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31.
We assessed the impact of raising the upper section of the bed, and patient positioning, on ultrasound assessment of gastric fluid contents. We performed ultrasound examinations in 25 subjects lying on their back, left and right sides at bed angles of 0°, 30°, 45° and 90°; this was carried out while the subjects were fasted, and repeated 10 min after drinking ≥ 50 ml water. After drinking, gastric contents were detected more frequently in the 45° semirecumbent position compared with the supine and 30° positions. The diagnostic performance of the Perlas qualitative grading scale to detect gastric fluid volume > 1.5 ml.kg−1 was improved at 45°, compared with 0° and 30° angles. The use of a composite ultrasound grading scale at a 45° angle was associated with the best performance, with a sensitivity and specificity of 82%. Antral cross-sectional area was significantly increased when measured in the right lateral position, but there was no effect of raising the bed. In conclusion, raising the upper section of the bed significantly affected qualitative assessment of gastric fluid contents. Further studies are required to determine the most appropriate composite ultrasound grading scale and bed angle for fast and reliable qualitative ultrasound detection of fluid volumes > 1.5 ml.kg−1.  相似文献   
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BackgroundPreclinical studies have demonstrated that high mechanical index (MI) impulses from a diagnostic ultrasound transducer during an intravenous microbubble infusion (sonothrombolysis) can restore epicardial and microvascular flow in acute ST-segment elevation myocardial infarction (STEMI).ObjectivesThis study tested the clinical effectiveness of sonothrombolysis in patients with STEMI.MethodsPatients with their first STEMI were prospectively randomized to either diagnostic ultrasound–guided high MI impulses during an intravenous Definity (Lantheus Medical Imaging, North Billerica, Massachusetts) infusion before, and following, emergent percutaneous coronary intervention (PCI), or to a control group that received PCI only (n = 50 in each group). A reference first STEMI group (n = 203) who arrived outside the randomization window was also analyzed. Angiographic recanalization before PCI, ST-segment resolution, infarct size by magnetic resonance imaging, and systolic function (LVEF) at 6 months were compared.ResultsST-segment resolution occurred in 16 (32%) high MI PCI versus 2 (4%) PCI-only patients before PCI, and angiographic recanalization was 48% in high MI/PCI versus 20% in PCI only and 21% in the reference group (p < 0.001). Infarct size was reduced (29 ± 22 g high MI/PCI vs. 40 ± 20 g PCI only; p = 0.026). LVEF was not different between groups before treatment (44 ± 11% vs. 43 ± 10%), but increased immediately after PCI in the high MI/PCI group (p = 0.03), and remained higher at 6 months (p = 0.015). Need for implantable defibrillator (LVEF ≤30%) was reduced in the high MI/PCI group (5% vs. 18% PCI only; p = 0.045).ConclusionsSonothrombolysis added to PCI improves recanalization rates and reduces infarct size, resulting in sustained improvements in systolic function after STEMI. (Therapeutic Use of Ultrasound in Acute Coronary Artery Disease; NCT02410330).  相似文献   
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目的建立一种汉滩型汉坦病毒(Hantaan virus,HTNV)荧光定量(RT-PCR)的检测方法,以便快速准确地检测HTNV。方法利用Beacon Designer7.0设计引物和探针,以HTNV的S基因片段为模板,进行实时荧光定量RT-PCR,评价此方法的特异性及灵敏度。结果建立的RT-PCR方法对HTNV的最低检出限为4.08copies/μL,模板Ct值与稀释浓度的对数之间具有良好的线性关系,标准曲线方程为Y=-3.4118X+41.997,扩增效率为96.4%,R2=0.994。结论所建立的实时荧光定量RT-PCR检测方法灵敏度高、特异性好,可应用于HTNV的快速检测。  相似文献   
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目的:探讨彩色多普勒超声检查在提高致密型乳腺癌患者术后对侧乳腺癌(contralateral breast cancer,CBC)检出率中的应用价值。方法:对我院乳腺癌患者行术后常规乳腺超声及钼靶检查,229名患者考虑对侧乳腺病变,根据腺体含量对其进行分型,并应用BI-RADS分级对病变进行评估。结果:超声诊断CBC的特异性、准确率与阳性预测值均明显好于钼靶检查,致密型乳腺钼靶CBC检出率明显下降,超声检查CBC检出率明显增高,BI-RADS 4A与4B分级中脂肪型及少量腺体型乳腺钼靶CBC的检出率明显高于超声检查,BI-RADS 4C与5分级中,乳腺分型对超声及钼靶筛查CBC的结果影响不大。结论:超声及钼靶的联合检查在CBC的检出中发挥重要作用,而乳腺分型与BI-RADS分类诊断对乳腺肿瘤的临床诊断效能和应用价值意义重大。  相似文献   
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Portal venous gas is occasionally encountered in children with intestinal pneumatosis, identified on real‐time ultrasound imaging as hyperechoic foci with quick movement. The origin of the portal venous gas can be identified by following the hyperechoic foci along the branches of the portal vein, providing an estimate of the location of intestinal pneumatosis. This approach may be useful for predicting the patient's prognosis. Our report describes 2 cases of portal venous gas while estimating the area of intestinal pneumatosis, which were evaluated with real‐time ultrasound.  相似文献   
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