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腘动脉弯曲特征在下肢缺血病变腔内治疗中的应用
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作者 刘小春 叶波 +3 位作者 郑国富 谢海亮 陈伟清 熊吉信 《江西医药》 CAS 2016年第8期736-737,745,共3页
目的评估动脉在膝关节不同功能状态下的弯曲特征,探讨动脉的弯曲特征在下肢缺血性病变中腔内治疗中的临床意义。方法选择2014年9月到2015年8月我院动脉硬化闭塞症16例(16条肢体)患者,采取膝关节屈曲和伸直位对动脉造影,明确... 目的评估动脉在膝关节不同功能状态下的弯曲特征,探讨动脉的弯曲特征在下肢缺血性病变中腔内治疗中的临床意义。方法选择2014年9月到2015年8月我院动脉硬化闭塞症16例(16条肢体)患者,采取膝关节屈曲和伸直位对动脉造影,明确动脉拐点所在位置;根据动脉拐点所在位置进行动脉支架治疗。结果 动脉具有多种弯曲形态,其中4例拐点位于P1段,10例位于P2段,2例位于P3段;支架末端位于P1段的10例,位于P2段的6例。16例患者动脉支架术后即刻通畅率达100%。结论 动脉的弯曲特征对动脉支架植入时的定位具有十分重要的临床指导意义。 展开更多
关键词 动脉 闭塞性动脉硬化 弯曲特征 腔内治疗
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小剂量测试技术和对比剂团注跟踪自动触发技术在肺动脉CTA的对比研究 被引量:6
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作者 翟红伟 李添 +2 位作者 吴守红 林圣美 杜瑞宾 《创伤与急诊电子杂志》 2015年第2期27-29,9,共4页
目的对比研究小剂量测试技术和对比剂团注跟踪自动触发技术在肺动脉CTA诊断的意义。方法随机选取本院行肺动脉CTA检查的患者70例,将患者分成两组(每组35例),组1用小剂量测试技术扫描方式,组2用对比剂团注跟踪技术自动触发扫描,所有数据... 目的对比研究小剂量测试技术和对比剂团注跟踪自动触发技术在肺动脉CTA诊断的意义。方法随机选取本院行肺动脉CTA检查的患者70例,将患者分成两组(每组35例),组1用小剂量测试技术扫描方式,组2用对比剂团注跟踪技术自动触发扫描,所有数据均在后处理工作站行多平面重组技术(multi planar reformatting,MPR)、最大密度投影(maximum intensity projection,MIP)和容积重现(volume rendering,VR)后处理,由两名高年资(主治职称以上)医生采用双盲法行主观评价,然后在工作站上测量肺动脉干、肺静脉和升主动脉CT值并应用统计学方法进行比较。结果两种扫描方式所获图像质量在主观评估方面无统计学意义(P>0.05)。两组图像的肺动脉干、肺静脉和升主动脉CT值差异有统计学意义(P<0.05),且小剂量测试扫描方法所用造影剂剂量更少。结论两种扫描方案(小剂量测试技术和对比剂团注跟踪自动触发技术)检查肺动脉所得图像中,主观影像质量评估无统计学差异,而客观影像质量评估(肺动脉干、肺静脉和升动脉CT值)有统计学意义(P<0.05),且小剂量测试扫描方式所用造影剂的剂量较少,故应用小剂量测试技术进行肺动脉CTA的检查具有重要的临床价值。 展开更多
关键词 动脉CTA 小剂量测试 对比剂团注跟踪技术
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0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis
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作者 LIU Shanfeng LU Xiaochen +1 位作者 TIAN Hao WU Huiqun 《中国医学影像技术》 CSCD 北大核心 2024年第8期1236-1241,共6页
Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Base... Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis. 展开更多
关键词 coronary stenosis HEMODYNAMICS coronary angiography tomography X-ray computed
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Ultrafast pulse wave velocity technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis patients with euthyroidism
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作者 JIANG Yanhui LIU Meiling +1 位作者 XIE Jingwen ZHANG Jianxing 《中国医学影像技术》 CSCD 北大核心 2024年第8期1179-1182,共4页
Objective To explore the value of ultrafast pulse wave velocity(UFPWV)technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis(HT)patients with euthyroidism.Methods Conventional ultrasoun... Objective To explore the value of ultrafast pulse wave velocity(UFPWV)technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis(HT)patients with euthyroidism.Methods Conventional ultrasound and UFPWV for carotid artery were prospectively performed in 91 HT patients with euthyroidism(HT group)and 81 healthy subjects(control group).Clinical data and ultrasonic parameters were compared between groups.Spearman correlation analysis was performed to observe the correlations of carotid pulse wave velocity in end of systole(PWV-ES)with clinical indexes and other ultrasonic parameters in HT group.Multiple stepwise linear regression analysis was used to screen the independent impact factors of increased carotid PWV-ES in HT group.Results Significant differences of thyroid peroxidase antibody(TPOAb),thyroglobulin antibody(TgAb),total cholesterol(TC),low density lipoprotein and neutrophil-lymphocyte ratio(NLR)were found between groups(all P<0.05).The carotid PWV-ES in HT group was significantly higher than that in control group(P<0.05),while no significant difference of carotid artery intima-media thickness(CIMT)nor carotid pulse wave velocity in beginning of systole(PWV-BS)was found between groups(both P>0.05).Carotid PWV-ES in HT group was positively correlated with patients'age,body mass index,TPOAb,TC,triglyceride,NLR and CIMT(r=0.217—0.707,all P<0.05).Patients'age,TPOAb and NLR were all independent impact factors of increased carotid PWV-ES in HT patients with euthyroidism(all P<0.05).Conclusion UFPWV technique could be used to evaluate changes of carotid artery elasticity in HT patients with euthyroidism,among which PWV-ES was relatively sensitive. 展开更多
关键词 Hashimoto disease carotid arteries ULTRASONOGRAPHY prospective studies
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冠状动脉CTA评估心肌桥形态特征、发生位置与冠状动脉粥样硬化的关系 被引量:6
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作者 杨扬 《中外医疗》 2016年第19期194-195,共2页
目的探讨冠状动脉CTA评估心肌桥形态特征、发生位置与冠状动脉粥样硬化的关系。方法方便抽取2013年4月—2015年11月该院收治的50例行冠状动脉CTA检查患者的图像资料,结合其心电图及心脏超声表现,并评估心肌桥与冠状动脉粥样硬化的关系... 目的探讨冠状动脉CTA评估心肌桥形态特征、发生位置与冠状动脉粥样硬化的关系。方法方便抽取2013年4月—2015年11月该院收治的50例行冠状动脉CTA检查患者的图像资料,结合其心电图及心脏超声表现,并评估心肌桥与冠状动脉粥样硬化的关系。结果肌桥的发生率为40.00%,以前降支最为多见,占45.00%。前降支存在心肌桥的患者,血管冠状动脉粥样硬化的发生率明显高于无心肌桥的患者,差异有统计学意义(P<0.05);心肌桥近端冠状动脉粥样硬化的发生率明显高于壁冠状动脉及其远端冠状动脉粥样硬化的发生率,差异有统计学意义(P<0.05)。结论心肌桥近端动脉极易导致冠状动脉粥样硬化,可作为评估冠状动脉粥样硬化性心脏病的危险因素之一。 展开更多
关键词 冠状动脉CTA 心肌桥形态特征 冠状动脉粥样硬化
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Mechanism of anti-arterial thrombosis of Dahuangzhecong Fang screened by Ti-Al intermetallic compound porous material 被引量:2
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作者 万玲 王战义 +6 位作者 魏星 李佶阳 钟广伟 段晓鹏 贺福元 江垚 王东生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3156-3160,共5页
The mechanism of antithrombotic of Dahuangzhechong Fang separated and purified by Ti-Al intermetallic compound porous material (TAICPM) was researched. Dahuangzhechong Fang, which was isolated and screened by TAICPM, ... The mechanism of antithrombotic of Dahuangzhechong Fang separated and purified by Ti-Al intermetallic compound porous material (TAICPM) was researched. Dahuangzhechong Fang, which was isolated and screened by TAICPM, was used to oral rats. At the end of study, their blood and thrombus were collected. The results show that TAICPM with the pore size of 1-5 μm can screen Dahuangzhechong Fang well. Dahuangzhechong Fang can increase 6-keto-PGF1α, lower content of TXD2 and platelet. Dahuangzhechong Fang has good effect to resist arterial thrombosis. 展开更多
关键词 Ti-Al intermetallic compound porous materials Dahuangzhecong Fang arterial thrombosis isolated Chinese medicine
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Three-dimensional Imaging of Multi-slice Spiral CT in Bronchial Artery Correlative Study on Blood Supply of Central Lung Cancer and Its Clinical Significance 被引量:4
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作者 李智勇 杨冬 +2 位作者 伍建林 黎庶 董天 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期40-42,67,共4页
Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention t... Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention therapy. Methods: Eighteen patients with central lungcancer underwent MSCT with real time helical thin-slice CT scanning. Three-dimensional bronchialartery reconstruction was done at the console work-station. The space anatomical characters ofbronchial artery were observed through different rotations. Results: For 6 cases, thethree-dimensional images of bronchial artery (33.33%) could exactly show the origins, the routes(lung inner segment and mediatism segment) and the diameters of bronchial arteries. Vision rate ofbronchial arteries was the highest in pulmonary artery stricture and truncation groups, and thevessels' diameter became larger apparently. These characters demonstrated blood supply of this kindof central lung cancer come from bronchial artery. Volume rendering images were the best ones amongthree-dimensional images. Conclusion: Three-dimensional imaging with MSCT in bronchial artery canreveal the anatomical characters of bronchial artery and provide theoretical evidence on bloodsupply and intervention therapy of central lung cancer. 展开更多
关键词 bronchial artery multi-slice spiral CT three-dimensional reconstruction ANGIOGRAPHY
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Pathological Study of Excised Specimens from Resectable Large Hepatocellular Carcinoma after Transcatheter Arterial Chemoembolization 被引量:2
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作者 周伟平 周建平 +4 位作者 丛文铭 傅思源 姚晓平 陈汉 吴孟超 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第1期11-14,64,共5页
Objective: To investigate pathological changes in surgically excised specimens from resectable large hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE ) and their ... Objective: To investigate pathological changes in surgically excised specimens from resectable large hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE ) and their signi?cance. Methods: From January 2002 to January 2003, 83 patients with resectable large HCC were randomized into two groups: group A, 36 patients who underwent preoperative TACE, and group B, 47 patients who underwent one-stage operation without TACE. Hepatectomy was performed in 31 patients of group A (two-stage operation group) and 47 patients of group B (one-stage operation group). The remaining 5 patients in group A were not operable. The diagnosis of HCC was pathologically con?rmed in all 78 patients after hepatectomy. Pathological changes of the excised specimens between the two groups were compared, including main tumors, capsular containment, daughter nodules, tumor thrombi and liver cirrhosis. Results: There were no signi?cant di?erences in the incidence of daughter nodules , portal vein tumor thrombi (PVTT) and extrahepatic metastasis between the two groups, but the area of main tumor necrosis was more extensive and the rate of encapsulation was higher in two-stage operation group than those in one-stage operation group. No signi?cant shrinkage in the average tumor size was seen in two- stage operation group, where daughter nodules and PVTT necrosis were less, and liver cirrhosis was more serious. Conclusion: Preoperative TACE for resectable large HCC should be used on the basis of strict selection because it does not provide complete tumor necrosis and may result in delayed surgery in some cases. 展开更多
关键词 hepatocellular carcinoma CHEMOEMBOLIZATION HEPATECTOMY PATHOLOGY
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Primary Mechanisms for Novel Compound Pivanampeta Against Atherosclerosis in Rat and Rabbit Model of Atherosclerosis 被引量:1
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作者 山丽梅 张锦超 +1 位作者 赵艳玲 汪海 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期68-75,共8页
Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the mod... Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the model and the pivanampeta-treated groups. The rats or rabbitsin the model group and the pivanampeta-treated group were fed with hypercholesterol diet. Thecarotids of rabbits were cut into pieces and stained with HE. The rat or rabbit serum levels of TC,LDL-CHO, HDL-CHO, IL-8, ET-1, PGI_2, TXA_2, and NO were assayed. The expressions of MCP-1 and IL-8mRNA on rabbit carotid were determined by semi-quantitative RT-PCR. Results Pivanampeta exerted aninhibitory effect on TXA_2 formation without PGI_2 production in the early and later stages ofatherosclerosis. The significantly increased release of NO and the decreased release of IL-8 in theanimals in pivanampeta-treated group were both detected in the rat atherosclerosis model. In therabbit atherosclerosis model the expressions of IL-8 and MCP-1 mRNA in pivanampeta-treated groupwere decreased significantly. However, the treatment with pivanampeta had no effect on the levels ofplasma cholesterol, MDA and SOD. Conclusion The increase of serum NO contents and the decrease ofplasma TXA_2 level, as well as its inhibition of expression of IL-8 and MCP-1 are probably involvedin the mechanisms underlying the anti-atherosclerotic effects of pivanampeta. 展开更多
关键词 ATHEROSCLEROSIS nitric oxide PGI_2 TXA_2
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DSA Diagnosis of Carotid Body Tumor 被引量:1
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作者 戚跃勇 徐健 +2 位作者 邹利光 周政 谭颖徽 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第2期114-116,127,128,共5页
Objective: To make a further understanding of the DSA features of the carotid body tumor (CBT) and to explore the clinical value of DSA diagnosis and interventional treatment for CBT. Methods: Twelve cases of CBT with... Objective: To make a further understanding of the DSA features of the carotid body tumor (CBT) and to explore the clinical value of DSA diagnosis and interventional treatment for CBT. Methods: Twelve cases of CBT with DSA data were analyzed retrospectively. The DSA appearances in all of the patients were observed dynamically in a double blind manner by two experienced radiologists together and a consensus interpretation formed. Results: DSA could establish definitive diagnosis in all cases. The DSA features of the CBT were: the increase of bifurcation angles of internal and external carotid arteries in all cases; the CBT supplied by external carotid arteries in most cases and the significant increase of tumor vessels in bifurcation; invasion of internal or external carotid arteries in 6 cases. The tumor staining disappeared mostly after the supplying arteris were embolized in 2 cases, and the bleeding during the operation reduced significantly. Conclusion: The DSA is useful in the diagnosis of the CBT and for therapeutic planning. The pre-operation embolization of the CBT contributes to reduce the bleeding during operation. 展开更多
关键词 carotid body tumor DSA EMBOLIZATION THERAPEUTIC
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The Preliminary Study of Certain Pharmacological Effects of Xi Xin Oil 被引量:2
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作者 胡月娟 徐军 纪绿屏 《Journal of Chinese Pharmaceutical Sciences》 CAS 1993年第2期156-158,共3页
细辛油能松弛兔离体主动脉条,使去甲肾上腺素所致主动脉收缩的量效曲线右移并效能降低;使离体兔耳灌流量减少;能延长小鼠常压耐缺氧时间;用其1/2 LD_(50)之剂量腹腔注射给药3天,可致小鼠骨髓微核形成增加。
关键词 Xi Xin Oil Aorta strip Anoxia tolerance Micronucleus test
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Sustained Contraction of Isolated Rabbit Thoracic Aortic Rings in Endothelial-dependent Manner Induced by βγ-CAT 被引量:3
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作者 刘树柏 何英英 +1 位作者 钱金桥 张云 《Zoological Research》 CAS CSCD 北大核心 2008年第5期493-502,共10页
In vertebrates, non-lens βγ-crystallins are widely expressed in various tissues and their functions are not well known. The molecular mechanisms of trefoil factors (TFFs), which involved in mucosal healing and tum... In vertebrates, non-lens βγ-crystallins are widely expressed in various tissues and their functions are not well known. The molecular mechanisms of trefoil factors (TFFs), which involved in mucosal healing and tumorigenesis, have remained elusive. βγ-CAT is a novel multifunctional protein complex of non-lens βγ-crystallin and trefoil factor from frog skin secretions. Here we report that βγ-CAT could induce sustained contraction of isolated rabbit aortic rings in dosage (2-35nmol/L) and endothelium dependent manners (P〈0.01 ). In addition, in situ immunofluorescence indicated that positive TNF-α signals were mainly detected at the endothelial cell layer of βγ-CAT (25nmol/L) treated rings. Furthermore, βγ-CAT induced primary cultured rabbit thoracic aortic endothelial cells (RAECs) rapidly to release TNF-α. After βγ-CAT (25nmol/L) treated for 10 and 30min, the levels of the endothelial cells released TNF-ct were 34.17±5.10 pg/mL and 98.01±4.67 pg/mL (P〈0.01), respectively. In conclusion, βγ-CAT could induce sustained contraction of isolated aortic rings, and the contractile effect might be partially explained by the release of TNF-α. These findings will give new insight into understanding the functions and physiological roles of non-lens βγ-crystallins and trefoil factors. 展开更多
关键词 Tumor necrosis factor-a Trefoil factor Non-lens βγ-crystallin Endothelium-dependent aorta vasoconstriction βγ-CAT
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Studies on Mitomycin C Dextran-microspheres 被引量:1
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作者 魏树礼 孙贻春 +4 位作者 张敬石 谭惟薇 谢敬霞 李选 朱建纲 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第1期33-40,共8页
In this paper,the preparation and properties of mitomycin C dextran-microspheres(MMC-DMS)were reported.The characteristics of pharmacokinetics and embolization effects of MMC-DMS in vivo were studied in dogs.The avera... In this paper,the preparation and properties of mitomycin C dextran-microspheres(MMC-DMS)were reported.The characteristics of pharmacokinetics and embolization effects of MMC-DMS in vivo were studied in dogs.The average diameter of the microspheres was 75±19μm and the content was 5% of MMC.In in vitro experiment, the release rate of drug demonstrated that the microspheres had sustained-release properties. The microspheres and conventional MMC were infused into the hepatic artery of dogs through a catheter for embolization,respectively.The plasma concentration of MMC was de- termined by HPLC.Results showed that the peak concentration of conventional MMC was 2.6 times as much as MMC-DMS.Angiograms revealed that peripheral blood vessels de- creased obviously in liver.The histopathologic examination showed that the microspheres lodged in the hepatic artery and displayed nodular necrosis in the embolized segment.The MMC-DMS were used in clinical trial in 100 patients with hepatic cancer.The tumor reduc- tion and improvement of symptoms in patients were observed after hepatic arterial embolization.The survival duration was prolonged.Results showed that the MMC-DMS is a promising embolic agent for treatment of hepatic cancer.It could aid in the use of intensive chemotherapy with minimum systemic side effect. 展开更多
关键词 Mitomycin C Mitomycin C dextran-microspheres Hepatic arterial embolization Hepatic cancer
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Preoperative Localization of Insulinoma by Intra-arterial Spiral CT 被引量:1
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作者 李立 吴沛宏 +2 位作者 谢传淼 林浩皋 陈林 《The Chinese-German Journal of Clinical Oncology》 CAS 2003年第1期49-52,62,共5页
Objective To evaluate the value of intra-arterial dynamic spiral CT on preoperative localization of insulinoma. Methods Two patients with insulinoma proved by operative pathology were preoperatively localized by int... Objective To evaluate the value of intra-arterial dynamic spiral CT on preoperative localization of insulinoma. Methods Two patients with insulinoma proved by operative pathology were preoperatively localized by intra-arterial dynamic spiral CT. Results In intra-arterial spiral CT, two small insulinomas (1.5–2.0 cm in diameter) demonstrated as a significantly high dense nodule 20 s later after initiation of injection of contrast medium. The course of high density lasted nearly 4 min. Conclusion Intra-arterial dynamic spiral CT could clearly detect small insulinoma, and might be one of most effective preoperative localization methods for small insulinoma. Key words insulinoma - anteriography - CT 展开更多
关键词 INSULINOMA anteriography CT
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Effect of electropulsing on dislocation mobility of titanium sheet 被引量:5
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作者 宋辉 王忠金 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1599-1605,共7页
To investigate the effect of the electropulsing on dislocation mobility,specimens cut from the cold-rolled titanium sheet were treated by high density electropulsing with the maximum current density of 7.22,7.64,7.96 ... To investigate the effect of the electropulsing on dislocation mobility,specimens cut from the cold-rolled titanium sheet were treated by high density electropulsing with the maximum current density of 7.22,7.64,7.96 kA/mm 2 ,pulse period 110μs.The internal friction and elastic modulus were measured by a dynamic mechanical analyzer(DMA).When strain amplitude lowers a certain critical one,the damping of the electropulsed titanium sheet is lower than that of the cold-rolled one.When the strain amplitude exceeds the critical one,the damping of the electropulsed titanium sheet is extraordinarily higher than that of the cold-rolled or conventional annealed one.Furthermore,it is found that the damping peak of the electropulsed titanium sheet shifts to lower temperature compared with the conventional annealed one.It is demonstrated that the electropulsing treatment can decrease dislocation tangles and enhance dislocation mobility. 展开更多
关键词 titanium alloys dislocation mobility DAMPING ELECTROPULSING
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Pulse Quick Charger of Electric Vehicle 被引量:3
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作者 张承宁 吴兵峰 +1 位作者 孙逢春 张旺 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期240-245,共6页
In order to improve the charging efficiency of lead acid battery, shorten the charging time and avoid the battery polarization, a new charging method was put forward. Based on the analyzed results of charging charact... In order to improve the charging efficiency of lead acid battery, shorten the charging time and avoid the battery polarization, a new charging method was put forward. Based on the analyzed results of charging characteristic of lead acid battery, a pulse quick charger is designed to adjust the charging current pulse’s amplitude and pulse width automatically stage by stage according to the measured battery voltage and feedback current. Compared with other kinds of quick chargers, it has such characteristics as shorter charging time, higher charging efficiency and lower temperature increasing during the charging process. As a result, the battery polarization is reduced efficiently. 展开更多
关键词 pulse quick charger lead acid battery electric vehicle
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ROBUST ADAPTIVE CONTROL SCHEME FOR IMPROVING LOW-SPEED PROFILE TRACKING PERFORMANCE OF HYBRID STEPPING MOTOR SERVO DRIVE 被引量:3
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作者 陈卫东 容启亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期8-16,共9页
A robust adaptive control approach is presented to improve the performance of the control scheme proposed in the authors' previous work, aiming at producing a low ripple hybrid stepping motor servo drive for precisio... A robust adaptive control approach is presented to improve the performance of the control scheme proposed in the authors' previous work, aiming at producing a low ripple hybrid stepping motor servo drive for precision profile tracking at a low speed. In order to construct a completely integrated control design philosophy to reduce torque ripple and at the same time to enhance tracking performance, the properties of nonlinear uncertainties in the system dynamics are uncovered, and then incorporated into the design of the controller. The system uncertainties concerned with ripple dynamics and other external disturbances are composed of two categories. The first category of uncertainties with linear parameterization arising from the detention effect is dealt with by the wellknown adaptive control method. A robust adaptive method is used to deal with the second category of uncertainties resulting from the non-sinusoidal flux distribution. The μ-modification scheme is used to cease parameter adaptation by the robust adaptive control law, thus ensuring that the trajectory tracking error asymptotically converges to a pre-specified boundary. Experiments are performed with a typical hybrid stepping motor to test its profile tracking accuracy. Results confirm the proposed control scheme. 展开更多
关键词 robust adaptive control tracking control stepping motor torque ripple
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Studies on Adriamycin Magnetic Gelatin Microspheres
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作者 吴传斌 魏树礼 +5 位作者 卢炜 何素梅 高文伟 王田力 李选 谢敬霞 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第1期1-7,共7页
The preparation and properties of adriamycin magnetic gelatin microspheres(Adr- MG-ms)were reported.The synthesis of magnetic iron oxide ultrafine particle and embolization effects of magnetic gelatin microspheres(MG-... The preparation and properties of adriamycin magnetic gelatin microspheres(Adr- MG-ms)were reported.The synthesis of magnetic iron oxide ultrafine particle and embolization effects of magnetic gelatin microspheres(MG-ms)in dog were studied.Adr- MG-ms consist of 2%(w/w)of adriamycin(Adr)as the core,and 68% of gelatin and 30% of magnetite as the shell with a mean particle size of 22 μm. In vitro experiment,the release rate of drug demonstrated that the microspheres have sustained-release properties.The average diameter of magnetic iron oxide was approximately l0 nm. Transcatheter embolization with MG-ms and  ̄(99m)Tc-labelled MG-ms was performed under external magenet control in dog liver,respectively.Gamma photography and angiogram revealed that MG-ms level was almost equal both in left and right hepatic arteries without magnet,while with magnet(1200 Gs),MG-ms level in left hepatic artery(target site)was about 2.25 fold higher than in right hepatic artery,and few MG-ms in thyroid gland,brain and heart was observed.Results showed that the MG-ms is a promising embolic agent for treatment of hepatic cancer under external magnet control. 展开更多
关键词 ADRIAMYCIN Adriamycin magnetic gelatin microspheres Magnetic gelatin microspheres Hepatic arterial embolization
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Effects of basic fibroblast growth factor on ischemic gut and liver injuries
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作者 付小兵 盛志勇 +6 位作者 王亚平 叶一秀 孙同柱 马诺山 常国友 许明火 周宝桐 《World Journal of Gastroenterology》 SCIE CAS CSCD 1996年第3期139-140,172,共3页
AIMS To explore the possible effects of basic fibrob- last growth factor (bFGF) on ischemic gut and liver in- juries after trauma. METHODS Animal model of super mesenteric artery (SMA) occlusion was used in this study... AIMS To explore the possible effects of basic fibrob- last growth factor (bFGF) on ischemic gut and liver in- juries after trauma. METHODS Animal model of super mesenteric artery (SMA) occlusion was used in this study. Seventy-two Wistar rats were divided into three groups of 24 rats each. Each animal in group 1 (bFGF treated) was in- jected with 4 μg of bFGF in 0.15 ml of normal saline solution containing 0.1%(w/v) heparin through the jugular vein at the onset of reperfusion. Animals in group 2 (saline treated) received the same vehicle, but without bFGF. Group 3 (sham-operated) ani- mals were treated with the same operations,but without SMA occlusion. Liver function parameters, serum TNFα,bacterial examination and pathological study were used to evaluate the results. RESULTS In group 1,the amounts of ALT and AST and serum TNFα were reduced significantly at 6,24 and 48 hours as compared with group 2. Bacterial ex- amination showed that the bacterial translocation from gut to liver,spleen and MLN in group 1 was much lower than that in group 2. The pathological results support the concept of significant protecting effects of bFGF. CONCLUSIONS Venous administration of bFGF may help reduce gut and liver injuries after ischemia and reperfusion. Its mechanism of action may involve the mitogenic and non-mitogenic effects of bFGF. 展开更多
关键词 INTESTINES LIVER fibroblast growth factor mesenteric arteries
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Role of Early Arterial Phase Multislice Helical CT Angiography in Evaluation of Hepatocellular Carcinoma
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作者 唐秉航 何亚奇 +3 位作者 李良才 黄德成 吴任国 余元龙 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第3期146-150,188,共6页
Objective: To investigate the clinical application of early arterial phase multislice CT angiog raphy (MSCTA) of hepatic vessels in evaluation of middle or advanced stage hepatocellular carcinoma. Methods: Trigger Bol... Objective: To investigate the clinical application of early arterial phase multislice CT angiog raphy (MSCTA) of hepatic vessels in evaluation of middle or advanced stage hepatocellular carcinoma. Methods: Trigger Bolus program was used to carry out MSCTA in early and late arterial phases and portal vein phase with single breath holding. Hepatic vessels were reconstructed from the original images of early arterial phase by post processing. The blood supply of tumor and normal liver tissue and the appearances of venous thrombosis and arteriovenous shunts were analyzed. Results: The MSCTA with early arterial phase could perfectly display the origin, shape and amount of feeding vessels to normal liver tissue and tumor in middle or advanced stage hepatocellular carcinoma. It had the ability of displaying the arteriovenous shunts better than that in conventional dual phased liver scanning. Conclusion: MSCTA of hepatic vessels with early arterial phase acquisition using multislice helical CT in middle or advance stage hepatocellular carcinoma has favorable and promising application. It can be used as an imaging method for comprehensive assessment of the hepatocellular carcinoma before treatment. 展开更多
关键词 carcinoma hepatocellular blood supply ANGIOGRAPHY tomography X-ray computed
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