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排序方式: 共有110条查询结果,搜索用时 17 毫秒
1.
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
2.
Kamrai Woranoot Rattikarn Buaruang Kodchakorn Aranyakanon Kumrop Ratanasut Anupan Kongbangkerd Panatda Jannoey Pranee Nangngam Chonnanit Choopayak 《水稻科学》2019,26(5):290-299
Activators of sesquiterpene synthase (STS) gene expression and sesquiterpene production in Piper betle L. were examined using quantitative real time PCR and gas chromatography mass spectrometry methods, and the allelopathic activity of untreated and Fusarium solani-treated betel extracts was tested on seed germination and on the shoot and root growth of Thai rice variety PSL2 (Oryza sativa cv. Phitsanulok 2) and three dominant paddy weeds (Eclipta prostrata, Echinochloa crus-galli and Chloris barbata). The results demonstrated that F. solani dramatically upregulated STS expression and productions of β-cubebene, β-caryophyllene and germacrene D sesquiterpene when compared with the untreated control, and that betel extracts had a greater inhibitory effect on weeds than on rice. The effects were more clearly detected on seed germination and root growth than on shoot growth, and they were found to be dose-dependent. It is also noted that F. solani-treated extract had stronger effects than the untreated extract. The species most sensitive to the allelopathic effects was C. barbata, germination of which was completely inhibited even at a dose of 0.1 mg/mL untreated extract. With regards to rice, although betel extract at 1.0 mg/mL showed no inhibition on germination, it affected the elongation of rice roots, in addition to those of the tested weeds. The obtained data suggested that F. solani has potential as an activator of sesquiterpene allelochemical production via STS expression, the latter leading to the treated betel extract having a stronger phytotoxic effect. These results were beneficial in the promotion of natural herbicide production using biotechnology. 相似文献
3.
为了克服有线测控系统接线复杂和抗干扰性差的缺点,开发了一种基于Zigbee无线传感器网络的鸡舍测控系统.该系统由上位PC机、基于CC2430的中心控制节点、传感器节点、传感器模块和执行机构组成.系统采用模糊控制算法实现温度的精确控制;用C语言在IAR Embedded Workbench for MCS-51 Evaluation 环境下开发无线传感器节点程序;基于Visual C++6.0平台开发了上位机控制系统软件.运行实验表明,控制系统工作稳定可靠,满足了鸡舍控制的功能要求. 相似文献
4.
基于ZigBee的分布式数据采集系统设计 总被引:1,自引:0,他引:1
张利峰 《金陵科技学院学报》2011,27(1):5-8
针对环境监测的特点、融合嵌入式技术和ZigBee,采用单片机+CC2430设计了一种结构简单、性价比高、扩充灵活的分布式数据采集系统。提供了系统总体设计方案,并详细说明其中的硬件与软件设计要点,阐明系统的应用特点和应用前景。 相似文献
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针对西部农业设施需求,以开发一套性能可靠,低成本,构建灵活,易升级的温室测控系统为目标,在借鉴国内外在温室测控系统研究中的成功经验基础上,将无线通信技术应用于温室群的测控系统中,提出了一种新型温室测控系统方案,在此基础完成了其硬件和软件开发。详细阐述了该方案组成及相关传感器电路和控制电路的设计,该设计系统具有性能可靠、成本低、构建灵活、易升级等特点,有良好的推广前景。 相似文献
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8.
基于ZigBee的淡水养殖溶氧浓度自动监控系统 总被引:2,自引:0,他引:2
无线传感器网络是近年来兴起的一门新兴技术,主要应用在自动控制和远程测控领域.本文介绍了ZigBee技术的特点,给出了基于ZigBee技术养殖自动加氧系统的工作原理和控制电路的软硬件设计.测试结果表明:系统具有结构简单、性能可靠等特点. 相似文献
9.
本研究于1977年在雅安市本校农场,就五个光、温反应特性不同品种:DissiD52/37、矮脚南特、矮子占、71—56、IR_8作亲本,采用非限定半双列杂交获得10个杂种F_1,对其高温短日生育期、短日促进率(短日敏感性),高温促进率(感温性)进行了测定。结果(1)短的高温短日生育期在杂种F_1表现呈完全显性或超亲显性;(2)在适温条件下,短日促进率(短日敏感性)高的,在杂种F_1表现为完全显性或超亲显性。并观察到在适温以下低温条件,明显抑制了短日敏感性的表现;(3)在自然日照下,高温促进率低的特性,杂种F_1表现为完全显性,而在短日处理下结果恰相反,即高温促进率高的为完全显性或超亲显性。另外,讨论了水稻品种光、温特性之间的相互制约关系。 相似文献
10.