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11.
T Yamamura H Matsuzaki K Seo M Kimura T Shinagawa 《Canadian Metallurgical Quarterly》1998,28(11):1175-1178
We report herein the case of a 59-year-old woman who developed a local recurrence of rectal cancer which showed extremely rapid growth. The patient had undergone a curative low anterior resection with total mesoexcision, and was discharged on postoperative day 25 after an uneventful recovery. However, 2 months after the operation, she developed bleeding from the rectum during defecation, the quantity of which gradually increased. A colonoscopy performed during the fifth postoperative month revealed a circular tumor at the suture line. The tumor was unresectable because it had firmly invaded not only the sacrum, but also the right ureter. Despite the administration of 5-fluorouracil and leucovorin, the patient died of cancer 18 months after her initial surgery. Considering that local recurrence of rectal cancer does not usually occur within 1 year after surgery, this case is unusual because the local recurrence developed very early and showed extremely rapid growth, occupying the entire lumen of the rectum by the time it was detected by colonoscopy during the fifth postoperative month. 相似文献
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13.
Glucose administered to fasted rats caused a marked stimulation in hepatic cholesterogenesis and cholesterol 7 alpha-hydroxylation, and an increase in biliary excretion of cholesterol and total bile acids. The excretion of cholic acid was not incluenced during the first few hr after glucose administration, but was significantly increased after 5 hr. Chenodeoxycholic acid showed a similar change, but the increase was only ca. one tenth of that of cholic acid. The excretion of deoxycholic acid was markedly increased by 1 hr, but gradually decreased thereafter. Pretreatment with neomycin abolished the increase in deoxycholic acid by fasting and glucose administration. Other bile acid components showed no significant change. It thus was presumed that cholesterol endogenously synthesized in the liver was metabolized mainly to cholic acid. In contrast, exogenous cholesterol was metabolized mainly to chenodeoxycholic acid. During the period of the acute enhancement of cholic acid formation from the endogenous cholesterol, biliary excretion of deoxycholic acid was increased. This probably occurred through the depression of 7 alpha-rehydroxylation of deoxycholic acid, or through the enhancement of microbial formation of deoxycholic acid in the lumen, and through the increase of intestinal absorption. 相似文献
14.
Takashi Mitamura Hiroyuki Ogino Hidehiko Kobayashi Toshiyuki Mori Hiroshi Yamamura 《Journal of the American Ceramic Society》1993,76(8):2127-2128
Preparation of BaLa2 O4 , Ba3 ,Y4 O9 , Ba ,In2 O5 , and Ba3 Ga2 O6 powders and their sintering were investigated in Ar or air. These sintered bodies with perovskite-related structure were synthesized by reaction sintering, using mixed powders in the atomic ratios of Ba/La = 1, Ba/Y = 0.75, Ba/In = 1, and Ba/Ga = 1.5. The order-disorder transition temperatures of the BaLa2 O4 , Ba3 Y4 O9 , Ba2 In2 O5 , and Ba3 Ga2 O6 sintered bodies were 270°, 350°, 880°, and 123Oo C, respectively. It was found that the temperatures were influenced by the ionic radius of cations in B sites, and the transition temperatures decreased with increasing ionic radius. 相似文献
15.
Shinya Yamamura Akira Nagata Masato Tsuru Hitomi Tamura 《Simulation Modelling Practice and Theory》2011,19(1):30-46
We have proposed the concept of the virtual segment (VS), in which a global communication service is provided by combining a store–carry–forward scheme using vehicles with broadband wireless/wired network infrastructures along roads connected to the Internet. The VS can be a practical framework for non-real-time, asynchronous message transfer (especially for large messages) in a cost-effective manner. In this study, a critical implementation design issue, the message forward scheduling, in the VS approach is discussed and investigated through computer simulation by our developed VS simulator that has reflected the results of the field experiment for realistic performance evaluation. 相似文献
16.
OBJECTIVE: This paper introduces a robust, real-time system for detecting driver lane changes. Background: As intelligent transportation systems evolve to assist drivers in their intended behaviors, the systems have demonstrated a need for methods of inferring driver intentions and detecting intended maneuvers. METHOD: Using a "model tracing" methodology, our system simulates a set of possible driver intentions and their resulting behaviors using a simplification of a previously validated computational model of driver behavior. The system compares the model's simulated behavior with a driver's actual observed behavior and thus continually infers the driver's unobservable intentions from her or his observable actions. RESULTS: For data collected in a driving simulator, the system detects 82% of lane changes within 0.5 s of maneuver onset (assuming a 5% false alarm rate), 93% within 1 s, and 95% before the vehicle moves one fourth of the lane width laterally. For data collected from an instrumented vehicle, the system detects 61% within 0.5 s, 77% within 1 s, and 84% before the vehicle moves one-fourth of the lane width laterally. CONCLUSION: The model-tracing system is the first system to demonstrate high sample-by-sample accuracy at low false alarm rates as well as high accuracy over the course of a lane change with respect to time and lateral movement. APPLICATION: By providing robust real-time detection of driver lane changes, the system shows good promise for incorporation into the next generation of intelligent transportation systems. 相似文献
17.
Kiyotaka Yamamura Naoya Igarashi 《International Journal of Circuit Theory and Applications》2004,32(1):47-55
In this letter, an efficient algorithm is proposed for finding all solutions of non‐linear (not piecewise‐linear) resistive circuits. This algorithm is based on interval analysis, the dual simplex method, and the contraction methods. By numerical examples, it is shown that the proposed algorithm could find all solutions of systems of 500–700 non‐linear circuit equations in acceptable computation time. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
18.
Junya Hanaguri Harumasa Yokota Akifumi Kushiyama Sakura Kushiyama Masahisa Watanabe Satoru Yamagami Taiji Nagaoka 《International journal of molecular sciences》2022,23(3)
We investigated the effect of tofogliflozin, a sodium-dependent glucose cotransporter 2 inhibitor (SGLT2i), on retinal blood flow dysregulation, neural retinal dysfunction, and the impaired neurovascular coupling in type 2 diabetic mice. Tofogliflozin was added to mouse chow to deliver 5 mg/kg/day and 6-week-old mice were fed for 8 weeks. The longitudinal changes in the retinal neuronal function and blood flow responses to systemic hyperoxia and flicker stimulation were evaluated every 2 weeks in diabetic db/db mice that received tofogliflozin (n =6) or placebo (n = 6) from 8 to 14 weeks of age. We also evaluated glial activation and vascular endothelial growth factor (VEGF) expression by immunofluorescence. Tofogliflozin treatment caused a sustained decrease in blood glucose in db/db mice from 8 weeks of the treatment. In tofogliflozin-treated db/db mice, both responses improved from 8 to 14 weeks of age, compared with vehicle-treated diabetic mice. Subsequently, the electroretinography implicit time for the oscillatory potential was significantly improved in SGLT2i-treated db/db mice. The systemic tofogliflozin treatment prevented the activation of glial fibrillary acidic protein and VEGF protein expression, as detected by immunofluorescence. Our results suggest that glycemic control with tofogliflozin significantly improved the impaired retinal neurovascular coupling in type 2 diabetic mice with the inhibition of retinal glial activation. 相似文献
19.
Xiong Wei Wu Tomoo Yamamura Suguru Ohta Qi Xiu Zhang Fu Cong Lv Can Ming Liu Kenji Shirasaki Isamu Satoh Tatsuo Shikama Dan Lu Su Qin Liu 《Journal of Applied Electrochemistry》2011,41(10):1183-1190
The redox kinetics of VO2+/VO2 + and V3+/V2+ couples on a carbon paper (CP, HCP030 N, Shanghai Hesen, Ltd., China) electrode were investigated in terms of their standard rate constant (k 0) and reaction mechanism. The values determined for k 0 for VO2+ ?? VO2 + and V3+ ?? V2+ using the CP electrode are 1.0 × 10?3 and 1.1 × 10?3 cm s?1, respectively. The value of k 0 increases by one or two order(s) of magnitude compared with values obtained using electrodes composed of pyrolytic graphite and glassy carbon. The acceleration of the redox kinetics of vanadium ions is a result of the large surface area of the CP electrode. An inner-sphere mechanism for the reaction on the surface of the electrode is proposed. The kinetic features of vanadium redox reactions on the CP electrode reveal that CP is suitable for use as the electrodes in vanadium redox-flow batteries. 相似文献
20.
Mitsuyoshi Ishikawa Shohei Yamamura Yuzuru Takamura Koji Sode Eiichi Tamiya Masamitsu Tomiyama 《International Journal of Hydrogen Energy》2006
The development of a compact high-density microbial reactor for hydrogen production is described with possible implications to use as a portable bio-fuel cell system. To construct the compact bioreactor, mainly, the cell density and immobilization methods were optimized in this paper. The encapsulation of hydrogen producing bacterium, Escherichia coli strain MC13-4, in alginate gel beads provided approximately three-fold increase in hydrogen production in comparison with the free cell suspension. The immobilized cells (cell density; O.D. 100) and 500 mM glucose solution were packed into a 20 mL glass bottle that was connected to the fuel cell. This system has generated electricity of over 20 mW for 20 min. 相似文献