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991.
992.
S Ambiru M Miyazaki H Ito K Nakagawa H Shimizu Y Nukui S Nozawa A Okuno H Yoshitomi N Nakajima 《Canadian Metallurgical Quarterly》1997,42(8):1660-1665
The purpose of this prospective study was to evaluate the prognostic value of the type IV collagenase (IVase) activity in colorectal cancer tissue on disease-free and overall survival in 31 colorectal cancer patients. The clinicopathologic factors studied for prognostic value were age, tumor location, tumor differentiation, preoperative serum levels of carcinoembryonic antigen, Dukes' stage, and IVase activity in colorectal cancer tissue. IVase activities in colorectal cancer tissue were significantly higher in the group of patients with recurrences than in the group without recurrences (P = 0.019). Patients with high IVase activity in colorectal cancer tissue had a significantly shorter disease-free survival (P = 0.0016) and overall survival (P = 0.022) time than those with low IVase activity. Univariate and multivariate analysis showed that significant prognostic factors for disease-free survival were Dukes' stage (P = 0.029, P = 0.046, respectively) and IVase activity status (P = 0.0016, P = 0.0026, respectively). With respect to overall survival, only IVase activity status provided significant predictive value in multivariate analysis (P = 0.041). This prospective study suggests that IVase activity is a valuable prognostic factor in colorectal cancer patients. 相似文献
993.
Formal specifications can help resolve both ambiguity issues and correctness problems in verifying complex hardware designs. This new methodology shows how specifications can also help design productivity by automating many procedures that are now done manually. Input sequences, output assertions, and a simulation coverage metric for the design under verification are all generated directly from the specification 相似文献
994.
A novel hybrid amplifier with the largest reported seamless gain-bandwidth of 76 nm (1462-1538 nm) and a peak gain of 31.5 dB is described. The amplifier has a low noise figure, high output power, and a dispersion-compensation function at a signal rate of 10 Gbit/s with an 80 km single mode fibre, over the entire gain bandwidth 相似文献
995.
996.
Y Wakisaka M Muro T Kabutomori H Takeda S Shimizu S Ino T Ifukube 《Canadian Metallurgical Quarterly》1997,5(2):148-157
As power sources for rehabilitation equipment, electric, hydraulic, and pneumatic actuators have been used. However a more human-sized and higher powered actuator that can reduce the equipment size is desired. A new metal hydride (MH) actuator that uses the reversible reaction between the heat energy and mechanical energy of a hydrogen absorbing alloy has recently attracted much attention. The MH actuator is characterized by its small size, low weight, noiseless operation and a compliance similar to that of the human elbow joint. Therefore, the MH actuator has the characteristic of being light and easy to use and so is suitable for use in medical and rehabilitation applications. Some lifting devices using this actuator have already been developed and are being used for the care of the aged and disabled. The characteristics of the MH actuator are presented and then some applications are introduced in this paper. It is our opinion that in our aging society the MH actuator will play an important role in the development of medical and rehabilitation equipment. 相似文献
997.
H Shimizu R Yagi Y Kimura K Makino H Terato Y Ohyama H Ide 《Canadian Metallurgical Quarterly》1997,25(3):597-603
OBJECTIVES: The aims of the study were to 1) assess the effects of 12 weeks of exercise training at low work loads (i.e., corresponding to < or = 50% of peak oxygen consumption [Vo2]) on peak Vo2 and hyperemic calf blood flow in patients with severe congestive heart failure; and 2) evaluate left ventricular diastolic pressure and wall stress during exercise performed at work loads corresponding to < or = 50% and 70% to 80% of peak Vo2. BACKGROUND: Whether the benefits of exercise training can be achieved at work loads that result in lower left ventricular diastolic wall stress than those associated with conventional work loads is unknown in patients with severe congestive heart failure. METHODS: Sixteen patients with severe congestive heart failure trained at low work loads for 1 h/day, four times a week, for 12 weeks. Peak Vo2 and calf and forearm reactive hyperemia were measured before and during training. Nine of the 16 patients underwent right heart catheterization and echocardiography during bicycle exercise at low and conventional work loads (i.e., 50% and 70% to 80% of peak Vo2, respectively). RESULTS: The increase in left ventricular diastolic wall stress was substantially lower during exercise at low work loads than during exercise at conventional work loads, (i.e., [mean +/- SEM] 23.3 +/- 7.4 vs. 69.6 +/- 8.1 dynes/cm2 (p < 0.001). After 6 and 12 weeks of training, peak Vo2 increased from 11.5 +/- 0.4 to 14.0 +/- 0.5 and 15.0 +/- 0.5 ml/kg per min, respectively (p < 0.0001 vs. baseline for both). Peak reactive hyperemia significantly increased in the calf but not in the forearm. The increases in peak Vo2 and calf peak reactive hyperemia correlated closely (r = 0.61, p < 0.02). CONCLUSIONS: In patients with severe congestive heart failure, peak Vo2 is enhanced by exercise training at work loads that result in smaller increases in left ventricular diastolic wall stress than those observed at conventional work loads. 相似文献
998.
M Matsushima RE LaPorte M Maruyama K Shimizu R Nishimura N Tajima 《Canadian Metallurgical Quarterly》1997,40(2):212-216
The aim of this study was to evaluate the geographic variation in mortality among individuals with youth-onset insulin-dependent diabetes mellitus (IDDM) across the world. The study was based on the currently available IDDM incidence and mortality data. Mortality data for diabetes in the 0-24 year age group were obtained from the World Health Organization (WHO) statistics. The mortality rates were adjusted for the frequency of occurrence of IDDM and dividing the mortality rates by the IDDM incidence rates which were obtained from the WHO DiaMond project. There was a more than 10-fold geographic variation in mortality between the developed countries and Eastern European populations. The areas with the highest mortality rates were located in Japan, Eastern Europe and Russia. The areas having the best outcome associated with IDDM were Northern Europe, Central Europe, and Canada. An ecological study demonstrated a relationship between the incidence-adjusted mortality (estimated case-fatality) with IDDM incidence itself (Spearman's correlation coefficient = 0.45) as well as infant mortality and life expectancy at birth. These data demonstrated the possibility of an enormous geographic variation in mortality of youth-onset diabetic patients even in developed countries. It is important to note that these excess deaths are potentially preventable. The ecological study also suggested that the mortality differences may be in part related to overall and diabetes related care. 相似文献
999.
M Shimizu H Akamatsu T Yoshizaki H Tanaka T Sakamoto M Sunamori 《Canadian Metallurgical Quarterly》1997,45(12):1972-1975
A 51-year-old woman was admitted because of general fatigue assumed to be due to climacteric disturbance. Laboratory examinations suggested a diagnosis of hyperparathyroidism based on high serum levels of Ca, intact PTH, and high-sensitivity PTH. No abnormalities were found in the cervix. Chest X-ray films and CT scans showed a mass measuring 4 cm in the right postero-upper mediastinum. The tumor was positive on a parathyroid scintigram, and was diagnosed as a mediastinal parathyroid adenoma with hyperparathyroidism. Operative findings showed a tumor surrounded by the superior vena cava, vagus nerve, azygos vein, and brachiocephalic artery. Careful resection of the hypervascular tumor from surrounding tissues was performed using a thoracoscopic technique alone. The postoperative course was uneventful. Serum values of Ca, intact PTH, and high-sensitivity PTH decreased to within normal ranges. after surgery. Pathohistological study confirmed the diagnosis of parathyroid adenoma including a cyst caused by degeneration of the tumor. 相似文献
1000.
Recent progress in long-span optical repeater systems indicates that the polarization-mode dispersion (PMD) influence has become one of the main degradation factors in high speed and wideband systems. This paper discusses polarization-control methods for suppressing the PMD influence for both the coherent FDM system and the IM-DD optical repeater system. A principal-state transmission method, which can avoid PMD influence in coherent FDM common polarization control, has been proposed. In this scheme, FDM light is launched at one of the principal states in the fiber using two polarization controllers, located at both ends of the fiber. The feasibility of this scheme was confirmed through 2.5-Gb/s CPFSK, three-channel FDM transmission experiments. For a 150-km long fiber, a 700-GHz optical bandwidth can be used with the principal-state transmission method. This bandwidth is about three times wider than that for conventional common polarization control in a 150-km long fiber. The principal-state transmission method has been modified to apply to a long-span optical-repeater transmission system which includes optical isolators. In this method, small frequency modulation was added to the signal light to search for the principal state for the total transmission line. The modified method can avoid inter-symbol interference (ISI) degradation due to accumulated PMD in long-span optical fibers and optical components. Power-penalty-free operations were successfully demonstrated with up to one bit time PMD value in 5-Gb/s IM-DD, 1000-km transmission experiments. This method is expected to apply to a long-span undersea optical-repeater transmission system 相似文献