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81.
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Objective - Ultrasonographic assessment of carotid artery plaque morphology is widely used to identify patients at high risk for stroke. However, the reliability of plaque analysis in high-grade stenosis is uncertain. We determined the interrater reliability of sonographic plaque morphology analysis in patients with severe carotid artery stenosis. Material and methods - Duplex Doppler was performed on 114 patients with 80–99% stenosis of the internal carotid artery using a Siemens Quantum 2000 D with a handheld 7.5 MHz transducer. B-mode pictures with and without color coding were printed on a Sony color video printer UP-5000 W. Three raters independently evaluated plaque echolucency, heterogeneity, calcification, and surface structure. Interrater agreement was calculated by a jackknife procedure generating kappa values and two-sided 95% confidence intervals. Results - Kappa values and 95% confidence intervals were 0.05 (-0.07 to 0.16) for plaque surface structure, 0.15 (0.02 to 0.28) for plaque heterogeneity, 0.18 (0.09 to 0.29) for plaque echogenicity, and 0.29 (0.19 to 0.39) for plaque calcification. The upper bounds of all of the confidence intervals were below the 0.40 level suggested for minimal reliability. Conclusion - The low interrater agreement indicated that unaided visual assessment of static B-mode pictures to assess plaque morphology in patients with severe carotid artery stenosis is not reliable. Other evaluation procedures and standardized criteria, as yet undeveloped, are needed to improve reliability.  相似文献   
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The radiographic findings in five pediatric patients in whom unregulated B-cell lymphoproliferative disorders developed following bone marrow transplantation are described. Four patients received T-cell-depleted bone marrow from mismatched donors and one received nondepleted marrow from a matched sibling donor. These disorders are similar to B-cell lymphoproliferative disorders that have been described in other immunosuppressed hosts. They are associated with Epstein-Barr virus and range from polyclonal proliferation without cytogenetic abnormalities to monoclonal lymphoma with clonal cytogenetic changes. Unlike other postallograft lymphoproliferative processes, B-cell lymphoproliferative disorders in these patients have not responded to antiviral therapy, immunologic therapy, or chemotherapy. The radiographic patterns of disease include diffuse or focal hepatic involvement; gallbladder wall thickening; and pulmonary, soft-tissue, and basal-ganglion masses. These radiologic findings are not specific and evaluation of tissue histology is required for diagnosis.  相似文献   
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急性呼吸窘迫综合征(acute respiraory distress syndrome,ARDS)是一种常见的严重肺功能紊乱的肺部并发症。常并发于脓毒血症、创伤和抽吸术等严重损伤后。ARDS的发生及死亡率可因发生ARDS损伤类型的不同而有差别,提示ARDS的发病机制和预后因临床风险因素而不同。最近,对重症病人进  相似文献   
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Plasma-derived alpha 1-proteinase inhibitor (alpha 1PlI) is used for replacement therapy in patients with emphysema who have a deficiency of the protein. Future therapy with alpha 1PI with reactive site mutants of this inhibitor will probably require the use of recombinant-derived alpha 1PI (r alpha 1PI). However, the pharmacologic efficacy of r alpha 1PI in humans has been hindered, since r alpha 1PI is rapidly cleared from the circulation of experimental animals. Our studies of the metabolism of r alpha 1PI in mice demonstrate that the rapid clearance of r alpha 1PI is due to renal filtration. However, after preventing renal filtration by ligation of the renal arteries, we find that r alpha 1PI is metabolized in a manner similar to alpha 1PI. Conjugation of r alpha 1PI to polyethylene glycol of Mr approximately 4000 (PEG-4) greatly slows the clearance of r alpha 1PI. The PEG-4 r alpha 1PI conjugate is metabolized in a manner similar to alpha 1PI and has similar kinetic properties before and after oxidation with N-chlorosuccinimide. Moreover, proteinase complexes of PEG-4-r alpha 1PI are catabolized by the same hepatocyte receptor that binds alpha 1PI-proteinase complexes. The results of these studies lay the groundwork for the synthesis of pharmacologically effective r alpha 1PI derivatives with acceptable plasma retention times.  相似文献   
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Bovine papular stomatitis virus was isolated from two calves in an animal house with biosafety level 3 confinement. The hypotheses on the origin of the infection, the interesting features of the partial amino acid sequences of the major envelope viral protein, and the importance of diagnostic tools available for animal diseases that are not listed by the World Organization for Animal Health (OIE) are discussed.  相似文献   
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Huntington's disease is characterized by motor, cognitive, and neuropsychiatric symptoms. This study reviews original research on psychopathology in Huntington's disease that uses standardized instruments in verified gene carriers. Frequently reported neuropsychiatric symptoms are depressed mood, anxiety, irritability, and apathy, with prevalences of 33% to 76%. Obsessive-compulsive symptoms and psychosis occur less often with prevalences of 10% to 52% and 3% to 11%, respectively. Available research provides little insight into the true prevalences of psychopathology in Huntington's disease due to small sample sizes, use of different methodologies, and lack of comparison groups. Future research requires larger cohorts stratified to disease stage, consistent methodologies, and adequate comparison groups.  相似文献   
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