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Implication of Expression of Osteopontin and Its Receptor Integrin αvβ3 in the Placenta in the Development of Preeclampsia 被引量:9
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作者 夏俊霞 乔福元 +1 位作者 苏放明 刘海意 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第6期755-760,共6页
To investigate the expression of osteopontin (OPN) and its receptor integrin αvβ3 in the placental tissue from pregnant women complicated with preeclampsia, the expression of OPN and αvβ3 in the placenta of the ... To investigate the expression of osteopontin (OPN) and its receptor integrin αvβ3 in the placental tissue from pregnant women complicated with preeclampsia, the expression of OPN and αvβ3 in the placenta of the pregnant women with preeclampsia and healthy pregnant women was detected by immunohistochemistry, Western blotting and RT-PCR. Our results showed that OPN and αvβ3 protein were expressed in the placenta from normal pregnant woman and those with preeclampsia. OPN was located in the placental syncytiotrophoblasts and the cytoplasm of capillary endothelial cells and integrin αvβ3 was mainly expressed on the surface of trophoblast cells. Expression of OPN and integrin αvβ3 in the placental tissue from preeclampsia subjects was significantly lower than that from the control group (P〈0.05). Compared with the control group, expression of OPN in the placental tissue from preeclampsia group was significantly lower (P〈0.05) but there was no significant difference in the expression of αv and β3 between the preeclampsia group and the controls. It is concluded that OPN and its receptor integrin αvβ3 may be involved in the pathogenesis of preeclampsia. 展开更多
关键词 OSTEOPONTIN integrin α3 PLACENTA PREECLAMPSIA
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Effects of Integrins and Integrin αvβ3 Inhibitor on Angiogenesis in Cerebral Ischemic Stroke 被引量:3
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作者 毕佳佳 易黎 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第3期299-305,共7页
Summary: Integrins such as αvβ3, α5β31 play a key role in angiogenesis regulation, invasion and metastasis, inflammation, wound healing, etc. The up-regulation of integrin αvβ3 after cerebral ischemic stroke ca... Summary: Integrins such as αvβ3, α5β31 play a key role in angiogenesis regulation, invasion and metastasis, inflammation, wound healing, etc. The up-regulation of integrin αvβ3 after cerebral ischemic stroke can promote angiogenesis, which in turn improves functional recovery. In addition, the integrin αvβ3 inhibitor can block the blood-brain barrier (BBB) leakage induced by vascular endothelial growth factor (VEGF) and also can reduce inflammatory reaction, decrease the deposition of fibrinogen. Other studies showed that integrin αvβ3 is not essential in revascularization. Therefore, the effect of integrin αvβ3 in the whole process of brain function recovery merits further study. 展开更多
关键词 integrin α3 cerebral ischemic stroke vascular endothelial growth factor cyclo[Arg-Gly-Asp-D-Phe-val]
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Effect of lentivirus-mediated integrin αVβ3-sh RNA on tumor growth of mice with lung cancer xenografts 被引量:1
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作者 Tao Liang Yong-Fu Ma +2 位作者 Jian Chu Dao-Xi Wang Yang Liu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第2期160-163,共4页
Objective: To study the effect of lentivirus-mediated integrin αVβ3-sh RNA on tumor growth of mice with lung cancer xenograft. Methods: Lung cancer tissue, paracancer tissue and normal tissue were collected and inte... Objective: To study the effect of lentivirus-mediated integrin αVβ3-sh RNA on tumor growth of mice with lung cancer xenograft. Methods: Lung cancer tissue, paracancer tissue and normal tissue were collected and integrin αVβ3 expression was detected; BALB/c nude mice were selected, divided into integrin αVβ3 knockdown group(KD group) and negative control group(NC group), and inoculated with cells stably infected by integrin αVβ3-sh RNA lentivirus and cells stably infected by negative control-sh RNA lentivirus respectively, the growth of tumor tissue was continuously observed, and the number of apoptosis cells as well as the expression of angiogenesis, apoptosis and invasion genes in tumor tissue were detected. Results: m RNA content and protein content of integrin αVβ3 in lung cancer tissue were significantly higher than those in paracancer tissue and normal tissue; increasing trend of tumor tissue volume of KD group was weaker than that of NC group, and tumor volume at various points in time of KD group was lower than that of NC group; m RNA contents and protein contents of VEGF, FGF, EGF, Bcl-2, MMP-9, MMP-12 and MMP-13 in tumor tissue of KD group were lower than those of NC group, and apoptosis index as well as m RNA content and protein content of Bax were higher than those of NC group. Conclusions: The expression of integrin αVβ3 increases in lung cancer tissue, and lentivirus-mediated integrin αVβ3-sh RNA can inhibit tumor growth of mice with lung cancer xenografts. 展开更多
关键词 Lung cancer integrin α v β 3 XENOGRAFTS Angiogenesis Apoptosis INvASION
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Effects of controlled superovulation on the expression of HOXA10,integrin αvβ3 and LIF in mice during peri-implantation
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作者 Lei Zhang Jie Liu +5 位作者 Ying Zhang Fang Wang Chang-Lei Li Ai-Ni Fu Jun You Shu-Xiu Zhu 《Journal of Hainan Medical University》 2021年第8期7-11,共5页
Objective:To observe the expression of endometrial homologous box gene A10(HOXA10),Integrinαvβ3 and leukemia suppressor factor(LIF)in peri-implantation mice,and to investigate the effect of controlled superovulation... Objective:To observe the expression of endometrial homologous box gene A10(HOXA10),Integrinαvβ3 and leukemia suppressor factor(LIF)in peri-implantation mice,and to investigate the effect of controlled superovulation(COH)on endometrial receptivity in mice.Methods:After COH model preparation and blastocyst transplantation,kunming pure-bred mature mice were randomly divided into natural blastocyst+natural pseudocyst group,COH blastocyst+natural pseudocyst group,natural blastocyst+COH pseudocyst group,and COH blastocyst+COH pseudocyst group.The pregnancy rate and average number of beds in each group were observed on day 6 of conception.Western blot and RT-PCR were used to detect the expression of HOXA10,Integrinααvβ3,LIF protein and mRNA in the endometria of mice on day 5 of conception.Results:The pregnancy rate and average number of beds in the COH group were lower than those in the natural receptor group.The expression of HOXA10,Integrinααvβ3 and LIF in endometrium was significantly lower than that of the natural receptor mice(P<0.01).Conclusion:Superovulation drugs down-regulate the expression of HOXA10,Integrinαvβ3 and LIF in endometrium during the implantation window,reduce endometrial receptivity,and lead to low clinical pregnancy rate. 展开更多
关键词 Controlled superovulation Endometrial receptivity Homologous box gene A10 integrinα3 Leukemia suppressor
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Integrin α_vβ_3靶向超声微泡的制备及体外寻靶实验 被引量:3
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作者 刘莹莹 徐金锋 +5 位作者 严飞 曾欣欣 魏章洪 刘慧玉 郑静 周玉丽 《中国医学影像技术》 CSCD 北大核心 2016年第2期175-178,共4页
目的制备Integrinαvβ3靶向超声微泡,对其一般理化性质及体外寻靶能力进行检测。方法采用巯基-马来酰亚胺连接法制备携FITC标记iRGD肽的Integrinαvβ3靶向微泡(MBIntegrinαvβ3),并制备空白微泡(MBcontrol)。检测两组微泡的一般理化... 目的制备Integrinαvβ3靶向超声微泡,对其一般理化性质及体外寻靶能力进行检测。方法采用巯基-马来酰亚胺连接法制备携FITC标记iRGD肽的Integrinαvβ3靶向微泡(MBIntegrinαvβ3),并制备空白微泡(MBcontrol)。检测两组微泡的一般理化性质,在荧光显微镜下观察两组微泡荧光显像,流式细胞仪检测两组微泡FITC荧光含量。于光学显微镜及荧光显微镜下观察两组微泡与小鼠脑微血管内皮细胞(bEnd.3)的黏附情况。结果 1MBIntegrinαvβ3粒径为(0.84±0.26)μm,与MBcontrol粒径(0.79±0.19)μm差异无统计学意义(P>0.05);2荧光显微镜下观察,MBcontrol组微泡无荧光显示,MBIntegrinαvβ3组微泡表面显示绿色荧光;3流式细胞仪测得MBIntegrinαvβ3组微泡FITC荧光含量为98.4%,MBcontrol组微泡FITC荧光含量为2.5%;4体外寻靶实验显示,MBIntegrinαvβ3组微泡能聚集结合于bEnd.3细胞表面。结论成功制备了携iRGD肽的Integrinαvβ3靶向微泡,其具有良好的体外寻靶能力。 展开更多
关键词 整合素Α3 造影剂 超声检查 靶向 微泡
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Ischemic preconditioning partially suppresses and postpones integrin α_Vβ_3 mRNA expression following transient global cerebral ischemia in C57BL/6 mice
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作者 Mei Liu Xiaomeng Ma +5 位作者 Xiaohong Chen Ying Jiang Aimin Wu Fuhua Peng Yingying Liu Rongbiao Pi 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第23期1782-1786,共5页
Previous studies of integrin αvβ3 have focused on ischemic brain damage, although the role of integrin αvβ3 in ischemic preconditioning (IP) has rarely been reported. The present study analyzed the effects of IP... Previous studies of integrin αvβ3 have focused on ischemic brain damage, although the role of integrin αvβ3 in ischemic preconditioning (IP) has rarely been reported. The present study analyzed the effects of IP on integrin αvβ3 mRNA expression following cerebral ischemia through the use of hematoxylin-eosin staining and real-time quantitative polymerase chain reaction techniques. Integrin avid3 mRNA expression in the ischemia group peaked at 24 hours after ischemia-reperfusion. In the IP + ischemia group, integrin αvβ3 mRNA expression increased after 24 hours, but remained significantly less than the ischemia group, and expression continued to increase until 7 days after ischemiaJreperfusion. These results demonstrate that IP effectively attenuated upregulation of integrin αvβ3 mRNA expression at 24 hours after ischemia. 展开更多
关键词 integrin α3 ischemic preconditioning ischemic tolerance global cerebral ischemia blood-brain barrier: mice
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基于改进DeepLabv3+的轻量化作物杂草识别方法
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作者 曲福恒 李金状 +2 位作者 杨勇 康镇南 严兴旺 《石河子大学学报(自然科学版)》 CAS 北大核心 2024年第1期117-125,共9页
为在存储资源与计算能力有限的设备上实现田间作物和杂草的识别,本文提出一种基于改进DeepLabv3+的轻量化语义分割网络。首先,以MobileNet v2作为DeepLabv3+的特征提取骨干网络,提出双分支残差模块替换倒残差模块,并删除后两层卷积以降... 为在存储资源与计算能力有限的设备上实现田间作物和杂草的识别,本文提出一种基于改进DeepLabv3+的轻量化语义分割网络。首先,以MobileNet v2作为DeepLabv3+的特征提取骨干网络,提出双分支残差模块替换倒残差模块,并删除后两层卷积以降低模型参数量。其次,在空洞空间金字塔池化(Atrous Spatial Pyramid Pooling,ASPP)模块中引入分组逐点卷积,使用深度扩张卷积替换标准卷积,并将卷积后的特征图进行多尺度特征融合增强对作物和杂草深层特征的提取能力。最后,将原有的非线性激活函数替换为Leaky ReLU激活函数来提升分割精度。实验结果表明:改进后网络的mIOU达到86.75%,参数量仅为0.69M,FPS达到了98,与原始DeepLabv3+以及3个典型轻量化语义分割网络的相比,参数量最小,在对比的轻量化网络中具有最高的分割精度。 展开更多
关键词 作物和杂草识别 轻量化 语义分割 DeepLabv3+ MobileNet v2 多尺度特征融合
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改进DeepLab v3+模型下的梯田遥感提取研究
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作者 张俊 陈雨艳 +2 位作者 秦震宇 张梦瑶 张军 《智慧农业(中英文)》 CSCD 2024年第3期46-57,共12页
[目的与意义]梯田作为农业生产的关键要素之一,其面积估算对于农业政策制定、土地规划和资源管理至关重要。为解决复杂的地形条件、种植环境导致传统遥感数据和监测方法难以开展梯田自动化提取问题,探索一种利用深度学习技术在高分辨率... [目的与意义]梯田作为农业生产的关键要素之一,其面积估算对于农业政策制定、土地规划和资源管理至关重要。为解决复杂的地形条件、种植环境导致传统遥感数据和监测方法难以开展梯田自动化提取问题,探索一种利用深度学习技术在高分辨率遥感影像中精准提取梯田面积的方法。[方法]以休耕期梯田高分六号影像构建语义分割数据集,同时提出一种改进的DeepLab v3+模型。该模型使用轻量级网络MobileNet v2作为骨干网络,为了同时兼顾局部细节和全局语境,使用多尺度特征融合(Multi-scale Feature Fusion module,MSFF)模块代替空洞空间金字塔池化(Atrous Spatial Pyramid Pooling,ASPP)模块,利用扩张率依次增大的空洞卷积级联模式改善信息丢失的问题。此外,对浅层特征和深层特征使用坐标注意力机制以加强网络对于目标的学习。[结果与讨论]利用红、绿和近红外波段组合方式在梯田提取的精度和效果上表现最佳。相比于原始DeepLab v3+网络,精确率、召回率、F_(1)评分和交并比指标分别提升4.62%、2.61%、3.81%和2.81%。此外,与UNet和原始DeepLab v3+相比,改进的DeepLab v3+在参数量上和浮点运算数有着更为优越的性能,其参数量仅为UNet的28.6%和原始DeepLab v3+的19.5%,同时浮点运算数仅为UNet和DeepLab v3+的1/5。这不仅提高了计算效率,也使得改进后的模型更适用于资源有限或计算能力较低的环境中。[结论]深度学习在高分辨率遥感影像梯田识别中具有较高的精度,有利于为梯田精细化监测和管理提供参考依据。 展开更多
关键词 梯田提取 遥感 卷积神经网络 高分六号卫星 DeepLab v3+
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改进Deeplabv3+的双注意力融合作物分类方法
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作者 郭金 宋廷强 +4 位作者 孙媛媛 巩传江 刘亚林 马兴录 范海生 《计算机工程与应用》 CSCD 北大核心 2024年第8期110-120,共11页
近年来,卷积神经网络(convolutional neural networks,CNN)在农作物分类研究中不断取得新进展,但在建模长期依赖关系方面表现出一定的局限性,对农作物全局特征的捕获存在不足。针对以上问题,将Transformer引入Deeplab v3+模型,提出了一... 近年来,卷积神经网络(convolutional neural networks,CNN)在农作物分类研究中不断取得新进展,但在建模长期依赖关系方面表现出一定的局限性,对农作物全局特征的捕获存在不足。针对以上问题,将Transformer引入Deeplab v3+模型,提出了一种用于无人机影像农作物分类的并行分支结构--DeepTrans(Deeplab v3+with Trans-former)模型。DeepTrans以一种并行的方式将Transformer和CNN结合在一起,利于全局特征与局部特征的有效捕获。通过引入Transformer来增强图像中信息的远距离依赖关系,提高了作物全局信息的提取能力;加入通道注意力机制和空间注意力机制加强Transformer对通道信息的敏感度及ASPP(atrous spatial pyramid pooling)对作物空间信息捕获能力。实验结果表明,DeepTrans模型在MIoU指标上可达0.812,相较于Deeplab v3+模型提高了3.9%,该模型在五类作物的分类中精度均有提升,对于容易错分的甘蔗、玉米和香蕉三种作物,其IoU分别提高了2.9%、4.7%、13%。由此可见,DeepTrans模型在农作物分类图像的内部填充和全局预测方面有着更好的分割效果,有助于更准确地监测农田作物的种植结构及规模。 展开更多
关键词 农作物分类 无人机影像 Deeplab v3+ TRANSFORMER 注意力机制
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基于v3洋葱域名的比特币地址威胁程度分析
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作者 胡锦枫 徐晓瑀 +1 位作者 陈云芳 张伟 《计算机工程》 CAS CSCD 北大核心 2024年第3期173-181,共9页
比特币可以在不透露使用者身份的情况下进行交换,导致其成为不法分子在暗网上进行违法活动的主要方式。为了追踪比特币非法交易,传统方法根据比特币的伪匿名性,在整个区块链上进行启发式地址聚类,没有充分利用比特币地址在暗网上的信息... 比特币可以在不透露使用者身份的情况下进行交换,导致其成为不法分子在暗网上进行违法活动的主要方式。为了追踪比特币非法交易,传统方法根据比特币的伪匿名性,在整个区块链上进行启发式地址聚类,没有充分利用比特币地址在暗网上的信息。2021年Tor官方全面启用v3洋葱域名,使得以往的v2洋葱域名数据无法再作为分析的依据。设计并实现基于v3洋葱域名的比特币地址威胁程度的一体化分析框架TLAFDB。信息收集模块使用境外服务器解决地域限制并设置socks5h代理以支持暗网爬虫运行,使用洋葱种子地址在暗网中爬行收集最新的v3洋葱域名数据,信息清洗模块采用可同时覆盖Base58和Bech32编码的正则表达式以提取v3洋葱域名网页中的比特币地址,通过区块链搜索引擎Blockchain.com筛选存在真实交易的比特币地址,并建立其和所在v3洋葱域名的关联关系,信息分析模块采用人工分析和关键词匹配相结合的方法分类v3洋葱域名,赋予其关联的比特币地址类别和流行度并判定威胁程度。实验结果表明,TLAFDB收集了23627个v3洋葱域名网页,提取并分析1141个存在真实交易的比特币地址的类别、流行度和威胁程度,发现在暗网中同一个比特币地址常出现在大量的镜像洋葱域名网页上,超过95%的比特币地址被恶意使用,并且庞氏骗局交易量占高危比特币地址总交易量的99%。 展开更多
关键词 暗网 爬虫 v3洋葱域名 比特币地址 分类
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基于改进MobileNet v3的苹果叶片病害识别方法及移动端应用
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作者 张风伟 朱成杰 朱洪波 《江苏农业科学》 北大核心 2024年第7期205-213,共9页
准确识别苹果叶片病害种类以进行及时防治对于苹果增量增产具有重要的意义,为实现在移动设备实时对苹果叶片进行病害识别,提高苹果的产量,减少种植者的损失。首先收集了黑星病、斑点落叶病、锈病、白粉病、混合病、褐斑病等6种苹果叶部... 准确识别苹果叶片病害种类以进行及时防治对于苹果增量增产具有重要的意义,为实现在移动设备实时对苹果叶片进行病害识别,提高苹果的产量,减少种植者的损失。首先收集了黑星病、斑点落叶病、锈病、白粉病、混合病、褐斑病等6种苹果叶部病害和健康叶片的图像,并使用Retinex算法对图像进行数据增强,以提高数据集质量,然后将数据集按照8∶1∶1的比例划分为训练集、验证集和测试集;其次对MobileNet v3网络模型进行改进优化调整,在精简网络结构的同时减少冗余参数,并在非线性激活层后加入批归一化层,以提高网络的特征提取能力;同时,为了提升在低精度移动设备上的准确性和模型运行效率,将全连接层中的激活函数替换为ReLU6函数;最后,在模型训练时使用动量随机梯度下降优化器来进行模型权重系数的寻优,以减少训练时间和达到更高的分类准确率。试验结果表明,改进后的MobileNet v3-A3网络对苹果叶片病害图像的识别准确率为96.48%,模型权重为2.98 MB,识别速率为8.82 ms/幅图片,与其他同量级卷积神经网络相比识别精度更高、模型更小、识别速度更快。本研究使用Android Studio将权重模型封装到安卓软件中,实现了移动设备对苹果叶片病害的准确快速识别。 展开更多
关键词 苹果 叶部病害 图像识别 MobileNet v3 ANDROID
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基于改进YOLO v3的轴承端面缺陷检测算法
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作者 余浪 苗鸿宾 +1 位作者 苏赫朋 申光鹏 《机床与液压》 北大核心 2024年第9期209-214,共6页
为提高轴承端面缺陷检测的速度以及检测精度,提出一种基于改进YOLO v3的轴承端面缺陷检测算法。首先,对图像数据集进行数据增强处理以防止产生过拟合现象;其次,通过改进K-means聚类算法重新聚类出目标检测的Anchor Boxes,并引入SKNet注... 为提高轴承端面缺陷检测的速度以及检测精度,提出一种基于改进YOLO v3的轴承端面缺陷检测算法。首先,对图像数据集进行数据增强处理以防止产生过拟合现象;其次,通过改进K-means聚类算法重新聚类出目标检测的Anchor Boxes,并引入SKNet注意力机制模块对原网络结构以及输出层结构进行改进;最后对改进的YOLO v3算法进行实验验证,并与原YOLO v3算法进行对比分析。结果表明,改进后的YOLO v3算法相比原YOLO v3算法对轴承端面缺陷检测的mAP值提升了7.03%,检测速度提升了34.7帧/s,验证了改进算法的有效性。 展开更多
关键词 轴承 YOLO v3算法 缺陷检测 聚类算法
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CXCR4通过integrinαVβ3调控头颈部鳞癌细胞迁移的机制研究
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作者 常艳艳 李鹏 +1 位作者 孟金平 陈艳艳 《现代肿瘤医学》 CAS 北大核心 2023年第9期1584-1588,共5页
目的:研究C-X-C型趋化因子受体4(CXCR4)-整合素αVβ3(integrinαVβ3)介导头颈部鳞癌细胞迁移的分子生物学机制。方法:应用头颈部鳞癌细胞株HN-5,采用慢病毒转染方法构建CXCR4过表达的细胞株,用荧光显微镜观察基因表达情况;采用脂质体... 目的:研究C-X-C型趋化因子受体4(CXCR4)-整合素αVβ3(integrinαVβ3)介导头颈部鳞癌细胞迁移的分子生物学机制。方法:应用头颈部鳞癌细胞株HN-5,采用慢病毒转染方法构建CXCR4过表达的细胞株,用荧光显微镜观察基因表达情况;采用脂质体法将CXCR4-siRNA、integrinαVβ3-siRNA分别转染至HN-5细胞和CXCR4过表达的HN-5细胞中,Transwell小室实验检测HN-5细胞迁移能力,Western blot实验检测CXCR4、integrinαVβ3、基质金属蛋白酶-9(MMP-9)、基质金属蛋白酶-2(MMP-2)和黏附斑激酶(FAK)-非受体型酪氨酸蛋白激酶(SRC)-细胞外信号调节激酶(ERK)信号通路相关蛋白的表达情况。结果:CXCR4过表达可上调HN-5细胞中integrinαVβ3表达水平,而抑制CXCR4表达可下调integrinαVβ3表达;CXCR4过表达可调控MMP-2和MMP-9促进癌细胞迁移,并激活FAK-SRC-ERK信号通路;而抑制integrinαVβ3表达可明显逆转CXCR4过表达对HN-5细胞的上述作用。结论:CXCR4过表达可通过integrinαVβ3促进头颈部鳞癌细胞迁移,其作用机制可能与激活FAK-SRC-ERK通路有关。 展开更多
关键词 CXCR4 integrinα3 头颈部鳞癌 细胞迁移
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基于Kinect V2和Unity3D的机械臂人机交互系统
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作者 李子良 李庆党 +1 位作者 王晓波 和学泰 《计算机与数字工程》 2024年第3期735-739,745,共6页
针对人机交互方式存在不直观、操作复杂等问题,论文利用手部追踪技术开发出一种基于Kinect V2和Unity3D的人机交互系统,用户可以直接挥动手部就可以控制机械臂运动,交互方式更加简单、直观和灵活。该系统是通过Kinect V2来获得手部移动... 针对人机交互方式存在不直观、操作复杂等问题,论文利用手部追踪技术开发出一种基于Kinect V2和Unity3D的人机交互系统,用户可以直接挥动手部就可以控制机械臂运动,交互方式更加简单、直观和灵活。该系统是通过Kinect V2来获得手部移动轨迹来实现手部追踪,并在Unity3D平台上进行交互系统的开发。利用FABRIK算法和贝塞尔曲线分别实现了逆运动学求解和运动路径的记录,通过C#编写所需的脚本功能并开发出了两种交互模式,分别为实时控制模式和示教模式,两种模式均可通过UI面板进行选择。最后对两种模式分别进行实验,实验结果证明了该系统的可行性。 展开更多
关键词 人机交互 手部追踪 Kinect v2 UNITY3D
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Impacts of PI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions
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作者 Ramón Pérez-Núñez María Fernanda González +1 位作者 Ana María Avalos Lisette Leyton 《Neural Regeneration Research》 SCIE CAS 2025年第4期1031-1041,共11页
Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic ... Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,respectively.However,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries.Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their reactivity.Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune response.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo results.In astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses.Here,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation.We highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and Notch/PI3K/AKT pathways.While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial outcomes.This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation.The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior.The findings should then be validated using in vivo models to ensure real-life relevance.The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage,although further studies are required to fully comprehend its role due to varying factors such as different cell types,astrocyte responses to inflammation,and disease contexts.Specific strategies are clearly necessary to address these variables effectively. 展开更多
关键词 inflammation integrinS NEUROPROTECTIvE NEUROTOXIC phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)
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Co8W6Mo5Cr4V3粉末高速钢的热变形行为
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作者 杨礼林 陈学敏 +1 位作者 陈朔 赵莉萍 《粉末冶金材料科学与工程》 2024年第1期11-19,共9页
采用熔炼、电渣重熔和气雾化法制备Co8W6Mo5Cr4V3粉末,再通过热等静压制备Co8W6Mo5Cr4V3粉末高速钢。在不同变形条件下进行热压缩实验,研究粉末高速钢的热变形行为,根据获得的应力-应变曲线,建立热变形本构方程,绘制热加工图。结果表明:... 采用熔炼、电渣重熔和气雾化法制备Co8W6Mo5Cr4V3粉末,再通过热等静压制备Co8W6Mo5Cr4V3粉末高速钢。在不同变形条件下进行热压缩实验,研究粉末高速钢的热变形行为,根据获得的应力-应变曲线,建立热变形本构方程,绘制热加工图。结果表明:Co8W6Mo5Cr4V3粉末高速钢的流变应力随变形温度升高或应变速率减小而减小;通过本构方程预测的流变应力和实验得到的流变应力间的相关系数为0.995,可用此方程对粉末高速钢在不同变形条件下的应力进行预测;根据热加工图,粉末高速钢最优的变形温度为1 100~1 150℃,应变速率为0.1~1.0 s^(-1)。 展开更多
关键词 Co8W6Mo5Cr4v3 粉末高速钢 热变形 本构方程 热加工图
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Defect engineering on BiFeO_(3) through Na and V codoping for aqueous Na-ion capacitors
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作者 Wenyun Wang Chao Yang +4 位作者 Shangjing Yu Daotong Han Wentao Qi Rui Ling Guangqiang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期453-463,I0011,共12页
Sodium with low cost and high abundance is considered as a substitute element of lithium for batteries and supercapacitors,which need the appropriate host materials to accommodate the relatively large Na^(+) ions.Comp... Sodium with low cost and high abundance is considered as a substitute element of lithium for batteries and supercapacitors,which need the appropriate host materials to accommodate the relatively large Na^(+) ions.Compared to Li^(+) storage,Na^(+) storage makes higher demands on the structural optimization of perovskite bismuth ferrite(BiFeO_(3)).We propose a novel strategy of defect engineering on BiFeO_(3) through Na and V codoping for high-efficiency Na^(+) storage,to reveal the roles of oxygen vacancies and V ions played in the enhanced electrochemical energy storage performances of Na-ion capacitors.The formation of the oxygen vacancies in the Na and V codoped BiFeO_(3)(denoted as NV-BFO),is promoted by Na doping and suppressed by V doping,which can be demonstrated by XPS and EPR spectra.By the first-principles calculations,the oxygen vacancies and V ions in NV-BFO are confirmed to substantially lower the Na^(+)migration energy barriers through the space and electric field effects,to effectively promote the Na^(+) transport in the crystals.Electrochemical kinetic analysis of the NV-BFO//NV-BFO capacitors indicates the dominant capacitive-controlled capacity,which depends on fast Na^(+) deintercalation-intercalation process in the NV-BFO electrode.The NV-BFO//NV-BFO capacitors open up a new avenue for developing highperformance Na-ion capacitors. 展开更多
关键词 BiFeO_(3) Na^(+) storage v doping Oxygen vacancy CAPACITOR
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粘附分子CD44V6及Integrinαvβ_3在胆囊癌中的表达及意义
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作者 肖元新 马清涌 《中国现代医药杂志》 2012年第1期23-26,共4页
目的研究粘附分子CD44V6及Integrinαvβ_3在胆囊癌组织及胆囊炎中表达是否存在统计学意义的差异,其表达量与胆囊癌的分化程度之间的关系。方法应用免疫组织化学的方法检测20例胆囊癌及20例慢性胆囊炎组织中CD44V6及Integrinαvβ_3的表... 目的研究粘附分子CD44V6及Integrinαvβ_3在胆囊癌组织及胆囊炎中表达是否存在统计学意义的差异,其表达量与胆囊癌的分化程度之间的关系。方法应用免疫组织化学的方法检测20例胆囊癌及20例慢性胆囊炎组织中CD44V6及Integrinαvβ_3的表达,结合临床病理结果进行分析。结果在胆囊癌中CD44V6和Integrinαvβ_3表达阳性率分别为80.0%和70.0%。CD44V6及Integrinαvβ_3在胆囊癌中表达存在协同性,与胆囊癌分化程度呈正相关(均P<0.05)。结论 CD44V6及Integrinαvβ_3在胆囊癌中高表达(显著高于对照组),并且随着胆囊癌的分化程度降低其表达阳性分值增高;CD44V6及Integrinαvβ_3的表达与原发性胆囊癌的良恶性及分化程度相关;在相同标本中,CD44V6高表达往往伴有Integrinαvβ_3高表达,在胆囊癌的诊断上具有一致性,可联合作为临床监测胆囊癌发生、转移的参考指标。 展开更多
关键词 胆囊癌 CD44v6 integrinα_3
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新课标导向下的五年级下学期3v3篮球大单元教学设计方案
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作者 胡立锋 丁显锋 窦亚晨 《体育教学》 2024年第2期64-65,共2页
本文为五年级下学期3v3篮球大单元学习方案,以“篮球基本技术”为大概念引领整个单元教学。教学设计围绕核心素养培育、“教会、勤练、常赛”等理念,教学过程中以“移动技术、传球、运球、投篮、突破、篮球基础配合”等基本技术为大任... 本文为五年级下学期3v3篮球大单元学习方案,以“篮球基本技术”为大概念引领整个单元教学。教学设计围绕核心素养培育、“教会、勤练、常赛”等理念,教学过程中以“移动技术、传球、运球、投篮、突破、篮球基础配合”等基本技术为大任务驱动整个单元教学,单元学习过程中为学生创设各类比赛的真实情境,提高学生运用篮球基本技术的能力。最终,通过多种形式的“学、练、赛”提高学生的篮球水平,培育学生的核心素养。 展开更多
关键词 新课标 五年级 3v3篮球 大单元
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蝴蝶兰‘V3’切花栽培管理及采收技术规程
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作者 徐金凤 岳李心 +1 位作者 孙勇 董小艳 《花卉》 2024年第4期1-3,共3页
国内蝴蝶兰‘V3’切花的规模化、专业化生产起步较晚。为了更好地满足市场对高品质蝴蝶兰切花的需求,提高生产标准化程度,结合连云港实际生产情况,对蝴蝶兰‘V3’切花的栽培和采收技术进行了全面总结。以期为推动国内蝴蝶兰切花生产的... 国内蝴蝶兰‘V3’切花的规模化、专业化生产起步较晚。为了更好地满足市场对高品质蝴蝶兰切花的需求,提高生产标准化程度,结合连云港实际生产情况,对蝴蝶兰‘V3’切花的栽培和采收技术进行了全面总结。以期为推动国内蝴蝶兰切花生产的进一步发展提供参考依据。 展开更多
关键词 蝴蝶兰 v3 切花
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