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101.
抗角蛋白抗体进入活细胞的共聚焦显微镜观察 总被引:1,自引:0,他引:1
目的:观察抗角蛋白抗体能否进入活细胞。方法:以鼠单克隆抗体(mAb)IgG作用于培养中的人Tca8113细胞,以黑素瘤细胞和抗HBsAg抗体作用的Tca细胞作为阴性对照。细胞固定后与FITC标记的羊抗鼠IgG结合,用荧光显微镜及共聚焦显微镜,观察细胞的荧光着色。结果:抗角蛋白mAb作用的Tca8133细胞胞浆呈亮绿色,着色较均匀,细胞核未见着色。两种对照均未见着色。结论:抗角蛋白mAb可进入活细胞,并结合于胞浆成分。 相似文献
102.
Diisocyanate asthma and gene-environment interactions with IL4RA, CD-14, and IL-13 genes. 总被引:1,自引:0,他引:1
David I Bernstein Ning Wang Paloma Campo Ranajit Chakraborty Andrew Smith André Cartier Louis-Philippe Boulet Jean-Luc Malo Berran Yucesoy Michael Luster Susan M Tarlo Gurjit K Khurana Hershey 《Annals of allergy, asthma & immunology》2006,97(6):800-806
BACKGROUND: Diisocyanate asthma (DA) affects 2% to 10% of exposed workers, yet the pathogenetic mechanisms underlying this disorder remain ill defined. OBJECTIVE: To determine if specific single nucleotide polymorphisms (SNPs) of interleukin 4 receptor alpha (IL4RA), IL-13, and CD14 promoter genes are associated with DA. METHODS: Sixty-two workers with DA confirmed by specific inhalation challenge (SIC) and 75 diisocyanate-exposed, SIC-negative workers were analyzed for SNPs associated with IL4RA, IL-13, and CD14 promoter genes. RESULTS: No associations were found with individual SNPs and DA. When stratified according to specific diisocyanate exposure, a significant association was found between IL4RA (I50V) II and DA among individuals exposed to hexamethylene diisocyanate (HDI) (odds ratio [OR], 3.29; 95% confidence interval [CI], 1.33-8.14; P = .01) only. Similarly, the IL4RA (I50V) II and IL-13 (R110Q) RR combination was significantly associated with DA in HDI-exposed workers (OR, 4.13; 95% CI, 1.35-12.68; P = .01), as was the IL4RA (I50V) II and CD14 (C159T) CT genotype combination (OR, 5.2; 95% CI, 1.82-14.88; P = .002) and the triple genotype combination IL4RA (I50V) II, IL-13 (R110Q) RR, and CD14 (C159T) CT (OR, 6.4; 95% CI, 1.57-26.12; P = .01). CONCLUSIONS: Gene-environmental interactions may contribute to the pathogenesis of DA, and gene-gene interactions may modulate this relationship. 相似文献
103.
由一株抗人C1-抑物单克隆抗体鼠杂交瘤细胞提取总RNA,合成2对与免疫蛋白可变区FR1和FR4互补的通用引物,经RT-PCR扩增出抗体的重链可变区和轻链可变区基因。 相似文献
104.
原发性中枢神经系统恶性淋巴瘤MR表现及其病理学基础 总被引:5,自引:0,他引:5
目的 研究原发性中枢神经系统恶性淋巴瘤(PCNSL)的MR表现及其病理学基础。方法 分析13例手术病理证实的原发性中枢神经系统恶性淋巴瘤的临床病理及MR表现。结果 13例中单发肿瘤4例,多发肿瘤9例,共计36个病灶。13例病变均累及幕上,其中8例病灶位于深部脑白质近脑室旁。肿瘤平均最大径为3.2cm。T1WI略低信号28个,T2WI等信号24个。28个病灶呈均匀强化。肿瘤水肿及占位效应相对较轻。2例PCNSL行MR动态增强扫描,早期强化均不明显,时间-信号强度曲线呈缓慢上升型。病理上肿瘤细胞弥漫分布,瘤细胞大小较一致,细胞质少,细胞核大,染色质颗粒粗,可见瘤细胞围绕血管呈袖套样浸润,少见明显的出血及片状坏死,未见钙化,病理均为非霍奇金淋巴瘤。结论 原发性中枢神经系统恶性淋巴瘤的病理基础决定其MR增强形态、占位程度以及肿瘤发生部位具有一定特征,运用不同的MR影像学检查方法和技术,在多数情况下可以做出术前正确诊断。 相似文献
105.
双特异性抗体对LAK细胞增殖和细胞毒作用影响的体外研究 总被引:3,自引:0,他引:3
将抗CD3与抗HBs的单克隆抗体经化学偶联得到双特异性抗体,观察该双特异性抗体对LAK细胞增殖和增强细胞毒性的作用。结果显示双特异性抗体显著提高LAK细胞与2.2.15细胞结合率;促进淋巴细胞增殖。125I-UdR释放试验检测发现双特异性抗体增强LAK细胞对2.2.15细胞的细胞毒性且与抗体浓度呈正相关。进一步对抗体的特异性研究表明,加入双特异性抗体后LAK细胞对2.2.15细胞毒性作用显著高于对照组。 相似文献
106.
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
107.
目的 探讨量化非特异性相互作用在特异性选择素-配体分子相互作用中的贡献。方法 利用光镊技术,对牛血清白蛋白(Bovine serum albumin, BSA)封闭的玻璃小球间的非特异性作用进行了系统测量,得出不同加载率下的断裂力以及不同外力作用下的寿命分布。结果 实验结果表明,非特异性作用同样表现出断裂力随加载率增加而增大的趋势。在较低加载率下,非特异性断裂力与选择素-配体特异性断裂力大小、增大趋势基本一致;随着加载率增加,二者的差别逐渐显著,前者的断裂力增加速率远低于后者。同样外力作用下,非特异性作用的寿命平均值比特异性作用要小;不同外力作用下,非特异性作用的寿命随外力增大仅略有下降,与特异性作用中逆锁键-滑移键转化现象有明显不同。结论 该研究结果将为正确评估非特异性相互作用对选择素-配体特异性相互作用实验结果的影响提供基础。 相似文献
108.
Intact perceptual and conceptual priming in temporal lobe epilepsy: neuroanatomical and methodological implications 总被引:1,自引:0,他引:1
Explicit memory appears to be supported by medical temporal lobe structures, whereas separate neocortical regions may mediate perceptual and conceptual implicit memory. Children and adults with temporal lobe epilepsy (TLE) and matched controls were administered experimental verbal memory tests. Performance on implicit tests--word identification and word generation--was contrasted with explicit recognition and recall. Encoding conditions emphasized either conceptual or perceptual aspects of study words and were crossed with presentation modality. The priming performance of participants with TLE did not differ from controls, but participants with TLE did show deficits on recognition and recall measures. Thus, intact left temporal cortex does not appear to be necessary for normal implicit memory performance, even when conceptual processing is emphasized at study or test. 相似文献
109.
图像拼接能很好地解决显微镜高倍镜成像时视野减小的问题.我们在分析显微成像系统对医学显微图像灰度分布影响的基础上,提出了一个系统对图像灰度分布的影响函数.结合系统影响函数和精确匹配下的相关性方程,得到一个以最小平方和形式误差函数为基础的方程组.利用奇异值分解得到系统对图像灰度分布的影响的估计值,然后用估计值来补偿系统的影响,得到图像的原始灰度,再进行拼接.这种方法能在不影响拼接速度的前提下消除医学显微图像中存在的拼接缝和拼接痕迹. 相似文献
110.
Y. Ma S. Ren W. M. Pandak X. Li Y. Ning C. Lu F. Zhao L. Yin 《Inflammation research》2007,56(12):495-501
Objective: To investigate the expression of steroidogenic acute regulatory protein (StAR) in macrophages and the effects of inflammatory
cytokines on StAR expression.
Methods: The macrophages isolated from ApoE knockout mice and C57BL/6J mice and RAW264.7 cells (a cell line from mouse macrophage.
ATCC Number: TIB-71TM) were cultured in DMEM containing 10% fetal bovine serum. RAW264.7 cells were treated with different inflammatory cytokines
(TNF-α, IFN-γ and TGF-β1) and 8-Br-cAMP, a cAMP analog. RT-PCR and Western blot analysis were applied to evaluate the effects
of inflammatory cytokines on StAR expression.
Results: RT-PCR and Western blot analysis demonstrated the expression of StAR in the macrophages isolated from ApoE knockout mice,
C57BL/6J mice and RAW264.7 cells. Proinflammatory cytokines TNF-α and IFN-γ significantly decreased StAR mRNA and protein
levels in RAW264.7 cells. The inhibition was dose- and time-dependent. In contrast, anti-inflammatory cytokine TGF-β1 increased
StAR mRNA and protein levels. At 1:15 molecular ratio, TGF-β1 blocked the down-regulation of StAR expression mediated by TNF-α.
cAMP also induced StAR expression in RAW264.7 cells. When the cells were co-treated with 8-Br-cAMP and TNF-α, 8-Br-cAMP failed
to induce StAR expression.
Conclusion: Our results provide interesting evidence that inflammatory cytokines regulate StAR expression in macrophages.
Received 12 August 2006; returned for revision 28 September 2006; returned for final revision 28 May 2007; accepted by M.
Katori 22 June 2007 相似文献