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11.
S Murakami H Yokomizo S Matsushita M Ogawa Y Nishimura 《Canadian Metallurgical Quarterly》1996,49(3):149-153
We investigated retrospectively 132 cases of open wedge high tibial osteotomy using an external fixation device, concentrating on the rate of neurological complications. One group of patients underwent surgery according to the conventional technique (n = 89). The rate of transient neurological complications was 15.7%; 7 months after surgery the rate of persistent deficits was 12.4%. For the second group (n = 43) a modified surgical technique was used that lowered the complication rate significantly (transient deficits 14%, persistent deficits 4.7%). In the modified technique the osteotomy is not performed in the conventional way using an oscillating saw but through consecutive drill holes of increasing diameter followed by osteoclasis. The lower complication rate in the second group is mainly due to the less extensive approach that leads to a smaller number of postoperative tibialis anterior syndromes (type B lesion). No differences were found with type C lesions (extension deficit of D1). No complete peroneal nerve palsy (type A) occurred in either group. We conclude that the reduction of neurological complications in group 2 is related to the less extensive approach of the proposed technique. 相似文献
12.
Jamalipour A. Katayama M. Yamazato T. Ogawa A. 《Selected Areas in Communications, IEEE Journal on》1996,14(9):1748-1757
A transmit permission control method for improving the throughput characteristics of a low Earth orbit (LEO) satellite communication system employing spread-slotted ALOHA multiple-access scheme is proposed. Both nonfading and fading satellite links are considered. The basic idea of the proposed scheme is to decrease the level of interference at each satellite and, hence, to increase the probability of packet success, by prohibiting the packet transmission from the users with relatively high propagation loss to their connecting satellites. It is shown that the method has the ability to improve the throughput performance in heavy traffic loads and the peak value of the throughput, significantly. It is also shown that the average delay performance of the system employing the proposed scheme is superior to that of the conventional system at heavy traffic loads 相似文献
13.
Y Takayama M Sugishita T Kido M Ogawa H Fukuyama I Akiguchi 《Canadian Metallurgical Quarterly》1994,57(5):652-654
A right-handed patient with a haematoma in the left pulvinar showed impaired stereoacuity. In contrast with previous reports, he did not show peripheral visual extinction or prolonged reaction times for targets on the side contralateral to the lesion. 相似文献
14.
The gamma-ray-induced crosslinking of polyacrylamide was carried out under various conditions. The molecular weight of the polymer before inrradiation was found to be the most important factor for crosslinking. When polymers have low molecular weights such as 80,000, the intensity of radiation, the external pressure applied, and the water content of the polymer powder became important for crosslinking. Although the polycrylamide hydrogel can be obtained directly by irradiating the monomer, it was obtained more conveniently by the irradiation of monomer—polymer mixtures. The hydrogels obtained by the radiation with a dose of over 50 kgray, absorb water by 1000–1500 wt %. 相似文献
15.
Computationally very expensive dynamic-programming matching of data sequences has been directly implemented in a fully-parallel-architecture VLSI chip. The circuit operates as digital logic in the signal domain, while analog processing is carried out in the time domain based on the delay-encoding-logic scheme. As a result, a high-speed low-power best-match-sequence search has been established with a small chip area. The typical matching time of 80 ns with the power dissipation of 2 mW has been demonstrated with fabricated prototype chips. 相似文献
16.
G Han T Chen J Yang J Dai R Xu Y Zhang J Okano R Yui H Nakajima T Hamasaki 《Canadian Metallurgical Quarterly》1996,21(10):591-4, 639
This paper reports the GC determination of 20 organochlorine pesticides in Chinese drugs Flos Ionicerae and Moluodan etc by the present method of Japan for determinaing pesticide residues. The results suggest that except Folium Isatidis, Radix Codonopsis and Sanqi Pian all accord with the for provisions pesticide residues in Japanese foodstuffs. 相似文献
17.
M Tanji F Iwaya T Igari T Ogawa K Takahashi S Hoshino 《Canadian Metallurgical Quarterly》1996,44(12):2146-2150
This report describes a 5-year-old girl with congenital tricuspid regurgitation associated with an atrial septal defect and peripheral pulmonary stenosis. The girl was diagnosed with the heart murmur at birth and recently developed the cardiomegaly. Cardiac echocardiography and catheterization showed severe tricuspid regurgitation, an atrial septal defect of the secundum type and peripheral pulmonary stenosis. In the operative findings, the tricuspid annulus was dilated to 33 mm in diameter, and leaflets were attached normally to the antomic annulus. There was a large cleft of the anterior leaflet of the tricuspid valve. Suture of the cleft and annuloplasty of the tricuspid valve, suture closure of the atrial septal defect and patch dilatation of peripheral pulmonary stenosis were successfully performed. Including this case, 19 other cases with congenital tricuspid regurgitation undergoing surgery were reported to date. 相似文献
18.
The effect of plasma elongation on the second‐stable spherical tokamak (ST) was numerically studied using the experimentally measured pressure and current profiles of ultrahigh‐beta STs. The maximum beta of ST over 50% was obtained in the TS‐3 ST/CT experiment by applying an external toroidal field to an FRC. It was found that the marginal beta for the ballooning instability increased with the plasma elongation κ of ST. The elongated STs with κ > 2 have the magnetic shear (S)–pressure gradient (α) profiles located in the second‐stable regime for the ballooning mode and the stability margin increased with κ. The close relation between the absolute minimum‐B profile and the second stability was documented. The effect of elongation on maximum beta was observed to saturate when κ exceed 3, indicating that the optimized elongation for high‐beta STs is located around 2 < κ < 3. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(4): 1–6, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20132 相似文献
19.
Hida H. Tsukada Y. Ogawa Y. Toyoshima H. Fujii M. Shibahara K. Kohno M. Nozaki T. 《Electron Devices, IEEE Transactions on》1989,36(10):2223-2230
The authors describe a novel design concept for enhancement (E) and depletion (D) mode FET formation using i-AlGaAs/n-GaAs doped-channel hetero-MISFET (DMT) and a novel self-aligned gate process technology for submicrometer-gate DMT-LSIs based on E/D logic gates. 0.5-μm gate E-DMTs (D-DMTs) with a lightly doped drain (LDD) structure show an average V t of 0.18 (-0.46) V, a V t standard deviation of 22.6 (24.9) mV, and a maximum transconductance of 450 (300) mS/mm. The V t shift is less than 50 mV with a decrease in gate length down to 0.5 μm. The gate forward turn-on voltage V f is more than 0.9 V, i.e. about 1.6 times that for MESFETs. This superiority in V f, preserved in the high-temperature range, leads to an improvement in noise margin tolerance by a factor of three. In addition, 31-stage ring oscillators operate with a power consumption of 20 (1.0) mW/gate and a propagation delay of 4.8 (14.5) ps/gate. Circuit simulation based on the experimental data predicts 140 ps/gate and 1 mW/gate for DMT direct-coupled FET logic circuits under standard loading conditions. DMTs and the technology developed here are very attractive for realizing low-power and/or high speed LSIs 相似文献
20.
JA Gogos M Morgan V Luine M Santha S Ogawa D Pfaff M Karayiorgou 《Canadian Metallurgical Quarterly》1998,95(17):9991-9996
Catechol-O-methyltransferase (COMT) is one of the major mammalian enzymes involved in the metabolic degradation of catecholamines and is considered a candidate for several psychiatric disorders and symptoms, including the psychopathology associated with the 22q11 microdeletion syndrome. By means of homologous recombination in embryonic stem cells, a strain of mice in which the gene encoding the COMT enzyme has been disrupted was produced. The basal concentrations of brain catecholamines were measured in the striatum, frontal cortex, and hypothalamus of adult male and female mutants. Locomotor activity, anxiety-like behaviors, sensorimotor gating, and aggressive behavior also were analyzed. Mutant mice demonstrated sexually dimorphic and region-specific changes of dopamine levels, notably in the frontal cortex. In addition, homozygous COMT-deficient female (but not male) mice displayed impairment in emotional reactivity in the dark/light exploratory model of anxiety. Furthermore, heterozygous COMT-deficient male mice exhibited increased aggressive behavior. Our results provide conclusive evidence for an important sex- and region-specific contribution of COMT in the maintenance of steady-state levels of catecholamines in the brain and suggest a role for COMT in some aspects of emotional and social behavior in mice. 相似文献