vinylpyrrolidone) (PVPy) were investigated by means of differential scanning calorimetry (DSC) and FTIR spectroscopy. The miscibility of the blend system was established on the basis of the thermal analysis results. DSC showed that the PHES/PVPy blends prepared by casting from N,N‐dimethylformamide (DMF) possessed single, composition‐dependent glass transition temperatures, indicating that the blends are miscible in the entire composition. The experimental glass transition temperatures have higher values than those calculated on the basis of additive behavior; the variation of the glass transition temperatures of the blends was accounted for by the Kwei equation. FTIR studies indicate that competitive hydrogen bonding interactions exist upon addition of PVPy to the system, which were involved in the self‐ and cross‐association, i.e., ? OH···O?S, ? OH···OH of PHES and ? OH···O?C< of PVPy. The FTIR spectra in the range of the sulfonyl stretching vibrations showed that the hydroxyl‐associated sulfonyl groups are partially “set free” upon addition of PVPy to the system. The IR spectroscopic investigation of both the model compounds and the PHES/PVPy blends suggests that the strength of the hydrogen bonding interactions in the blend system increases in the following order: ? OH···O?S, ? OH···OH and ? OH···O?C<.
77.
对于科学研究工作来说,时间分辨率和空间分辨率都是十分重要的,在设计相应的图像处理系统时必须两者兼顾。对于生命科学及工业等领域而言,希望图像处理系统不仅有较高的时间分辨率,还要有较高的空间分辨率。本文提出一种利用多部CCD数码相机、采用移相法获取高分辨牢和高摄录帧率的技术,此技术可应用于普通CCD数码相机组成的复合摄录系统。 相似文献
78.
Encoding of electrical, thermal, and mechanical noxious stimuli by subnucleus reticularis dorsalis neurons in the rat medulla 总被引:2,自引:0,他引:2
1. In anesthetized rats, recordings were made within the medullary subnucleus reticularis dorsalis (SRD) from neurons that exhibited convergence of nociceptive inputs from the entire body. Neurons with total nociceptive convergence (TNC) responded to suprathreshold percutaneous electrical stimuli (2-ms duration) with an early and a late peak due to activation of A delta- and C-fibers, respectively, no matter which part of the body was stimulated. Neurons with partial nociceptive convergence (PNC) responded to the same stimuli with an A delta-peak regardless of which part of the body was stimulated and with a C-peak of activation from some, mainly contralateral, parts of the body. The characteristics of the responses of these neurons to the application of graded intensities of electrical, thermal, and mechanical stimuli were analyzed. 2. All TNC neurons and 85% of PNC neurons responded to A delta- and C-fiber activation following percutaneous electrical stimulation of the contralateral hindpaw. With regard to A delta-fiber-evoked responses, a linear relationship between the logarithm of the applied current and the magnitude of the responses was found within the 0.25- to 6.0-mA and 0.5- to 24-mA ranges for TNC and PNC neurons, respectively; however, these curves were essentially similar. With regard to C-fiber-evoked responses, such a linear relationship was found within the 1.5- to 6.0-mA range for both types of SRD neurons, although the TNC neurons presented larger C-fiber-evoked responses than did the PNC neurons. 3. TNC and PNC neurons linearly increased their discharges during the application of noxious thermal stimuli to the contralateral hindpaw within the range 44-52 degrees C; the mean responses evoked by noxious heat from TNC neurons were of higher magnitude than those from PNC neurons. The majority of SRD neurons presented long-lasting afterdischarges, especially with the highest temperature employed (52 degrees C). 4. TNC neurons monotonically increased their discharges during graded mechanical or thermal stimulation of the tail. When mechanical stimuli were applied, a linear relationship was found between the logarithm of the strength of the mechanical stimulus and the neuronal discharges, in the 5.3- to 7.4-N/cm2 range. With thermal stimulation, TNC neurons linearly increased their discharges in the 44-52 degrees C range. When increasing amounts of the tail were immersed in a 50 degrees C waterbath, TNC neurons increased their discharges within a restricted range of tail surface areas (0.9-5.7 cm2); further increases in the stimulated surface size were not followed by increases in firing rate.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
79.
Four-Dimensional Computerized Tomography (4D-CT) Reconstruction Based on the Similarity Measure of Spatial Adjacent Images 总被引:1,自引:0,他引:1
ZHANG Shu-xu ;ZHOU Ling-hong ;CHEN Guang-jie ;LIN Sheng-qu ;YE Yu-sheng ;ZHANG Hai-nan 《中国生物医学工程学报(英文版)》2008,17(3):106-113
Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform made in house was used to create one-dimensional periodical motion that was along the longitudinal axis of the CT couch. The amplitude of sinusoidal motion was set to an amplitude of ±1 cm. The period of the motion was adjustable and set to 3.5 s. Phantom objects of two eggs were placed in a Styrofoam block, which in turn were placed on the motion platform. These objects were used to simulate volumes of interest Undergoing ideal periodic motion. CT data of static phantom were acquired using a multi-slice general electric (GE) LightSpeed 16-slice CT scanner in an axial mode. And the CT data of periodical motion phantom were acquired in an axial and cine-mode scan. A software program was developed by using VC + + and VTK software tools to resort the CT data and reconstruct the 4D-CT. Then all of the CT data with same phase were sorted by the program into the same series based on the similarity principle of spatial adjacent images and mutual information measure among them, and 3D reconstruction of different phase CT data were completed by using the software. Results:All of the CT data were sorted accurately into different series based on the similarity principle of spatial adjacent images and mutual information measures among them. Compared with the unsorted CT data, the motion artifacts in the 3 D reconstruction of sorted CT data were re- duced significantly, and all of the sorted CT series result in a 4D-CT that reflected the characteristic of the periodical motion phantom. Conclusion:Time-resolved 4D-CT reconstruction can be implemented with any general multi-slice CT scanners based on the similarity principle of spatial adjacent images and mutual information measure. The process of the 4D-CT data acquisition and reconstruction were not restricted to the hardware or software of the C 相似文献
80.
HLA-DR、DQ等位基因与精神分裂症相关性的研究 总被引:2,自引:0,他引:2
目的 证明HLA-DR、DQ等位基因与精神分裂症的发病密切相关。方法 HLA-DR、DQ等位基因检测:PCR-SSP分型。结果 发现在大连地区随机选择的精神分裂症患者的HLA-DQ8基因的频率(9.0%)明显高于正常对照(2.5%)。精神分裂症患者的HLA-DR、DQ等位基因的某些位点与免疫指标的改变有相关性。结论 ①HLA-DQ8基因与精神分裂症有关联,可以认为HLA-DQ8基因可能是精神分裂症的易感基因。②HLA-DR、DQ等位基因的某些组合可能是精神分裂症发病的危险组合模式,对预测精神分裂症的基因易感性具有潜在的应用价值。③精神分裂症的免疫指标的改变与HLA-DR、DQ等位基因的某些位点有相关性,说明精神分裂症与它的免疫指标的变化可能有内在的联系。 相似文献