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排序方式: 共有462条查询结果,搜索用时 15 毫秒
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Andreja Erman Urka Kamenek Urka Dragin Jerman Mojca Pavlin Maja emaar Peter Verani
Rok Romih 《International journal of molecular sciences》2021,22(12)
Non-muscle-invasive bladder cancer is the most common form of bladder cancer. The main problem in managing bladder tumors is the high recurrence after the transurethral resection of bladder tumors (TURBT). Our study aimed to examine the fate of intravesically applied cancer cells as the implantation of cancer cells after TURBT is thought to be a cause of tumor recurrence. We established an orthotopic mouse bladder tumor model with MB49-GFP cancer cells and traced them during the first three days to define their location and contacts with normal urothelial cells. Data were obtained by Western blot, immunolabeling, and light and electron microscopy. We showed that within the first two hours, applied cancer cells adhered to the traumatized epithelium by cell projections containing α3β1 integrin on their tips. Cancer cells then migrated through the epithelium and on day 3, they reached the basal lamina or even penetrated it. In established bladder tumors, E-cadherin and desmoplakin 1/2 were shown as feasible immunohistochemical markers of tumor margins based on the immunolabeling of various junctional proteins. Altogether, these results for the first time illustrate cancer cell implantation in vivo mimicking cellular events of tumor recurrence in bladder cancer patients. 相似文献
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This paper describes the design and application of the Atmospheric Evaluation and Research Integrated model for Spain (AERIS). Currently, AERIS can provide concentration profiles of NO2, O3, SO2, NH3, PM, as a response to emission variations of relevant sectors in Spain. Results are calculated using transfer matrices based on an air quality modelling system (AQMS) composed by the WRF (meteorology), SMOKE (emissions) and CMAQ (atmospheric-chemical processes) models. The AERIS outputs were statistically tested against the conventional AQMS and observations, revealing a good agreement in both cases. At the moment, integrated assessment in AERIS focuses only on the link between emissions and concentrations. The quantification of deposition, impacts (health, ecosystems) and costs will be introduced in the future. In conclusion, the main asset of AERIS is its accuracy in predicting air quality outcomes for different scenarios through a simple yet robust modelling framework, avoiding complex programming and long computing times. 相似文献
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目的 针对传统基于混沌系统的图像加密算法在加密遥感图像时存在速度差、安全性不足等问题,提出一种混沌系统和脱氧核糖核酸(deoxyribonucleic acid,DNA)编码的并行遥感图像加密算法,提升图像加密的效率和安全性。方法 利用明文图像的安全散列算法256(secure Hash algorithm 256,SHA-256)哈希值修改混沌系统的参数和初始值,提高算法的明文敏感性,并通过2维Hénon-Sine映射置乱图像,打乱像素之间的分布规律;然后利用图形处理器(graphics processing unit,GPU)并行计算密钥序列,缩短加密时间,通过选择多个高维混沌系统和修改混沌系统初始值确保密钥序列的随机性;最后利用密钥序列和GPU对图像进行DNA并行加密,得到最终的密文图像。在DNA并行加密过程中,生成一种DNA-S盒,对DNA编码进行非线性替换。结果 在遥感图像以及普通彩色图像上的仿真实验和安全性分析结果表明,本文算法在加密遥感图像上速度达到80 Mbit/s以上,密钥空间大于10200,信息熵趋近于8,密文图像直方图平坦均匀,且通过了美国国家标准与技术研究院(National Institute of Standards and Technology,NIST)随机测试以及卡方检验;与其他算法相比,本文算法在密钥空间、相邻像素相关性、像素改变率(number of changing pixel rate,NPCR)、统一平均变化强度(unified averaged changed intensity,UACI)和信息熵等评价指标上更接近理想值。结论 本文算法在大幅提升加密速度的同时,保证算法足够安全,能够抵抗各种攻击,适合遥感图像以及大容量图像的保密存储和网络传输。 相似文献
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The flow stress features of MB26 magnesium alloy were studied by isothermal compression at 300-450 ℃ and strain rate of 0.001^-1 s J with Gleeble 1500 thermal simulator. In addition, the deformation activation energy Q was calculated. The results show that the strain rate and deformation temperature have obvious effect on the true stress. The peak value of flow stress becomes larger with increasing strain rate at the same temperature, and gets smaller with the increasing deformation temperature at the same strain rate. The alloy shows partial dynamic recrystallization. The flow stress of MB26 magnesium alloy during high temperature deformation can be represented by Zener-Hollomon parameter including the Arrhemius term. The temperatt, re range of 350-400℃ is suggested for hot-forming of this alloy. 相似文献
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王洋 《计算机光盘软件与应用》2011,(15)
以首都机场信息系统集成项目为背景,本文主要介绍了基于SOA架构的首都机场中间件平台的设计与实现,以及通过该平台实现的业务标准、数据标准的统一以及硬件平台的整合。 相似文献
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In the current circumstance, e-commerce through an online banking system plays a significant role. Customers may either buy goods from E-Commerce websites or use online banking to move money to other accounts. When a user participates in these types of behaviors, their sensitive information is sent to an untrustworthy network. As a consequence, when transmitting data from an internal browser to an external E-commerce web server using the cryptographic protocol SSL/TLS, the E-commerce web server ensures the security of the user’s data. The user should be pleased with the confidentiality, authentication, and authenticity properties of the SSL/TLS on both the user’s web browser and the remote E-commerce web server. E-Commerce web servers should choose the best SSL/TLS cipher suites for negotiating the user in order to attain such optimistic scenarios, as the cipher suite used in SSL/TLS plays an important role in securing E-Commerce web servers. The paper primarily focuses on analyzing the SSL/TLS cipher and elliptic curves. The paper also recommends the best elliptic curve cipher suites for E-Commerce and online banking servers, based on their power consumption, handshake execution time, and key exchange and signature verification time. 相似文献
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字符叠加(0sD)是一种在视频电子信号中叠加字符信息,使得电视图像中叠加有字符或汉字图形的技术。目前这项技术的应用极其广泛,因此,针对这种需求,结合市场最新技术对实现视频字符叠加进行研究与设计。文章论述了视频字符叠加的原理,并描述了目前市场上流行的叠加芯片的技术指标,就不同的芯片的不同的方案提出分析论证:着重了解MB90092、UPD6453和MAX7456方案的特性与使用方法。 相似文献