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Apoptosis is a central physiological mechanism for maintaining cellular stability in tissue. Synovial fibroblasts, which play a central role in the pathogenesis of rheumatoid arthritis (RA), show a resistance to apoptosis. Several molecular mechanisms are involved in such resistance. Thus, soluble Fas can bind Fas ligands (Fas-L) and hinder Fas-L induced apoptosis in fibroblasts. SUMO-1 (a small ubiquitin-like modifier) attaches to proteins post-translationally. This appears to be significantly involved in apoptosis resistance in RA fibroblasts. SUMO-1 levels are substantially increased in synovial fibroblasts from RA patients. A change in the post-translational SUMOlation pattern could represent a new target for changing the stable activation of synovial fibroblasts in RA.  相似文献   
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Meningitis     
The most frequent pathogens causing bacterial meningitis in Germany are Neisseria meningitidis, Streptococcus pneumoniae, Borrelia burgdorferi, Listeria monocytogenes and staphylococci. Since immunization against Haemophilus influenzae has become a routine vaccination procedure, this pathogen no longer plays a significant role in the etiology of bacterial meningitis. A number of pilot studies have indicated that selected PCR methods most probably represent the future etiological diagnosis of bacterial meningitis. The easiest and most rapid diagnostic method is, however, still a simple gram stain preparation. In fatal cases that ran a peracute course, especially in the Waterhouse-Friderichsen syndrome, only increased congestion of the surface of the brain is detectable at autopsy. In such cases, there is hardly any histological evidence of an inflammatory reaction of the leptomeninges. In cases of purulent meningitis, in addition to the typical infiltration of the subarachnoid space with abundant granulocytes, after some days of illness there is a wide-spread histomorphological picture of pathological alterations with fibrinoid vessel wall necroses, thromboses, ventriculitis, infarctions as well as venous and arterial vasculitis. The breakdown of the integrity of the blood-brain-barrier in bacterial meningitis is obviously due to a separation of intercellular tight junctions of the endothelium of the capillaries of the leptomeninges. The cause of death in meningitis, depending on the severity and duration of a concomitant sepsis, is an increase in intracranial pressure that leads to a circulus vitiosus (via a reduced central perfusion associated with metabolic acidosis) with cerebral vasodilatation. This is followed by an additional rise of intracranial pressure and finally a reduced cerebral blood supply and central dysregulation. The medico-legal expert is occasionally confronted with this topic against the background of a possible misjudgement of the disease due to insufficient diagnostics or delayed diagnosis and in the light of a posttraumatic or nosocomial origin of the illness.  相似文献   
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PURPOSE: To compare tests for intestinal function with clinical scores after abdominal irradiation. PATIENTS AND METHODS: At the Department of Radiotherapy, Erfurt, Germany, intestinal changes were studied in 91 patients receiving abdominal radiotherapy between 1992 and 1996. Conventional fractionation (1.8-2 Gy per fraction, total doses 30.6-62.5 Gy) was applied. Before and at weekly intervals during radiotherapy, the clinical response was scored according to RTOG/EORTC for the upper and lower gastrointestinal (GI) tract. Resorption tests for vitamin B(12) and D-xylose were performed before the onset and immediately after treatment. RESULTS: The clinical response displayed a well-defined dose-effect relationship with grade 1 effects in 5% and 50% of the patients at about 10 Gy and 50 Gy, respectively. For grade 2 reactions, 5%- and 50%-effective doses were 20-30 Gy and 60-80 Gy. Effects in the upper and lower GI tract were highly correlated. Changes in body weight did not show a correlation with other clinical symptoms. Changes in resorption also displayed a significant dose effect. However, no correlation was found with the clinical symptoms in the individual patient. CONCLUSION: In the present study, the clinical manifestation of intestinal side effects according to RTOG/EORTC criteria was reflected by neither the vitamin B(12) nor by the D-xylose resorption test. Hence, these tests cannot be regarded as useful for objective quantitation of intestinal radiation injury.  相似文献   
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Maximum anchorage often presents a problem that is difficult to solve during orthodontic tooth movement. Stationary, skeletal anchorage can be achieved in a simple, minimally-invasive manner, and unwanted tooth movements in opposite directions can be prevented by using transmucosally-inserted bone screws.Our initial experience using the FAMI screw as an orthodontic micro-implant proved to be clinically and histologically successful.  相似文献   
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The study presented here was conducted to evaluate the performance of the newly available RIDASCREEN Set (R-Biopharm AG, Darmstadt, Germany) for the detection of immunoglobulin G antibodies against Entamoeba histolytica. The sensitivity and specificity of this new enzyme-linked immunosorbent assay were evaluated using a panel of sera from 239 individuals. The assay was positive for 43 of 44 patients with invasive amebiasis, including all 18 patients with amebic liver abscess, while it was negative for 190 of 195 adult controls who were either healthy individuals or patients with other parasitic diseases. The kit was found to be highly specific (97.4%) and sensitive (97.7%) for detecting antibodies against E. histolytica in humans. Although antibody titers in patients with amebic liver abscess tend to be higher on average than in patients with invasive amebiasis, it is not possible to distinguish the two forms solely based on the results of this commercial test.  相似文献   
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