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81.
Helin H Lundin M Lundin J Martikainen P Tammela T Helin H van der Kwast T Isola J 《Human pathology》2005,36(4):381-386
Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading. 相似文献
82.
83.
Larsen TB Nielsen JN Fredholm L Lund ED Brandslund I Munkholm P Hey H 《Pathophysiology of haemostasis and thrombosis》2002,32(2):92-96
Patients with inflammatory bowel disease (IBD) are susceptible to thromboembolic complications. Several mechanisms can be responsible, including abnormal regulation of coagulation activity, disturbances of fibrinolysis, inflammatory reactions and thrombocytosis. The aim of this study was to assess hemostatic alterations in these parameters during exacerbation of disease. We studied disease activity in 99 IBD patients receiving anti-inflammatory therapy, in relation to: procoagulant markers, i.e. prothrombin fragment F1 + 2 (F1 + 2), D-dimer and platelet count, anticoagulant markers, i.e. protein C, protein S and antithrombin, and a mediator of inflammation (IL-6). Coagulation activity and platelet count were increased during active disease in IBD patients compared with those in a state of remission. The IL-6 concentrations were positively correlated with disease activity and thrombocytosis in patients with ulcerative colitis, but no association with the anticoagulant capacity could be demonstrated except for a decrease in protein C during high disease activity. 相似文献
84.
W R Hein S J McClure M Miyasaka 《International archives of allergy and applied immunology》1987,84(3):241-246
The surface phenotype of cells in peripheral lymph collected from afferent lymphatics leading to the popliteal lymph node of sheep was determined using a panel of monoclonal antibodies (mAbs). The majority of lymphocytes (83.5%) expressed the sheep pan-T cell antigen and only 13.3% bore surface immunoglobulin molecules. All peripheral T cell subsets occurring in sheep were detected; 50.2% of lymphocytes were positive for mAb SBU-T4 (T helper), 7.3% were positive for mAb ST-8 (T cytotoxic), and 8.4 and 43.0% expressed T subset markers recognized by mAbs 197 and T-80, respectively. Major histocompatibility complex (MHC) class I antigens were detected on 71.1% of lymphocytes and MHC class II antigens on 21.8%. The macrophage/veiled cells found in peripheral lymph did not express lymphocyte subset markers but were positive for MHC class I and II antigens, the sheep homologue of T6 antigen, leukocyte common antigen and mAb 175 (myeloid/erythroid). Macrophage-like cells occurring in the epidermis of skin taken from the lower hindleg gave positive staining reactions to the same mAbs which stained the macrophage/veiled cells in peripheral lymph. These results illustrate differences between the migration of lymphocyte subsets through nonlymphoid as compared to lymphoid tissues and point to a possible developmental or migratory relationship between the macrophage-like cells in skin and those in afferent popliteal lymph. 相似文献
85.
T. Neumann P. Oelzner P. K. Petrow K. Thoss G. Hein G. Stein R. Bräuer 《Inflammation research》2006,55(1):32-39
Objective: To assess the effect of osteoprotegerin (OPG) on joint swelling, synovial inflammation and cartilage destruction, periarticular
and axial bone volume, and bone turnover in rat antigen-induced arthritis (AIA). Design: Rats were treated with OPG (3 mg/kg/day) at regular intervals from day 1 to day 20 of AIA. Disease activity was evaluated
by measurement of joint swelling as well as, joint inflammation and destruction by histology. Bone volume and cellular turnover
parameters of secondary spongiosa of the right tibia head and the third lumbar vertebra were evaluated by histomorphometry.
Periarticular bone volume of the primary spongiosa at the right tibia head was measured by linear scanning. The findings were
compared with those of PBS-treated AIA and healthy animals. Result: OPG treatment did not reduce joint swelling or histological signs of inflammation. Cartilage destruction was reduced. However,
this effect did not reach statistical significance . In the secondary spongiosa OPG treatment reduced the loss of periarticular
bone volume. However, the latter did not reach the level of healthy controls. OPG treatment significantly reduced parameters
of bone formation and bone resorption. In the primary spongiosa, OPG-treatment led to a higher amount of mineralized tissue
and a greater number of trabeculae compared to PBS-treated animals with AIA or healthy controls. In the axial skeleton, OPG
treatment reduced bone formation and bone resorption parameters compared to healthy animals. This treatment had no influence
on bone volume. Conclusions: In periarticular bone of AIA rats, OPG treatment reduced the loss of bone volume and decreased the bone turnover, thus preventing
periarticular bone destruction. OPG treatment had no influence on inflammatory process or on cartilage destruction.
Received 2 June 2005; returned for revision 26 July 2005; returned for final revision 9 August 2005; accepted by M. Parnham
24 September 2005
Presented in part at the 66. Annual Meeting of the American College of Rheumatology, New Orleans, U.S.A., October 2002, and
at the 25. Annual Meeting of the American Society of Bone and Mineral Research, Minneapolis, USA, September 2003
Supported by grants from the Thuringian Ministry of Science, Research and Art (B307-01025, B378-01017), the Interdisciplinary
Center for Clinical Research (IZKF) Jena, and the Deutsche Forschungsgemeinschaft (Br 1372/5-1)
Osteoprotegerin was generously provided by Amgen (Thousand Oaks, CA, USA).
Drs. Neumann and Oelzner contributed equally to this work. 相似文献
86.
IgE Anti-IgG Antibodies in Patients with Juvenile and Adult Rheumatoid Arthritis Including Felty's Syndrome 总被引:1,自引:0,他引:1
Anti-IgG; antihodies (anti-IgG) of the IgE class were studied in sera from patients with juvenile rheumatoid arthritis (JRA). rheumatoid arthritis (RA) and patients with Felty's syndrome (FS) by use of an indirect immunofluorescence technique. Forty-two percent of 26 patients with JRA had IgE anti-IgG in serum all in low titers. Positive reactions prevailed in patients with multiple joint involvement. Sixty-three percent of 30 patients with RA and 80% of 20 patients with FS had IgE anti-IgG, the titers found in FS patients being significantly higher. In JRA and FS patients the IgE anti-IgG titers were correlated to the titers of anti-IgG of the IgG class, and for FS patients also with the IgM and IgA classes of anti-IgG. In six of 10 patients with RA the synovial fluid samples from both knees contained IgE anti-IgG. In four of these patients the titers of IgE anti-IgG were higher than in the corresponding serum sample, pointing to a local production. After G-200 Sephadex chromatography IgE anti-IgG were demonstrated in the void volume indicating the presence of these autoantibodies in immune complexes. IgE anti-IgG may be involved in the pathogenesis of JRA and RA by eliciting Type I and III reactions. 相似文献
87.
Joachim Böttcher M.D. Alexander Pfeil Anders Rosholm Ph.D. Max-Ludwig Schäfer Ansgar Malich M.D. Alexander Petrovitch M.D. Bettina Seidl Gabriele Lehmann M.D. Hans-Joachim Mentzel M.D. Gert Hein M.D. Gunter Wolf M.D. Werner A. Kaiser M.D. M.S. 《Journal of digital imaging》2006,19(3):279-288
Purpose Our study evaluates digital x-ray radiogrammetry (DXR) and Radiogrammetry Kit (RK) as a new diagnostic method for the measurement
of disease-related osteoporosis including quantification of joint space narrowing dependent on the severity of rheumatoid
arthritis (RA).
Materials and Methods A total of 172 unselected patients with RA underwent computerized measurements of bone mineral density (BMD) and metacarpal
index (MCI) by DXR, as well as a semiautomated measurement of joint space distances at the metacarpal–phalangeal articulation
(JSD-MCP 2–5), both were analyzed from plain radiographs of the nondominant hand.
Results Correlations between DXR-BMD and DXR-MCI vs. parameters of RK were all significant (0.34 < R < 0.61; p < 0.01). An expected negative association was observed between RK parameters and the different scoring methods (−0.27 < R < −0.59). The maximum relative decrease in BMD vs. MCI as measured by DXR between the highest and lowest RA severity group
was −27.7% vs. −27.5% (p < 0.01) for the modified Larsen Score, whereas the minimal value of relative DXR-BMD and DXR-MCI reduction could be documented
for the Sharp Erosion Score (−20.8% vs. −26.8%; p < 0.01). The relative reduction of mean JSD-MCP using RK significantly varied from −25.0% (Sharp Erosion Score) to −41.2%
(modified Larsen Score). In addition, an excellent reproducibility of DXR and RK could be verified.
Conclusion DXR in combination with RK could be a promising, widely available diagnostic tool to supplement the different scoring methods
of RA with quantitative data, allowing an earlier and improved diagnosis and more precision in determining disease progression. 相似文献
88.
89.
Fluorescence in situ hybridization with peptide nucleic acid probes for rapid identification of Candida albicans directly from blood culture bottles 下载免费PDF全文
Rigby S Procop GW Haase G Wilson D Hall G Kurtzman C Oliveira K Von Oy S Hyldig-Nielsen JJ Coull J Stender H 《Journal of clinical microbiology》2002,40(6):2182-2186
A new fluorescence in situ hybridization (FISH) method that uses peptide nucleic acid (PNA) probes for identification of Candida albicans directly from positive-blood-culture bottles in which yeast was observed by Gram staining (herein referred to as yeast-positive blood culture bottles) is described. The test (the C. albicans PNA FISH method) is based on a fluorescein-labeled PNA probe that targets C. albicans 26S rRNA. The PNA probe is added to smears made directly from the contents of the blood culture bottle and hybridized for 90 min at 55 degrees C. Unhybridized PNA probe is removed by washing of the mixture (30 min), and the smears are examined by fluorescence microscopy. The specificity of the method was confirmed with 23 reference strains representing phylogenetically related yeast species and 148 clinical isolates covering the clinically most significant yeast species, including C. albicans (n = 72), C. dubliniensis (n = 58), C. glabrata (n = 5), C. krusei (n = 2), C. parapsilosis (n = 4), and C. tropicalis (n = 3). The performance of the C. albicans PNA FISH method as a diagnostic test was evaluated with 33 routine and 25 simulated yeast-positive blood culture bottles and showed 100% sensitivity and 100% specificity. It is concluded that this 2.5-h method for the definitive identification of C. albicans directly from yeast-positive blood culture bottles provides important information for optimal antifungal therapy and patient management. 相似文献
90.