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The dynamic signal intensity changes at magnetic resonance (MR) imaging in active and chronic wallerian degeneration in the corticospinal tract were evaluated. Forty-three patients with wallerian degeneration seen on MR images after cerebral infarction were studied. When possible, patients with acute stroke were examined with MR imaging prospectively at the onset of symptoms and then at weekly intervals for several months. Focal infarction without distal axonal degeneration is demonstrated for the 1st month following onset of clinical symptoms. At 4 weeks, a well-defined band of hypointense signal appears on T2-weighted images in the topographic distribution of the corticospinal tract. After 10-14 weeks, the signal becomes permanently hyperintense. Over several years, accompanying ipsilateral brain stem shrinkage occurs. The dark signal intensity observed on T2-weighted images between 4 and 14 weeks is believed to result primarily from transitory increased lipid-protein ratio.  相似文献   
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OBJECTIVE: The objective of this study was to evaluate the long-term effects of anti-TNF-alpha treatment on temporomandibular joints (TMJs), oral mucosa, and salivary flow in RA. STUDY DESIGN: Seventeen patients received infusions of TNF-alpha blocking agents after 0, 2, and 6 weeks, and then every 8 weeks until week 54 (follow-up). Clinical dysfunction index (Di) for the TMJ system, salivary flow, disease activity score (DAS28), and other medical assessments were calculated at weeks 0 and 54. RESULTS: Median Di was 5.0 (range 0-21) at baseline and 1.0 (range 0-6) (P = .001) at follow-up. Mean salivary flow was 3.2 mL/15 minutes at baseline and 4.6 at follow-up (P = .055). Two (11.7%) of the patients developed oral candidiasis during the period of treatment. The median DAS28 was 6.2 (range, 4.7-7.7) at baseline and 4.1 (range, 1.6-6.8) at follow-up (P = .001). CONCLUSION: We conclude that anti-TNF-alpha blocking treatments have beneficial effects on oral as well as general manifestations of RA.  相似文献   
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Endometriosis in women at interval sterilization   总被引:6,自引:0,他引:6  
The prevalence of endometriosis was investigated in 108 Norwegian women admitted for interval tubal sterilization. The mean age of the patients was 37 years. Endometriosis was detected in 19 (18%) of the women. About one-half of these had no symptoms from the disease. A positive correlation was found between a retroversion of the uterus and endometriosis. The women with endometriosis showed a longer period of uninterrupted menstrual cycles prior to the time of sterilization, when compared with the controls (89 unaffected women). Sisters and mothers of patients with endometriosis displayed a higher frequency of benign gynecological disorders than the corresponding relatives of the control group. The prevalence of endometriosis appeared to be independent of the following clinical parameters: onset of menarche, age at first pregnancy, number of pregnancies, previous use of hormonal contraceptives or IUD, and actual age at the time of sterilization.  相似文献   
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Disseminated neuroblastoma is a malignancy of children often treated by intensive chemotherapy/radiotherapy followed by autologous bone marrow transplantation (ABMT). A high proportion of those treated subsequently relapse. It is unknown if relapse is a consequence of residual disease in the patient or of contaminating malignant cells remaining in the infused marrow, which, of necessity, is harvested and stored prior to ablative chemotherapy/radiotherapy. The assumption that residual cells in the infused marrow contribute to relapse has lead to the adoption of marrow purging prior to reinfusion. However, neither the necessity nor the efficacy of the procedure have been established. We now show how retroviral-mediated gene transfer using the LNL6 vector may resolve this issue. Clonogenic neuroblastoma cells in patient marrow can be transduced and the NEOR gene detected by observing individual neuroblastoma cell colony growth in G418, and by polymerase chain reaction (PCR) of individual colonies. Efficiency of transduction is between 0 and 13.5%. If marrow is exposed to LNL6 prior to infusion and marked cells are detected at the time of relapse, this would demonstrate that infused marrow contributed to disease recurrence. The technique could then be used to analyze the efficacy of marrow purging techniques. Since normal progenitor cells from these patients are also marked, the technique can be used to study factors that modify reconstitution and transducibility of infused marrow. Clinical studies using this approach have now begun.  相似文献   
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To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation.  相似文献   
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