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OBJECTIVE: To evaluate the pattern of contrast enhancement with Levovist on coded harmonic angiographic ultrasonography of hepatic hemangiomas. METHODS: Twenty hemangiomas were evaluated with coded harmonic angiographic ultrasonography and a microbubble contrast agent. Verification of the diagnosis of a hemangioma was made by means of dynamic computed tomography (n = 8), dynamic magnetic resonance imaging (n = 1), radionuclide scanning (n = 6), or follow-up ultrasonography (n = 5). Ultrasonographic images were obtained before contrast agent administration and with a bolus injection of 2.5 g of a microbubble contrast agent (300 mg/mL Levovist; Schering AG, Berlin, Germany) every 10 to 15 seconds for 5 minutes. The contrast enhancement patterns of the 20 hemangiomas were assessed. RESULTS: The tumor diameters as measured on ultrasonography were 7 to 97 mm (mean, 26.7 mm). Of the 20 hemangiomas, peripheral globular enhancement with progressive centripetal fill-in was shown in 15 (75%), rimlike enhancement with progressive centripetal fill-in was shown in 2 (10%), and homogeneous enhancement was shown in 1 (5%). In the remaining 2 lesions (10%), the enhancement patterns could not be seen, because they were not found on coded harmonic angiographic ultrasonography. CONCLUSIONS: Coded harmonic angiographic ultrasonography with a microbubble contrast agent can depict the typical enhancement pattern in most hepatic hemangiomas.  相似文献   
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BACKGROUND: Practitioners are being encouraged to base their clinical practice on research evidence. In order to do this, they must be aware of and use the sources of evidence. METHODS: A questionnaire survey was undertaken to establish GPs' awareness of research evidence in their clinical practice and, in fundholding practices, its influence on purchasing plans. Questionnaires were sent to 360 lead fundholders in North Thames Region and 440 of a random sample of the remaining general practitioners in the region for comparison. RESULTS: Questionnaires were returned by 62% of lead fundholders and 63% of GPs in the random sample. There was limited use of the electronic sources of clinical effectiveness. There was greater reported awareness of published sources of research evidence and fundholding GPs were significantly more likely to have referred to publications summarizing research evidence. CONCLUSIONS: GPs seem to make more use of published clinical effectiveness sources than the electronic databases. Consequently, they need educational and technical support if they are to make full use of the available sources of research evidence available in other media.   相似文献   
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One cDNA clone was purified from an adult Clonorchis sinensis cDNA library, and its deduced polypeptide sequence was found to be homologous with myosin regulatory light chain (MRLC) of invertebrates and vertebrates. Two amino-acid residues, Thr and Ser, were conserved at the phosphorylation sites that regulate the function of MRLCs. Recombinant C. sinensis MRLC (rCsMRLC) protein was produced and purified from Escherichia coli, and mouse anti-CsMRLC immune sera recognized a protein of molecular weight 24 kDa from a soluble protein preparation of C. sinensis. The CsMRLC protein was immunohistochemically localized to the muscle fibers of the subtegumental muscle layer and to the muscles of oral and ventral suckers. However, the rCsMRLC protein proved to be less useful antigen for the serodiagnosis of human clonorchiasis.The nucleotide sequence reported herein was submitted to GenBank and assigned accession number AY519356.  相似文献   
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We describe a novel method of reconstructing images of an anisotropic conductivity tensor distribution inside an electrically conducting subject in magnetic resonance electrical impedance tomography (MREIT). MREIT is a recent medical imaging technique combining electrical impedance tomography (EIT) and magnetic resonance imaging (MRI) to produce conductivity images with improved spatial resolution and accuracy. In MREIT, we inject electrical current into the subject through surface electrodes and measure the z-component Bz of the induced magnetic flux density using an MRI scanner. Here, we assume that z is the direction of the main magnetic field of the MRI scanner. Considering the fact that most biological tissues are known to have anisotropic conductivity values, the primary goal of MREIT should be the imaging of an anisotropic conductivity tensor distribution. However, up to now, all MREIT techniques have assumed an isotropic conductivity distribution in the image reconstruction problem to simplify the underlying mathematical theory. In this paper, we firstly formulate a new image reconstruction method of an anisotropic conductivity tensor distribution. We use the relationship between multiple injection currents and the corresponding induced Bz data. Simulation results show that the algorithm can successfully reconstruct images of anisotropic conductivity tensor distributions. While the results show the feasibility of the method, they also suggest a more careful design of data collection methods and data processing techniques compared with isotropic conductivity imaging.  相似文献   
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International Urology and Nephrology - A systemic inflammation response index (SIRI) has been recently introduced as a tool for the assessment of the prognosis of several critical medical...  相似文献   
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