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821.
天然角蛋白自身反应性B细胞亚群及功能的分析 总被引:2,自引:0,他引:2
目的:明确天然角蛋白反应性B细胞的亚群及解剖定位,初步分析其分泌天然抗角蛋白自身抗体(anti-keratinautoantibody,AKautoAb)的能力。方法:取SPF级C57BL/6小鼠的脾细胞和腹腔细胞,荧光抗体染色后用流式细胞仪分析角蛋白反应性B细胞亚群。将脾脏和腹腔淋巴细胞体外培养后,用ELISA分析AKautoAb的滴度,用ELISPOT法分析分泌AKautoAb的B细胞数。结果:腹腔中几乎所有结合角蛋白的B细胞均为B-1a细胞,脾脏中结合角蛋白的B细胞以边缘带B细胞为主。腹腔细胞中分泌AKautoAb的细胞数显著多于脾细胞,其培养上清中AKautoAb的滴度显著高于脾细胞。结论:角蛋白反应性B细胞存在于3个成熟B细胞亚群:B-1细胞、滤泡B细胞和边缘带B细胞,其中CD5 的B-1a细胞具有活跃的分泌AKautoAb的能力。 相似文献
822.
Li N Fan XG Chen ZH Huang Y Quan J Liu ZB 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2005,113(10):647-654
Unmethylated CpG dinucleotides in bacterial DNA or synthetic oligodeoxynucleotides containing immunostimulatory CpG motifs (CpG ODN) are known as a potent Th1-like immune enhancer in vertebrates. Chronic hepatitis B is the immunocompromising condition. We therefore investigated the effects of CpG ODN on cultured cells from chronic hepatitis B patients and healthy controls. The inhibitory effects of CpG ODN on hepatitis B virus (HBV) were also studied. The secretion of IFN-alpha by CpG ODN-activated peripheral blood mononuclear cells (PBMCs) from chronic hepatitis B patients and healthy controls was significantly increased when compared with PBMCs alone or GpC ODN-stimulated PBMCs. After activation with CpG ODN, the IFN-alpha secretion by chronically HBV-infected patient PBMCs is less than that by healthy control PBMCs. Treatment of HepG2 2.2.15 cells with culture supernatants of PBMCs activated by CpG ODN can significantly suppress the secretion of HBsAg, HBeAg and HBV DNA as compared with that of PBMCs without CpG ODN activation under the same conditions. No inhibitory effect on the replication of HBV was found for CpG ODN treatment alone. Our results indicated that CpG ODN could efficiently enhance the immune response of chronic hepatitis B patients. Moreover, the CpG ODN-activated PBMCs from chronic hepatitis B patients were able to significantly inhibit HBV replication in vitro, suggesting that CpG ODN may be a potential immunoregulator against HBV infection in the future. 相似文献
823.
824.
戴维斯在线认知问卷在538名医学生中的试用 总被引:1,自引:0,他引:1
目的:建立戴维斯在线认知问卷中文版,并测试其信度和效度。方法:538名学生完成了戴维斯在线认知问卷,统计分析量表的信度和效度,并进行验证性因子分析。结果:戴维斯在线认知问卷中文版内部一致性系数为0.937,重测信度为0.905;验证性因子分析表明,各条目对4个一阶因子的标准负荷系数在0.423~0.814之间,4个一阶因子对上一级潜在因子的标准负荷系数在0.741~0.971之间;整体模式的适配度指标均符合心理测量学要求(RMSEA=0.012,GFI=0.943,NFI=0.931,CFI=0.994)。结论:戴维斯在线认知问卷中文版具有良好的信度和效度,可以作为一种较好的网络成瘾程度评价工具在我国青少年中使用。 相似文献
825.
Enhanced responses of the anterior cingulate cortex neurones to colonic distension in viscerally hypersensitive rats 总被引:5,自引:0,他引:5
The anterior cingulate cortex (ACC) is critically involved in processing the affective component of pain sensation. Visceral hypersensitivity is a characteristic of irritable bowel syndrome. Electrophysiological activity of the ACC with regard to visceral sensitization has not been characterized. Single ACC neuronal activities in response to colorectal distension (CRD) were recorded in control, sham-treated rats and viscerally hypersensitive (EA) rats (induced by chicken egg albumin injection, i.p ). The ACC neurones of controls failed to respond to 10 or 30 mmHg CRD; only 22% were activated by 50 mmHg CRD. Among the latter, 16.4% exhibited an excitatory response to CRD and were labelled 'CRD-excited' neurones. In contrast, CRD (10, 30 and 50 mmHg) markedly increased ACC neuronal responses of EA rats (10%, 28% and 47%, respectively). CRD produced greater pressure-dependent increases in ACC spike firing rates in EA rats compared with controls. Splanchnicectomy combined with pelvic nerve section abolished ACC responses to CRD in EA rats. Spontaneous activity in CRD-excited ACC neurones was significantly higher in EA rats than in controls. CRD-excited ACC neurones in control and EA rats (7 of 16 (42%) and 8 of 20 (40%), respectively) were activated by transcutaneous electrical and thermal stimuli. However, ACC neuronal activity evoked by noxious cutaneous stimuli did not change significantly in EA rats. This study identifies CRD-responsive neurones in the ACC and establishes for the first time that persistence of a heightened visceral afferent nociceptive input to the ACC induces ACC sensitization, characterized by increased spontaneous activity of CRD-excited neurones, decreased CRD pressure threshold, and increased response magnitude. Enhanced ACC nociceptive transmission in viscerally hypersensitive rats is restricted to visceral afferent input. 相似文献
826.
目的:研究金属硫蛋白(MT)对同型半胱氨酸(Hcy)诱导大鼠血管平滑肌细胞(vascularsmoothmusclecells,VSMCs)增殖的影响及其作用机制。方法:以[3H]-TdR掺入法测定VSMCs增殖程度,免疫沉淀法测定VSMCs内丝裂素活化蛋白激酶(MAPK)活性,[109Cd]-血红蛋白饱和法测定MT含量,硫代巴比妥酸法测定丙二醛(MDA)含量,NADH氧化法测定乳酸脱氢酶(LDH)漏出量。结果:Hcy(10-6-10-4mmol/L)呈浓度依赖性的刺激培养大鼠VSMCs[3H]-TdR掺入,0.1mmol/LHcy刺激[3H]-TdR掺入比对照组高4.2倍(P<0.01)。Hcy亦呈浓度依赖性地激活VSMCsMAPK活性、增加细胞MDA的生成和LDH的漏出(P均<0.01)。单独MT孵育,对VSMCs的上述指标均无明显影响(P>0.05)。但MT(10-6-10-4mol/L)呈浓度依赖性抑制100μmol/LHcy的促增殖效应(r=0.98,P<0.01)。MT显著抑制Hcy对VSMCs的MAPK活性、MDA生成和LDH漏出的激活作用(均P<0.01)。以0.5mmol/LZnCl2预孵育6h后,VSMCsMT含量比非诱导细胞高5.7倍(P<0.01),这种内源性MT高表达的细胞,显著抵抗Hcy刺激的-TdR掺入和MAPK激活;抑制Hcy的促细胞MDA生成与LDH漏出效应(均P<0.01)。结论:MT能有效抑制Hcy促大鼠VMSCs增殖作用,其机制可能与MT拮抗Hcy对MAPK的激活和其抗氧化作用有关。 相似文献
827.
828.
Toshinosuke Akutsu Ryota Imai Jun Saito Tomoyuki Suzuki 《Journal of artificial organs》2008,11(2):67-74
The Jyros (JR) valve and the newer On-X and MIRA valves, all installed antianatomically, were compared with the St. Jude Medical (SJM) valve in the mitral position to study the effects of valve design differences on the down-stream flow field and the associated valve closing sound. The dynamic particle image velocimetry method utilizing a high-speed video flow visualization technique was used to map the velocity field, and wavelet analysis of the sound was used to find the correlation between the ventricular flow field and the valve closing sound. Based on the experimental data, the following general conclusions can be made. In the velocity field directly below the mitral valve, where the distinct characteristic differences of the valve designs will be evident, twin symmetrical circulations were observed due to the divergent nature of the flow generated by the two inclined half-disks with the valve installed in the anti-anatomical orientation; the SJM, the On-X, and the MIRA valves generated a centrally downward circulation that opposed the valve leaflet closing movement, and resulted in relatively loud valve closing sounds. 相似文献
829.
目的:观察肉苁蓉提取物管花苷B对H:O:诱导的PCI2细胞损伤的影响.方法:用MTr法检测细胞存活率,以激光共聚焦显微镜荧光染色法检测细胞内活性氧的产生和线粒体膜电位的变化,DNA琼脂糖凝胶电泳和流式细胞仪检测细胞凋亡的发生,并用荧光酶标仪测定caspase-3的活性.结果:100 μmol稬-1H2O2处理细胞24 h显著降低细胞的存活率;诱导细胞发生凋亡,凋亡率达48.O%;细胞内活性氧水平及caspase-3的活性显著升高;而线粒体膜电位却明显降低,红/绿荧光强度的比值由正常的5.97降低为0.41左右.而预先给予l、10或100 mg.L-1浓度的管花苷B处理细胞12 h,可显著提高细胞存活率;并可有效抑制DNA ladder的发生;流式细胞仪检测凋亡率分别降低到30.9%、18.3%和6.2%;激光共聚焦显微镜结果显示管花苷B可明显降低细胞内活性氧的水平;并可逐渐恢复线粒体的高能量状态;easpase-3的活性不断降低,并呈现了一定的剂量依赖性.结论:管花苷B能显著地抑制H2O2诱导的PCI2细胞凋亡,其神经细胞保护作用可能与其降低细胞内活性氧水平,维持线粒体膜电位的高能状态和抑制caspase-3的活性有关. 相似文献
830.
目的 探讨中长跑有氧与无氧训练对血浆电解质及部分微量元素的影响 .方法 上海市及上海体院田径队中长跑运动员 ,根据个人运动专长 ,安排相应专项训练 ;12名进行有氧训练 ,14名进行无氧训练 ,分别在训练前及运动后即刻抽静脉血 ,检测血乳酸等电解质及微量元素铁、铜的水平 .结果 ①两组训练后 ,血乳酸、Na、Cl及无机磷(P)水平均显著升高 (p <0 .0 1) ;无氧组训练后 ,血清总钙 (Ca)及血清铁 (Fe)水平均显著升高 (p <0 .0 1) .②两组训练后 ,Cu水平显著下降 (p <0 .0 1,下降幅度均达 35 %以上 ) ;无氧组训练后 ,K水平有下降趋势 (p =0 .0 6 ) .③有氧组训练后 ,乳酸升高与K水平呈显著相关 ((r=- 0 .6 73,p <0 .0 5 ) ;无氧组训练后 ,乳酸升高与Mg水平显著相关 (r=0 .5 5 1,p<0 .0 5 ) ,与Na水平呈极显著相关 (r=0 .731,p <0 .0 1) .结论 ①有氧、无氧训练对电解质及微量元素水平的影响明显不同 .②无氧训练较有氧训练更需注意运动后电解质紊乱 ,尤需注意运动后血钙水平的升高及血钾水平的下降 . 相似文献