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排序方式: 共有1135条查询结果,搜索用时 15 毫秒
51.
Surgical treatment of Cronkhite-Canada syndrome associated with protein-losing enteropathy: report of a case 总被引:1,自引:0,他引:1
M Hanzawa N Yoshikawa T Tezuka K Konishi K Kaneko Y Akita K Mitamura A Tsunoda M Takada M Kusano 《Canadian Metallurgical Quarterly》1998,41(7):932-934
PURPOSE: The case of a patient with Cronkhite-Canada syndrome, who developed a protein-losing enteropathy, is reported. METHODS: After localization of the protein-losing region, a right colectomy was performed. RESULTS: Hypoproteinemia and ectodermal changes improved postoperatively. CONCLUSIONS: Surgery is an effective treatment for protein-losing enteropathy in Cronkhite-Canada syndrome. Ectodermal changes improve after correcting malnutrition. 相似文献
52.
53.
Inhibition by gluconic acid-1 : 5-lactone (gluconolactone) and phenyl alpha-glucoside of the hydrolysis of maltodextrin catalyzed by glucoamylase [EC 3.2.1.3] from Rhizopus niveus was investigated in relation to the subsite structure of the enzyme. Inhibition by gluconolactone was of the mixed type, whereas that by phenyl alpha-glucoside was purely competitive. These inhibition types were consistent with a theoretical prediction based on the assumption that gluconolactone and phenyl alpha-glucoside bind mainly to Subsites 1 and 2, respectively. The inhibitor constant of gluconolatone was determined to be 1.5 mM, which is in good agreement with the dissociation constant estimated by difference spectrophotometry (1.5 mM) (Ohnishi, M, et al. (1975) J. Biochem, 77, 695-703). 相似文献
54.
A mammalian genetic system to screen for small molecules capable of disrupting protein-protein interactions 总被引:2,自引:0,他引:2
Zhao HF Kiyota T Chowdhury S Purisima E Banville D Konishi Y Shen SH 《Analytical chemistry》2004,76(10):2922-2927
A mammalian two-hybrid system was developed for high-throughput screening of compounds that disrupt specific protein-protein interactions. The existing mammalian systems are unsatisfactory for drug screening due to nonregulated expression of interacting proteins. To construct a tightly regulated system, the tetracycline repressor was fused with the inhibitory KRAB domain as a suppressor. The binding of the suppressor to the tet operator entirely blocked expression of two interacting proteins. When both the inducer doxycycline and drugs were added to the culture, the reporter gene was either activated by interaction of the paired proteins with ineffective drugs or remained silent due to disruption of the protein interactions by the effective drugs. We demonstrate that interactions of the type I receptor for TGFbeta with FKBP12 and the epidermal growth factor receptor (EGFR) with p85 are effectively disrupted by FK506 and EGFR kinase inhibitor AG1478, respectively. The power of this system for drug screening was further demonstrated by rapid identification of inhibitors from a druglike library for the receptor kinases. 相似文献
55.
We have fabricated Nb3Ge microbridges, including those with variablethickness geometry, with submicrometer lengths, by means of plasma etching combined with lithographic techniques. The measuredI-V characteristic and the temperature variation of the critical current are consistent with that expected from the vortex concept. However, a deviation is observed in the microwave steps: the magnitude of the critical current oscillates with microwave power in a manner which agrees with an analog simulation based on the RSJ model. We have found a strong correlation between the bridge behavior and the film parametersT c and ρ n (normal resistivity). The critical current is reduced rapidly with a decrease inT c and an increase in ρ n , while in high-T c and low-ρ n bridges a linearI-V characteristic appears at low voltages. Taking into account the influence of pinning, we discuss the results in terms of vortex motion. 相似文献
56.
A classification technique using the neural networks has recently been developed. We apply a neural network of learning vector
quantization (LVQ) to classify remote-sensing data, including microwave and optical sensors, for the estimation of a rice-planted
area. The method has the capability of nonlinear discrimination, and the classification function is determined by learning.
The satellite data were observed before and after planting rice in 1999. Three sets of RADARSAT and one set of SPOT/HRV data
were used in Higashi–Hiroshima, Japan. Three RADARSAT images from April to June were used for this study. The LVQ classification
was applied the RADARSAT and SPOT to evaluate the estimate of the area of planted-rice. The results show that the true production
rate of the rice-planted area estimation of RADASAT by LVQ was approximately 60% compared with that of SPOT by LVQ. It is
shown that the present method is much better than the SAR image classification by the maximum likelihood method. 相似文献
57.
In real transportation environments for semi-conductor manufacturing, unexpected disturbances such as motion delays and/or sudden requests for transportation may cause collisions among AGVs increasing total transportation time. It is required to generate a collision-free routing for multiple automated guided vehicles (AGVs) within a few seconds. In this paper, we propose a distributed routing method under motion delay disturbance for multiple AGVs. The proposed method features a characteristic that each AGV subsystem derives its optimal route to minimize the sum of the transportation time and the penalties with respect to collision probability with other AGVs. The penalties reflect the collision probability distribution function for motion delay disturbances. The proposed method is applied to a routing problem for transportation in the semiconductor fabrication bay with 143 nodes and 20 AGVs. The computational results show that the total transportation time obtained by the proposed method is shorter than that of the conventional method. For dynamic transportation environments, an optimal timing for re-routing multiple AGVs under motion delay disturbance is systematically determined by the tradeoff relationship between the total computation time to derive a solution and the uncertainties for re-routings. Markov chain is used to represent uncertainty distribution for re-routings. The proposed method is implemented in an experimental transportation system with 51 nodes and 5 AGVs. The experimental results demonstrate that the proposed method is applicable to real transportation environments. 相似文献
58.
Hideki Kokame Kentaro Hirata Keiji Konishi Takehiro Mori 《International journal of control》2013,86(6):537-546
Supposing a non-linear system is subjected to parametric uncertainties, the present paper aims at stabilizing its unstable steady states. A distinctive feature of the problem is that exact information about the steady state is unavailable. To cope with the difficulty, we have examined the applicability of the state difference feedback which uses the difference between the present state x(t) and the past state x(t-T). A rigorous stability analysis has been executed for the case where state deviations are controllable by a single input variable. The stability analysis has led to a favourable conclusion that if the number of unstable modes is just two, and if they are not associated with the origin in the complex plane, we are always able to find a controller which stabilizes the deviations from the unknown steady state. Design process is illustrated by using two kinds of pendulum systems. 相似文献
59.
Hiroshi Kajino Hiromi Arai Hisashi Kashima 《Data mining and knowledge discovery》2014,28(5-6):1314-1335
This paper proposes a crowdsourcing quality control method with worker-privacy preservation. Crowdsourcing allows us to outsource tasks to a number of workers. The results of tasks obtained in crowdsourcing are often low-quality due to the difference in the degree of skill. Therefore, we need quality control methods to estimate reliable results from low-quality results. In this paper, we point out privacy problems of workers in crowdsourcing. Personal information of workers can be inferred from the results provided by each worker. To formulate and to address the privacy problems, we define a worker-private quality control problem, a variation of the quality control problem that preserves privacy of workers. We propose a worker-private latent class protocol where a requester can estimate the true results with worker privacy preserved. The key ideas are decentralization of computation and introduction of secure computation. We theoretically guarantee the security of the proposed protocol and experimentally examine the computational efficiency and accuracy. 相似文献
60.
Yasuhiro Konishi Takeshi TsukiyamaKaori Ohno Norizoh SaitohToshiyuki Nomura Shinsuke Nagamine 《Hydrometallurgy》2006
Microbial reduction and intracellular precipitation of gold was achieved at 25 °C and pH 7 by using the mesophilic anaerobic bacterium Shewanella algae with H2 as the electron donor. The reductive precipitation of gold by S. algae was a fast process: 0.1–1 mol/m3 AuCl4− ions were completely reduced to insoluble gold within 30 min. The biogenic precipitates were crystalline gold nanoparticles of 10–20 nm present in the periplasmic space. The reducing power of S. algae at 3.2 × 1015 cells/m3 and 25 °C was comparable to that of aqueous citric acid solution (chemical reductant) at 20 mol/m3 and 50 °C. The intracellular recovery of gold is potentially attractive as an environmentally friendly alternative to conventional methods. 相似文献