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We have prospectively studied the occurrence of monoclonal serum immunoglobulins in 38 recipients of BMT. Patients were young children with primary immunodeficiencies (n = 31), other inherited diseases (n = 4), leukemia (n = 2), or aplastic anemia (n = 1). Twenty-nine received an HLA-nonidentical marrow and nine an HLA-identical marrow. Serum monoclonal immunoglobulins were detected by the immunofixation method. Monoclonal immunoglobulins were found in 26 patients. Monoclonal components were more frequently detected in patients with primary severe T cell deficiencies (21/25) rather than in the other patients (6/13). In 7 of 29 recipients of HLA-nonidentical transplants, versus 0 out of 9 recipients of HLA-identical transplants, serum monoclonal immunoglobulins were found associated with a B lymphocyte proliferation syndrome due to an Epstein-Barr virus infection. In this group, monoclonal immunoglobulins were detected early, prior to the onset of the clinical syndrome. The simultaneous occurrence of several monoclonal immunoglobulins was more frequent in these patients, while monoclonal immunoglobulin concentrations increased faster, especially those of IgM isotype. These characteristics may allow in patients at risk (recipients with primary T cell immunodeficiencies and receiving HLA-nonidentical transplantation) an earlier diagnosis of B lymphocyte proliferative syndrome that may eventually lead to early and more efficient therapy.  相似文献   
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Background: Medullary thyroid carcinoma (MTC) can — even in recurrent cases — only be treated surgically. Therefore, preoperative localization of the tumor is essential.Methods: From April 1986 through April 1997, 137 patients with MTC were operated on at our clinic. In 22 patients with recurrent tumor which had not been radiologically localized, 28 selective venous catheterizations (SVC) with determination of calcitonin levels were carried out.Results: In 23 examinations a suspected tumor could be identified (nine cervical unilateral, seven mediastinal, four cervical unilateral and mediastinal, one cervical bilateral and mediastinal, one liver, one cervical unilateral and liver). In 18 cases surgery was performed for recurrence (nine cervical revisions, one mediastinal dissection, six cervicomediastinal dissections, two laparotomies). In 15 of 18 cases, tumor tissue was found in the previously suspected area. In ten cases serum calcitonin levels dropped postoperatively by 6%–75%. A normalization of the hormone level was achieved only once by yet another operation. During further follow-up, five of the reoperated patients died from their disease. The other 17 patients are being followed up, whereby calcitonin levels are elevated but there is no clinical or radiological evidence of tumor.Conclusions: Although in the patient cohort presented a normalization of serum calcitonin could be achieved only once, the authors consider SVC useful because it is the only means of localization of tumor tissue in cases of negative radiologic studies and therefore allows a planned approach to the operation procedure in these cases.  相似文献   
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Summary Four tumors of the spinal cord were induced with ethylnitrosourea in rats by transplacental administration and transplanted into the brains of animals of the same strain. One of these intracerebrally grafted tumor lines (G-XIII) was followed up over the first 10 passages and treated with CCNU and other alkylating drugs. The results were compared with findings in an earlier established line (G-XII) in passage 12 and 59, which in the first instance was sensitive to CCNU. The CCNU application prolonged survival in treated animals in various treatment schedules in the first 10 intracerebrally grafted generations of the tumor up to 59%. Induction times of tumors became increasingly shorter. The susceptibility of early passages was similar in both lines. Its loss in late passages went together with diffuse growth of the tumor and reticulin fiber production. In addition, glial fibrillary acid protein expression and formation of intermediate filaments in perivascular tumor cells was lost.  相似文献   
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This pilot study compared abdominal massage with laxative treatment in the management of constipation in 32 profoundly disabled, institutionalised adults. A randomised cross-over design was used. After an initial 16-day baseline measurement phase without any treatment, there followed two seven-week treatment phases separated by a one-week washout period. Each subject received seven weeks of massage and seven weeks on his or her previous laxative regimen. Primary outcome measures were gastro-intestinal and segmental transit times, measured at the end of the baseline phase and of each treatment phase. Secondary measures included stool frequency, size and consistency, the requirement for enemas and an assessment of patient well-being.The median value of total colonic transit time was 183 hours for the baseline phase and 159 hours for all treatment phases. There was no evidence of any statistically significant treatment differences between laxative and massage therapy for right, left or rectosigmoid segments either separately or in total. Analysis of secondary outcome measures also failed to find any treatment preferences.These results reveal the grossly abnormal colonic transit times of the study population at all times. The effects of laxative and massage therapy within this environment were not demonstrably different.  相似文献   
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