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991.
Expression of MHC products by normal and abnormal bile duct epithelium   总被引:2,自引:0,他引:2  
Using antibodies directed to beta 2-microglobulin (b2-m) and HLADR antigens, the expression of MHC products by normal and abnormal bile ducts in 90 paraffin-embedded biopsies showing various liver diseases, was studied. Normal and abnormal bile ducts constantly expressed b2-m. Increased b2-m expression was found in 17/19 PBC, and 4/7 chronic aggressive hepatitis or cirrhosis of viral etiology with hepatitic bile duct lesions. Normal bile ducts failed to express HLADR antigens. Aberrant HLADR display was found in 24/26 PBC and 10/16 chronic aggressive hepatitis or cirrhosis of viral etiology with hepatitic bile duct lesions. It is concluded that the pattern of the major histocompatibility complex (MHC) display does not discriminate between PBC and hepatitic bile duct lesions. Enhanced expression of class I MHC products at the surface of medium-sized bile ducts in PBC may render these structures more susceptible to lysis by cytotoxic T-cells, whereas its significance in chronic aggressive hepatitis or cirrhosis remains unknown. Aberrant expression of HLADR antigens by abnormal bile ducts in PBC and chronic aggressive hepatitis or cirrhosis of viral etiology is probably induced by gamma-interferon, liberated by intra-epithelial lymphocytes, and may serve to enhance the immune response, either by attracting HLADR-restricted cytotoxic T-cells or by the presentation of non-self antigens at the surface of bile duct epithelium.  相似文献   
992.

Background  

Statin-related skeletal muscle disorders range from benign myalgias – such as non-specific muscle aches or joint pains without elevated serum creatinine kinase (CK) concentration – to true myositis with >10-fold elevation of serum CK, to rhabdomyolysis and myoglobinuria. The genetic basis of statin-related muscle disorders is largely unknown. Because mutations in the COQ2 gene are associated with severe inherited myopathy, we hypothesized that common, mild genetic variation in COQ2 would be associated with inter-individual variation in statin intolerance. We studied 133 subjects who developed myopathy on statin monotherapy and 158 matched controls who tolerated statins without incident or complaint.  相似文献   
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Existing knowledge and present experience relating to the indications for imaging techniques in trauma surgery were summarised, screened and considered in different ways by representatives of various professional scientific bodies, with the aim of finding what procedures should be implemented as the primary examination techniques after a careful clinical examination when particular posttraumatic situations affecting the knee, foot, ankle, or hand were found. In the course of an interdisciplinary consensus conference the evidence-based recommendations prepared by a panel were discussed and modified, giving rise to statements on the suitability of the given imaging techniques in 28 different clinical situations immediately after a clinical examination, based on scientific evidence and medical consensus. The degree of consensus was measured and carefully documented. These statements were transformed into decision algorithms and presented to doctors working in accident and emergency medicine during a conference on trauma surgery, with the aim of.measuring the acceptance of the statements among those attending the trauma surgery meeting. The remarks made by the participants during the discussion and the results of the acceptance measurements clearly show the need for further discussion among experts.  相似文献   
996.
The application of anti-neutrophil cytoplasmic antibody (ANCA)testing has received much interest since ANCA were discovered[1] and since they were reported to be useful in both the diagnosisand monitoring of disease activity in Wegener's granulomatosis(WG) [2]. Although there is little doubt that the recognitionof the association between the presence of ANCA and active vasculitishas had a very positive influence on research on the pathogenesisand treatment of ANCA-associated diseases (reviewed by Savage[3]), there are reasons to worry about the application of thisrecently gained knowledge in clinical practice. In this commentthe problems with the clinical application of ANCA tests arecategorized for the sake of clarity as (i) standardization problems,(ii) difficulties with application of the test in the appropriate  相似文献   
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Current activities in the case management of patients with post-traumatic stress disorders are reported. In 2002 a project was initiated by accident insurance associations. The aim is to detect accident victims with stress disorder at an early stage and to avoid medical mismanagement.  相似文献   
1000.
There is some controversy over the treatment of acromioclavicular injuries. The use of the Rockwood classification as the basis for decisions on whether operative or nonoperative treatment is indicated is discussed critically, and the authors' preferred operative technique is described and illustrated by examples. We treat injuries classified according to the Rockwood classification as types I and II with conservative methods. In type III injuries the patient's age, job and free time activities determine whether or not surgery is indicated. In the case of type IV or type VI injuries we always perform temporary internal fixation of the acromioclavicular joint, using transarticular K-wire fixation or hookplate osteosynthesis. Satisfactory results of both operative and nonoperative treatment are reported in the literature. The authors' own results are presented.  相似文献   
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