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OBJECTIVE: To study electroencephalography-electromyography (EEG-EMG) relationships in patients with different forms of progressive myoclonic epilepsies (PME). METHODS: EEG-EMG auto-spectra, coherence and phase functions were estimated by means of bivariate and time varying autoregressive (AR) models in 15 patients: 8 with Unverricht-Lundborg, 4 with Lafora body disease, and 3 with sialidosis. RESULTS: The coherence spectra of the EMG epochs including action myoclonus and contralateral frontocentral EEG derivations showed a main beta peak (average coherence: 0.60-0.79) in all patients, regardless of the type of PME. The time lag from cortex to muscle was 13.0-21.3 ms. Significantly, coherent gamma activity was consistently found only in the 3 patients with sialidosis; the most heterogeneous results were obtained in the patients with Lafora disease, who showed a more complex coherence profile. Periods of normal muscle contractions, which could be recorded in patients with Unverricht-Lundborg PME, were characterised by the presence of an EEG-EMG beta coherence peak on the same frequency as in the case of action myoclonus, but with a lower coherence value. CONCLUSIONS: AR models were capable of describing EEG-EMG relationships in patients with PME, and indicated that coherent cortical and EMG beta oscillations are crucially involved in the generation of myoclonus. Moreover, they could detect the uneven spectral profiles characterising the different forms of PME.  相似文献   
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Among the many effects of family planning is the influence ithas on mortality and morbidity in women and children throughthe mechanism of changing the number and spacing of children.There is a complex set of relationships between mother's age,parity, birth spacing and infant and child mortality and morbidity.Much effort has been put into untangling this web in the hopeof identifying clear causal connections, but for the most parton the basis of inadequate data. Rather than attempt to establishthe relative importance of child spacing as a cause of decreasesin mortality, this paper takes as its starting point that thereis a connection, and presents some possible causal mechanismswhich explain how short birth intervals and child mortalitycould be related. In addition the most frequently cited hypotheses-maternaldepletion and sibling competition-a third is examined-birthcrowding which, it is suggested, influences the pattern of thetransmission of infectious diseases and, in turn, mortality. In the field of maternal mortality, the data which could beused to quantify the benefits of family planning are in evenshorter supply; however, the causal connections are rather moreeasily identified. The final section combines parity-specificdata on maternal mortality with evidence of changes in fertilitypatterns brought about by family planning to assess how successfulwe can hope to be in reducing through birth control the numberof women who die in childbirth.  相似文献   
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In 22 patients with malignancies, treated with high-dose chemoradiotherapy and autologous bone marrow transplantation (BMT), peripheral blood T cell subsets and functions were studied. In ten cytomegalovirus (CMV)-negative patients, CD4+ and CD8+ T cells (representing T cells of the helper/inducer phenotype and T cells of the suppressor/cytotoxic phenotype, respectively), recovered slowly and simultaneously. In 12 CMV-positive patients, however, CD8+ T cells recovered more rapidly than CD4+ T cells and rose to increased counts. No T cells with an immature phenotype (CD1+, OKT6+) were observed. Lymphocyte stimulation by herpes simplex virus infected fibroblasts (and by CMV-infected fibroblasts in CMV-positive patients) in contrast remained high and even increased after BMT in both groups. These data indicate that T cell recovery after autologous BMT is mainly due to proliferation of mature T cells present in the BM graft and not to generation of new T cells from T cell precursors.  相似文献   
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Background

Counseling in combination with pedometer use has proven to be effective in increasing physical activity and improving health outcomes. We investigated the cost-effectiveness of this intervention targeted at one million insufficiently active adults who visit their general practitioner in the Netherlands.

Methods

We used the RIVM chronic disease model to estimate the long-term effects of increased physical activity on the future health care costs and quality adjusted life years (QALY) gained, from a health care perspective.

Results

The intervention resulted in almost 6000 people shifting to more favorable physical-activity levels, and in 5100 life years and 6100 QALYs gained, at an additional total cost of EUR 67.6 million. The incremental cost-effectiveness ratio (ICER) was EUR 13,200 per life year gained and EUR 11,100 per QALY gained. The intervention has a probability of 0.66 to be cost-effective if a QALY gained is valued at the Dutch informal threshold for cost-effectiveness of preventive intervention of EUR 20,000. A sensitivity analysis showed substantial uncertainty of ICER values.

Conclusion

Counseling in combination with pedometer use aiming to increase physical activity may be a cost-effective intervention. However, the intervention only yields relatively small health benefits in the Netherlands.  相似文献   
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A murine hybridoma clone is described that grows continuously in culture and produces a monoclonal antibody we have called Royal Free Monoclonal Antibody to factor IX No. 1 (RFF-IX/1). This has high affinity for a coagulation site on factor IX. RFF-IX/1 immobilised on sepharose can be used to deplete factor IX from normal human plasma. This immunoaffinity depleted plasma is indistinguishable from severe Christmas disease plasma and can be used as the substrate in a one stage coagulation assay for factor IX. The affinity column has high capacity and can be regenerated so that large scale production from normal plasma of factor IX deficient plasma as a diagnostic reagent is now feasible.  相似文献   
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