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Considerable genetic evidence exit for ANCA-associated vasculitis and pathogenesis. HLA A and B alleles identified serologically from 84 ANCA-positive patients were compared with 101 controls. Further subtyping were done in the 27 "pauci-immune" vasculitis patients using the polymerase chain reaction based PCR-SSOP technique and compared with controls (67). The results revealed that HLA A1 (OR=4.00; p value 2.72E-05), B17 (OR=3.38; p value 0.0008) and HLA B40 (OR=2.74; p value 0.001) were significantly increased among ANCA-positive patients when compared with the controls. Further, the molecular subtypes A*0101 (OR=5.04; p value 0.0005), B*5801 (OR=4.47; p value 0.0002) and haplotype A*0101-B*5801 (OR=4.47; p value 0.0001) were significantly increased among the autoimmune patients. The study revealed that HLA A1, B17 and B40 alleles are associated in production of antineutrophil autoantibodies and A*0101-B*5801 haplotype is significantly associated with autoimmune diseases and they may be invariably involved in disease pathogenesis in India.  相似文献   
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Summary Between 1978 and 1983 a total of 33 patients with non-Hodgkin's lymphoma (NHL) involving the gastrointestinal tract were seen in our institution. Pathological classification was performed according to Kiel. Low grade NHL was diagnosed in 17, high grade NHL in 16 patients. The most frequent histological entity was lymphoplasmocytoid immunocytoma (11 patients). The most common sites of origin were the stomach (23 patients) and the ileocecal region (6 patients). The majority of patients presented with stage I and II disease (20 of 33 patients). As a rule primary therapy consisted of surgery with curative intent. Most of the patients received additional chemotherapy or radiotherapy. Patients with limited disease and complete tumour resection showed long-term survival from 12+ to 57+ months (mean 32.9+ months). Patients with advanced disease (stage III and IV) and only palliative surgery or with lymphoblastic lymphoma had a probability of survival of less than 12 months.Abbreviations NHL non-Hodgkin's lymphoma - IC lymphoplasmocytoid immunocytoma - CC centrocytic lymphoma - CB/CC centroblastic/centrocytic lymphoma - CB centroblastic lymphoma - IB immunoblastic lymphoma - LB lymphoblastic lymphoma - NWDL nodular well-differentiated lymphocytic lymphoma - NPDL nodular poorly differentiated lymphocytic lymphoma - NM nodular mixed lymphoma - NH nodular histiocytic lymphoma - DWDL diffuse well-differentiated lymphocytic lymphoma - DPDL diffuse poorly differentiated lymphocytic lymphoma - DM diffuse mixed lymphoma - DH diffuse histiocytic lymphoma - DU diffuse undifferentiated lymphoma - CT computerized tomography - GI gastrointestinal  相似文献   
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Alginate-based microencapsulation is a promising method for long-term maintenance of cellular and membrane function of the cells and tissue fragments required for in vitro and in vivo biosensors, for tissue engineering and particularly for immunoisolation of non-autologous transplants. Microcapsules of high mechanical strength and optimum permeability can be produced by injection of BaCl2 crystals into alginate droplets before they come into contact with external Ba2+. A key requirement is that the system parameters (number of crystals, speed of the crystal stream etc.) are properly adjusted according to the mannuronic and guluronic acid ratio and the average molecular mass of the alginate as well as to the diameter of the microcapsules. Robust, reliable, rapid and low-cost validation tools are, therefore, needed for assurance of the microcapsule quality. Here, we describe a novel three-dimensional (3-D) dark-field microscopy that allows the real-time measurement of the number and spatial distribution of the injected Ba2+ ions throughout the microcapsules after treatment with sulphate. This novel method requires only a conventional microscope equipped with three polarising filters and a double aperture stop. In contrast to confocal laser scanning microscopy images, peripherally attached BaSO4 precipitates can clearly be distinguished from internal ones. The data also demonstrate that several steps of the alginate gelling process must be improved before such immunoisolation can be used in patients.  相似文献   
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A study was performed to investigate the effectiveness of hydroxyapatite cement (HAC) as a new carrier system in the treatment of chronic, posttraumatic osteomyelitis. In the in vitro study, release of gentamicin from standard cylinders of HAC were measured by agar diffusion test. As a representative for mechanical properties, compression strength was measured in order to detect changes when mixing HAC with gentamicin. In the in vivo study, bone infection was induced according to the model of Norden by injection of 1 ml Na-morrhuat and 3 x 10(6)CFU Staphylococcus aureus. After 3 weeks, when chronic stage of infection was obtained, 17 animals were treated by debridement and filling the marrow either with HAC alone or HAC mixed with gentamicin (32 mg/g). Animals of the control groups were left untreated. After 6 weeks, all animals were sacrificed. Hematological, radiological, microbiological and histological examinations were carried out by covered investigation. Best evidence of the efficiency of treatment was observed in histopathological and microbiological findings. In all swabs of the control groups, taken 6 weeks following infection S. aureus were detected which were clonal to the strain used for induction of osteomyelitis. In HAC/gentamicin-treated animals, no growth was detectable after 7 days of culturing in BHI bouillon. In the HAC/gentamicin-treated group, there was no histopathological evidence of infection. In all other groups different stages of chronic osteomyelitis were found. No side effect was observed, neither locally nor systemically by HAC or gentamicin. Therefore, HAC is considered to be a very effective carrier for antibiotics in treatment of chronic, posttraumatic osteomyelitis.  相似文献   
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