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排序方式: 共有1482条查询结果,搜索用时 46 毫秒
941.
The cytosolic extract from Drosophila heads was separated using anion-exchange column chromatography. Two types of cAMP-dependent protein kinase (PKA), type I and type II, were detected, and type II PKA was found to be a major isozyme. The regulatory subunit of type II PKA (RII) was purified, and only one isoform was observed. The purified protein had an apparent molecular mass of 51 kDa on SDS gel electrophoresis. Partial amino acid sequences of the protein were almost identical with the RII alpha subunit of human. Since PKA has been implicated to be especially important for learning and memory in Drosophila, the RII subunit may play an essential role in the regulation of neuronal activity in the brain of Drosophila, and possibly in human. 相似文献
942.
943.
This paper presents a new method to measure cyclic strain with no contact using metal foil gauges assisted by the laser speckle method. When aluminium foil is pasted on a specimen and the specimen is loaded cyclically, slip bands are produced on the foil surface. There is a fixed relation between density of the slip bands and the strain amplitude or loading cycles depending on the foil material. Thus the fatigue strain of the base metal can be estimated by observing the surface change of the metal foil by the slip bands at a constant number of loading cycles. The method presented in this paper is intended to make a non-contacting strain measurement by the application of the laser speckle technique for the detection of the surface change. This method is based on observation of the changes in a laser speckle pattern depending on the surface roughness and surface property changes of the foil caused by fatigue. The laser speckle pattern can be analysed automatically and quantitatively using an image processing system. 相似文献
944.
KADONO Yasuo 《中国电子科技》2004,2(3)
Many corporate senior managers have not been fully convinced of successful IT management over a period of decades. In order to clarify the mechanism of IT management in companies, we conducted the surveys on IT management in 2000 and 2002. Through the surveys and analyses, we found the causal structure in IT management, developed "IT Management Effectiveness" as a new measurement tool, published ranking lists of high scored companies, and analyzed characteristics of industry/sizes of respondents and so on. Based on the surveys and researches so far, we would suggest future works, such as comparison of Japanese companies with overseas companies, time series analyses. 相似文献
945.
M Mazzucato P Spessotto A Masotti L De Appollonia MR Cozzi A Yoshioka R Perris A Colombatti L De Marco 《Canadian Metallurgical Quarterly》1999,274(5):3033-3041
We have identified type VI collagen (Col VI) as a primary subendothelial extracellular matrix component responsible for von Willebrand factor (vWF)-dependent platelet adhesion and aggregation under high tensile strength. Intact tetrameric Col VI was the form of the collagen found to be capable of promoting vWF-mediated platelet adhesion/aggregation under this shear condition, whereas removal of the predominant portion of the terminal globules by pepsin treatment abrogated its activity. The inability of the pepsin-digested Col VI to support any platelet interaction at high flow was because of the failure of the A3(vWF) domain to bind to this form of collagen, suggesting a stringent requirement of a tridimensional conformation or of intactness of its macromolecular structure. In contrast, the A1(vWF) domain bound to both intact and pepsin-digested Col VI tetramers but, in accordance with the cooperating function of the two vWF domains, failed to support platelet adhesion/aggregation under high shear onto Col VI by itself. The putative A1(vWF) binding site resided within the A7(VI) module (residues 413-613) of the globular amino-terminal portion of the alpha3(VI) chain. Soluble recombinant A7(VI) polypeptide strongly perturbed the vWF-mediated platelet adhesion to Col VI under high shear rates, without affecting the binding of the vWF platelet receptor glycoprotein Ibalpha to its cognate ligand A1(vWF). The findings provide evidence for a concerted action of the A1(vWF) and A3(vWF) domains in inducing platelet arrest on Col VI. This is accomplished via an interaction of the A1(vWF) domain with a site contained in the alpha3 chain A7(VI) domain and via a conformation-dependent interaction of the A3(vWF) domain with the intact tetrameric collagen. The data further emphasize that Col VI microfilaments linking the subendothelial basement membrane to the interstitial collagenous network may play a pivotal role in the hemostatic process triggered upon damage of the blood vessel wall. 相似文献
946.
Y Morikawa K Hoshino K Matsumura S Yoshioka J Yokoyama M Kitajima 《Canadian Metallurgical Quarterly》1998,33(11):1679-1681
BACKGROUND/PURPOSE: The mucosectomy of the aganglionic rectal mucosa has been performed transabdominally in the Soave procedure. Recently, mucosectomy with transanal approach was reported both in the laparoscopic and the open surgical procedure. However, the operative view and working field are restricted because the dissection has to be done in the anal canal. The authors report an innovative approach, an extra-anal mucosectomy, to perform mucosectomy in the Soave procedure for Hirschspung's disease in combination with the laparoscopic-assisted prolapsing technique. METHODS: Four patients underwent laparoscopic surgery for Hirschsprung's disease with extra-anal mucosectomy between 1995 and 1997. One 10-mm and 5-mm ports were used throughout the operation. The rectum was pulled out through the anal canal to create a rectal prolapse and was divided outside the anal canal. The mucosectomy was performed in the everted rectal mucosa outside the anal canal to the level of dentate line. The colon was sutured to the anal mucosa 2 mm above the dentate line. Mean operative time was 3 hours. RESULTS: The present technique made the whole mucosectomy possible under direct observation. CONCLUSION: The extra-anal mucosectomy in conjunction with a laparoscopic-assisted prolapsing technique seems to be a safe and reliable modality in the surgical treatment of Hirschsprung's disease. 相似文献
947.
948.
Feng-Chen Li Yasuo Kawaguchi Koichi Hishida 《International Journal of Heat and Mass Transfer》2005,48(5):965-973
Turbulence transport features in a heated drag-reducing surfactant solution (CTAC, 30 wppm) channel flow was investigated by simultaneously measuring velocity and temperature fluctuations in the thermal boundary layer. Measurement was made at inlet fluid temperature of 304 K and at three Reynolds numbers (based on channel height, bulk velocity and solvent viscosity): 3.5 × 104, 2.5 × 104 and 1.5 × 104. Structural analysis showed that the drag-reducing additives inhibited the motions associated with ejections of low-momentum fluid away from the wall and sweeps of high-momentum fluid toward the wall (the second and fourth quadrant motion respectively) but had no obvious effect on the outward motion of high-momentum fluid and wall-ward motion of low-momentum fluid (the first and third quadrant motion respectively). The depression of wall-normal turbulent heat flux was due to the decreased contributions of the second and fourth quadrant motions. 相似文献
949.
溶剂法制备聚合物分散液晶膜 总被引:5,自引:0,他引:5
用溶剂法制备了聚合物分散液晶膜。采用偏光显微镜、扫描电子显微镜和电光仪对相分离和聚合物分散液晶材料的电光性能作了初步探讨。研究结果表明,升温速度和聚合物含量对PDLC膜的相分离结构和响应电压有显著的影响。 相似文献
950.
Yasuo Chikata Noboru Yasuda Manabu Matsushima & Tameo Kobori 《Computer-Aided Civil and Infrastructure Engineering》1998,13(4):255-264
Scenery evaluation depends on the evaluator's experiences or perceptions. Thus inverse analysis by neural networks of scenery evaluation of planted concrete structures (concrete retaining walls) was examined in this study. In addition, in order to identify the evaluation schemes of evaluators, sensitivity analysis was performed on the obtained neural network structure. The efficacy of neural network inverse analysis and genetic algorithm analysis using fuzzy-set theory in reproduction of the same scenery evaluation questionnaire's results also was compared. 相似文献