Portal hypertension is responsible for the bulk of the morbidity and mortality in patients with cirrhosis.Drug therapy to reduce portal pressure involves targeting two vascular beds.The first approach is to reduce int...Portal hypertension is responsible for the bulk of the morbidity and mortality in patients with cirrhosis.Drug therapy to reduce portal pressure involves targeting two vascular beds.The first approach is to reduce intra hepatic vascular tone induced by the activity of powerful vasocontrictors such as angiotensin Ⅱ,endothelin-1 and the sympathetic system and mediated via contraction of perisinusoidal myofibroblasts and pervascular smooth muscle cells.The second approach is to reduce mesenteric and portal blood flow.Non-selective b-blockers are widely used and have been shown to prolong patient survival and reduce oesophageal variceal bleeding in advanced cirrhosis.However many patients are unable to tolerate these drugs and they are ineffective in a significant proportion of patients.Unfortunately there are no other drug therapies that have proven efficacy in the treatment of portal hypertension and prevention of variceal bleeding.This review briefly outlines current therapeutic approaches to themanagement of portal hypertension,and the evidence supporting the role of the renin angiotensin system(RAS) and the use of RAS blockers in this condition.It will also outline recent advances in RAS research that could lead to the development of new treatments focusing in particular on the recently discovered "alternate axis" of the RAS.展开更多
Bled air from the high pressure compressor takes up 3%—5% in the air system.However,there are not many studies on the compressor performance after bleeding.By analyzing the low-speed single-stage compressors,six blee...Bled air from the high pressure compressor takes up 3%—5% in the air system.However,there are not many studies on the compressor performance after bleeding.By analyzing the low-speed single-stage compressors,six bleeding structures are presented according to their influence mechanism on the compressor performance,and five kinds of bleeding rate are applied to one of the structures.A numerical simulation is performed to study the influence of bleeding rates and structures on the compressor performance.The results show that for the stators with the large flow separation in the corner,bleeding a small amount of air from the end-wall region can improve the total pressure increase and the stability margin.Moreover there is an optimum value of the bleeding rate in the stator casing.展开更多
In clinical practice,examination of the hemorrhagic spot (HS) remains difficult.In this paper,we describe a remote controlled capsule (RCC) micro-system with an automated,color-based sensor to identify and localize th...In clinical practice,examination of the hemorrhagic spot (HS) remains difficult.In this paper,we describe a remote controlled capsule (RCC) micro-system with an automated,color-based sensor to identify and localize the HS of the gastrointestinal (GI) tract.In vitro testing of the detecting sensor demonstrated that it was capable of discriminating mimetic intestinal fluid (MIF) with and without the hemoglobin (Hb) when the concentration of Hb in MIF was above 0.05 g/ml.Therefore,this RCC system is able to detect the relatively accurate location of the HS in the GI tract.展开更多
目的探讨MELD(model for end-stage liver disease)、GBS(glasgow-blatchford score)、AIMS65评分系统在肝硬化食管胃底静脉曲张破裂出血(esophageal and gastric variceal bleeding,EGVB)患者风险评估中的临床应用价值。方法对天津医...目的探讨MELD(model for end-stage liver disease)、GBS(glasgow-blatchford score)、AIMS65评分系统在肝硬化食管胃底静脉曲张破裂出血(esophageal and gastric variceal bleeding,EGVB)患者风险评估中的临床应用价值。方法对天津医科大学总医院消化内科2015年1月1日至2018年3月1日入院的182例肝硬化EGVB患者进行回顾分析,依据MELD、GBS、AIMS65评分系统标准针对每例患者进行评分,评估各评分系统正确将肝硬化EGVB归为"高风险患者"的能力,并绘制受试者工作特征曲线(receiver-operating characteristic curve,ROC),采用曲线下面积(area under curve,AUC)评估各评分系统针对不同临床结局(输血、再出血、住院死亡)的预测能力,AUC>0.7认为有较高准确性。结果临床结局包括输血113例(62.1%)、再出血31例(17.0%)、死亡11例(6.0%)。MELD评分得分为7~25分,其中得分<9分4例(2.2%);GBS评分得分为3~16分;AIMS65评分得分为0~3分,其中得分0~1分139例(76.4%,0分68例、1分71例)。MELD、GBS、AIMS65评分系统预测输血的AUC分别为0.514(95%CI:0.439~0.589)、0.681(95%CI:0.608~0.748)、0.669(95%CI:0.596~0.737);预测再出血的AUC分别为0.525(95%CI:0.449~0.599)、0.528(95%CI:0.453~0.602)、0.580(95%CI:0.505~0.652);预测住院死亡的AUC分别为0.642(95%CI:0.567~0.711)、0.581(95%CI:0.505~0.653)、0.786(95%CI:0.719~0.843),AIMS65优于MELD(P=0.0836)和GBS(P=0.0470)。结论GBS能正确将肝硬化EGVB患者归类为"高风险人群",优于AIMS65和MELD评分系统。对于肝硬化EGVB患者,3种评分系统对输血和再出血的预测价值均不高,AIMS65对住院死亡有较高的预测价值。展开更多
基金Supported by Grant from the National Health and Medical Research Council of Australia
文摘Portal hypertension is responsible for the bulk of the morbidity and mortality in patients with cirrhosis.Drug therapy to reduce portal pressure involves targeting two vascular beds.The first approach is to reduce intra hepatic vascular tone induced by the activity of powerful vasocontrictors such as angiotensin Ⅱ,endothelin-1 and the sympathetic system and mediated via contraction of perisinusoidal myofibroblasts and pervascular smooth muscle cells.The second approach is to reduce mesenteric and portal blood flow.Non-selective b-blockers are widely used and have been shown to prolong patient survival and reduce oesophageal variceal bleeding in advanced cirrhosis.However many patients are unable to tolerate these drugs and they are ineffective in a significant proportion of patients.Unfortunately there are no other drug therapies that have proven efficacy in the treatment of portal hypertension and prevention of variceal bleeding.This review briefly outlines current therapeutic approaches to themanagement of portal hypertension,and the evidence supporting the role of the renin angiotensin system(RAS) and the use of RAS blockers in this condition.It will also outline recent advances in RAS research that could lead to the development of new treatments focusing in particular on the recently discovered "alternate axis" of the RAS.
基金Supported by the National Natural Science Foundation of China(60934001)~~
文摘Bled air from the high pressure compressor takes up 3%—5% in the air system.However,there are not many studies on the compressor performance after bleeding.By analyzing the low-speed single-stage compressors,six bleeding structures are presented according to their influence mechanism on the compressor performance,and five kinds of bleeding rate are applied to one of the structures.A numerical simulation is performed to study the influence of bleeding rates and structures on the compressor performance.The results show that for the stators with the large flow separation in the corner,bleeding a small amount of air from the end-wall region can improve the total pressure increase and the stability margin.Moreover there is an optimum value of the bleeding rate in the stator casing.
基金Project supported by the National Natural Science Foundation of China (Nos. 30700160 and 30970883)the Postdoctoral Science Foundation of China (Nos. 20070420718 and 200801225)+1 种基金Chongqing University Postgraduates’ Science and Innovation Fund (No. 2008 01A1B0250284)the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20070611045), China
文摘In clinical practice,examination of the hemorrhagic spot (HS) remains difficult.In this paper,we describe a remote controlled capsule (RCC) micro-system with an automated,color-based sensor to identify and localize the HS of the gastrointestinal (GI) tract.In vitro testing of the detecting sensor demonstrated that it was capable of discriminating mimetic intestinal fluid (MIF) with and without the hemoglobin (Hb) when the concentration of Hb in MIF was above 0.05 g/ml.Therefore,this RCC system is able to detect the relatively accurate location of the HS in the GI tract.
文摘目的探讨MELD(model for end-stage liver disease)、GBS(glasgow-blatchford score)、AIMS65评分系统在肝硬化食管胃底静脉曲张破裂出血(esophageal and gastric variceal bleeding,EGVB)患者风险评估中的临床应用价值。方法对天津医科大学总医院消化内科2015年1月1日至2018年3月1日入院的182例肝硬化EGVB患者进行回顾分析,依据MELD、GBS、AIMS65评分系统标准针对每例患者进行评分,评估各评分系统正确将肝硬化EGVB归为"高风险患者"的能力,并绘制受试者工作特征曲线(receiver-operating characteristic curve,ROC),采用曲线下面积(area under curve,AUC)评估各评分系统针对不同临床结局(输血、再出血、住院死亡)的预测能力,AUC>0.7认为有较高准确性。结果临床结局包括输血113例(62.1%)、再出血31例(17.0%)、死亡11例(6.0%)。MELD评分得分为7~25分,其中得分<9分4例(2.2%);GBS评分得分为3~16分;AIMS65评分得分为0~3分,其中得分0~1分139例(76.4%,0分68例、1分71例)。MELD、GBS、AIMS65评分系统预测输血的AUC分别为0.514(95%CI:0.439~0.589)、0.681(95%CI:0.608~0.748)、0.669(95%CI:0.596~0.737);预测再出血的AUC分别为0.525(95%CI:0.449~0.599)、0.528(95%CI:0.453~0.602)、0.580(95%CI:0.505~0.652);预测住院死亡的AUC分别为0.642(95%CI:0.567~0.711)、0.581(95%CI:0.505~0.653)、0.786(95%CI:0.719~0.843),AIMS65优于MELD(P=0.0836)和GBS(P=0.0470)。结论GBS能正确将肝硬化EGVB患者归类为"高风险人群",优于AIMS65和MELD评分系统。对于肝硬化EGVB患者,3种评分系统对输血和再出血的预测价值均不高,AIMS65对住院死亡有较高的预测价值。
