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AIM:To investigate the expression of Th1-typed cytokine IFN-γ and Th2-typed cytokine IL-4 on T lymphocytes that infiltrate in nasal polyps for searching the pathogenesis of nasal polyps. METHODS:Nasal polyps tissue samples and peripheral blood were obtained from 21 patients. Normal human inferior turbinate mucosa and peripheral blood were obtained as well. Flow cytometry was adopted to detect the expression of IFN-γ and IL-4 of T lymphocytes. RESULTS: Th cytokines were rarely detected in inferior turbinate from normal human. Nasal polyps tissue consisted of abundant T lymphocytes. The expression of IL-4 and IFN-γ increased in peripheral blood from patients compared with normal human (P<0.05). The expression of IL-4 increased but the expression of IFN-γ decreased in nasal polyps compared with that of peripheral blood from the same patient (P<0.05). CONCLUSION:There were generous of T lymphocytes infiltrating in nasal polyps. There was abnormal immune status in the local nasal mucosa from the patients, and the predomination of Th cytokine secretion changed compared with peripheral blood from the same patients, which resulted in the change of microenvironment of nasal mucosa and possibly close related to the formation of nasal polyps. 相似文献
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Two disorders of almond, know as 'stem pitting’and‘graft union necrosis (black line)', were described years ago from Puglia (southern Italy). The etiology of these diseases was uncertain, the causal agent unknown and reliable diagnostic methods were not available. Investigations were therefore carried out to identify Prunus species and/or cultivars as possible indicators for a quick and reliable diagnosis. In 1990, two different almond sources (cv. Filippo Ceo) affected by black line and stem pitting were budded onto seedlings of P. persica, P. cerasifera, P. amygdalus cv. Don Carlo, GF305, self-rooted cuttings of GF677 (P. persica×P. amygdalus) and onto Don Carlo and GF305 seedlings that had been already grafted with almond cvs Genco, Tuono and Filippo Ceo. At least two inoculated plants were inspected each year for the presence of symptoms on the woody cylinder after removal of the cortex. Stem pitting developed on P. persica and P. cerasifera seedlings during the first year after graft inoculation. On the grafted plants that had been inoculated, pitting and grooving of the wood were much more pronounced in cvs Filippo Ceo and Genco, with a higher incidence when GF305 was used as rootstock. Clear symptoms were observed (from the first year in cvs Tuono and Genco), regardless of the rootstock, all along the junction line and often not associated with pitting of the rootstock and scion. 相似文献
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JIANG Xun ZENG Yao-ying HE Xian-hui XU Li-hui DI Jing-fang FENG Zheng ZHAO Jing-xian WANG Qing WANG Tong SHI Jian-bo 《园艺学报》2004,20(6):924-928
AIM: To investigate the effect of enhanced green fluorescence protein (EGFP) gene transfection on the cell cycle distribution of primary cultured human chondrocytes in order to establish a tracking method of cultured human nasoseptal chondrocytes. METHODS: pEGFP-N1 plasmid was amplified in E.coli, and purified by high purity kit. Primary cultured human chondrocytes,which were initially obtained from the nasoseptal cartilage, were cultured in vitro and transferred with pEGFP-N1 by means of electroporation with Amaxa nucleofector device. Transfering process and transient expression were evaluated by laser scanning confocal microscope (LSCM), the transfer efficiency and the cell cycle distribution were evaluated by flow cytometry. RESULTS: There was significant expression of EGFP at 24 h after transferring. The transfection efficiency of pEGFP-N1 into primary cultured human chondrocytes reached 35.37% at 48 h. It didn't affect the process of cell adherance and had no effect on the cell cycle distribution. CONCLUSION: Primary cultured human chondrocytes, which were transfected with pEGFP, are alive in vitro, and the transferring process doesn't affect the cell cycle distribution. These results suggest that pEGFP-N1 is an ideal transient expression vector for primary cultured human chondrocytes and it might be a well tracer in construction tissue engineered cartilage. 相似文献
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DU Yi-mei TANG Ming LIU Chang-jin HONG Zhi-gang KE Qin-mei DI Jiu-fang LUO Hong-yan HU Mou-xian HU Xin-wu XI Jiao-ya TANG Bi Jurgen Hescheler 《园艺学报》2004,20(9):1537-1541
AIM: To determine the role of Kv1.2, Kv1.5, Kv2.1 in the hypoxia pulmonary vasoconstriction (HPV). METHODS: Male Wistar rats were divided into two groups: normoxic group and hypoxic group. The single smooth muscle cell was obtained from pulmonary artery of Wistar rats with acute enzymatic digestion method. The conventional whole-cell patch clamp technique was used to record the resting membrane potential (Em) and the potassium currents of voltage-gated potassium channel (IKv) in rat pulmonary arterial smooth muscle cells (PASMC). Intracellular application of Kv1.2/Kv1.5/Kv2.1 antibodies (1∶125) was conducted through the whole-cell patch clamp system. RESULTS: ① Em of PASMC was depolarized after 24 h hypoxia compared with that of control cells . IKv of PASMC was decreased after 24 h hypoxia, . ② The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies depolarized Em and inhibited IKv in PASMC from normoxic rat, whereas the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on them. ③ The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies and the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on IKv and Em from rats hypoxic for 24 h. CONCLUSION: Kv1.2, Kv1.5, Kv2.1 might be oxygen sensitive potassium channels which mediated HPV. 相似文献
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旨在对辽宁绒山羊和内蒙古绒山羊的基因组选择信号进行筛选。本研究利用Illumina 50K的山羊芯片,对内蒙古绒山羊、辽宁绒山羊和黄淮山羊进行基因型检测,质控后获得50 010个共同SNPs位点。通过群体分化系数Fst和XP-EHH,以黄淮山羊为参考群体分别对内蒙古绒山羊和辽宁绒山羊进行选择信号检测,Fst和XP-EHH值的top 5%作为阈值。结果,利用Fst在绒山羊基因组中筛选到501个候选基因,利用XP-EHH在绒山羊基因组中筛选到145个候选基因。其中有12个SNPs在绒山羊基因组中受到较强选择。通过基因注释筛选到21个候选基因,包括EXOC4、ASIC2、PCDH9、RHBDD1、IRS1和PDE10A等。这些基因主要富集在PI3K-Akt信号通路、蛋白质消化吸收和松弛素信号通路等。研究结果发现,绒山羊在驯化过程中其基因组很多与毛囊相关的基因受到了强烈的选择。这些发现也有助于更好地了解绒山羊的选择进展,为中国绒山羊品种的种质资源保护和利用提供重要参考。 相似文献