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51.
The cytotoxic and anti-proliferative effects of high-energy pulsed ultrasound (HEPUS) on human squamous cell carcinoma cells cloned from the hypopharynx (FaDu) and benign connective tissue cells (fibroblasts) were investigated in vitro. Sonication was carried out using an experimental piezoelectric, self-focusing burst-signal transducer. To increase the induction of cavitation, the transducer used was specifically designed to produce multiple oscillations with a high negative pressure amplitude. In both cell lines tested, the application of 100, 800 and 2000 pulses resulted in a high reduction of vital cells. After 2000 pulses, 4.0 ± 1.1% of the fibroblasts but only 2.0 ± 0.4% of the FaDu cells survived HEPUS exposure. A postexposure inhibiting effect of HEPUS for 10 days on the proliferation of surviving cells was noted for the FaDu cells exposed to 2000 pulses, but not as much for the fibroblasts. These findings support the hypothesis that human squamous cell carcinoma cells of the hypopharynx might be more sensitive to HEPUS than fibroblasts and that total tumor cell ablation might be possible in vitro given a sufficient number of HEPUS pulses. Received: 18 November 1997 / Accepted: 21 April 1998  相似文献   
52.
血清CA125结合B超对绝经后妇女卵巢恶性病变的预测价值   总被引:1,自引:0,他引:1  
目的 通过了解绝经后妇女卵巢肿物的临床特点,探讨早期发现绝经后妇女卵巢恶性肿瘤的可行方法。方法 回顾分析302例经手术后病理证实为卵巢肿物的自然绝经后妇女的临床特点,采用B超结合血CA125的定量测定。结果 71.2%的绝经后卵巢肿物患者无自觉症状,38.7%为卵巢恶性肿瘤,BUS结合血CA125对卵巢恶性病变预测的敏感性为98.4%,特异性为57.9%,阳性预测值62.6%,阴性预测值98.1%。结论 对绝经后妇女实施妇科检查及B超的筛查结合血CA125的定量测定,有助于临床医生及时发现卵巢恶性肿瘤。  相似文献   
53.
OBJECTIVES: To investigate the impact of an ultrasound dating service on obstetric services. METHODS: A prospective trial with 3009 unselected women presenting for antenatal care at two Midwife Obstetric Units in a socioeconomically deprived urban area, South Africa. In the study unit, student ultrasonographers provided a basic ultrasound service. In the control unit, obstetric ultrasound was only available for specific indications. The main outcome measures were number of antenatal visits and referrals for fetal surveillance. RESULTS: The two cohorts were comparable except for the number of primigravidas but stratified analysis according to parity did not affect the results. Ultrasonography did not alter pregnancy outcome but reduced the number of perceived preterm labors/ruptured membranes (12.0 vs. 16.7%, P<0.003), post-term deliveries (8.1 vs. 10.8%, P<0.04) and referrals for fetal surveillance [15.9 vs. 29.6%, P<0.000, RR 0.79 (0.71-0.88)]. CONCLUSIONS: This community-based basic ultrasound service significantly reduced referrals to a regional center for fetal surveillance and delivery.  相似文献   
54.
The purpose of this debate is to argue the merits of whether the availability of 24-hour transvaginal ultrasound service in every unit will help predict and, subsequently, prevent preterm birth. Any new test introduced will need to fulfil certain criteria. It must be acceptable in terms of risk, cost and patient convenience. It must be an improvement over existing alternatives, and it must aid clinicians to improve care. While the 24-hour availability of transvaginal ultrasound to every maternity unit may be useful to research and teaching, there is, as yet, little evidence that a 24-hour transvaginal ultrasound service improves perinatal and maternal morbidity and mortality. Results from our own centre suggest that experienced clinicians can make an acceptable diagnosis of spontaneous preterm labour (PTL) using only history and digital examination. Based on these findings, the availability of 24-hour vaginal ultrasound in every unit cannot be justified for the diagnosis of spontaneous PTL.  相似文献   
55.
The usefulness of the vascular ultrasound in the field of obstetrics is now well recognized. Intima-media thickness (IMT) and elastic property of the common carotid artery are affected by pregnancy and vary with complications. Flow-mediated vasodilation (FMD) of the brachial artery reflects the vascular endothelial function and is reported to be useful in the management of complicated pregnancy, especially pre-eclampsia. For the screening of deep vein thrombosis of the lower extremities in the perinatal period, compression ultrasonography (CUS) is useful.  相似文献   
56.
Tear of the distal biceps brachii tendon is an uncommon injury. Ultrasound evaluation of the distal tendon using an anterior approach is often difficult because of technical factors. We describe a new method of ultrasound evaluation of the distal biceps tendon insertion. This involves a posterior approach with the forearm pronated. With pronation of the forearm, the radial tuberosity faces posteriorly, bringing the distal biceps tendon insertion into view. A surgically proven case of distal biceps tendon tear is presented to illustrate our technique.  相似文献   
57.
Differentiation of abdominal masses detected on prenatal ultrasound is difficult and requires careful characterization of the mass and precise localization. Differentiation is required in order to distinguish benign from potentially malignant conditions. We describe a case of fetus‐in‐fetu with pre and postnatal imaging.  相似文献   
58.
目的 采用 Meta 分析方法来评价肺脏超声对新生儿肺炎的诊断价值。方法 检索PubMed、Cochrane library、Embase、CNKI 和万方数据库,按照诊断性试验的纳入和排除标准,获取符合本研究要求的文献,检索时间为建库至 2018年9月。共检索到907篇文献,选取其中8篇进一步分析,并对文献质量进行QUADAS2标准评价,采用Q检验和I 2统计量进行异质性检验,采用 Meta-Disc 1.4 软件进行统计学分析,评价肺脏超声对新生儿肺炎的诊断价值。 结果 共纳入8篇文献、1078例。采用随机效应模型对纳入的研究进行统计分析,合并敏感度为0.96(95%CI:0.95~0.98),合并特异度为0.98(95%CI:0.95~0.99),合并阳性似然比为19.52(95%CI:5.00~76.15),合并阴性似然比为0.04(95%CI:0.01~0.16),合并诊断优势比为565.45(81.80~3908.58),拟合ROC 曲线下面积0.9950。结论 肺脏超声诊断新生儿肺炎的敏感度和特异度较X线高。鉴于其相对容易操作、实时可用、低成本和无电离辐射,目前的证据支持超声作为新生儿肺炎诊断的替代手段。  相似文献   
59.
The involvement of ankles in systemic lupus erythematosus (SLE) has not been widely studied. The aim of our prospective study was to determine the characteristics of the ankle joint and tendon involvement in SLE using ultrasound (US) as an imaging modality. Sixty consecutive patients with SLE underwent a detailed clinical evaluation and US examination. Gray-scale and power Doppler US of the bilateral tibiotalar (TT) joints, subtalar (ST) joints, and ankle tendons were performed using a multiplanar scanning technique. Joint effusion, synovitis, tenosynovitis, enthesitis, and vascularization were assessed according to the OMERACT recommendations. The Total Ankle Ultrasound Score (TAUSS) was calculated as the sum of the grades of joint effusion and synovial hypertrophy for both TT and ST joints bilaterally (ranging from 0–24) and power Doppler activity was assessed separately. Finally, US findings were correlated with physical evaluation, laboratory parameters, and SLE activity scores. US ankle joint involvement was present in 32/60 (53.3%) patients. TT joints were affected in 26 (43.3%) and ST joints in 16 (26.7%) patients. Thirteen (21.7%) patients had US tendons and/or enthesal involvement. TT joint effusion was the most frequent finding, present in 55/240 (22.9%) examined joints, followed by synovial hypertrophy detected in 18/240 (7.5%) joints. The median (interquartile range; range) TAUSS of the US-affected joints was 1 (0–2; range 1–10). There were no significant correlations between US findings and inflammatory parameters or serological parameters of disease activity, but we found a weak positive correlation between TAUSS and the European Consensus Lupus Activity Measurement (r = 0.281, P = .029). This study revealed a high prevalence of pathological US ankle changes in patients with SLE and a positive correlation between ankle US involvement and disease activity score (European Consensus Lupus Activity Measurement).  相似文献   
60.
目的探讨胃镜、B超、CT在进展期胃癌诊断、治疗中的应用价值。方法回顾性分析112例经手术及病理证实的进展期胃癌的胃镜、B超、CT资料。结果112例进展期胃癌,胃镜符合率为100%(112/112),B超符合率96.4%(108/112),CT符合率98.2%(110/112);恶性肿瘤TNM分期:B超符合率78.6%(88/112),CT符合率83.0%(93/112)。结论胃镜检查结合黏膜活检仍然是进展期胃癌首选检查手段,B超、CT检查可对胃癌进行术前TNM分期,三者合理应用能更好地提高进展期胃癌的诊断、指导临床治疗、术后疗效观察及预后判断水平。  相似文献   
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