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921.
922.
923.
The increased microvascular permeability appears mainly in venule during inflammation, shock, and burns. Endothelial cells play an important role in venule permeability enhancement. There are two kinds of pathway for macromolecule extravasation. One is paracellular pathway and another is transcellular pathway, which are related to the formation of endothelial gap or transcellular openings seperately. The alteration of intercellular related protein, such as occludin, claudin, zona occludens (ZO), junctional adhesion molecule (JAM), VE cadherin, catenin, integrin, etc, and the alteration of endothelial cytoskeleton, such as rearrangement of actin filament, formation of stress fiber and focal adhesion, etc, involve in the pathogenesis of increased microvascular permeability. 相似文献
924.
AIM:To examine the expression of T-cell immunoglobulin mucin 1 (TIM-1) on tryptase-positive mast cells (MCs) in different severities of human chronic periodontitis. METHODS:Human gingival specimens (n=92) were involved in this study, including healthy control (n=27), mild chronic periodontitis (n=34) and severe chronic periodontitis (n=31). The gingival specimens were fixed in 4% formaldehyde. Paraffin embedding and serial sectioning with hematoxylin and eosin staining were performed for histopathological examination, and double-immunofluorescence staining was conducted for identification of tryptase-TIM-1 double-positive MCs in the gingival tissues. RESULTS:Compared with the healthy controls, the densities (cells/mm2) of tryptase-TIM-1 double-positive MCs were significantly increased in both mild chronic periodontitis group (P<0.05) and severe chronic periodontitis group (P<0.01). However, compared with mild chronic periodontitis group, both the score of gingival tissue inflammation and the density of tryptase-TIM-1 double-positive MCs in the gingival tissues were significantly increased in severe periodontitis group (P<0.05). CONCLUSION:Significantly increased number of tryptase-TIM-1 double-positive MCs has the similar tendency as the severity of periodontitis inflammation in human chronic periodontitis, suggesting that tryptase-TIM-1 double-positive MCs may play an important role in human chronic periodotitis. 相似文献
925.
AIM:To explore the role of survivin-2B in the process of tumor cell apoptosis. METHODS:The survivin-2B gene was cloned into pcDNA3.1 vector and the recombinant plasmid pcDNA3.1-survivin-2B was obtained. Human breast cancer MCF7 cells were transfected with pcDNA3.1 and pcDNA3.1-survivin-2B using Lipofectamine 2000. The cell cycle was determined by propidium iodide staining, and the apoptosis was detected by annexin V/7-AAD staining 48 h after transfection. Meanwhile, tatal RNA was extrated and multiplex polymerase chain reaction based on GenomeLab GeXP Genetic Analysis System was performed to detect the expression of 21 tumor-related genes. RESULTS:Flow cytometry analysis indicated that over-expression of survivin-2B promoted the apoptosis and cell cycle arrest of MCF7 cells. Compared with control group, totally 10 differential expressed genes were related to the over-expressed survivin-2B, among which 2 were up-regulated and 8 were down-regulated. The expression of aldehyde dehydrogenase 4 family member A1 (ALDH4A1) was 48% down-regulated, and the expression of protein regulator of cytokinesis 1 (PRC1) was 1.08 folds up-regulated. CONCLUSION:Survivin-2B induces the expression changes of some tumor-related genes, which results in the apoptosis and G2/M arrest of MCF7 cells. 相似文献
926.
927.
重回缩修剪对龙眼叶片内源激素含量的影响 总被引:1,自引:0,他引:1
对交叉封行的大乌圆龙眼树(8年生)进行重回缩修剪,重剪后用167mg/LPP333溶液调节树体生长,冬季喷施450mg/L乙烯利控梢促花,研究其对龙眼叶片内源激素的影响。结果表明:实施重回缩修剪后,大乌圆龙眼叶片的乙烯、IAA含量下降,GA3、ZT含量增加,而对ABA含量影响不大;重回缩修剪后施PP333,叶片乙烯、IAA和ABA含量增加,GA3、ZT含量下降。在龙眼花芽生理分化期,重回缩修剪树叶片内源激素处于较高GA3、较低ZT水平,据此认为这是导致龙眼重回缩修剪树难以花芽分化的主要原因之一。 相似文献
928.
929.
柳糖一号(原名桂柳01-07)是柳州市农业科学研究所以F172为母本,CP67/412为父本采用有性杂交经过10年的常规选育而成,具有早熟、高产高糖等优良特性。2007—2009年在广西甘蔗品种区域试验及生产试验中,柳糖一号的11月至1月份的平均甘蔗糖分分别为15.53%、15.09%,比对照种ROC16的糖分分别高0.60%、0.68%;柳糖一号的产蔗量分别为88085kg/hm2、95865kg/hm2,与对照种ROC16相当;柳糖一号的含糖量分别为13720kg/hm2,14460kg/hm2,比对照种ROC16分别增产4.33%、5.82%。柳糖一号于2010年5月通过广西农作物品种审定委员会审定。 相似文献
930.
AIM: To investigate the effect of anti-Sonic hedgehog(Shh) blocking antibody on the killing effect of peripheral blood mononuclear cells(PBMCs) on cervical carcinoma HeLa cells. METHODS: The expression levels of Shh and Shh signaling molecules in HeLa cells were detected by immunocytochemistry and RT-PCR. PBMCs from health peoples were isolated by the method of Ficoll density gradient centrifugation, and then co-cultured with HeLa cells in vitro. The expression of CD3, CD69 and CD71 was assayed by flew cytometry. The concentrations of IFN-γ, IL-10 and IL-4 in culture supernatants were detected by ELISA. The killing effect of PBMCs on HeLa cells was observed under microscope. RESULTS: Shh and Shh signaling molecules were expressed in HeLa cells. The level of Shh expression didn't change significantly in the 6th passage of HeLa cells. CD3+ cells were increased in the co-culture system. The expression of CD69 and CD 71, and the secretion of IFN-γ were increased, while the secretion of IL-10 was decreased in the co-culture system treated with anti-Shh blocking antibody. Anti-Shh blocking antibody has no effect on the secretion of IL-4. The killing effect of PBMCs on HeLa cells was strengthened by anti-Shh blocking antibody. CONCLUSION: Anti-Shh blocking antibody promotes the activation of PBMCs and enhances the killing effect of PBMCs on cervical carcinoma HeLa cells. 相似文献