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91.
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PURPOSE: We demonstrate the effect of chronic inflammation of the prostate on the ratio of free-to-total prostate specific antigen (PSA) in serum calculated as a percentage of free PSA and, therefore, that percentage of free PSA is an unspecific means to distinguish among prostate cancer, chronic prostatitis and benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Total, free and percentage of free PSA was measured in 66 men with prostate cancer, 119 with BPH and 17 with asymptomatic chronic prostatitis. In all patients the diagnosis was histopathologically confirmed by microscopic examination of prostatic specimens after sextant biopsy, transurethral prostatic resection or prostatectomy. RESULTS: The median values of total, free and percentage of free PSA were 4.11 microg./l., 0.75 microg./l. and 20.4% in patients with BPH, 10.0 microg./l., 0.84 microg./l. and 8.5% in those with prostate cancer, and 7.60 microg./l., 1.23 microg./l. and 10.6% in those with chronic prostatitis. Patients with prostate cancer and chronic prostatitis had a significantly lower percentage of free PSA than those with BPH. Receiver operating characteristics curve analysis showed that percentage of free PSA as a discriminator between prostate cancer and BPH was not suitable for differentiating between prostate cancer and chronic prostatitis. CONCLUSIONS: Chronic prostatitis is not characterized by elevated total PSA concentrations alone but also by a decreased percentage of free PSA, a tendency similar to that in prostate cancer. This unspecific change in percentage of free PSA must be considered to interpret the percentage of free PSA correctly.  相似文献   
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The employment of the Zn(Se,Te) pseudo-graded contacting scheme to p-type ZnSe-based alloys contributes directly to the recent demonstration of room temperature continuous-wave operation of II– VI green-blue laser diodes. Contact ohmicity is maintained down to cryogenic temperatures which enabled the investigation of electrical transport properties associated with the p-type nitrogen-doped ZnSe, Zn(S,Se), and (Zn,Mg)(S,Se). The observation of both persistent photoconductivity and a metastable population of holes which are in thermodynamic equilibrium with hydrogenic acceptors having reduced activation energy suggests the presence of a DX-like behavior for holes in p-type (Zn,Mg)(S,Se).  相似文献   
96.
We report on high-resolution linewidth measurements of proton-implanted InGaAs-GaAs VCSELs employing the delayed self-heterodyne method. Devices with 16-/spl mu/m active diameter exhibit record low linewidths of 20 MHz and 4-MHz residual linewidth. The linewidth enhancement factor is accurately determined from the ratio of induced phase to amplitude modulation indexes.  相似文献   
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Niobium nitride superconducting films have been deposited by reactive rf magnetron sputtering. Polyepitaxial growth on MgO-coated substrates greatly improves the superconducting properties. The overall film resistivity is found to be widely dependent on the total pressure of the gas mixture. Samples with a negative temperature coefficient of resistance exhibit 3D weak localization effects as characterized by magnetoresistance measurements. The inelastic scattering time is found to vary as T–p with p2, in the temperature range Tc-3Tc.Laboratoire associé au C.N.R.S.  相似文献   
99.

Predicting remaining useful life (RUL) is crucial for system maintenance. Condition monitoring makes not only degradation data available for RUL estimation but also categorized health status data for health state identification. However, RUL prediction has been treated as an independent process in most cases even though potential relevance exists with health status detection process. In this paper, we propose a convolution neural network based multi-task learning method to reflect the relatedness of RUL estimation with health status detection process. The proposed method applied to the C-MAPSS dataset for aero-engine unit prognostics supported superior performances to existing baseline models.

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100.
Recently, watermarking based data transmission techniques using terrestrial digital TV signal have been proposed since they are also cost-free and can overcome the limitations of GPS. However, in the previous watermarking based methods, the detection accuracy is low and additional data rate is too low. Thus, we propose the throughput enhancement method by employing the TZCD-MBOK watermarking technique in T-DMB system. By applying the proposed scheme to T-DMB, it allows additional data transmission for disaster broadcasting and improves efficiency of data transmission in shadow region and indoor to mobile environment through watermarking spread code. From the simulation results, we confirm the proposed watermarking scheme affected on the existing T-DMB signal. Moreover, it was also confirmed that the system capacity increases as the power of additional watermarking signal rose. The results of the paper can be applied to wireless multimedia digital broadcasting systems.  相似文献   
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