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With the availability of novel agents, the overall survival (OS) in patients diagnosed with multiple myeloma (MM) has improved over the last decade. Data on 40,294 MM patients in the years from 1973 to 2003 were obtained from the Surveillance, Epidemiology, and End Results Program (SEER) of the US National Cancer Institute. Statistical analyses evaluating gender, race, age, and year of diagnosis were performed using univariate and multivariate Cox regression models for the OS endpoint. The mean patient age at diagnosis was 68.3 years. Mean survival was 30 months (median = 19 months). Asian/Pacific Islander race was associated with an improved OS, HR 0.90 (CI 0.86–0.95, P < 0.001). American Indian/Alaska Native race was associated with a decreased OS, HR 1.18 (CI 1.01–1.38, P = 0.040). Multivariate analysis did not reveal statistically significant differences in OS between patients in the white and black race (P = 0.709). Younger age (age <65, and 65–75) was associated with improved OS when compared with patients >75 years of age (all P < 0.001). Recent treatment decades (1983–1992 and 1993–2003) were associated with improved OS on multivariate analysis with HR 0.88 (CI 0.88–0.89, P < 0.001) and HR 0.83 (CI 0.81–0.85, P < 0.001), respectively. As the largest population analysis to date, this study reveals a statistically significant improvement in OS for patients who were treated in more recent decades, even before the availability of novel agents. Patients who were <65 years of age and Asian/Pacific Islander race groups exhibited superior levels of OS, whereas American Indian/Alaska Native groups had decreased OS.  相似文献   
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Local alpha-band synchronization has been associated with both cortical idling and active inhibition. Recent evidence, however, suggests that long-range alpha synchronization increases functional coupling between cortical regions. We demonstrate increased long-range alpha and beta band phase synchronization during short-term memory retention in children 6–10 years of age. Furthermore, whereas alpha-band synchronization between posterior cortex and other regions is increased during retention, local alpha-band synchronization over posterior cortex is reduced. This constitutes a functional dissociation for alpha synchronization across local and long-range cortical scales. We interpret long-range synchronization as reflecting functional integration within a network of frontal and visual cortical regions. Local desynchronization of alpha rhythms over posterior cortex, conversely, likely arises because of increased engagement of visual cortex during retention.  相似文献   
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1. The metabolic fate of the model ecotoxin 3-trifluoromethylaniline (3-TFMA) in earthworm was studied by 19 F- and directly coupled 19 F/ 1 H-HPLC-NMR spectroscopy. Earthworms of Eisenia veneta spp. were subjected to the ecotoxin during a filter papercontact toxicity test at exposure levels of 1000, 100, 10, 1 and 0.1 µg cm -2. A metabolic profile was obtained previously by 19 F-NMR spectroscopy and metabolites were observed at all the exposure levels. 2. Identification of metabolites in individual worm extracts at the (lethal) exposure levels of 1000 and 100 µg cm -2 could be achieved on-line without sample preparation by 19 F/ 1 H-HPLC-NMR spectroscopy. 19 F-HPLC-NMR spectroscopy was used in the continuous-flow mode, which enabled the HPLC chromatographic retention times (t R) of the metabolites to be established in a single analytical step. 3. In total, three 19 F-NMR signals could be detected, of which one was identified as the parent compound. Two earlier eluting metabolites were identified to be α - and β -glucoside conjugates of 3-TFMA. 4. Metabolites at the lower (sublethal) exposure levels of 10, 1 and 0.1 µg cm -2 escaped identification by 19 F/ 1 H-HPLC-NMR spectroscopy as outlined here and will require concentration prior to analysis.  相似文献   
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