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During the treatment of patients with renal failure or renal transplants the most important consideration is to eliminate sources of infection before and after the treatment. Acute or chronic oral infections or bacteraemias resulting from dental procedures may cause serious complications in these patients who already have lowered host resistance caused by immunosuppressant therapy. In order to determine the latest concepts from some international transplantation centres relating to the importance of and the effect of infective sources in the oral cavity, a survey form was prepared which included several questions related to oral foci of infection and renal transplantations.
Results obtained from 22 centres from 12 countries indicated that the majority of the centres included a dental examination in their routine protocol and required completion of any necessary dental treatment before transplantation. However, full agreement among all these centres on the necessity for dental examination as part of the protocol has not yet been reached.  相似文献   
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Brain tissues from 6 patients with concentric sclerosis (Baló) were examined by in situ hybridization, immunocytochemistry, morphometry, and histological methods. The patients were 24 to 48 years old and had progressive cerebral symptoms and signs that lasted 15 to 100 days. Large demyelinative lesions, most frequent in the frontal white matter, contained alternating bands of demyelinated and partly myelinated white matter that were arranged in concentric or mosaic patterns. In the areas of demyelination, axons were relatively well preserved and there were perivascular inflammatory infiltrates. In 2 specimens, lesions contained regions with the characteristic appearance of actively demyelinating multiple sclerosis plaques. Oligodendroglial densities were highest in normal-appearing white matter, lower in partially myelinated areas, and lowest in demyelinated areas, which also contained many hypertrophic astrocytes closely associated with oligodendroglia. Messenger RNA levels for myelin-related proteins followed the same pattern; they were lowest in demyelinated areas, higher in partially myelinated areas, and highest in normal-appearing white matter beyond lesion margins. Our findings suggest that concentric sclerosis is a variant of multiple sclerosis, that oligodendroglial loss is important in the pathogenesis of demyelination, and that partially myelinated areas probably represent stages of ongoing myelin breakdown rather than remyelination of previously demyelinated areas.  相似文献   
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O6-Methylguanine methyltransferase (O6-MT) was measured and compared in extracts of 7 human fetal tissues obtained from 21 different fetal specimens as a function of fetal age and race and of maternal smoking and drug usage. Liver exhibited the highest activity followed by kidney, lung, small intestine, large intestine, skin, and brain. Each fetal organ homogenate exhibited a 3- to 5-fold level of interindividual variation of O6-MT. There did not appear to be any significant differences of O6-MT as a function of fetal race and age and in the tissues obtained from mothers who smoked cigarettes during pregnancy. The fetal tissues obtained from an individual using phenobarbital exhibited 4-fold increases in O6-MT activity. The tissues obtained from another individual on kidney dialysis were 2- to 3-fold higher than the normal population. These data suggest a possible enhancement of human fetal O6-MT by certain xenobiotics, with little if any modulation by racial factors and maternal smoking habits.  相似文献   
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