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CONTEXT: The generalizability of currently available estimates of survival after radical prostatectomy is theoretically limited. OBJECTIVE: To obtain generalizable estimates of survival after radical prostatectomy. DESIGN: A population-based retrospective cohort study. SETTING: Nine regions of the United States. PATIENTS: Patients who were diagnosed with prostate cancer between 1983 and 1987 and underwent radical prostatectomy and lymph node dissection. MAIN OUTCOME MEASURES: Proportional hazards models incorporating geographical region, age, race, pathological stage, lymph node involvement, and tumor grade to identify independent correlates of disease-specific and overall survival and life table analyses to estimate 10-year survival distributions. RESULTS: A total of 3626 patients with a mean age of 65 years were included in the study; 92.6% were white, 54.2% had moderate-grade cancer, 60.4% had no extension beyond the prostate, and 91.2% had no lymph node involvement. Using San Francisco-Oakland, Calif, as a reference region, no other region was significantly associated with a risk of disease-specific or overall mortality. Older age and black race were independently associated with worse overall but not disease-specific survival. Higher grade, extension beyond the prostate, and lymph node involvement were independently associated with worse disease-specific and overall survival. Estimates of 10-year disease-specific survival ranged from 75% to 97% for patients with well-differentiated and moderately differentiated cancers and from 60% to 86% for patients with poorly differentiated cancers. CONCLUSIONS: Neither disease-specific nor overall survival varied by region, suggesting geographically uniform assessments of risk in patient selection for radical prostatectomy. Across regions, overall survival varied by patient and prostate cancer characteristics while disease-specific survival varied substantially by prostate cancer but not patient characteristics. The present analyses provide the most generalizable current estimates of survival after radical prostatectomy.  相似文献   
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This paper presents a CMOS inverter-based class-AB pseudo-differential amplifier comprising current-mode common-mode feedback (CMFB). The circuit employs two CMOS inverters and the complementary CMFB consisting of current-mode common-mode (CM) detector and transimpedance amplifier. The circuit has been designed using 0.18 μm CMOS technology and operates at 1 V supply. The simulation results demonstrate rail-to-rail operation with low CM gain (?15 dB). The power dissipation of the circuit is 102.5 μW.  相似文献   
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A new current-mode pseudo exponential-control variable-gain amplifier (VGA) using CMOS technology is proposed. The technique is based on the fourth-order Taylor's series approximation. The VGA exhibits a linear-dB controllable output range of 30 dB with maximum error less than 0.5 dB.  相似文献   
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In this paper, the authors present a high-frequency model for the high electron mobility transistor (HEMT). The model includes the distributed effects in the channel of the device through two newly developed wave equations in the linear and saturation regimes. The equations are solved taking into account the electric fields along and perpendicular to the flow of the current. The Y and S parameters are derived and the theoretical predictions of the model are compared with the experimental data and shown to be in good agreement over a wide range of frequencies  相似文献   
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OBJECTIVE: To study factors related to recurrent laryngeal nerve (RLN) paralysis, a major complication of thyroidectomy. DESIGN: Retrospective study of outcome of patients' medical records. PATIENTS AND METHODS: Records of 361 patients who underwent thyroidectomy by otolaryngologists at Ramathibodi Hospital were reviewed for RLN paralysis. Main Outcome Measures: RLN injury was analyzed in relation to types of surgery, RLN identification, and histopathology. The analysis was based on the number of RLNs at risk. RESULTS: The incidence of permanent RLN paralysis was 2.38%. Both the permanent RLN paralysis and temporary RLN paralysis were significantly related to the histopathologic findings of malignancy (p < .005). The positive identification of RLN and the types of surgery were not found to be significant factors in either permanent RLN paralysis or temporary RLN paralysis. CONCLUSIONS: There was insufficient evidence to support that the identification of RLNs during surgery would be a significant factor in reducing the likelihood of RLN paralysis. However, RLNs should be identified to avoid iatrogenic injury and subsequent paralysis. Meticulous surgical technique should be applied in patients whose results of fine-needle aspiration biopsy suggested malignancy, as there is the possibility of difficult surgery and potential iatrogenic RLN paralysis in this group of thyroid patients.  相似文献   
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In this paper, the equivalent circuit model of a multilayer piezoelectric transformer (MPT) has been proposed and MPT has also been fabricated using PMS-PZT to investigate the load and frequency characteristics. The model taking into account the loss and the shift of resonant frequency due to the change of a stiffness caused from the lamination is developed based on Mason’s equivalent circuit. The symbolic expressions were derived from the model. To verify the accuracy of the proposed equivalent circuit model, MPT have been simulated. The simulation results have been compared with the experimental data. They are shown to agree well over a wide range of various frequency and the load resistance.  相似文献   
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Scanning electron micrographs of the granules of 54 starches obtained from a wide variety of plant sources, consisting of roots and tubers, grains, maize, peas and beans, fruits and nuts, and small granule starches, are presented as a comparative study of their sizes and morphologies. All micrographs are presented at a magnification of 1500X with the addition of micrographs of 600X for the very large granules and micrographs of 10,000X for the very small granules.  相似文献   
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