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Gas stunning with CO_2 affected meat color,lipid peroxidation, oxidative stress, and gene expression of mitogen-activated protein kinases, glutathione S-transferases,and Cu/Zn-superoxide dismutase in the skeletal muscles of broilers 被引量:5
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作者 Lei Xu Haijun Zhang +4 位作者 Hongyuan Yue Shugeng Wu Haiming Yang Zhiyue Wang Guanghai Qi 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第3期738-749,共12页
Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the ... Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS. 展开更多
关键词 Antioxidant enzyme Broiler Controlled atmosphere stunning GAS stunning Lipid PEROXIDATION MAPK/Nrf2/ARE Meat color Oxidative stress
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Investigation of Myocardial Stunning after Cardiopulmonary Resuscitation in Pigs 被引量:8
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作者 YANGLin LI ChunSheng +3 位作者 GAO ChunJin WANG Shuo JI XianFei SU ZhiYu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第2期155-162,共8页
Objective To investigate cardiac function and myocardial perfusion during 48 h after cardiopulmonary resuscitation (CPR), further to test myocardial stunning and seek indicators for long‐term survival after CPR. Me... Objective To investigate cardiac function and myocardial perfusion during 48 h after cardiopulmonary resuscitation (CPR), further to test myocardial stunning and seek indicators for long‐term survival after CPR. Methods After 4 min of untreated ventricular fibrillation, fifteen anesthetized pigs were studied at baseline and 2 h, 4 h, 24 h, and 48 h after restoration of spontaneous circulation (ROSC). Hemodynamic data, echocardiography and gated‐single photon emission computed tomography myocardial perfusion images were carried out. Results Mean arterial pressure (MAP), coronary perfusion pressure (CPP) and cardiac troponin I (CTNI) showed significant differences between eventual survival animals and non‐survival animals at 4 h after ROSC (109.2±10.7 mmHg vs. 94.8±12.3 mmHg, P=0.048; 100.8±6.9 mmHg vs. 84.4±12.6 mmHg, P=0.011; 1.60±0.13 ug/L vs. 1.75±0.10 ug/L, P=0.046). Mitral valve early‐to‐late diastolic peak velocity ratio, mitral valve deceleration time recovered 24 h; ejection faction and the summed rest score recovered 48 h after ROSC. Conclusion Cardiac systolic and early active relaxation dysfunctions were reversible within survival animals; cardiac stunning might be potentially adaptive and protective after CPR. The recovery of MAP, CPP, and CTNI could be the indicators for long‐term survival after CPR. 展开更多
关键词 Myocardial stunning Systolic and diastolic dysfunctions Cardiopulmonary resuscitation
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Mechanisms of Myocardial Stunning in Stress-Induced Cardiomyopathy
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作者 Quanwei Pei Nadine Mbabazi +8 位作者 Lina Zou Junpei Zhang Hongpeng Yin Bin Li Jiaxin Wang Weifa Wang Pengqi Lin Junjie Yang Dechun Yin 《Cardiovascular Innovations and Applications》 2022年第3期1-7,共7页
Stress-induced cardiomyopathy,in contrast to acute myocardial infarction,is a type of acute heart failure characterized by reversible left ventricular dysfunction.Cardiac imaging primarily reveals left ventricle myoca... Stress-induced cardiomyopathy,in contrast to acute myocardial infarction,is a type of acute heart failure characterized by reversible left ventricular dysfunction.Cardiac imaging primarily reveals left ventricle myocardial stunning,81.7%of which is apical type.Emotional or psychological stress usually precedes the onset of stress-induced cardiomyopathy,which is increasingly being recognized as a unique neurogenic myocardial stunning disease.To distinguish between acute myocardial infarction and acute viral or auto-immune myocarditis,this review summarizes specific mechanisms of myocardial stunning in stress-induced cardiomyopathy,such as calcium disorders,metabolic alterations,anatomical and histological variations in different parts of the left ventricle,and microvascular dysfunction. 展开更多
关键词 Stress-induced cardiomyopathy Myocardial stunning Calcium disorders Metabolic alterations Coronary microvascular dysfunction
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Hypoglycemic myocardial stunning as cause of cardiogenic shock in a patient with ischemic cardiomyopathy: A case report and review of literature
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作者 Khawar Maqsood Ghazi Mirrani +3 位作者 Nosheen Sarwar Amatur R. Amarah Muhammad Rizwan Sardar Timothy A. Shapiro 《Case Reports in Clinical Medicine》 2013年第1期89-92,共4页
Hypoglycemia is a common complication seen in patients with diabetes mellitus and has been proven to have adverse effects on cardiovascular mortality. Hypoglycemia can potentially lead to worsening of cardiac function... Hypoglycemia is a common complication seen in patients with diabetes mellitus and has been proven to have adverse effects on cardiovascular mortality. Hypoglycemia can potentially lead to worsening of cardiac function in patients with ischemic heart disease. We present a case of cardiogenic shock in a patient with hypoglycemia secondary to insulin accumulation due to worsening renal function with dramatic recovery of shock once his sugars normalized. 展开更多
关键词 Chronic Heart Failure HYPOGLYCEMIA Myocardial stunning ISCHEMIC CARDIOMYOPATHY CARDIOGENIC Shock
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Predictors of left atrial appendage stunning after electrical cardioversion of non-valvular atrial fibrillation 被引量:5
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作者 杨沙宁 黄从新 +3 位作者 胡晓军 金立军 李凤翥 彭水先 《Chinese Medical Journal》 SCIE CAS CSCD 2003年第10期1445-1450,共6页
Objective To identify predictors of left atrial appendage stunning after the use of electrical cardioversion to restore sinus rhythm in patients with non-valvular atrial fibrillation. Methods A total of 68 consecutive... Objective To identify predictors of left atrial appendage stunning after the use of electrical cardioversion to restore sinus rhythm in patients with non-valvular atrial fibrillation. Methods A total of 68 consecutive patients (45 men,23 women,60.5±8.7 years of age) with non-valvular atrial fibrillation undergoing electrical cardioversion were enlisted in this study. Clinical and echocardiographic variables were analyzed by univariate regression and multivariate logistic regression to investigate the relationship between occurrences of left atrial appendage stunning and these factors. Results Univariate analysis revealed that,in comparing patients without and with left atrial appendage stunning,there were significant differences in the duration of atrial fibrillation > 8 weeks (32.3% vs 75.5%,P <0.001),left atrial diameter > 50 mm (29.0% vs 54.1%,P <0.05),left atrial emptying fraction (31.5%±7.8% vs 27.1%±8.5%,P <0.05),left ventricular ejection fraction < 50% (38.7% vs 67.6%,P <0.05),maximum electrical energy (96.8 J±65.8 J vs 156.8 J±100.8 J,P <0.01),cumulative electrical energy 146.8 J±142.6 J vs 290.5 J±242.1 J, P <0.01) and number of electrical cardioversion shocks (1.7±0.9 vs 2.43±1.20,P <0.05). However,backward stepwise multivariate logistic regression analysis identified as significant and independent predictors of left atrial appendage stunning only duration of atrial fibrillation > 8 weeks (OR=7.249,95%CI=1.998-26.304, P <0.01),left atrial diameter > 50 mm (OR=3.896,95%CI=1.105-13.734,P <0.05),left ventricular ejection fraction < 50% (OR=4.465,95%CI=1.51713.140, P <0.01) and cumulative energy of electrical cardioversion (OR=1.004,95%CI=1.000-1.008, P <0.05). Conclusions Duration of atrial fibrillation >8 weeks,left atrial diameter >50 mm,left ventricular ejection fraction <50%,and cumulative energy of electrical cardioversion are independent predictors of left atrial appendage stunning. Anticoagulation treatment should be individualized for patients undergoing electrical cardioversion to reduce the risk of both cardioversion-related thromboembolic events and hemorrhagic complications caused by warfarin treatment. 展开更多
关键词 myocardial stunning CARDIOVERSION atrial fibrillation
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STUNNING GREENERY
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《Beijing Review》 2018年第28期16-17,共2页
In recent years,China has made considerable efforts toward ecological and environmental protection.The government has introduced a series of environmental protection laws and regulations targeting water,soil and air p... In recent years,China has made considerable efforts toward ecological and environmental protection.The government has introduced a series of environmental protection laws and regulations targeting water,soil and air pollution,with signs of progress evident across the country. 展开更多
关键词 stunning GREENERY
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A STUNNING REGION
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《Beijing Review》 2011年第32期22-23,共2页
Xinjiang’s outstanding natural beauty—its azure lakes, rolling grasslands, rich valleys and stark deserts—gives it enormous tourist
关键词 A stunning REGION
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一种基于预测的Symmetric NAT穿越解决方案 被引量:10
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作者 王止戈 彭宇峰 +1 位作者 张苏灵 高传善 《计算机工程》 CAS CSCD 北大核心 2005年第11期122-123,210,共3页
NAT穿越技术是基于分组的多媒体传输技术中一个重要的研究课题。STUN方案可以较好地解决大多数情况下的NAT穿越问题,但是无法实现对对称型NAT的穿越。在STUN的基础上,提出了一种基于预测的解决方案P-STUN,可以实现对对称型NAT的穿越。... NAT穿越技术是基于分组的多媒体传输技术中一个重要的研究课题。STUN方案可以较好地解决大多数情况下的NAT穿越问题,但是无法实现对对称型NAT的穿越。在STUN的基础上,提出了一种基于预测的解决方案P-STUN,可以实现对对称型NAT的穿越。经过测试,P-STUN方案较好地达到了设计要求。 展开更多
关键词 网络地址转换 STUN P-STUN 命中率 临界时间
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基于ICE方式H.323信令穿越Symmetric NAT技术研究 被引量:6
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作者 陈晓铭 吴中福 陈蕾 《计算机科学》 CSCD 北大核心 2006年第8期82-85,共4页
基于IP的数据、语音、视频等业务在NGN网络中所面临的一个实际困难就是如何有效地穿越各种NAT/FW的问题。对此,H.323协议以往的解决方法有ALGs,STUN,TURN等方式。本文探讨了一种新的H.323信令穿越NAT/FW的解决方案—交互式连通建立方式(... 基于IP的数据、语音、视频等业务在NGN网络中所面临的一个实际困难就是如何有效地穿越各种NAT/FW的问题。对此,H.323协议以往的解决方法有ALGs,STUN,TURN等方式。本文探讨了一种新的H.323信令穿越NAT/FW的解决方案—交互式连通建立方式(ICE)。它通过综合利用现有协议,以一种更有效的方式来组织会话建立过程。并设计一个实例针对H.323信令协议穿越Symmetric NAT流程进行了描述,最后总结了ICE的优势及应用前景。 展开更多
关键词 SYMMETRIC NAT H.323 STUN TURN
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一种实现SIP穿越NAT的新方案 被引量:3
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作者 张波 胡瑞敏 边学工 《计算机工程》 CAS CSCD 北大核心 2005年第2期119-121,共3页
提出了一种使用STUN协议,只在应用层实现,无须改动现有NAT及SIP终端,无须扩展协议就可以让用UDP方式传输的SIP信令和媒体流顺利穿越大多数类型NAT设备的解决方案,并通过一个实例详细说明了这一方案的实现。
关键词 SIP 协议 信令 STUN 媒体流 NAT 传输 UDP 应用层 扩展
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一种解决SIP NAT的方案的设计与实现 被引量:5
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作者 许先斌 万庆 《计算机应用》 CSCD 北大核心 2004年第4期83-85,共3页
要让使用私有IP地址的用户通过SIP协议进行会话,就必须使SIP的信令流和媒体流穿越NAT,而其中的难点是媒体流的穿越。目前针对这个问题国内外提出了很多方法,有些已经形成了标准,但是这些方法都存在着一些缺陷,像最常用的STUN协议就无法... 要让使用私有IP地址的用户通过SIP协议进行会话,就必须使SIP的信令流和媒体流穿越NAT,而其中的难点是媒体流的穿越。目前针对这个问题国内外提出了很多方法,有些已经形成了标准,但是这些方法都存在着一些缺陷,像最常用的STUN协议就无法穿越同步NAT。文章在研究了这些方法的基础上提出了一种新的解决方案,其基本思想是把目前的一些方法综合起来使用使之能够避免单独使用所带来的缺陷,并详细叙述了具体的实现过程。 展开更多
关键词 SIP NAT STUN TURN
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一种面向物联网的M2M通信解决方案 被引量:7
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作者 王群 钱焕延 《微电子学与计算机》 CSCD 北大核心 2012年第11期13-17,共5页
在分析了M2M系统体系结构和工作原理的基础上,利用NAT穿越技术在物联网中的应用优势,提出了一种基于STUN和STUNT协议的、具有用户身份认证功能的M2M通信方案.经过实验测试,该方案不需要改变原有网络结构,只需要在M2M设备中嵌入STUN Cli... 在分析了M2M系统体系结构和工作原理的基础上,利用NAT穿越技术在物联网中的应用优势,提出了一种基于STUN和STUNT协议的、具有用户身份认证功能的M2M通信方案.经过实验测试,该方案不需要改变原有网络结构,只需要在M2M设备中嵌入STUN Client和STUNT Client模块,就能够实现物联网中不同M2M节点之间的通信与管理. 展开更多
关键词 M2M系统 网络地址转换(NAT) NAT穿越 STUN STUNT 通信
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一种SIP穿透NAT的解决方案 被引量:5
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作者 张正炳 王海波 李中年 《微计算机信息》 北大核心 2007年第04X期256-257,291,共3页
基于IP的语音、数据、视频等业务在NGN网络中所面临的一个实际困难就是如何有效地穿透各种NAT的问题。现有的解决方案有ALG、Media Proxy、STUN、Middlebox等。本文提出了一种综合应用STUN和Media Proxy方案解决SIP穿透NAT的方案。对于... 基于IP的语音、数据、视频等业务在NGN网络中所面临的一个实际困难就是如何有效地穿透各种NAT的问题。现有的解决方案有ALG、Media Proxy、STUN、Middlebox等。本文提出了一种综合应用STUN和Media Proxy方案解决SIP穿透NAT的方案。对于非对称NAT采用STUN穿透,对于对称NAT采用Media Proxy方案穿透。实验结果表明,该方案可以让SIP终端穿透几乎所有类型的NAT。 展开更多
关键词 会话初始化协议 媒体代理 STUN 网络地址转换 穿透
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H.323协议穿越NAT的方法研究及实现 被引量:1
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作者 汪志兵 崔慧娟 唐昆 《计算机应用研究》 CSCD 北大核心 2006年第6期242-244,共3页
分析了H.323协议在穿越NAT时遇到的几个主要问题,并对比了不同的解决方法,给出了一种相对可靠有效的解决方案;同时以OpenH.323和GNUGK为例,给出了具体的实现方法。
关键词 H.323 NAT NAPT STUN NAT穿越
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H.323信令与媒体流穿越NAT的通用方法 被引量:1
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作者 李中年 张正炳 《计算机工程与应用》 CSCD 北大核心 2006年第35期133-135,139,共4页
针对NAT对H.323通信造成的困难,提出了一种通用的穿越NAT的方案,此种方案针对所有类型的NAT,不需要修改NAT,只对H.323作小的修改,使处于NAT后的任意H.323终端都能自由通信,并尽可能地保证媒体流数据能直接送达对方,保证语言、视频质量,... 针对NAT对H.323通信造成的困难,提出了一种通用的穿越NAT的方案,此种方案针对所有类型的NAT,不需要修改NAT,只对H.323作小的修改,使处于NAT后的任意H.323终端都能自由通信,并尽可能地保证媒体流数据能直接送达对方,保证语言、视频质量,做到大容量。 展开更多
关键词 NAT H.323 STUN P2P 穿越
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对等系统NAT穿越技术研究 被引量:2
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作者 谢统义 黄保华 《广西教育学院学报》 2014年第3期145-148,共4页
计算机和智能手机作为终端进行对等网络通信时,通常是被NAT(network address translator)设备隔离的,阻碍现代智能网络应用的发展。本文对国内外NAT技术原理、NAT基本类型以及各种NAT技术进行分析,详细分析了常用NAT技术的应用环境和体... 计算机和智能手机作为终端进行对等网络通信时,通常是被NAT(network address translator)设备隔离的,阻碍现代智能网络应用的发展。本文对国内外NAT技术原理、NAT基本类型以及各种NAT技术进行分析,详细分析了常用NAT技术的应用环境和体系结构,以及其有效性、稳定性、健壮性、安全性等技术特点,为对等系统NAT穿越技术的研究提供基础。 展开更多
关键词 NAT STUN TURN 穿越
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网络地址转换器友好通讯构件的设计与实现 被引量:1
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作者 贺清碧 黄大荣 赵玲 《科学技术与工程》 北大核心 2016年第18期197-203,224,共8页
为了解决IPv4地址匮乏问题,网络中部署了大量的NAT设备,而NAT的部署破坏了Internet端到端的特性,并给不断发展的网络多媒体应用带来了障碍。针对该问题,提出一套系统化的NAT穿透方案,实现了一种具有NAT穿透能力的构件,可平滑地植入现有... 为了解决IPv4地址匮乏问题,网络中部署了大量的NAT设备,而NAT的部署破坏了Internet端到端的特性,并给不断发展的网络多媒体应用带来了障碍。针对该问题,提出一套系统化的NAT穿透方案,实现了一种具有NAT穿透能力的构件,可平滑地植入现有的流媒体产品中,并降低软件开发的复杂度,从而可很好地解决NAT部署带给流媒体的障碍。 展开更多
关键词 网络地址转换器(network ADDRESS sranslator NAT)穿透 音视频通讯 STUN
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Takotsubo syndrome:Advances in the understanding and management of an enigmatic stress cardiomyopathy 被引量:2
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作者 Hernán David Mejía-Rentería Iván J Núnez-Gil 《World Journal of Cardiology》 CAS 2016年第7期413-424,共12页
Takotsubo cardiomyopathy is a syndrome mimicking an acute myocardial infarction in absence of obstructive epicardial coronary artery disease to explain the degree of the wall motion abnormalities. Typically more commo... Takotsubo cardiomyopathy is a syndrome mimicking an acute myocardial infarction in absence of obstructive epicardial coronary artery disease to explain the degree of the wall motion abnormalities. Typically more common in the elderly women, this condition is usually triggered by unexpected emotional or physical stress situations, and is associated with electrocardiogram abnormalities and slight elevation of cardiac biomarkers. The pathophysiological mechanism is not clear yet, but it is believed that a high circulating concentration of catecholamines causes an acute dysfunction of the coronary microcirculation and metabolism of cardiomyocytes, leading to a transient myocardial stunning. Typically, it presents with acute left ventricular systolic dysfunction that in most cases is completely resolved at short term. Recurrences are rare and it is thought that the long-term prognosis is good. We present here a review of the clinical features, pathophysiology and management of this enigmatic condition. 展开更多
关键词 Takotsubo cardiomyopathy STRESS REVIEW Myocardial stunning Left ventricle systolic dysfunction
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SIP协议的NAT穿越研究 被引量:8
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作者 高扬 糜正琨 《重庆邮电学院学报(自然科学版)》 2006年第4期503-507,共5页
SIP协议是IETF定义的IP多媒体通信控制协议,也是下一代网络(NGN)的核心控制协议。SIP音视频通信应用的快速发展与IPv4地址资源不足的矛盾提出了NAT穿越问题。针对SIP信令和媒体流的NAT穿越问题,阐述了现有媒体流穿越的解决方案,介绍了基... SIP协议是IETF定义的IP多媒体通信控制协议,也是下一代网络(NGN)的核心控制协议。SIP音视频通信应用的快速发展与IPv4地址资源不足的矛盾提出了NAT穿越问题。针对SIP信令和媒体流的NAT穿越问题,阐述了现有媒体流穿越的解决方案,介绍了基于STUN协议的企业网NAT穿越实现。 展开更多
关键词 会话初始化协议 下一代网络 网络地址翻译 STUN NAT穿越
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NAT和防火墙穿越技术研究 被引量:3
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作者 韩可玉 王振涛 苏继斌 《软件导刊》 2014年第3期134-136,共3页
在研究分析常用的NAT和防火墙穿越技术优缺点的基础上,设计了"STUN+TURN"的STR NAT和防火墙穿越整体方案,同时对该方案涉及的相关问题进行了深入研究,形成了相得益彰、浑然一体、普适易用的NAT和防火墙穿越解决方案。
关键词 NAT和防火墙穿越 STUN TURN
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