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Maha H. Hussain M.D. Isaac Powell M.D. Nagi Zaki M.D. M.S. Zocia Maciorowski M.S. Wael Sakr M.D. Mark Kukuruga B.S. Daniel Visscher M.D. Gabriel P. Haas M.D. J. Edson Pontes M.D. John F. Ensley M.D. 《Cancer》1993,72(10):3012-3019
Background. DNA ploidy analysis has been investigated as a prognostic indicator in prostate cancer. Most of the data is derived from retrospective studies using paraffin-embedded tissue. This method has drawbacks related to the quality of DNA histograms and uncontrolled data collection. Methods. DNA ploidy analysis of freshly resected prostatic tissue was prospectively compared with conventional prognostic variables in 97 men treated with radical prostatectomy for localized prostate cancer. Results. Regarding the patients, 31.9% were African American and 66% had pathologic Stages C or D1 disease. Only 9.6% of patients with Stages A2 and B had a prostate-specific antigen (PSA) value greater than 10 ng/ml, whereas 97% of patients with PSA values greater than 20 ng/ml had pathologic Stages C and D1. PSA levels correlated with Gleason score (P = < 0.05); 51% and 100% of patients with Gleason score 5–7 and 8–10, respectively, had PSA values greater than 10 ng/ml. Twenty-two patients (23%) had DNA aneuploid tumors. Comparisons of mechanical to enzymatic cell suspensions indicated that DNA aneuploidy was better preserved in mechanical cell preparations. DNA ploidy correlated with pathologic stage (P = < 0.05) and Gleason score (P = < 0.05). Fifteen of 79 patients (18.9%) with Gleason score 5–7 had DNA aneuploid tumors versus 71.4% of patients with Gleason score 8–10. PSA groups correlated with ploidy status (P = 0.01). Although the majority of patients (19 of 22) with DNA aneuploid tumors had elevated preoperative PSA levels, none had a PSA value greater than 50 ng/ml. Conclusions. DNA ploidy analysis correlated with established prognostic indicators in prostate cancer; however, its independent correlation with natural history and treatment outcome must be established for it to have an effect on therapeutic decisions. 相似文献
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Mixed blocked/event-related designs separate transient and sustained activity in fMRI 总被引:6,自引:0,他引:6
Visscher KM Miezin FM Kelly JE Buckner RL Donaldson DI McAvoy MP Bhalodia VM Petersen SE 《NeuroImage》2003,19(4):1694-1708
Recent functional magnetic resonance imaging (fMRI) studies using mixed blocked/event-related designs have shown activity consistent with separable sustained task-related processes and transient trial-related processes. In the mixed design, control blocks are intermixed with task blocks, during which trials are presented at varying intervals. Two studies were conducted to assess the ability of this design to detect and dissociate sustained task-related from transient trial-related activity. Analyses on both simulated and empirical data were performed by using the general linear model with a shape assumed for sustained effects, but not transient effects. In the first study, simulated data were produced with sustained time courses, transient time courses, and the sum of both together. Analyses of these data showed appropriate parsing of sustained and transient activity in all three cases. For the empirical fMRI experiment, counterphase-flickering checkerboard stimuli were constructed to produce sustained, transient, and combined sustained and transient responses in visual cortex. As with the simulation, appropriate parsing of sustained and transient activity was seen in all three cases; i.e., sustained stimuli produced sustained time courses and transient stimuli produced transient time courses. Combined stimuli produced both transient and sustained time courses. Critically, transient stimuli alone did not produce spurious positive sustained responses; sustained stimuli alone produced negligible spurious transient time courses. The results of these two studies along with supplemental simulations provide strong evidence that mixed designs are an effective tool for separating transient, trial-related activity from sustained activity in fMRI experiments. Mixed designs can allow researchers a means to examine brain activity associated with sustained processes, potentially related to task-level control signals. 相似文献
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Cleusa P Ferri Sandro S Mitsuhiro Marina CM Barros Elisa Chalem Ruth Guinsburg Vikram Patel Martin Prince Ronaldo Laranjeira 《BMC public health》2007,7(1):209