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Objective To investigate the features of hepatic angiomyolipoma(AML) on contrast enhanced ultrasound (CEUS). Methods Ten pathologically proved AML lesions in 9 patients were evaluated by using baseline ultrasound and CEUS. CEUS was performed with contrast pulse sequencing technique and the contrast agent of SonoVue. Results On baseline ultrasound, 7 lesions exhibited mixed echoic,which was obvious hyperechoic combined with partly of hypoechoie; 3 lesions exhitited obvious hypereehoic. On color Doppler flow imaging artery signals were detected in all lesions. And the lesions had plenty or slightly plenty of artery supply,with resistive index about 0.53 4±0.10 (0.48~0.62). On CEUS, in the arterial phase, 9 lesions exhibited hyper-enhanced. In the portal phase, 5 lesions exhibited iso-enhancement,1 lesion was slightly hyper-enhancement and 3 lesions was hypo-enhancement. In the late phase 6 lesions were iso-enhancement and 3 lesions were hypo-enhancement. One lesion was all hypo-enhancement in all three phases. Conclusions There are some characteristic manifestations of hepatic AML in CEUS, which are helpful for the diagnosis of hepatic AML in a way,but we still need more experiences. 相似文献
223.
Objective To investigate the features of hepatic angiomyolipoma(AML) on contrast enhanced ultrasound (CEUS). Methods Ten pathologically proved AML lesions in 9 patients were evaluated by using baseline ultrasound and CEUS. CEUS was performed with contrast pulse sequencing technique and the contrast agent of SonoVue. Results On baseline ultrasound, 7 lesions exhibited mixed echoic,which was obvious hyperechoic combined with partly of hypoechoie; 3 lesions exhitited obvious hypereehoic. On color Doppler flow imaging artery signals were detected in all lesions. And the lesions had plenty or slightly plenty of artery supply,with resistive index about 0.53 4±0.10 (0.48~0.62). On CEUS, in the arterial phase, 9 lesions exhibited hyper-enhanced. In the portal phase, 5 lesions exhibited iso-enhancement,1 lesion was slightly hyper-enhancement and 3 lesions was hypo-enhancement. In the late phase 6 lesions were iso-enhancement and 3 lesions were hypo-enhancement. One lesion was all hypo-enhancement in all three phases. Conclusions There are some characteristic manifestations of hepatic AML in CEUS, which are helpful for the diagnosis of hepatic AML in a way,but we still need more experiences. 相似文献
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目的:探讨下肢静脉功能不全患者小腿交通静脉超声改变与临床表现的关系。方法:用彩色多普勒超声检查下肢静脉功能不全患者45例50条下肢的小腿交通静脉的数目、部位、内径及血流速度,并分别与患者的临床表现分级进行相关性分析。结果:彩色多普勒超声检出交通静脉扩张的“数目、内径及血流速度”与患者临床表现分级呈正相关,相关系数分别为0.48、0.55、0.51,P值均<0.05。结论:随小腿扩张交通静脉数目增加、内径增宽、血流速度升高,临床表现加重。 相似文献
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目的 探讨超声造影参数成像评估肝细胞性肝癌(hepatocellular carcinoma,HCC)和肝局灶性结节增生(focal nodular hyperplasia,FNH)的临床应用价值.方法 随机抽取接受超声造影检查并经临床或病理确诊的HCC和FNH各30例,利用SonoLiver CAP定量软件对其进行定量分析;以病灶与周围肝实质的增强水平差值为参数进行动态血管模型(dynamic vascular patterns,DVP)参数成像,比较HCC和FNH各参数及DVP有无差异.结果 HCC和FNH的上升时间、达峰时间、平均渡越时间依次分别为(16.7±11.1)s和(21.9±9.0)s(P=0.052)、(29.9±14.1)s和(33.2±11.1)s(P=0.322)、(115.0±90.9)s和(271.5±147.6)s(P=0.000),灌注指数分别为90.4±102.5和42.6±37.1(P=0.022).DVP曲线和DVP分布图可分为三种类型:消退型、未消退型以及负向型,在DVP曲线中,HCC和FNH这三种类型分别占76.7%(23/30)和43.3%(13/30)、20.0%(6/30)和53.3%(16/30)、3.3%(1/30)和3.3%(1/30)(P=0.023);在DVP分布图中HCC和FNH这三种类型分别占66.7%(20/30)和33.3%(10/30)、30.0%(9/30)和60.0%(18/30)、3.3%(1/30)和6.7%(2/30)(P=0.033).DVP分布图中30.0%(9/30)FNH表现出特异的轮辐状填充.结论 超声造影参数成像上HCC的平均渡越时间短于FNH,灌注指数高于FNH;DVP可以直观显示增强水平快速或细微的变化.Abstract: Objective To investigate the usefulness of parametric imaging of contrast-enhanced ultrasound(CEUS) in evaluating hepatocellular carcinoma ( HCC) and focal nodular hyperplasia(FNH). Methods Thirty clinically or pathologically proven HCCs and 30 pathologically proven FNHs that had undergone CEUS were randomly included. SonoLiver CAP software were used to quantitatively anlalyze the CEUS and reconstruct DVP parametric images. Results The rise time, time to peak and mean transit time in HCC and FNH were (16. 7 ± 11. 1)s and (21.9±9. 0)s (P = 0. 052) ,(29. 9 ± 14. l)s and (33. 2 ±11.1)s ( P =0. 322), (115. 0±90. 9)s and (271. 5 ± 147. 6)s ( P = 0. 000),respectively. The perfusion index was 90. 4 + 102. 5 in HCC and 42. 6 + 37. 1 in FNH( P = 0. 022). DVP curve and DVP parametric image could both be divided into three types: washout, non-washout and cystic type. In DVP curve, the percentages of which were 76. 7% (23/30),20. 0% (6/30),3. 3% (1/30) in HCC, and 43. 3% (13/30) , 53. 3% (16/30) , 3. 3%(l/30) in FNH,respectively ( P = 0. 023). In DVP parametric image, the percentages of which were 66. 7%(20/30) ,30. 0%(9/30) ,3. 3%(l/30) in HCC,and 33. 3%(10/30) ,60. 0%(18/30) ,6. 7%(2/30) in FNH,respectively ( P = 0. 033). 30. 0% (9/30) of FNH had a clear spoke-wheel pattern in DVP parametric image. Conclusions In parametric imaging of CEUS, the mean transit time of HCC was shorter than that of FNH,and the perfusion index of HCC was higher than that of FNH. The DVP parametric image can display the rapid change and detail of the enhancement clearly. 相似文献
227.
目的 观察雌激素对海水淹溺型肺损伤大鼠肺组织水通道蛋白表达的影响.方法 90只健康雄性SD大鼠随机分为三组,即对照组、海水淹溺组及雌激素治疗组.海水淹溺组用气管吸入海水法建立模型;对照组除不吸入海水外,其他处理同海水淹溺组;雌激素治疗组在海水吸入后30 min给予腹腔注射17β-雌二醇5 mg/kg.分别于海水致肺损伤后1、2、4 h时间点取大鼠颈动脉血做血气分析观察动脉血氧分压(PaO2)的变化,测肺组织湿重/干重(W/D)比值,光镜下观察肺组织病理变化情况,采用RT - PCR方法检测AQPs mRNA的表达.结果 成功复制了大鼠海水淹溺型肺损伤模型:海水淹溺组在吸入海水后PaO2显著下降,各时间点PaO2显著低于对照组.雌激素治疗组PaO2显著上升,各时间点均高于海水淹溺组.海水淹溺组W/D比值显著高于正常对照组及雌激素治疗组.光镜下可见海水淹溺组肺组织有灶性出血,肺泡腔内渗出增多、少量中性粒细胞浸润和肺泡间质稍有增厚;对照组未见明显病理变化;雌激素治疗组肺组织充血、水肿有所减轻.海水淹溺组肺组织AQP1 mRNA及AQP5 mRNA表达高于对照组,AQP3 mRNA及AQP4 mRNA无明显变化;雌激素治疗组AQP1 mRNA及AQP5 mRNA表达减少.结论 吸入海水可引起大鼠肺组织AQP1 mRNA及AQP5 mRNA表达增加,但对AQP3 mRNA及AQP4 mRNA表达无明显影响.雌激素通过抑制海水吸入引起的大鼠肺组织AQP1 mRNA及AQP5 mRNA表达上调,影响大鼠海水淹溺型肺损伤时肺组织水的转运. 相似文献
228.
目的探讨超声造影鉴别诊断胰腺假性囊肿、囊腺瘤及囊腺癌的价值。方法回顾性分析2005年2月至2010年8月在我院接受常规超声和超声造影检查的31例胰腺囊性病变患者的临床资料,总结其常规超声和超声造影的图像特点,比较两者在胰腺囊性病变诊断中的价值。结果共发现32个病灶,其中胰腺假性囊肿18个,胰腺囊腺瘤9个,胰腺囊腺癌5个。常规超声及超声造影对胰腺囊性病变的诊断正确率分别为50.0%(16/32)、75.0%(24/32),其差异具有统计学意义(P=0.039)。超声造影在胰腺囊性病变中对胰腺假性囊肿诊断价值最高(Youden指数最高),与本研究诊断标准比较其诊断一致性符合率也最好(Kappa值为0.814)。结论与常规超声比较,超声造影能显著提高胰腺囊性病变的诊断准确率。 相似文献
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手机电视产业未来有庞大的市场,目前国际上还未形成统一技术标准,对我国来说既是机遇也是挑战.论文在对国内外手机电视知识产权和标准现状进行充分调研的基础上,从知识产权和标准战略的视角,对发展我国手机电视产业面临的专利、技术路线、监管政策与产业融合,国家标准制订突出问题进行了深入分析,探讨了推动我国手机电视产业健康、有序发展的途径和对策. 相似文献
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