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As part of our current efforts to develop assays and reagents to study the immune system of marine mammals, and in view of the effort currently made to develop monoclonal antibodies to cell surface proteins of lymphocyte subsets in different species, the present paper reports on the characterization of a monoclonal antibody against the homologue of CD45R on cetacean lymphocytes. The specificity of this antibody has been characterized on the basis of immunoprecipitation of the antigen it recognized, immunoperoxidase staining on cetacean lymph node and thymus sections, as well as one and two-colour flow cytometric analysis of cetacean peripheral blood mononuclear cells and single-cell suspensions of thymus, lymph node and spleen. Anticetacean CD45R (F21.H) immunoprecipitated proteins of 180, 200 and 220 x 10(3) MW, with the 180 x 10(3) MW from being predominantly expressed on T cells and the 220 x 10(3) MW form expressed predominantly on B cells and thymocytes F21.H labelled all B cells and a proportion of T cells on single-cell suspensions of spleen cells. CD45R- killer whale peripheral blood lymphocytes expressed a higher density of CD2 than CD45R+, a characteristic of memory T cells. Killer whale T lymphocytes also lost the expression of CD45R upon activation with concanavalin A (Con A) and phytohaemagglutinin (PHA). This is the first report of a monoclonal antibody to CD45R in cetaceans, and this antibody is foreseen as a possible valuable diagnostic and research tool to assess immune functions of captive and wild cetaceans as part of the evaluation of their health status.  相似文献   
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GOAL: Evaluate the relations between the clinical Cobb angle measured on radiographic images and the computerized Cobb angles measured on curves passing through: 1) the vertebral body centroids, 2) the pedicle centroids and 3) the spinous process tips, in the frontal plane, the sagittal plane and the plane of maximum curvature. MATERIAL AND METHODS: A bi-planar radiographic technique was used to reconstruct in 3D the spine geometry for 39 adolescent girls having double-curved idiopathic scoliosis. The Cobb angles were measured clinically on the radiographs and were computed on the 3 curves. RESULTS: Every relation was found significant and their determination coefficient (R2) was between 0.38 and 0.98. Linear relations were established between clinical and computerized angles. Angles measured on the curve passing through the pedicle centroid correlated best with clinical indices. CONCLUSIONS: The computerized measurements of Cobb angles from 3D models can be used with confidence and are interchangeable, provided the appropriate conversion factor is used.  相似文献   
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Objective: This study was undertaken to evaluate the changes in total and anti-herpes simplex virus (HSV)-specific cervical IgA and IgG antibody profiles during and after pregnancy.Methods: Serum and cervical secretions were obtained from pregnant patients before 20 weeks gestation, at 34-36 weeks gestation, and at 6 weeks postpartum and tested for total IgA and IgG antibody and for IgA and IgG to HSV proteins by Western blot.Results: Seven women were HSV seronegative, 14 HSV-1 seropositive, and 14 HSV-2 +/- HSV-1 seropositive. Minimal changes in the serum anti-HSV profiles were seen over the 3 visits. The total cervical IgA, IgG, and protein levels did not change between the 2 pregnancy visits but tended to increase at the postpartum visit. No consistent change in cervical HSV-specific IgA and IgG was seen during pregnancy, but the levels increased markedly at the postpartum visit.Conclusions: Lower cervical anti-HSV antibody levels may be related to the previously reported increased frequency of a reactivation of HSV during late pregnancy. Further evaluation is necessary to confirm and quantify the changes in genital immunity during pregnancy and to evaluate whether the increased levels at the postpartum visit are sustained.  相似文献   
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Background contextVariability in classifying and selecting levels of fusion in adolescent idiopathic scoliosis (AIS) has been repeatedly documented. Several computer algorithms have been used to classify AIS based on the geometrical features, but none have attempted to analyze its treatment patterns.PurposeTo use self-organizing maps (SOM), a kind of artificial neural networks, to reliably classify AIS cases from a large database. To analyze surgeon's treatment pattern in selecting curve regions to fuse in AIS using Lenke classification and SOM.Study designThis is a technical concept article on the possibility and benefits of using neural networks to classify AIS and a retrospective analysis of AIS curve regions selected for fusion.Patient sampleA total of 1,776 patients surgically treated for AIS were prospectively enrolled in a multicentric database. Cobb angles were measured on AIS patient spine radiographies, and patients were classified according to Lenke classification.Outcome measuresFor each patient in the database, surgical approach and levels of fusion selected by the treating surgeon were recorded.MethodsA Kohonen SOM was generated using 1,776 surgically treated AIS cases. The quality of the SOM was tested using topological error. Percentages of prediction of fusion based on Lenke classification for each patient in the database and for each node in the SOM were calculated. Lenke curve types, treatment pattern, and kappa statistics for agreement between fusion realized and fusion recommended by Lenke classification were plotted on each node of the map.ResultsThe topographic error for the SOM generated was 0.02, which demonstrates high accuracy. The SOM differentiates clear clusters of curve type nodes on the map. The SOM also shows epicenters for main thoracic, double thoracic, and thoracolumbar/lumbar curve types and transition zones between clusters. When cases are taken individually, Lenke classification predicted curve regions fused by the surgeon in 46% of cases. When those cases are reorganized by the SOM into nodes, Lenke classification predicted the curve regions to fuse in 82% of the nodes. Agreement with Lenke classification principles was high in epicenters for curve types 1, 2, and 5, moderate in cluster for curve types 3, 4, and 6, and low in transition zones between curve types.ConclusionsAn AIS SOM with high accuracy was successfully generated. Lenke classification principles are followed in 46% of the cases but in 82% of the nodes on the SOM. The SOM highlights the tendency of surgeons to follow Lenke classification principles for similar curves on the SOM. Self-organizing map classification of AIS could be valuable to surgeons because it bypasses the limitations imposed by rigid classification such as cutoff values on Cobb angle to define curve types. It can extract similar cases from large databases to analyze and guide treatment.  相似文献   
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Healthy 4-6 y old children from Italy and Sweden immunized with DTPa and inactivated or oral polio vaccines at 3, 5 and 11-12 months of age, received 1 dose of combined DTPa-IPV (n = 211) or DTPa + IPV as separate doses (n = 205) in a randomized trial. The pre-booster seroprotection rates were similar in each group and were above 60% against all antigens except diphtheria (31.3% and 37.0%) and PT (21.5% and 25.9%) in the DTPa-IPV and DTPa + IPV groups, respectively. At least 99.5% of subjects had seroprotective antibody levels against diphtheria, tetanus and polioviruses and > or = 96% showed a vaccine response to each pertussis antigen after vaccination. Post-booster antibody levels increased at least 51-fold for anti-diphtheria and anti-tetanus, at least 18-fold for anti-pertussis antibodies and at least 32-fold for antibodies against all 3 poliovirus types, compared to prior levels. DTPa-IPV was comparable to DTPa + IPV in terms of seroprotection rates and mean antibody levels against each vaccine antigen. Similar reactogenicity profiles were observed between groups including swelling > 50 mm [13% (9.1, 18.7) vs 17% (12.4, 23.4)] or involving an adjacent joint [0% (-,-) vs 1.5% (0.3, 4.3)] and were consistent with previous reports. The combined DTPa-IPV vaccine could be used to add DTP valences to the IPV vaccine currently given to children in Scandinavia and Italy at 4-6 y of age and reinforce protection against 4 diseases.  相似文献   
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