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71.
72.
H Murata S Kawano S Tsuji M Tsujii H Sawaoka H Iijima N Kawai M Hori 《Canadian Metallurgical Quarterly》1998,93(11):2102-2105
OBJECTIVE: The accuracy of the PyloriTek test (a 1-h rapid urease test) used after eradication therapy of Helicobacter pylori (H. pylori) has not been well clarified. This study was done to evaluate the accuracy of the PyloriTek test results for cases with and without eradication therapy, using culture and histology as gold standard methods, and to establish the suitable timing of the PyloriTek test after eradication treatment. METHODS: One hundred sixty-three patients undergoing upper endoscopy were randomly selected; 100 patients had not received eradication therapy and 63 had. Three biopsy specimens each were obtained from the gastric antrum and the body for examination by PyloriTek, culture, and histology. The absence of H. pylori was established with negative results from both culture and histology. RESULTS: In cases without eradication therapy, PyloriTek, correctly identified 66 of 67 H. pylori-positive cases and 30 of 33 H. pylori-negative cases, yielding 98.5% sensitivity and 90.9% specificity. In cases with eradication therapy, PyloriTek gave correct diagnoses in 10 of 17 H. pylori-positive cases and in 45 of 46 H. pylori-negative cases, for 58.8% sensitivity and 97.8% specificity. However, when PyloriTek was used more than 4 months after the end of eradication therapy, both the sensitivity and the specificity increased to 100%. CONCLUSION: Considering time and cost, the use of PyloriTek alone may be satisfactory for detecting H. pylori infection in cases without eradication therapy. When patients are examined more than 4 months after intervention, the use of PyloriTek alone may be sufficient for correctly diagnosing H. pylori infections. 相似文献
73.
We consider the backing-up control of a vehicle with triple trailers using a model-based fuzzy-control methodology. First, the vehicle model is represented by a Takagi-Sugeno fuzzy model. Then, we employ the so-called "parallel distributed compensation" design to arrive at a controller that guarantees the stability of the closed-loop system consisted of the fuzzy model and controller. The control-design problem is cast in terms of linear matrix inequalities (LMIs). In addition to stability, the control performance considerations such as decay rate, constraints on input and output, and disturbance rejection are incorporated in the LMI conditions. In application to the vehicle with triple trailers setup, we utilize these LMI conditions to explicitly avoid the saturation of the steering angle and the jackknife phenomenon in the control design. Both simulation and experimental results are presented. Our results demonstrate that the fuzzy controller effectively achieves the backing-up control of the vehicle with triple trailers while avoiding the saturation of the actuator and "jackknife" phenomenon. 相似文献
74.
Oodo Masayuki Miura Ryu Hori Teruhisa Morisaki Takayuki Kashiki Kanshiro Suzuki Mikio 《Wireless Personal Communications》2002,23(1):3-14
In the World Radiocommunication Conference 2000 (WRC-2000), use of the 31 GHzand 28 GHz bands was permitted for the fixed service (FS) by using highaltitude platform stations (HAPS) in some countries. This paper examines thesharing and compatibility of the HAPS-based FS with the other services usingthe same and adjacent frequency bands and establishes the conditions of thecoexistence with those services. Feasibility of dynamic channel assignment(DCA) scheme among the different communication systems to facilitate thecoexistence is also studied. 相似文献
75.
Various discrete-time models of a continuous-time system are given an interpretation in terms of the system structures and the hold device. This concept provides a novel perspective of various discrete-time models and a simple way to understand the relationships which exist among those models, but which are not easily visualized without the proposed interpretation. This interpretation of discrete-time models also allows the creation of new types of models. Tables of discrete-time models, including the newly developed ones, are provided 相似文献
76.
Deep submicrometer CMOSFETs with re-annealed nitride-oxide gate dielectrics have been demonstrated to satisfy 3.3-V operation, unlike conventional oxide FETs. The 1/4-μm re-annealed nitrided-oxide CMOS devices achieve (1) an improved saturation transconductance g m of ~250 μS/μm for n-FETs together with acceptably small degradation in p-FET g m resulting in a CMOS gate delay time of 55 ps/stage comparable or superior to the device/circuit performance of oxide FETs, and (2) device lifetimes improved by ~100 times to exceed 10 years with respect to both ON- and OFF-state hot-carrier reliability for n-FETs as well as gate-dielectric integrity together with unchanged p-FET hot-carrier reliability, all at 3.3-V operation. To achieve these CMOS performance/reliability improvements, both a light nitridation and subsequent re-annealing in O 2 (reoxidation) or in N2 (inert-annealing) are found to be crucial 相似文献
77.
Several kinds of fusion proteins between human aldolases A andB were prepared by recombinant DNA technology and their enzymicproperties were examined. AB chimeras, which have aldolase Aat the N-terminal region and aldolase B at the C-terminal region,were scarcely obtained, while BA chimeras were abundant (Kitajimaet al., (1990), J. Biol. Chem., 265, 17493-17498). All the BABchimeras, aldolase A fragments inserted in aldolase B, showedactivity assignable to aldolase B type, which imply an essentialrole of Tyr residue at the C-terminus of aldolase A in the bindingof fructose-l,6-bisphosphate (Fni-1,6-P2). BAB chimeras alsoshowed reactivity to effectors such as fructose-2,6-bisphosphate(Fru-2,6-P2) and pyridoxal 5-phosphate (PLP), in a similar mannerto aldolase B. BAB108 has a similarity to the BA108 chimera,but acts differently from other BAB chimeras, suggesting thatits structure around active site looks like that of aldolaseA 相似文献
78.
Two-branch vertical space diversity (V-SD) and horizontal space diversity (H-SD) antenna arrangements mounted on a metal pole to illuminate a street cell are investigated. Measurement results taken in a Japanese suburban area are also presented. These results clarify the required arrangements for both V-SD and H-SD configurations. Measured results show that the optimum arrangement of the H-SD configuration depends on the diameter of the pole on which the antennas are mounted 相似文献
79.
T Oka T Nakatsu S Kusachi Y Tominaga S Toyonaga K Hori 《Canadian Metallurgical Quarterly》1997,61(8):719-723
A 54-year-old woman was admitted to our hospital because of a heart murmur without subjective symptoms. Angiography disclosed an enlarged right coronary artery and flow drainage into the left ventricle, ie, a large right coronary artery-left ventricle fistula. Analysis of pulsed Doppler studies and cineangiograms indicated considerable capacitance of this fistula owing to Windkessel action, which attenuated volume overload on the left ventricle. The features in this case suggest that evaluation of fistula hemodynamics is important in determining the overload on the ventricle through the fistula. 相似文献
80.
Deep-submicrometer large-angle-tilt implanted drain (LATID) technology is described. It is found by Monte Carlo process simulation and SIMS measurements that a sufficiently long n- region can be formed under the gate by taking advantage of large-angle-tilt implant and successfully without ion channeling by taking care of the implant direction. A design that offsets the n+ implant by sidewall spacers to suppress the n+-gate overlap to zero while keeping the n- region fully overlapped with the gate is found to be crucial for improved performance and reliability. The device performance, such as current drivability and short-channel effects, is described, and the circuit speed is investigated. Hot-carrier effects such as lateral electric field and device lifetime over a wide range of drain structures are also investigated. The tradeoff between device performance and hot-carrier reliability in deep-submicrometer LATID FETs is discussed 相似文献