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281.
Angiography of liver transplantation patients   总被引:9,自引:0,他引:9  
Over 45 months, 119 angiographic examinations were performed in 95 patients prior to liver transplantation, and 53 examinations in 44 patients after transplantation. Transplantation feasibility was influenced by patency of the portal vein and inferior vena cava. Selective arterial portography, wedged hepatic venography, and transhepatic portography were used to assess the portal vein if sonography or computed tomography was inconclusive. Major indications for angiography after transplantation included early liver failure, sepsis, unexplained elevation of liver enzyme levels, and delayed bile leakage, all of which may be due to hepatic artery thrombosis. Other indications included gastrointestinal tract bleeding, hemobilia, and evaluation of portal vein patency in patients with chronic rejection who were being considered for retransplantation. Normal radiographic features of hepatic artery and portal vein reconstruction are demonstrated. Complications diagnosed using results of angiography included hepatic artery or portal vein stenoses and thromboses and pancreaticoduodenal aneurysms. Intrahepatic arterial narrowing, attenuation, slow flow, and poor filling were seen in five patients with rejection.  相似文献   
282.
Abstract: Xenografts of organ cultured fetal pig pancreas in prediabetic NOD mice can survive for prolonged periods (>20 weeks) in recipients treated with anti-T cell monoclonal antibodies (MAb) directed against host CD4 and CD3 cell surface molecules. Anti-CD4 MAb treatment alone is only partly effective and xenograft rejection occurs over a period of many weeks. In diabetic recipients, by contrast, recurrence of autoimmune disease in isografts is rapid (<28 days) despite similar depletion of CD4+ve T cells. In spontaneously diabetic NOD mice immunosuppressed with anti-CD3 and anti-CD4 MAbs xenograft function occurs and the recipient's blood glucose levels fall into the pig range. Organ cultured fetal pig pancreas transplanted into cynomolgus monkeys is rapidly but not hyperacutely rejected when azathioprine-cyclosporin A-prednisolone immunosuppression is used. Anti-T-cell MAb treatment is now being studied in this primate model.  相似文献   
283.
This paper describes the histological picture of four tumours of the follicular compartment of the lymph node, in which the proliferating cell appeared to be the dendritic reticulum cell (DRC). This assumption was based on the results of light microscopical, ultrastructural, immunological, and enzymehistochemical investigations. The tumour cells resembled DRC's closely in (1) the striking pattern of interdigitations and occasional tight junction-like contacts between the neoplastic cells on electron microscopical analysis; (2) presence of receptors for the activated third component of complement on the membrane of the cells; (3) absence of monoclonal immunoglobulins and T-cell antigen on the surface and of lysozyme, alpha 1-antitrypsin or alpha 1-antichymotrypsin in the cytoplasm of the neoplastic cells. Moreover, (4) the tumour cells showed moderate alpha-naphtyl acetate esterase, weak to absent acid phosphatase and (with one exception) strong 5-nucleotidase activity. Furthermore, (5) the neoplastic cells expressed Ia-like antigens on the surface in all four cases. The relation with follicle centre cell lymphomas, the differential diagnosis and clinical data are discussed.  相似文献   
284.
The immunohistochemistry of the cell population of the human spleen was studied. As controls, a strictly defined group of five specimens were used. This study stresses the need for the utmost care in this selection procedure. Using enzyme- and immuno-histochemistry the lymphocyte subpopulations were studied as to their localization in the several specific compartments in the red and white pulp. The findings were compared to those in idiopathic thrombocytopenic purpura, autoimmune haemolytic anaemia and Hodgkin's disease. In the controls a consistent pattern was found. There were specific changes in each of the disease groups consisting mainly of shifts between the compartments.  相似文献   
285.
The blood of most patients with active multiple myeloma (MM) contains cells related to the bone marrow tumor. However, identifying clonal cells in the blood of patients with monoclonal gammopathy of undetermined significance (MGUS) has been difficult. In this study, we analyzed blood mononuclear cells (BMNCs) from 16 patients with MGUS, 2 with amyloidosis, 8 with smoldering MM (SMM), 2 with indolent MM (IMM), and 15 with active MM using three different methods to detect and quantitate clonal cells, ie, immunofluorescence microscopy (IM) for monoclonal plasma cells, three-color flow cytometry (FC) for CD38(+)CD45- CD45(dim) cells, and the allele-specific oligonucleotide polymerase chain reaction (ASO-PCR). Using ASO-PCR, we were able to detect clonal cells in the blood in 13 of 16 patients with MGUS, 2 of 2 with amyloid, 6 of 8 with SMM, 2 of 2 with IMM, and 13 of 15 with MM. In 9 of the 13 patients with MGUS with blood involvement, the number of clonal cells was very small ( < 0.04% of the BMNCs). The median percentage of clonal cells as determined by ASO-PCR was 0.02 for MGUS, 0.02 for SMM, and 0.24 for MM. Clonal plasma cells or CD38+CD45- CD45(dim) cells were identified by IM or FC in 6 of 16 MGUS patients, 4 of 8 with SMM, and 11 of 15 with MM. In all cases in which IM or FC detected clonal cells, the ASO-PCR was positive. This study shows that, by using ASO-PCR, clonal cells can be found at very low levels in the blood in most patients with MGUS. However, the number of clonal cells in the blood of MGUS patients is less than those with overt MM (P = .006). In contrast to MGUS, patients with active MM are more likely to have identifiable clonal circulating plasma cells (P = .05).  相似文献   
286.
287.
Atrophy and fatty infiltration are important causes of muscle weakness in inclusion body myositis (IBM). Muscle weakness can also be caused by reduced specific force; i.e. the amount of force generated per unit of residual muscle tissue. This study investigates in vivo specific force of the quadriceps and ex vivo specific force of single muscle fibers in patients with IBM. We included 8 participants with IBM and 12 healthy controls, who all underwent quantitative muscle testing, quantitative MRI of the quadriceps and paired muscle biopsies of the quadriceps and tibialis anterior. Single muscle fibers were isolated to measure muscle fiber specific force and contractile properties. Both in vivo quadriceps specific force and ex vivo muscle fiber specific force were reduced. Muscle fiber dysfunction was accompanied by reduced active stiffness, which reflects a decrease in the number of attached actin-myosin cross-bridges during activation. Myosin concentration was reduced in IBM fibers. Because reduced specific force contributes to muscle weakness in patients with IBM, therapeutic strategies that augment muscle fiber strength may provide benefit to patients with IBM.  相似文献   
288.
Methyl-methacrylate embedding makes it possible to obtain semi-thin sections rich in detail and without tissue shrinkage. The procedure requires considerable time and labour, and great care must be taken to prevent heat damage to the tissue during the exothermic polymerization process. The original method given by Burkhardt (1966) and later modifications are described and discussed, with special attention to the practical problems encountered and their solutions.  相似文献   
289.
The Src family of non-transmembrane protein kinases is comprised of eleven homologous members in mammals. Together, these kinases regulate a wide variety of cellular processes including cell survival, proliferation, differentiation, and motility. One member of this family, Lck, plays a pivotal role in T-cell signaling. Inhibition of Lck with small molecules has significant potential for therapeutic immunosuppression and treatment of diseases such as rheumatoid arthritis and asthma. Critical for successful clinical use of any Lck inhibitor is high specificity for Lck as inhibition of other members of the Src kinase family may result in unwanted side effects. In this review we provide an overview of the various synthetic compounds currently under investigation as Lck-specific inhibitors. In addition we provide an analysis of the properties of these compounds that account for the specificity required for the inhibition of one of eleven highly similar kinases.  相似文献   
290.
We describe 10 cases of sacral fractures diagnosed within the rheumatology department at Southend Hospital over the last 5 yr. All presented with sudden-onset low back pain. The majority were elderly, frail, with chronic inflammatory disease (six with rheumatoid arthritis, one with polymyalgia rheumatica, one with vasculitis) and had received steroids. Diagnosis was delayed by the inability of plain radiographs to show these fractures and was ultimately demonstrated by technetium scintigraphy/computed tomography scan. We feel that this diagnosis should be considered in elderly patients with rheumatoid arthritis or other risk factors for osteoporosis who present with low back pain and sacral tenderness. Further clues may be parasymphyseal tenderness (suggesting associated pubic ramus fracture), elevated alkaline phosphatase and plain radiograph showing pubic ramus fractures or parasymphyseal sclerosis. Patients with this complication generally have a poor prognosis and two of our patients have died. Seven required in-patient stay (mean 20 days; range 14-41). The mortality, morbidity and costs incurred in management may be comparable to those of femoral neck fractures.   相似文献   
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