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We extracted marine low-temperature lysozyme (MLTL), a novel lysozyme, from a marine microorganism through fermentation. Our
previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity through antiangiogenesis. In this
study, we extracted a high weight (39 kDa) and investigated its antiangiogenic activity in vivo and in vitro. Using zebrafish embryos as an in vivo study model, we found that treatment with MLTL significantly inhibited the growth of subintestinal vessels (SIVs) in a dose-dependent
manner and that 400 μg/ml MLTL was sufficient to block the growth of SIVs. An in vitro study conducted using human umbilical vein endothelial cells (HUVECs) revealed that MLTL suppressed the proliferation, migration
and tube formation of HUVECs in a dose-dependent manner. Interestingly, assays by flow cytometry and DNA electrophoresis indicated
that MLTL was able to induce apoptosis of HUVECs. Moreover, further study demonstrated that the disruption of intracellular
Ca2+ homeostasis may play an important role in MLTL induced apoptosis of HUVECs. Taken together, the results of this study demonstrate
for the first time that MLTL inhibits angiogenesis through its pleiotropic effects on vascular endothelial cells and induces
apoptosis through regulation of cellular Ca2+ levels. The results of this study also revealed a possible mechanism underlying the antiangiogenic effect of MLTL and suggested
that MLTL may be a promising new antiangiogenic agent for use in cancer therapy. 相似文献
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1 INTRODUCTION Active oxygen free radicals can damage cell structure, even kill the cells, causing aging and cer- tain serious diseases (Bors et al., 1989). Usually, the production and scavenging of active oxygen free radicals are in balance in healthy hu… 相似文献
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扇贝多肽在体外对免疫细胞活性的影响及其抗紫外线的氧化损伤作用 总被引:9,自引:2,他引:9
采用噻唑盐(MTT)比色方法研究在紫外线辐射损伤条件下扇贝多肽对免疫细胞的保护作用,并探讨扇贝多肽对胸腺细胞和脾细胞活性的影响,结果表明,扇贝多肽具有抗紫外线氧化损伤的作用,可减轻或抑制紫外线对胸腺细胞和脾细胞的氧化损伤,并且呈剂量依赖性,扇贝多肽在0.5%-10.0%的浓度范围内,其抗氧化能力随浓度的增高而增强,在正常条件下可显著增强免疫细胞的活性,并且可拮抗雌激素对免疫细胞的抑制作用。提示扇贝多肽不仅具有抗氧化损伤作用,而且具有免疫增强使用。 相似文献
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王春波 《测绘与空间地理信息》2012,35(4):178-179
为了减少外业工作量,利用航空摄影测量进行基础地理信息采集是最有效手段之一,国内外推出了一系列数字摄影测量的软件和系统.本文结合GEOWAY DPS/IS及VirtuoZo AAT(PATB)两种软件的生产实践,探讨了基于粗纠正影像源进行1∶10000数字线划图(DLG)生产“内外业一体化”的工艺流程.本文对以后采用此种方法成图具有一定的指导作用. 相似文献
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1 INTRODUCTION Long-term exposure of the skin to ultraviolet (UV) radiation results in degenerative processes involved in photoaging and photocarcinogenesis (Differy, 1987). As UVC is absorbed entirely by the stratospheric ozone layer and does not reach the earth抯 surface, sunlight is composed of UVA (320 nm 400 nm) and UVB (290 nm 320 nm). Human skin is exposed constantly to both UVA and UVB radiation, it is, therefore, important to protect the skin against UVA and UVB-induce… 相似文献
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由于1∶500地形图精度要求很高,因此利用全数字摄影测量方法测绘时,精度很难达到要求,甚至有很多人认为用此种方法根本达不到1∶500地形图要求的精度指标。但经过我们的生产实践,1∶500地形图的精度完全可以保证。本文提出了利用全数字摄影测量方法测绘1∶500地形图时保证精度的具体措施,对以后采用此种方法成图具有一定的指导作用。 相似文献
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王春波 《测绘与空间地理信息》2015,(11)
对于已有1∶10 000数字线划图(DLG)数据的区域,利用1∶10 000 DLG作为2米格网数字高程模型(DEM)数据主要资料源,采用基于DLG数据内插DEM的作业流程软件进行生产,最终得到精细化DEM成果数据。 相似文献
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为了综合全面地反映城市群高速铁路规划线网的总体性能,评价比选出最优规划方案,针对复杂多因素约束条件下评价指标信息的非“二分法”特性,本文在GIS技术支持下,尝试提出了基于区间直觉模糊集的城市群高速铁路线网评价模型。该模型从区间直觉模糊数的几何意义出发,基于熵值最大化原理,求出指标的权重,获得不同决策者对各个方案的评价值。最后,综合不同决策者意见得出各个方案的最终评价值。以辽中南城市群高速铁路线网规划评价为例,进行了基于区间直觉模糊集的城市群高速铁路线网方案评价。分析表明提出的方法能够描述决策者判断过程中的犹豫程度,可以更细腻、更全面地描述评价指标的自然属性,从而使评价结果更符合客观实际情况。 相似文献