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61.
An optimization program for a remote after-loading system (RALS) for intracavitary treatment of cancer of the uterine cervix was established in 1982 by Tabushi and his co-workers. This system has been used in our hospital since 1986, using MODULEX. Seventy-three cases of untreated squamous cell carcinoma of the uterine cervix have been treated under RALS, 29 under conventional RALS and 44 under the RALS optimization program. The cumulative 5-year survival rates were obtained for the groups treated under each system by the Kaplan-Meier method. The 5-year survival rate of stage II cases treated under the RALS optimization program was 68.2%, and that of stage III cases 58.5%. On the other hand, that of stage II cases treated under conventional RALS was 56.3%, and that of stage III cases 44.9%. There was no significant difference between these two groups. Local control rates for stage II and III cases were higher than 5 year-survival rates. Among complications, the frequency of grade 2 radiation colitis was 15.9% with the RALS optimization program cases, and that of grade 2 radiation cystitis was 4.5%. We consider the RALS optimization program to be a clinically useful method for the intracavitary treatment of squamous cell carcinoma of the uterine cervix.  相似文献   
62.
This paper describes a numerical model developed to simulate flow and bed deformation around river hydraulic structures. The model solved the fully three-dimensional, Reynolds-averaged Navier–Stokes equation expressed in a moving boundary-fitted coordinate system to calculate the flow field with water and bed surfaces varying in time. A nonlinear k-ε turbulence model was employed in order to predict flow near the structure where three-dimensional flow is dominant. The temporal change in bed topography was calculated by coupling a stochastic model for sediment pickup and deposition using a momentum equation of sediment particles in order to account for the effect of nonequilibrium sediment transport. In validating the numerical model, a spur dike and a bridge pier, which are considered to be typical river-engineering structures, were selected. By comparing the numerical results with observed laboratory experimental data, the model was found to reproduce flow and scour geometry around these structures with sufficient accuracy.  相似文献   
63.
The unitraveling-carrier photodiode (UTC-PD) is a novel photodiode that utilizes only electrons as the active carriers. This unique feature is the key for its ability to achieve excellent high-speed and high-output characteristics simultaneously. To date, a record 3-dB bandwidth of 310 GHz and a millimeter-wave output power of over 20 mW at 100 GHz have been achieved. The superior capability of the UTC-PD for generating very large high-bit-rate electrical signals as well as a very high RF output power in millimeter/submillimeter ranges can lead to innovations in various systems, such as broadband optical communications systems, wireless communications systems, and high-frequency measurement systems. Accomplishments include photoreceivers of up to 160 Gb/s, error-free DEMUX operations using an integrated UTC-PD driven optical gate of up to 320 Gb/s, a 10-Gb/s millimeter-wave wireless link at 120 GHz, submillimeter-wave generation at frequencies of up to 1.5 THz, and photonic frequency conversion with an efficiency of -8 dB at 60 GHz. For the practical use, various types of modules, such as a 1-mm coaxial connector module, a rectangular-waveguide output module, and a quasi-optic module, have been developed. The superior reliability and stability are also confirmed demonstrating usefulness of the UTC-PD for the system applications.  相似文献   
64.
In this study, niobium‐doped titanium oxide (TNO) was employed for a novel transparent conductive oxide (TCO) film to construct a porous‐TiO2/TNO homojunction in a dye‐sensitized solar cell (DSSC). However, considering a balance between the electrical and optical properties of the TCO film, the sheet resistance in TNO was tuned to be higher than that in a typical fluorine‐doped tin oxide (FTO). The photovoltaic performance of the cell with the TNO film (TNO cell) was optimized to be almost comparable to that with a conventional FTO film (FTO cell) by coating the surface of the porous‐TiO2 layer with a thin alumina or magnesia film to block a back reaction within the cell. An electrochemical impedance measurement was conducted to determine the detailed photovoltaic performance from the viewpoint of electron transportation in the cell. R1, the real part of ω1, indicated that electron transportation at the porous‐TiO2/TNO interface was more favorable than that at the porous‐TiO2/FTO interface, which was supported by AC phase change in the cell at a high‐frequency range. We found that the homojunction newly introduced in the cell is one of the key concepts for developing a DSSC into a high‐performance photovoltaic device.  相似文献   
65.
The matrix metalloproteinases (MMPs) are a homologous family of zinc proteinases that are collectively capable of catabolising the various macromolecular components of the extracellular matrix including collagens. In this study an MMP was successfully isolated and purified from ostrich skeletal muscle using Toyopearl Super Q-650S, hydroxylapatite and zinc-chelate chromatographies. The purified molecule had a molecular weight of 55K and a total of 467 amino acid residues. Purified ostrich MMP showed a pH optimum of 7 and a temperature optimum of 45°C. The activity of purified ostrich MMP was shown to be inhibited by metal chelators (1,10 phenanthroline and EDTA) and partially inhibited by soy bean trypsin inhibitor. All the functional properties of ostrich MMP were compared to previously reported values for MMPs from other sources. The MMP activities in ostrich meat during a 21-day ageing period were determined and an overall increase in MMP activities was observed.  相似文献   
66.
The detection and quantification of ionizing radiation damage to DNA at a single-molecule level by atomic force microscopy (AFM) is reported. The DNA damage-detection technique combining supercoiled plasmid relaxation assay with AFM imaging is a direct and quantitative approach to detect gamma-ray-induced single- and double-strand breaks in DNA, and its accuracy and reliability are validated through a comparison with traditional agarose gel electrophoresis. In addition, the dependence of radiation-induced single-strand breaks on plasmid size and concentration at a single-molecule level in a low-dose (1 Gy) and low-concentration range (0.01 ng microL(-1)-10 ng microL(-1)) is investigated using the AFM-based damage-detection assay. The results clearly show that the number of single-strand breaks per DNA molecule is linearly proportional to the plasmid size and inversely correlated to the DNA concentration. This assay can also efficiently detect DNA damage in highly dilute samples (0.01 ng microL(-1)), which is beyond the capability of traditional techniques. AFM imaging can uniquely supplement traditional techniques for sensitive measurements of damage to DNA by ionizing radiation.  相似文献   
67.
68.
The reliability of InP/InGaAs uni-travelling-carrier photodiodes has been studied. A failure rate of 42 FIT at 25°C was estimated from long-term bias-temperature stress tests. Stable operations for over 2000 h were also confirmed under higher-power optical input conditions  相似文献   
69.
The Symptom Check-List-90 (SCL-90) is a widely used psychiatric questionnaire which has not yet been validated in Finland. We investigated the utility of the translated version of the SCL-90 in the Finnish population, and set community norms for it. The internal consistency of the original subscales was checked and found to be good. Discriminant function analysis, based on the nine original subscales, showed that the power of the SCL-90 to discriminate between patients and the community is good. Factor analysis of the items of the questionnaire yielded a very strong unrotated first factor, suggesting that a general factor may be present. This together with the fact that high intercorrelations were found between the nine original subscales suggests that the instrument is not multidimensional. The SCL-90 may be useful in a research setting as an instrument for measuring the change in symptomatic distress, or as a screening instrument. The American community norms should be used with caution, as the Finnish community sample scored consistently higher on all subscales.  相似文献   
70.
The accumulation of abnormal prion protein in follicular dendritic cells did not occur in mice inoculated with materials from human Creutzfeldt-Jakob disease, whereas it always occurred in mice inoculated with mouse-adapted agents, suggesting an intense expression of the species barrier in the lymphoreticular system.  相似文献   
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