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排序方式: 共有805条查询结果,搜索用时 15 毫秒
91.
92.
T Yokoyama K Sugiyama S Nishizawa T Tanaka N Yokota S Ohta K Uemura 《Canadian Metallurgical Quarterly》1998,140(12):1287-90; discussion 1291
The neural activity pattern of the subthalmic nucleus (STN) was investigated in five patients with Parkinson's disease who were scheduled for electrode implantation for chronic stimulation of the STN. The initial target was placed 8 mm or 10 mm lateral to the midline, 3 mm to 4 mm posterior to the midcommissural point, and 5 mm to 6 mm below the intercommissural (AC-PC) line. The STN was identified by semi-microelectrode recordings with a trajectory moving laterally in 2-mm steps. The amplitudes of multi-unit activities were relatively low at depths from 8 mm to 5 mm above and from 1 mm to 4 mm below the target, while those 4 mm to 0 mm above the target were significantly higher than at the other sites (ANOVA, Fisher's test, p < 0.05), with the highest amplitude at 2 mm above the target (91.0 +/- 23.3 mu v, n = 15). In the mediolateral direction, amplitudes were relatively higher in the lateral portion, and amplitudes at 14 mm lateral to the midline were significantly higher than at the other sites (ANOVA, Fisher's test, p < 0.05). The target for chronic electrical stimulation was determined to be at the midpoint of the hyperactive STN, i.e., 12 mm lateral to the midline in three patients and 13 mm lateral in two patients. Movement-related neural activity was observed at 5 sites, i.e., 3 sites responded to passive movement of the contralateral wrist and 2 sites to passive knee and/or ankle movement. In conclusion, our data show that the lateral part of the STN is hyperactive in PD, and recordings of neural activities contributed greatly to identifying the STN and determining the target for chronic stimulation within it. 相似文献
93.
M Uemura T Tsujii E Kikuchi H Fukui N Tsukamoto M Matsumura M Fujimoto M Koizumi A Takaya H Kojima Y Ishii S Okamoto 《Canadian Metallurgical Quarterly》1998,33(8):860-866
We describe a surgical technique for replacing the hip joint capsule using synthetic mesh after oncological resections of the proximal femur that resulted in gross intraoperative instability of the prosthetic reconstruction. The results of its use in 13 patients, 6 of whom also had pelvic resections, are described. These patients were selected from a total group of 88 patients undergoing proximal femoral replacement, 75 of whom did not require capsular replacement (none of these 75 patients have experienced dislocation). In the group requiring capsular reconstruction, 1 of 4 patients with bipolar hemiarthroplasty and 4 of 9 patients with total hip replacements experienced dislocation after operation. Of the dislocated total hip replacements, 1 remains chronically dislocated, and 3 were successfully stabilized by open reduction with further capsular augmentation. Given that the resections involved removal of most of the soft tissues stabilizing the hip joint, we believe that the technique of capsular reconstruction is useful in this difficult group of patients. 相似文献
94.
Kosaka H. Kurihara K. Uemura A. Yoshikawa T. Ogura I. Numai T. Sugimoto M. Kasahara K. 《Photonics Technology Letters, IEEE》1994,6(3):323-325
Vertical-to-surface transmission electrophotonic devices with a vertical-cavity are described. The individually accessed 12×4 arrays are characterized and demonstrated to have uniform room-temperature continuous-wave operating characteristics for a threshold current of ~2.8±0.15 mA and a slope efficiency of ~0.18±0.012 W/A with a single transverse mode. Both low threshold and high efficiency with 5% and 7% deviation, respectively, are achieved simultaneously. These devices can be used to constructing two-dimensional massively parallel optical interconnections 相似文献
95.
Shigeki Toyama 《Desalination》1977,20(1-3)
The test module plant which is a quarter fragment of the conceptually designed, desalting plant with capacity of 100,000 m3/d has been operated as an activity of the national project in Japan. The type of the desalting plant is a high flow rate long tube multistage flash evaporator which is designed on the basis of the result achieved by the systematic research of the project. Where, condensing heat transfer tubes of length 33.6 m were successfully installed, and the reinforced concrete shell in the heat rejecting section is practiced without any trouble as a corrosion free vessel. The data acquisition system for the test module deals with 600 data which are classified into the total process, the concrete shell, the test sections and the pretreatment process. In the test section, temperature distribution of the brine flow is intended to measure at an accuracy of the order of 0.01°C. The paper describes these results on the basis of the recent information, and gives a scope for expecting effect on the progress of desalination technology. 相似文献
96.
97.
M Nakayama Y Kobayashi Y Oshima N Uemura E Shindo K Tajika K Yanagisawa S Takahashi S Irie A Tojo 《Canadian Metallurgical Quarterly》1995,36(7):703-706
A 64-year-old woman with multiple myeloma, IgG lambda type Durie-Salmon Stage II, was admitted because of gradually developing anemia and increased blasts with abnormal karyotype in her bone marrow after 10 years of treatment. The chromosomal analysis showed 44, XX, del(5q), del(7q), -9, add(12p), -21, typical of secondary MDS due to the cumulative alkylating agents. Thrombocytosis concomitantly occurred with emergence of chromosomal abnormality, but the serum interleukin 6 level was not elevated, which suggested that it was related to development of secondary MDS. 相似文献
98.
Shigeki Iyoki Masahito Nakanishi Hiroshi Yoshida Tohru Okuda Tadashi Uemura 《International Journal of Refrigeration》1993,16(4)
The thermodynamic properties (solubility, vapour pressure, density, viscosity, heat capacity and heat of mixing) of the H2O + CH3OH + LiBr + ZnCl2 (9:1 H2O:CH3OH and 1:1 LiBr:ZnCl2 by mass) system using H2O + CH3OH as the working media and LiBr + ZnCl2 as the absorbents were measured. The solubility data were obtained in the temperature range from 270.35 to 389.55 K. The measurements of vapour pressure, density, viscosity and heat capacity were carried out at various temperatures and absorbent concentrations. The differential heat of dilution and differential heat of solution at 298.15 K were measured for solutionw with absorbent concentrations from 0 to 75.2 wt%. The integral heat of mixing data at 298.15 K were obtained from both sets of experimental data. The integral heats of mixing for this quaternary system showed exothermic behaviour. The vapour pressure data were correlated with an Antoine-type equation. An empirical formula for the heat capacity was obtained from experimental data. The experimental data for the basic thermodynamic properties of this quaternary system were compared with those of the basic H2O + LiBr system. 相似文献
99.
Shigeki Shibayama Takeo Kakuta Nobuyoshi Miyazaki Haruo Yokota Kunio Murakami 《New Generation Computing》1984,2(2):131-155
This paper describes the basic concepts, design and implementation decisions, standpoints and significance of the database machine Delta in the scope of Japan’s Fifth Generation Computer Project. Delta is planned to be operational in 1985 for researchers’ use as a backend database machine for logic programming software development. Delta is basically a relational database machine system. It combines hardware facilities for efficient relational database operations, which are typically represented by relational algebra, and software which deals with hardware control and actual database management requirements. Notable features include attribute-based internal schema in accordance with the characteristics found in the relation access from logic programming environment. This is also useful for the hardware relational algebra manipulation algorithm based on merge-sorting of attributes by hardware and a large capacity Semiconductor Disk for fast access to databases. Various implementation decisions of database management requirements are made in this novel system configuration, which will be meaningful to give an example for constructing a hardware and software combination of a relational database machine. Delta is in the stage between detailed design and implementation. 相似文献
100.
Fatigue behaviour was investigated for low-strength silica fibres on which macroscopic flaws were forcibly introduced by abrading. Crack growth in silica glass was also examined on the CT specimen. Stable crack growth parameters, obtained from the static and dynamic fatigue tests for abraded fibres, were determined to be about 40 which is equal to that obtained from the CT specimen, indicating that the crack growth process in abraded fibres is quite the same as in the CT specimen. This leads to the conclusion that, for the optical fibre, the allowable stress condition wherein no breaks occur is given on the basis of some basic fracture mechanics parameters obtained from the CT specimen. 相似文献