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991.
目的 探讨超声造影(CEUS)评估慢性肾病(CKD)临床及病理改变的应用价值。 方法 根据CKD分期标准,前瞻性纳入行肾脏穿刺活检及同侧肾脏CEUS检查的CKD 1-3期病人60例,男31例,女29例,平均年龄(40.3±14.3)岁。记录病人的实验室指标[包括血清肌酐(SCr)、血尿素氮(BUN)]、估算肾小球滤过率(eGFR)。采用SonoliverR定量分析软件对造影图像进行后处理,获得相关定量参数,包括峰值强度(Imax)、曲线上升支斜率(A)等。采用单因素方差分析或Kruskal-Wallis H检验比较不同分期CKD病人的CEUS参数,对有差异的CEUS参数采用Bonferroni校正法进行组间两两比较,并与实验室指标、病理评分进行Pearson或Spearman秩相关分析。结果 CEUS参数分析显示,CKD 2、3期病人的Imax值均低于CKD 1期(均P<0.05),3期病人的A值低于1期病人(P<0.05)。相关性分析显示,Imax值与SCr、BUN呈负相关,与eGFR呈正相关(r=-0.350、-0.476、0.485,均P<0.05),A值与eGFR呈正相关(r=0.278,P=0.031);Imax值与肾小球硬化评分呈负相关(r=-0.493,P<0.001),Imax、A值与肾小管萎缩/间质纤维化评分呈负相关(r=-0.398,P=0.002;r=-0.283,P=0.029)。 结论 CEUS能够反映CKD病人肾脏血流灌注的改变,且与临床及病理改变具有一定的相关性,有望成为CKD病人评估及随访的可靠手段。 相似文献
992.
Effect of loading conditions on Doppler-derived transmitral flow indices in normal subjects and patients with coronary artery disease 总被引:3,自引:0,他引:3
Tak T Choudhary RS Chatterjee S Widerhorn J Rahimtoola SH Chandraratna PA 《Echocardiography (Mount Kisco, N.Y.)》1992,9(5):467-474
The influence of alterations in preload and afterload on left ventricular diastolic filling using echocardiography was examined in nine normal volunteers (NLS) and nine patients (PTS) with coronary artery disease. The sequential interventions used were handgrip to increase afterload, nitroglycerin to decrease preload, and nifedipine to decrease afterload. Transmitral flow was measured using pulsed-Doppler echocardiography. Measurements were made pre- and post interventions. With increase in afterload using handgrip, the A and E wave velocities and the A/E ratio increased in both groups: 0.62 +/- 0.14 versus 0.86 +/- 0.17 in NLS; 0.75 +/- 0.45 versus 0.84 +/- 0.50 in PTS (P less than 0.05). Following administration of nitroglycerin to reduce preload, the A wave velocities increased, the E wave velocity decreased in both groups, and the A/E ratio increased 0.57 +/- 0.11 versus 0.67 +/- 0.13 in NLS; 0.78 +/- 0.40 versus 0.91 +/- 0.44 in PTS (P less than 0.05). Following use of nifedipine, the A and E wave velocities decreased in both groups with an increase in the A/E ratio in the patient group 0.83 +/- 0.13 versus 0.89 +/- 0.11 (P = NS). Thus, both normal subjects and patients with coronary artery disease had similar changes in Doppler-derived indices of left ventricular filling following interventions that changed left ventricular preload and afterload. 相似文献
993.
E. Caturelli G. Ghittoni G.A. Niro R. Clemente L. Accadia M. Nardella A. Andriulli M. Anti 《Digestive and liver disease》2006,38(5):347-351
The very rare case of a non-cirrhotic patient with multiple intrahepatic portosystemic and arteriosystemic vascular shunts, presenting with hyperammoniaemic type B encephalopathy and hypoalbuminaemia due to proteinuria, is reported. The correct diagnosis, suspected by abdominal ultrasound and colour-Doppler imaging, was confirmed by hepatic and superior mesenteric angiography. A comparison with the few similar cases existing in the literature is offered. 相似文献
994.
W Mai L Barraud L Lefrancois J Y Scoazec S Guerret D Vray P Merle L Vitvitski-Trepo C Trepo M F Janier 《Liver international》2004,24(6):651-657
AIMS: To evaluate trans-abdominal ultrasound for the detection of Hepatocellular carcinoma (HCC) in a bitrasgenic murine (X/myc) model using a commercially available high-frequency ultrasound unit. METHODS: Sixty-one female animals were included in this study. These animals were submitted to a single ultrasound examination of the liver under general anesthesia (isoflurane), and then euthanized. Results of ultrasound were compared with necropsy and histopathology. RESULTS: The lesions demonstrated a fairly consistent aspect (oval- or round-shaped, well-defined hypoechoic homogeneous lesions), and lesions as small as 2 mm were identified. For detection of hepatic nodules per mouse the sensitivity was 75%, the specificity was 100% and the accuracy was 88.5%. For detection of hepatic focal lesions per lesions the overall sensitivity was 60%, the specificity was 97%, and the accuracy was 75.9%. Contrast-enhanced harmonic ultrasound imaging did not improve the identification of the lesions in our experimental conditions. CONCLUSION: High-frequency ultrasound appears to be an efficient tool allowing new possibilities to use this animal model and evaluate new therapies in longitudinal studies, which are much more powerful. 相似文献
995.
Zenon S. Kyriakides Eftihia Sbarouni Aias Antoniadis Efstathios K. Iliodromitis Dimitrios Mitropoulos Dimitrios T. Kremastinos 《Clinical cardiology》1998,21(10):737-742
Background and hypothesis: In vitro studies have shown that atrial natriuretic peptide (ANP) causes relaxation of pre-constricted blood vessel strips and inhibits the contraction of isolated vessels in response to norepinephrine and angiotensin II. The present study examined the effects of exogenous ANP on the coronary collateral blood flow during angioplasty. Methods: We studied 15 patients undergoing elective balloon angioplasty during the second and third balloon inflations. A Doppler flow guidewire was advanced distal to the lesion and used for the estimation of coronary blood flow velocity. After the second balloon inflation, 25 ng/kg/min of ANP were administered intracoronarily for 8 min. Electrocardiogram, pressure, and flow velocity were recorded immediately before each balloon deflation. Fourteen other patients served as controls and received normal saline infusion. Results: Velocity time integral increased from 65 ± 40 to 79 ± 46 mm (p < 0.05) during the third balloon inflation, whereas ST deviation decreased from 1.3 ± 0.9 to 0.7 ± 1.0 mV (p< 0.05). These variables did not change in the control group during the two tested balloon inflations. Conclusion: Exogenous ANP augments coronary collateral blood flow and ameliorates myocardial ischemia during angioplasty. 相似文献
996.
Vascularity of advanced gastric carcinoma: evaluation by using power Doppler imaging 总被引:1,自引:0,他引:1
Kawasaki T Ueo T Itani T Shibatohge M Mimura J Komori H Todo A Kudo M 《Journal of gastroenterology and hepatology》2001,16(2):149-153
BACKGROUND: We investigated the vascularity of advanced gastric adenocarcinomas by using percutaneous power Doppler imaging. METHODS: Seventeen patients with gastric cancer and 10 without a gastric tumor, but with a slightly thick gastric wall in the B-mode ultrasound, were investigated with the use of power Doppler imaging. The color signals of the gastric lesion were graded as follows: 1, no color signals or the same as the surroundings; 2, color signals were slightly increasing; and 3, color signals were obviously increasing. RESULTS: The color signals of three patients were graded 1, those of eight patients were graded 2 and those of six patients were graded 3 in the gastric cancer group. The color signals of all 10 patients without a gastric tumor were grade 1. This difference was statistically significant (P = 0.0002). CONCLUSIONS: Power Doppler imaging showed vascularity of gastric cancer increasing in the majority of patients (14 of 17: 82%). Thus, power Doppler imaging might be a good screening examination method for gastric cancer. 相似文献
997.
应用岛津SDC-32型线性电子扫描超声波诊断仪,对43例临床确诊的流行性出血热患者进行B超检查,发现均有不同程度的病理声像表现,首次提出了门静脉主干内径增宽现象,并对其临床意义进行探讨。 相似文献
998.
目的探讨腹部超声辅以彩色多普勒检查在诊断老年非均匀性脂肪肝中的应用价值.方法收集23例最终被其他方法确诊为非均匀性脂肪肝的老年患者的肝脏超声图像,回顾性分析这些患者腹部超声以及彩色多普勒的数字和图象资料,找出其内在规律并评价其在诊断老年非均匀性脂肪肝中的应用价值.结果所有23例老年患者腹部超声图象中没有一例患者的腹部超声图象表现为占位效应,其中Ⅰ型局限浸润型2例,Ⅱ型多灶浸润型1例,Ⅲ型叶段浸润型1例,Ⅳ型弥漫非均匀浸润,残存小片正常区19例;彩色多普勒检查示有7例肝内异常强回声或弱回声区(直径均>3.0cm),内部或周边可见正常血管分支走行.结论非占位效应也是老年非均匀性脂肪肝的最重要特征,在诊断老年非均匀性脂肪肝中具有同样高的应用价值. 相似文献
999.
Wiwun Tantibhedhyangkul Warren K Laskey 《Catheterization and cardiovascular interventions》2002,55(3):369-372
Stenosis at the origin of the left internal mammary artery graft is rare. We present a case with a suspected stenosis involving the origin of the left internal mammary artery that conventional angiography failed to demonstrate convincingly. Intravascular ultrasound illustrated a severe stenosis and the patient underwent successful stenting of the left internal mammary artery origin. The intravascular ultrasound finding of a dissection flap, just distal to the left internal mammary artery origin, suggests that local trauma to the vessel from prior catheterization procedures may have been responsible for the progressive narrowing at the left internal mammary artery ostium. 相似文献
1000.
May Sadik Bengt Rundqvist Nedim Selimovic Odd Bech-Hanssen 《European journal of echocardiography》2005,6(3):210-218
BACKGROUND: Echocardiography combining Doppler and two-dimensional data is recommended for quantitative assessments of valvular regurgitation. We applied a new method to calculate the mitral annulus (MA) area in combination with multiple sample sites. Individuals without regurgitation in whom the valvular and left ventricular stroke volumes (SV) should be identical were investigated in order to evaluate the feasibility in quantitative assessments of valvular regurgitation. METHODS AND RESULTS: Twenty subjects were included. Flow velocity was registered with pulsed Doppler in different positions in the left ventricular outflow tract (LVOT) and in the MA. The MA area was assumed to be either circular, using the diameter from a four-chamber projection, or elliptic, using the major diameter from a parasternal short axis and a minor diameter from an apical long axis. Left ventricular (LV) SV was measured from LV volumes using the biplane method. The overall difference between LVOT SV and mitral SV using one centrally located measurement and elliptic MA was 3.2+/-15.6 ml (P=0.38), 0.9+/-15.7 ml between LVOT SV and LV SV (P=0.80) and -2.2+/-15.2 ml between mitral SV and LV SV (P=0.54). The corresponding standard deviation of the differences as a percentage of the mean value was 24%, 25% and 23%. A circular shaped MA overestimated the mitral SV compared with LVOT SV (P=0.009) and LV SV (P=0.004). Increasing the number of sample sites in the LVOT or MA did not further improve the results. CONCLUSION: Doppler and two-dimensional echocardiography can be used to quantify regurgitation in groups of patients. In individual patients the wide distribution of differences between valves and LV SV implies that the method should be used in conjunction with other Doppler echocardiographic parameters. 相似文献