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991.
JI Dan HE Xiao-gang WANF Gang LUO Tao ZHANG Lu XU Xiao-dan XU Xiao-jun LI Fei-fei 《园艺学报》2020,36(6):969-976
AIM To investigate the role of monocyte chemoattractant protein-1 (MCP-1) and its receptor CC chemokine receptor 2 (CCR2) in ethanol-promoted breast cancer angiogenesis and the underlying mechanism. METH?ODS: A mouse model of transplanted breast tumor with moderate alcohol consumption was established. The correlations between the expression of MCP-1/CCR2 and the expression of angiogenesis markers [platelet endothelial cell adhesion molecule-1 (PECAM-1) and vascular endothelial growth factor (VEGF)] in tumor tissues were examined by immunohistochemistry. In vitro , a 3D tumor-endothelial co-culture system was established to observe tumor angiogenesis and the role of MCP-1/CCR2 signaling pathway in alcohol-mediated angiogenesis. The cell migration ability was detected to clarify whether MCP-1/CCR2 enhanced cell mobility to form new vessels. RESULTS MCP-1 and CCR2 were both highly expressed in the breast tumor tissues of tumor-bearing mice consuming alcohol, and their expression levels were consistent with the angiogenic markers PECAM-1 and VEGF (P <0.05). The interaction between mouse breast cancer E0771 cells and endothelial cells was observed to promote angiogenesis in the 3D tumor-endothelial co-culture system with or without alcohol stimulation. MCP-1 promoted this kind of tumor angiogenesis, while CCR2 antagonist effectively inhibited the tumor angiogenesis and especially blocked alcohol-induced angiogenesis. Activation of MCP-1/CCR2 signaling pathway enhanced the migration ability of endothelial cells. CONCLUSION The MCP-1/CCR2 signaling pathway plays an important role in promoting the angiogenesis of breast cancer stimulated by alcohol. The mechanism might be that MCP-1 improves the migration of endothelial cells and then promotes angiogenesis. 相似文献
992.
993.
本研究以黄伞菌丝cDNA为模板,设计简并引物,经PCR扩增出两条片段SLI和S12,经过回收、重扩增、克隆与鉴定后进行测序分析,结果发现SI.1的序列在Genebank中与三磷酸甘油醛脱氢酶(Glyceraldehyde-3-Dhosphate dehydrogease,GPD)基因的同源性达到85%,根据SLI序列设计引物,以黄伞菌丝体、原基、菇蕾、子实体菌柄、子实体菌盖的cDNA为模板进行PCR反应以验证其保守性,结果显示此片段在不同分化发育阶段表达量相同。 相似文献
994.
995.
番茄灰霉病菌拮抗菌的筛选和应用 总被引:4,自引:0,他引:4
采集番茄等蔬菜叶、根和土壤样本 1 82份 ,分离获得对番茄灰霉病菌 (Botrytiscinerea Pers.)有抑制作用的拮抗菌5 8株。其中拮抗细菌 5 4株 ,占 93 .1 % ,且多为芽孢杆菌 (Bacillus) ;拮抗真菌中木霉 (Trichoderma)和粘帚霉 (Gliocladium)各 1株。根据抑菌圈法测定 ,拮抗细菌对灰霉菌的拮抗能力有显著差异 ,其中芽孢杆菌 Y2 - 1 1 - 1 菌株拮抗性最强且稳定。试验表明 :Y2 - 1 1 - 1 悬浮液对番茄灰霉病有较好的防治效果 ,室内叶片和果实的防效分别为 69.9%和 78.2 % ;大棚内对果腐的防效 ,喷施 1次与 2次的分别为 61 .7%~ 72 .1 %和 76.6%~ 85 .3 % ,明显优于 5 0 %速克灵 (2 0 0 0倍稀释液 )。 相似文献
996.
为了探明鸭疫里默氏菌病的传染类型,对两组不同日龄的鸭人工感染鸭疫里默氏菌,于接种感染后不同时间测定其血液中细菌含量,白细胞分类计娄的动态变化,并观察其临床症状和病理变化,结果表明:两组鸭在接种感染后一个较长的时间内其外周血液中细菌含量持续大幅度上升,并且在整个试验过程中都能在血液中查到鸭疫里默氏菌,结合临床症状和病理变化,得出鸭疫里默氏菌病是一种急性或亚急生的败血型传染病,在感染12-24h后出现菌血症,后瞬即发展为败血症经过。 相似文献
997.
高效功能陶粒生物滤池处理农村生活污水研究 总被引:6,自引:1,他引:6
利用粉煤灰、锯末和铁矿石等废弃物,经造粒和高温烧结,自行开发了两种高效功能陶粒,并将其与沸石以"砖墙"式嵌套填充,构筑了高效功能陶粒生物滤池.采用该生物滤池,研究对农村生活污水(COD:200mg·L-1,NH3-N:20mg·L-1,TP:4.0mg·L-1)的深度脱氮除磷作用.结果表明,高效功能陶粒具有表面粗糙,比表面积大,机械强度高,耐酸碱性能好和无重金属溶出等优点.该生物滤池上下部分分别形成好氧区和厌氧区,从而达到深度脱氮除磷效果.在水力停留时间(HRT)为2.15~5.73 h,水力负荷为2.8~7.5 m3·m-2·d-1时,两个生物滤池对氨氮(NH3-N)、总磷(TP)和化学需氧量(COD)均具有很好的去除效果,两个功能陶粒生物滤池的去除率分别达到83.6%~98.3%、89.1%~99.7%和84.4%~95.2%,优于普通生物滤池. 相似文献
998.
999.
施用氮磷肥对苏北滩涂围垦土壤盐渍化水平的影响 总被引:1,自引:0,他引:1
以苏北滩涂围垦土壤为研究对象,采用完全随机区组设计,通过种植碱篷与施用氮磷肥等种植模式,评价不同施肥方式对围垦土壤盐渍化水平的影响。对各处理的土壤盐分八大离子、pH、EC、总碱度(TA)、钠化率(ESP)、钠吸附比(SAR)进行因子分析,提取的3个主因子解释了总方差的84.16%,并且EC、Cl-、Na+、SAR和ESP在因子1上有较高的载荷,代表滩涂土壤的盐碱特征;Ca2+与SO24-在因子2上有较高的载荷,反映土壤的结构状况;TA和CO23-在因子3上有较高的载荷,代表着滩涂土壤的碱化特征。比较盐渍化水平综合评价得分可知,裸地的盐渍化水平最高,与其他各处理相比均达到显著性差异,滩涂围垦土壤种植碱篷后,盐渍化程度均得到明显地降低。尿素与过磷酸钙对围垦土壤的盐渍化水平的影响存在交互作用,其中过磷酸钙对盐渍化的影响起主导作用。 相似文献
1000.
LI Xiao-mei YANG Yi-ning MA Yi-tong CHEN Bang-dang LIU Fen HAN Wei GAO Xiao-ming HUANG Ying 《园艺学报》2010,26(2):209-215
AIM: To explore the changes in extracellular regulated protein kinase (ERK1/2) in the hypertrophic myocardium induced by pressure overload at the different time courses and to determine the molecular mechanism in the myocardium from hypertrophy to heart failure. METHODS: C57/BL mice, aged 12 week old, were subjected to sham-operation (SH) or transversing aortic constriction (TAC) to establish left ventricular hypertrophy. Echocardiographic assessments, hemodynamic determination, organ weight measurement, morphological and histological examination were performed at 1, 4, 8, 12 and 16 weeks after surgery. Meanwhile mRNA levels of atrial natriuretic peptide (ANP), α-myosin heavy chain (α-MHC), bcl-2 and bax were measured by RT-PCR, and ERK1/2 levels were detected by Western blotting. The animals in SH group were performed the same tests then sacrificed at 16 weeks. RESULTS: (1) Compared to SH group, LVESd, LVEDd, Awsth, Awdth, Pwsth and Pwdth progressively increased after TAC. Meanwhile, ejection fraction (EF%) significantly decreased at 16th week (P<0.05). LVSP, dp/dtmax and dp/dtmin in TAC group were progressively increased after 4 weeks. From 8-12 weeks these parameters maintained stable and then sharply decreased at 16th week (all P<0.05). However, LVEDP was statistically increased at 8th week. These echocardiographic and hemodynamic changes indicated a development of LVH and eventually progressing towards to heart failure. (2) Histologically, cardiac collagen measured by percentage of Sirius red positive stained area and apoptosis index showed progressive increases from 4 to 16 weeks. (3) Compared to SH group, mRNA levels of ANP was time-dependently increased while α-MHC and Bcl-2 were time-dependently decreased. The ratio of Bcl-2 /Bax was decreased. Phosphorylation of ERK1/2 was increased at 4th week, then decreased with age of TAC (all P<0.05). CONCLUSION: Pressure-overload induced by TAC results in a development of LVH from early concentric hypertrophy to late eccentric hypertrophy, and eventually toward cardiac dysfunction or heart failure. Those changes are associated with increase in cell size and cardiac fibrosis. ERK1/2 signaling pathway may involve in the regulation of myocardial cell apoptosis in hypertrophic and failure heart. 相似文献