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81.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
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83.
Serologic studies using four murine monoclonal antibodies specific for the common acute lymphoblastic leukemia antigen (CALLA) and five monoclonal antibodies specific for the gp24 surface antigen indicate that these leukemia-associated antigens are present on cells of comparable tissues in man and in four nonhuman primates. As in man, adherent cell populations obtained from skin, lung, and bone marrow of Macaca fascicularis, M mulatta, M nemestrina, and Papio cynocephalus react with these antibodies. Similarly, granulocytes from both man and these nonhuman primates bind CALLA- and gp24-specific antibodies. Radioimmune precipitation experiments confirm the identity of these antigens. Our studies suggest that nonhuman primates can be used to screen serologic reagents to leukemia-associated antigens for potential toxic effects on normal tissues prior to their use in man. Similarly, nonhuman primates could be employed to assess the possible role of antigen-positive stromal cells in the reconstitution of bone marrow following transplantation. 相似文献
84.
JM Leppilahti M‐M Ahonen M Hernández S Munjal L Netuschil V‐J Uitto T Sorsa P Mäntylä 《Oral diseases》2011,17(1):115-122
Oral Diseases (2010) 17 , 115–122 Objective: To determine whether oral rinse matrix metalloproteinase (MMP)‐8 levels, measured by three different methods, tissue inhibitor of matrix metalloprotease‐1 (TIMP‐1) levels and elastase activity differentiate subjects with different periodontal condition; and second, to find out if MMP‐8 levels were comparable among the methods used. Methods: MMP‐8 levels were analysed with an immunofluorometric method (IFMA), dentoELISA and commercial ELISA. Also TIMP‐1 levels and elastase activity were measured. For statistical analysis 214 study subjects were categorized into four groups, specified by the presence and number of moderate (4–5 mm) and deep (≥6 mm) periodontal pockets, and bleeding on probing percentage. Results: MMP‐8 levels especially measured by dentoELISA and adjusted to the number of teeth per subject differentiated the study group with strong periodontal inflammatory burden from groups with lower levels. This was also verified with receiver operating characteristic ( ROC) analysis. Elastase activity associated with higher IFMA and dentoELISA MMP‐8 levels. IFMA MMP‐8/TIMP and dentoELISA MMP‐8/TIMP‐1 tended to be higher with the increasing level of periodontal inflammatory burden. TIMP‐1 levels decreased with increasing age. Conclusions: Oral rinse MMP‐8 together with TIMP‐1 analysis may have potential in complementary periodontal diagnostics. dentoELISA can be applied in quantitative oral rinse chair side biomarker diagnostics. 相似文献
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86.
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
87.
MR Danzig RA Ghandour P Chang AA Wagner PM Pierorazio ME Allaf JM McKiernan 《Urologic oncology》2017,35(3):116
Purpose
We compared renal function outcomes among patients in the surveillance and intervention arms of the DISSRM registry.Materials and methods
Patients were grouped into chronic kidney disease stages by estimated glomerular filtration rate range. Cases were considered up staged if a more advanced chronic kidney disease stage was entered during followup. Chronic kidney disease up staging-free survival was compared among groups using Kaplan-Meier analysis and paired comparisons log rank tests. Multivariate Cox regression identified independent predictors of chronic kidney disease up staging-free survival.Results
A total of 162 patients met the study inclusion criteria, with 68 in the surveillance arm, 65 undergoing partial nephrectomy, 15 undergoing radical nephrectomy, and 14 undergoing cryoablation. Median tumor size was 2.2 cm. Mean estimated glomerular filtration rate change was significantly larger for radical nephrectomy vs. surveillance (?9.2 vs. ?0.5 ml/min/1.73 m2) and for radical vs. partial nephrectomy (?9.2 vs. ?1.9 ml/min/1.73 m2) (P = 0.001). No other groups differed significantly. On Kaplan-Meier analysis, patients undergoing radical nephrectomy had significantly worse chronic kidney disease up staging-free survival vs. those treated with partial nephrectomy (P = 0.029), surveillance (P = 0.007), and cryoablation (P = 0.019). No other groups differed significantly. On multivariate analysis, radical nephrectomy independently predicted poor chronic kidney disease up staging-free survival (odds ratio vs. surveillance 30.6, P = 0.001). Neither partial nephrectomy (P = 0.985) nor cryoablation (P = 0.976) predicted poor chronic kidney disease up staging-free survival relative to surveillance.Conclusions
Patients in the surveillance arm had superior estimated glomerular filtration rate preservation compared to those in the radical nephrectomy but not the partial nephrectomy arm. In certain patients with small renal masses, surveillance and partial nephrectomy may offer comparable renal functional outcomes. This could be partly attributable to a modest estimated glomerular filtration rate decrease associated with surveillance itself. A thorough understanding of the renal functional impacts of treatment modalities is critical in the management of small renal masses. 相似文献88.
A significant proportion of hemophilia A patients receiving transfusions of factor VIII (FVIII) develop a specific antibody response towards FVIII. These antibodies are usually detected by assays in which they inhibit the function of the molecule, such as the Bethesda clotting test. We have prepared anti-FVIII antibodies by specific immunoadsorption from the plasma of four hemophiliacs with stable inhibitor levels. The isotypic distribution of such antibodies was determined and their capacity to bind to insolubilized FVIII was compared with their inhibitory activity in two functional assays, namely, the Bethesda assay and a chromogenic assay. In addition, the FVIII epitope specificity was determined by competition with monoclonal antibodies for the binding to insolubilized FVIII. We show here that (1) anti-FVIII antibodies are not isotypically restricted; thus, a significant proportion of specific IgG2 was found; (2) antibodies are frequently directed towards epitopes of FVIII that are not directly involved in the function of the molecule and therefore escape detection in the Bethesda method or chromogenic assay; and (3) each patient shows a unique pattern of FVIII epitope recognition. We conclude that evaluation of anti-FVIII antibodies by a functional method does not provide an accurate evaluation of the specific antibody response. These findings have important implications for the comparison of the immunogenicity of FVIII molecules produced by different technologies and for the development of methods to control anti-FVIII antibody production. 相似文献
89.
Vena Tech-LGM filter: long-term results of a prospective study 总被引:12,自引:0,他引:12
Crochet DP; Stora O; Ferry D; Grossetete R; Leurent B; Brunel P; Nguyen JM 《Radiology》1993,188(3):857
90.
Susanne J van Veluw Jaco JM Zwanenburg Annemieke JM Rozemuller Peter R Luijten Wim GM Spliet Geert Jan Biessels 《Journal of cerebral blood flow and metabolism》2015,35(4):676-683
Cerebral microinfarcts (CMIs) are common neuropathologic findings in aging and dementia. We explored the spectrum of cortical CMIs that can be visualized with 7T magnetic resonance imaging (MRI). Thirty-three coronal brain slices of 11 individuals with neuropathologically confirmed dementia were subjected to a high-resolution postmortem 7T MRI protocol. First, we identified all visible small (⩽5 mm) intracortical and juxtacortical lesions on postmortem MRI. Lesions were classified as CMI or nonCMI based on histology, and their MR features were recorded. Thirty lesions were identified on the initial MRI evaluation, of which twenty-three could be matched with histology. Histopathology classified 12 lesions as CMIs, all of which were located intracortically. On the basis of their MR features, they could be classified as chronic gliotic CMIs—with or without cavitation or hemorrhagic components—and acute CMIs. Eleven MRI identified lesions were not of ischemic nature and most commonly enlarged or atypically shaped perivascular spaces. Their MRI features were similar to gliotic CMIs with or without cavitation, but these ‘CMI mimics'' were always located juxtacortically. 7T postmortem MRI distinguishes different histopathologic types of cortical CMIs, with distinctive MR characteristics. On the basis of our findings, we propose in vivo rating criteria for the detection of intracortical CMIs. 相似文献