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61.
Spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats that had been on a low sodium diet for 3 days were given 1.5 mmol sodium chloride kg-1 body weight either orally or intravenously. The rats receiving an oral sodium load showed a greater natriuresis than those receiving the same saline load intravenously. No increase of renal sodium excretion was observed when the rats received a hypertonic mannitol solution orally. The cumulative sodium excretion during the 8 h following oral loading was two to three times larger in SHR than in WKY, whereas no difference between strains could be demonstrated after giving saline intravenously. Furthermore, after switching from normal to low sodium diet the rate of decrease of renal sodium excretion was greater in SHR than in WKY rats. It is proposed that there exists a gastrointestinal sensory mechanism for sodium controlling the renal sodium excretion. Furthermore, it is suggested that the function of this mechanism differs between SHR and WKY. 相似文献
62.
异型材挤出口模内的流动模拟 总被引:10,自引:1,他引:9
本文根据挤出机理,对口模内的流动行为进行适当的简化和假定,建立了挤出口模内流动分析的数学模型,并采用横截面/假想区域法实现了复杂异型材挤出口模内的数值模拟,数值分析结果与三维有限元解和解析解的对比,取得了满意的效果。 相似文献
63.
RM Mu?oz LA Pulpón M Yebra J Segovia M San Martín C Salas 《Canadian Metallurgical Quarterly》1998,17(11):801-806
The fibrinolytic capacity of patients with acute myocardial infarction (AMI) is known to be impaired. The primary regulatory element of the fibrinolytic system is plasminogen activator inhibitor (PAI). It has been previously observed that there are 2 peaks in the plasma PAI level of AMI patients at 4h and 16h after thrombolytic therapy with recombinant tissue plasminogen activator (rtPA). Lanoteplase/SUN9216 is a mutant tPA with a biological half-life longer than that of rtPA. Thrombolytic therapy with mutant tPA or rtPA was carried out consecutively in 21 patients with AMI (8 patients as the mutant tPA group, and 13 patients as the rtPA group). The recanalization time of the mutant tPA group was significantly faster than that of the rtPA group (16.1 +/- 3.9 min vs 39.6 +/- 4.8 min, p<0.01). The PAI activity at 4h after the initiation of thrombolysis was significantly lower in the mutant tPA group than in the rtPA group (8.74 +/- 5.46IU/L vs 26.74 +/- 3.35 IU/L, p<0.01). There was a one mild peak in serial plasma PAI activity levels 24h after the initiation of thrombolysis. The results suggest that thrombolytic therapy with mutant tPA reduced the impairment of fibrinolytic capacity. The mutant tPA gives faster recanalization and lower PAI activity after successful thrombolysis, compared with rtPA. 相似文献
64.
三维立体成像及其应用 总被引:3,自引:0,他引:3
本文首先介绍了三种传统的主要三维立体成像方法,即透镜板三维成像方法,投影式三维显示和全息照相术,其次,重点对于采用计算机产生的三维立体景象的方法进行了综述,其中包括人们近年来研究较多的自动立体成像技术等,最后给出了三维立体成像技术在航空航天,工业,教育,医学,军事等领域的应用实例,并预测了三维立体成像技术今后的主要发展方向。 相似文献
65.
66.
Winner-Take-All (WTA) or K-Winner-Take-All (KWTA) networks have been frequently used as the basic building blocks of complex neural networks. This paper introduces a new selection rule for network connections that implements stable KWTA networks. To widen the applications of WTA networks, a new class of WTA networks is proposed, and their efficient design methods are presented. We demonstrate the properties of the generalized class of WTA networks, through three application examples. 相似文献
67.
本文研究了TiO2掺入对CaO稳定ZrO2(简称CaSZ-NiCr)金属陶瓷烧结特性的影响,测定了CaSZ-NiCr-TiO2金属陶瓷烧结样品的密度和显微硬度,结果表明,TiO2的掺入能提高CaSZ-NICr金属陶瓷的烧结密度和显微硬度,对CaSZ-NiCr金属陶瓷有助烧结作用.金相观察表明,TiO3的掺入改变了NiCr相在金属陶瓷中的形貌,说明了NiCr与CaSZ的浸润性有一定的改善.XRD和EPMA分析结果显示,TiO2偏聚在NiCr金属相中,不影响CaSZ的稳定性. 相似文献
68.
Jiaming Mao Mingming Zhang Mu Chen Lu Chen Fei Xia Lei Fan ZiXuan Wang Wenbing Zhao 《计算机系统科学与工程》2021,39(3):373-390
The rapidly increasing popularity of mobile devices has changed the methods with which people access various network services and increased network traffic markedly. Over the past few decades, network traffic identification has been a research hotspot in the field of network management and security monitoring. However, as more network services use encryption technology, network traffic identification faces many challenges. Although classic machine learning methods can solve many problems that cannot be solved by port- and payload-based methods, manually extract features that are frequently updated is time-consuming and labor-intensive. Deep learning has good automatic feature learning capabilities and is an ideal method for network traffic identification, particularly encrypted traffic identification; Existing recognition methods based on deep learning primarily use supervised learning methods and rely on many labeled samples. However, in real scenarios, labeled samples are often difficult to obtain. This paper adjusts the structure of the auxiliary classification generation adversarial network (ACGAN) so that it can use unlabeled samples for training, and use the wasserstein distance instead of the original cross entropy as the loss function to achieve semisupervised learning. Experimental results show that the identification accuracy of ISCX and USTC data sets using the proposed method yields markedly better performance when the number of labeled samples is small compared to that of convolutional neural network (CNN) based classifier. 相似文献
69.
Muñoz-Montoro A. J. Suarez-Dou D. Cortina R. Canadas-Quesada F. J. Combarro E. F. 《The Journal of supercomputing》2021,77(8):8135-8150
The Journal of Supercomputing - In this paper, we propose a parallel source separation system designed to extract heart and lung sounds from single-channel mixtures. The proposed system is based on... 相似文献
70.
Neural Computing and Applications - In this paper, one concerns with the problem of trajectory tracking control for an underactuated unmanned surface vehicle subject to uncertain dynamics and input... 相似文献