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991.
992.
OBJECTIVE: To determine the serum levels of soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble E-selectin (sE-selectin) in patients with systemic sclerosis (SSc). METHOD: Serum samples from 80 patients with SSc and 20 healthy control subjects were examined by a sensitive enzyme-linked immunosorbent assay. RESULTS: The serum levels of sVCAM-1 and sE-selectin were significantly higher in the patients with SSc than in the healthy controls. The serum levels of sVCAM-1 were correlated with the presence of pulmonary fibrosis, joint involvement and elevated erythrocyte sedimentation rate levels. The serum levels of sE-selectin were correlated with the presence of pulmonary fibrosis. CONCLUSION: These results suggest that endothelial activation is involved in the development of this disease. 相似文献
993.
Exact optimization for Markov random fields with convex priors 总被引:4,自引:0,他引:4
We introduce a method to solve exactly a first order Markov random field optimization problem in more generality than was previously possible. The MRF has a prior term that is convex in terms of a linearly ordered label set. The method maps the problem into a minimum-cut problem for a directed graph, for which a globally optimal solution can be found in polynomial time. The convexity of the prior function in the energy is shown to be necessary and sufficient for the applicability of the method. 相似文献
994.
T Ishikawa N Tanaka K Houkin S Kuroda H Abe K Mitsumori 《Canadian Metallurgical Quarterly》1998,14(8):366-371
Thirteen pediatric patients (ages 4-13 years) who underwent surgical treatment were examined regarding their rCBF in the preoperative periods. The postoperative rCBF was measured 39 times in these 13 patients. Thirteen healthy normal subjects (ages from 6 to 21 years) were also examined. The rCBF in the operculum and in the frontal, parietal, and occipital lobes was measured with 133Xe inhalation method and single photon emission computed tomography. In the parietal and occipital lobes, the preoperative rCBF had a negative and significant correlation with their ages, but not in the operculum or frontal lobe. However, subsequent to the surgical treatment, the rCBF increased significantly in the patients 5 years old or less, and then post-operative rCBF values had significant negative correlations with age in each region. 相似文献
995.
Takashi Yabe Takayuki Aoki Gyo Sakaguchi Pei-Yuan Wang Takeo Ishikawa 《Computers & Fluids》1991,19(3-4):421-431
A new universal solver is proposed for general hyperbolic equations; multi-dimensional, linear and nonlinear equations with dissipative and dispersive terms. The scheme uses piecewise cubic polynomial interpolation inside meshes. The physical quantity and its spatial derivative are advanced in time according to the given equation. The scheme not only describes a sharp discontinuity with only one mesh but also reproduces the traveling wave train in the dispersive media. The extension to higher dimensions is straightforward. 相似文献
996.
Transesterification of oil by fatty acid-modified lipase 总被引:2,自引:0,他引:2
Mototake Murakami Yoshihiro Kawasaki Masami Kawanari Hideo Okai 《Journal of the American Oil Chemists' Society》1993,70(6):571-574
Fatty acid was covalently attached to lipase (EC 3.1.1.3.) fromPhycomyces nites, yielding a modified lipase of higher specific activity in hydrolytic and synthetic reactions in organic solvents. Attached
long-chain fatty acids solubilized the lipase in organic solvent and, therefore, promotion of dispersibility in organic solvent
resulted in much higher reactivity. The initial rate of transesterification by modified lipase was almost 40 times that of
native lipase in organic solvent. The specificities and selectivity of the modified lipase depended on the kind of attached
fatty acid. 相似文献
997.
Kamite K. Sudo H. Yano M. Ishikawa H. Imai H. 《Quantum Electronics, IEEE Journal of》1987,23(6):1054-1058
A bandwidth of 13 GHz has been attained in a 1.3 μm DFB laser at 25 °C. A mesa structure was introduced to reduce the parasitic capacitance and the lasing wavelength was detuned from the gain peak to increase the differential gain. This bandwidth is the widest so far reported in 1.3 μm DFB lasers. 相似文献
998.
Martinez Joe L. Jr.; Ishikawa Koichi; Liang K. C.; Jensen Robert A.; Bennett Cathy; Sternberg Debra B.; McGaugh James L. 《Canadian Metallurgical Quarterly》1983,97(6):962
In Exp I, an .82 mg/kg dose of 4-OH amphetamine hydrobromide (AMP) administered ip immediately following training in a 1-way active avoidance task enhanced retention performance of male ARS Sprague-Dawley rats measured 24 hrs later. In contrast, AMP in a dose range of .41–2.64 mg/kg, ip, did not affect retention of a swim escape task (Exp II). The behaviorally active dose of .82 mg/kg decreased dopamine concentrations in the amygdala and hippocampus. A dose of 8.2 mg/kg administered ip to naive untrained Ss (Exp III) decreased concentrations of norepinephrine measured in the amygdala, cortex, hippocampus, hypothalamus, and midbrain; decreased concentrations of dopamine in the amygdala, cortex, hippocampus, and striatum; and significantly reduced concentrations of norepinephrine and epinephrine in the adrenal medulla. In addition, because the integrity of the adrenal medulla is necessary for the enhancing action of AMP and because AMP reduces concentrations of catecholamines in the brain and adrenal medulla, it is possible that this drug affects retention performance by a dual action on the brain and the adrenal medulla. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Kabuo H. Okamoto M. Tanaka I. Yasoshima H. Marui S. Yamasaki M. Sugimura T. Ueda K. Ishikawa T. Suzuki H. Asahi R. 《Solid-State Circuits, IEEE Journal of》1996,31(4):494-503
This paper describes a 16-b fixed point digital signal processor (DSP), especially its multiply-accumulate (MAC) unit, memories, and instruction set. By adopting a redundant binary multiplier and a variable pipeline structure, this DSP's MAC unit, compared to a conventional MAC unit, consumes about 15% less power and operates 24% faster. Furthermore, its double-speed MAC mechanism can realize twice the performance of a single MAC operation while consuming only 69% more power. By being able to more finely control which portions of memory are activated, the data ROM and data RAM's precharge current was reduced to about 1/8 of the conventional ROM and RAMs. We redesigned the instruction set and reduced its width from 32 b to 24 b based on the analysis of data generated by simulating an application program on our previous DSP. The reduction in instruction width made our on-chip instruction memory size 33% smaller than the previous one. This chip is fabricated with a 0.5-μm double-metal-layer CMOS process and achieves 80-MOPS-peak double speed multiply-accumulate performance 相似文献
1000.
Ishikawa J 《Applied optics》1995,34(27):6095-6098
Radiation heating enables fast temperature control. I applied radiation heating to the oscillation frequency control of an internal-mirror He-Ne laser. The laser system has a fast frequency response, and its oscillation frequency is offset-locked in an iodine-stabilized He-Ne laser by a phase-lock loop circuit. The frequency discrepancy σ between the master and the slave lasers is less than 10(-13) with a 100-s gate time. 相似文献