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21.
22.
简述了远程监控系统的发展和技术要求,并基于目前流行的H.264编码格式和RTP协议探讨了远程监控的网络管理模块的视频传输与控制设计思路和方案. 相似文献
23.
视频会议的发展1.视频会议与电视会议视频会议是通过终端与网络,使身处异地的与会者就同一议题参与讨论,相互之间不仅可以听到发言者声音、图像及背景,同时还可以进行数据、文字、图表的交流。它利用视频、音频压缩技术及点到点或点到多点的通信规程、帧同步控制和指示信号等技术设备,通过不同的传输信道进行码流的传送。通常把视频会议也称为会议电视。其实,视频会议只是电视会议最主要的应用领域,会议电视还包括远程教育系统、远程监控系统、视频点播以及电子商务等。视频会议系统在用户组成模式上分为点对点和群组视频会议系统,按技术实… 相似文献
24.
Carlos Garcia-Padilla Estefanía Lozano-Velasco María del Mar Muoz-Gallardo Juan Manuel Castillo-Casas Sheila Cao-Carrillo Francisco Jos Martínez-Amaro Virginio García-Lpez Amelia Arnega Diego Franco Virginio García-Martínez Carmen Lpez-Snchez 《International journal of molecular sciences》2022,23(15)
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma. 相似文献
25.
Yong Li Yanyan Zhang Andrew Walayat Yingjie Fu Bailin Liu Lubo Zhang Daliao Xiao 《International journal of molecular sciences》2022,23(13)
Nicotine exposure either from maternal cigarette smoking or e-cigarette vaping is one of the most common risk factors for neurodevelopmental disease in offspring. Previous studies revealed that perinatal nicotine exposure programs a sensitive phenotype to neonatal hypoxic-ischemic encephalopathy (HIE) in postnatal life, yet the underlying mechanisms remain undetermined. The goal of the present study was to determine the regulatory role of H19/miR-181a/ATG5 signaling in perinatal nicotine exposure-induced development of neonatal brain hypoxic-ischemic sensitive phenotype. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps. All experiments were conducted in offspring pups at postnatal day 9 (P9). Perinatal nicotine exposure significantly enhanced expression of miR-181a but attenuated autophagy-related protein 5 (ATG5) mRNA and protein levels in neonatal brains. Of interest, miR-181a mimicking administration in the absence of nicotine exposure also produced dose-dependent increased hypoxia/ischemia (H/I)-induced brain injury associated with a decreased ATG5 expression, closely resembling perinatal nicotine exposure-mediated effects. Locked nucleic acid (LNA)-miR-181a antisense reversed perinatal nicotine-mediated increase in H/I-induced brain injury and normalized aberrant ATG5 expression. In addition, nicotine exposure attenuated a long non-coding RNA (lncRNA) H19 expression level. Knockdown of H19 via siRNA increased the miR-181a level and enhanced H/I-induced neonatal brain injury. In conclusion, the present findings provide a novel mechanism that aberrant alteration of the H19/miR-181a/AGT5 axis plays a vital role in perinatal nicotine exposure-mediated ischemia-sensitive phenotype in offspring and suggests promising molecular targets for intervention and rescuing nicotine-induced adverse programming effects in offspring. 相似文献
26.
食用油碟式分离机碟片的渗氮激光相变硬化复合处理研究 总被引:1,自引:1,他引:0
介绍了食用油碟式分离机碟片的常规表面处理方法,提出了渗氮激光相变硬化复合处理技术,通过硬度实验、耐磨性实验、抗腐蚀性实验及残余应力分布曲线,对实验结果进行了较深入的分析,得出渗氮激光相变硬化复合处理技术可提高4C r13钢碟片抗腐蚀能力和抗疲劳性能的结论。 相似文献
27.
TP347H与T91异种钢焊接性能分析 总被引:1,自引:0,他引:1
随着电站设备中金属部件使用钢材种类的逐渐增多,不可避免地会遇到异种钢焊接的问题.为此,通过对马氏体耐热钢(T91)和奥氏体钢(TP347H)的性能分析,详细阐述了T91 TP347H焊接存在的问题,探讨了T91与TP347H异种钢接头的焊接方法、焊接材料及焊接工艺要点. 相似文献
28.
Tatyana A. Vasilyeva Andrey V. Marakhonov Sergey I. Kutsev Rena A. Zinchenko 《International journal of molecular sciences》2022,23(12)
Genome-wide sequencing metadata allows researchers to infer bias in the relative frequencies of mutational events and to predict putative mutagenic models. In addition, much less data could be useful in the evaluation of the mutational frequency spectrum and the prevalent local mutagenic process. Here we analyzed the PAX6 gene locus for mutational spectra obtained in our own and previous studies and compared them with data on other genes as well as the whole human genome. MLPA and Sanger sequencing were used for mutation searching in a cohort of 199 index patients from Russia with aniridia and aniridia-related phenotypes. The relative frequencies of different categories of PAX6 mutations were consistent with those previously reported by other researchers. The ratio between substitutions, small indels, and chromosome deletions in the 11p13 locus was within the interval previously published for 20 disease associated genomic loci, but corresponded to a higher end due to very high frequencies of small indels and chromosome deletions. The ratio between substitutions, small indels, and chromosome deletions for disease associated genes, including the PAX6 gene as well as the share of PAX6 missense mutations, differed considerably from those typical for the whole genome. 相似文献
29.
VoIP电话的安全问题及防护措施 总被引:1,自引:0,他引:1
VoIP电话是综合了传统电信技术与计算机网络技术的一种新型应用。VoIP电话在传输时将信号压缩后封装成IP包,在IP网络上传输,这种传输方式存在着各种安全隐患。讨论了VoIP电话多种可能存在的安全问题,并就这些安全问题作了详细的分析,同时提出了防护措施,以最大限度地保障VoIP电话的安全。 相似文献
30.