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Radiologic diagnosis of an intra-abdominal abscess. Do multiple tests help?   总被引:2,自引:0,他引:2  
A review was made of the charts of 94 patients who underwent ultrasonography (US), computed tomography (CT), and gallium citrate Ga 67 (Gall) scan to rule out intra-abdominal abscesses. Of all the clinical and laboratory data, only the presence of pain and tenderness differentiated patients with and without abscesses. A review of radiologic data showed that CT was superior to US, and that US was superior to Gall scan with regard to sensitivity, specificity, accuracy, and positive and negative predictive values. When multiple radiologic tests were performed, results agreed in 72% of cases; therefore, the additional tests were essentially redundant. When radiologic test results disagreed, accuracy rates were CT, 0.86; US, 0.00; and Gall scan, 0.44. These findings suggest that, except to rule out pelvic abscesses in the presence of pelvic inflammatory disease, CT is usually the only special radiologic test that should be performed to localize a suspected intra-abdominal abscess.  相似文献   
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Summary: The morphology of the transcrystalline layer grown by nucleating high density polyethylene on fibers of ultra high molecular weight polyethylene was investigated by microbeam synchrotron X‐ray diffraction. Scanning with a 2 micron step size, it was possible to determine that near the fiber surface, the polymer chains of the transcrystalline layer are oriented at an angle of approx. 41° with respect to the fiber axis. This is consistent with the lamellar fold surface (the {201} plane) being close to perpendicular to the fiber axis. The X‐ray data support gradual twisting of the lamellae about the growth direction (the orthorhombic crystallite b‐axis) at a rate of ~0.85° per micron of radial distance from the fiber surface.

Polarized light micrograph of the transcrystalline layer in a PE/PE composite. The width of the fiber is approximately 20 μm.  相似文献   

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Mutations in the MYOC gene may lead to juvenile open-angle glaucoma with high intraocular pressure, and are detected in about 4% of people with adult onset glaucoma. Most of these mutations are found in the third exon of the gene encoding the olfactomedin-like domain located at the C terminus of the protein. Another olfactomedin-related protein, known as noelin or pancortin, is involved in the generation of neural crest cells. Here we describe the identification of a novel olfactomedin-related gene, named optimedin, located on chromosome 1p21 in humans. Optimedin and noelin are both expressed in brain and retina. However, unlike noelin, rat optimedin is also highly expressed in the epithelial cells of the iris and the ciliary body in close proximity to the sites of Myoc expression. In the human eye, optimedin is expressed in the retina and the trabecular meshwork. Both optimedin and myocilin are localized in Golgi and are secreted proteins. The presence of mutant myocilin interferes with secretion of optimedin in transfected cells. Optimedin and myocilin interact with each other in vitro as judged by the GST pulldown, co-immunoprecipitation and far-western binding assays. The C-terminal olfactomedin domains are essential for interaction between optimedin and myocilin, while the N-terminal domains of both proteins are involved in the formation of protein homodimers. We suggest that optimedin may be a candidate gene for disorders involving the anterior segment of the eye and the retina.  相似文献   
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Interactions between the carbonyl and amino groups in copolymers of 2-dimethylaminoethyl methacrylate with N-phenylmaleimide are reported. The existence of interactions ensues from potentiometric measurements and UV-VIS spectra. Interactions in these copolymers result in the formation of energetically very advantageous chromophores, reflected in an intense red colour of the substances obtained.  相似文献   
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