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21.
Focal liver masses: differential diagnosis with pulsed Doppler US   总被引:8,自引:0,他引:8  
Duplex Doppler ultrasound (US) was used in 68 consecutive patients with focal liver lesions, including 12 hepatocellular carcinomas, one cholangiocarcinoma, 37 metastases, 15 hemangiomas, one hemangioendothelioma, and two focal nodular hyperplasias. Of the hepatocellular carcinomas, six were diffusely hyperechoic, two were hypoechoic, two were single hyperechoic lesions, and two were multifocal and hyperechoic. All ten tumors with Doppler shifts of 5 kHz or above proved to be hepatocellular carcinomas. The other two hepatocellular carcinomas showed Doppler shifts of 3 kHz. In contrast, no hemangioma showed shifts above 0.7 kHz, and ten of the 15 gave no detectable signal. Of the metastases, 20 gave no signal and 17 had signals of up to 4 kHz. Three-kilohertz signals were also obtained from a cholangiocarcinoma, a hemangioendothelioma, and focal nodular hyperplasia. Correlation with angiographic findings suggested that the high-velocity Doppler signals were associated with large pressure gradients due to arteriovenous shunting. Duplex Doppler US can therefore aid in the differential diagnosis of diffuse and focal liver lesions.  相似文献   
22.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
23.
Aim:  The classical combination of abdominal pain, vomiting, rectal blood loss and a palpable abdominal mass is only present in a minority of children with intussusception. Neurological signs and symptoms have been described, but are not a well understood phenomenon. We performed a retrospective study to ascertain the frequency and nature of these symptoms and to describe the characteristics of the patients presenting in this atypical way.
Methods:  The records of 58 children presenting with intussusception from 2003 to 2008 were reviewed for abdominal and neurological signs and symptoms, duration of symptoms and effectiveness of treatment.
Results:  In 10 out of 58 patients (17%), one or more neurological symptoms were recorded at presentation, with lethargy being the most frequent, followed by hypotonia and fluctuating consciousness. The patients with neurological abnormalities were significantly younger and presented with a shorter duration of symptoms. Therapy was more invasive, although not statistically significant, in this patient category.
Conclusion:  Intussusception should be considered in the differential diagnosis in young children presenting with lethargy, hypotonia and/or sudden alterations of consciousness even in the absence of the classical symptoms of intussusception.  相似文献   
24.
Rademaker KJ, Groenendaal F, Jansen GH, Eken P, de Vries LS. Unilateral haemorrhagic parenchymal lesions in the preterm infant: shape, site and prognosis. Acta Pædiatr 1994;83:602–8. Stockholm. ISSN 0803–5253 In a prospective cranial ultrasound study of 544 infants with a gestational age of 32 weeks or less, 20 (3.6%) infants were diagnosed as having a unilateral parenchymal lesion (PL). Based on the shape of the PL and the evolution on ultrasound, the infants were divided into three groups: group I consisted of 11 infants, in whom the PL was triangular/fan-shaped and separate from the ventricle. The PL evolved into small cystic lesions; group II comprised 3 infants who had a PL with a similar shape, but partially communicating with the ventricle; group III consisted of 6 infants who had a globular-shaped lesion in communication with the ventricle. In groups II and III, the PL evolved into one porcncephalic cyst. The PL was considered to be due to venous infarction in all cases with intraventricular haemorrhage preceding the PL in 7 cases. Sixteen infants survived. A postmortem was performed in 2 of the 4 infants who died, confirming the diagnosis of venous infarction. Neurologicdl sequelae were present in only 2 cases in the first group, while all 6 survivors of the other two groups developed mild to severe hemiplegia. Long-term follow-up was not always available and 4 of the 18 survivors were still less than 18 months when last seen. In 9 of the 11 infants in group I, the PL was localized in the frontoparietal region, while in 8 of the 9 infants in group II or III, the PL was beyond the trigone in the occipital region. The outcome of the unilateral PL is not always unfavourable. It was evident that not only the shape of the lesion and whether or not there was communication with the lateral ventricle, but also the site of the lesion (whether or not it extended into the occipital periventricular white matter) appeared to be important with regard to neurodevelopmental outcome.  相似文献   
25.
Newlin  N; Silver  TM; Stuck  KJ; Sandler  MA 《Radiology》1981,139(1):155-159
Ultrasonic features of 21 surgically confirmed pyogenic liver abscesses in 18 patients were analyzed. Typical lesions were round or ovoid with a discrete, irregular, echo-poor margin. The number and intensity of internal echoes and sound transmission were variable. Such lesions can be aspirated percutaneously for definitive preoperative diagnosis. Pyogenic liver abscesses appear to have more ragged walls and are less frequently elliptical or multilocular than abscesses elsewhere in the abdomen.  相似文献   
26.
Clinical use of atrial pacing test in angina pectoris   总被引:3,自引:0,他引:3  
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27.
Anatomy and pathology of the kidney by gray scale ultrasound   总被引:1,自引:0,他引:1  
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28.
29.
Analysis of H-2 class I-specific cDNA clones has suggested the synthesis by the liver of a class I molecule that is secreted rather than membrane bound. To detect this putative class I-related molecule, we have predicted a unique region of amino acid sequence located toward the carboxyl terminus of the molecule that is not expected to be shared with any of the classical H-2 class I antigens, and we have generated specific antibodies to a synthetic peptide corresponding to this sequence. Indirect immunoprecipitation with this antibody led to the identification of a Mr 40,000 polypeptide in association with beta 2-microglobulin in the serum of mice of five different H-2 haplotypes. This class I molecule is also detected in the liver together with lower molecular weight components, which are presumably underglycosylated precursors. Synthesis of this molecule is not detected in thymus, spleen, kidney, or testis. This class I serum component has no detectable reactivity with either a broad-specificity alloantiserum against H-2b or a xenoantiserum against purified H-2a class I molecules. The availability of a specific antibody against the secreted class I molecule offers a means to purify this protein for structural and functional studies.  相似文献   
30.
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