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排序方式: 共有7501条查询结果,搜索用时 15 毫秒
991.
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Mikami Y. Nagae Y. Mori Y. Kuwabara K. Saito T. Hayama H. Asada H. Akimoto Y. Kobayashi M. Okazaki S. Asaka K. Matsui H. Nakamura K. Kaneko E. 《Electron Devices, IEEE Transactions on》1994,41(3):306-314
A new concept to produce large thin film transistor liquid crystal displays (TFT-LCD's) without using an optical mask aligner is proposed which emphasizes patterning technology. Some experimental thin film transistors (TFT's) are fabricated according to the concept and operated like conventional transistors fabricated by using an optical mask aligner. The concept includes improvement of printing technology and development of a double-layer resist method. The latter method employs a printed ink pattern and a photoresist. This prevents contamination of thin films by metal impurities which affect electrical characteristics of the TFT's. A special gravure offset printing technology is proposed, composed of a large thixotropy valued UV ink, and a fine, precision etched glass intaglio. The experimental TFT's, with a designed minimum gate length of 10 μm, have comparable electric characteristics to those of conventional poly-Si TFT's 相似文献
995.
The clinical features of 53 cases of intercalated hypoplasia and 113 cases of distal aplasia are reviewed and compared with each other and with 129 cases of syndactyly. Tri-, di- and mono-phalangeal symbrachydactyly, and adactyly with nubbin digits are consecutive anomalies. Transverse deficiency may result if the mesenchyme is damaged severely, and if damage is mild and formation has continued, intercalated transverse deficiency may occur. Webbing in symbrachydactyly may result from failure of the apical ectodermal ridge under the influence of damaged mesenchyme. 相似文献
996.
Akira Tonomura 《Journal of Superconductivity》1994,7(2):265-267
Individual vortices in superconductors are directly observed with our holography electron microscope. Vortices cannot be viewed as an electron micrograph, but only as a holographic interference micrograph or a defocused micrograph (Lorentz micrograph), since vortices are phase objects to the illumination electron beam. Since the flux itself, and not its replica, is detected, even the dynamic behavior can be observed. The dynamics of vortices in a Nb thin film can be observed in real time when the sample conditions, such as the temperature or the applied magnetic field, change. 相似文献
997.
Development of heart failure complicating acute myocardial infarction is directly related to the extent of myocardial infarction and complex architectural changes defined as infarct expansion and remodeling. ACE inhibitors are an exciting class of agents that have the potentiality to prevent left ventricular dilatation, evolution of heart failure and death in the acute myocardial infarction setting. Besides, reperfusion is a important intervention that prevents infarct expansion in the early period after myocardial infarction. Early reperfusion limits expansion by infarct size reduction while late reperfusion reduces expansion independent of myocardial salvage by limiting transmural damage and improving the infarct healing. Therefore, reperfusion therapy decreases the incidence of congestive heart failure and significantly improves the prognosis of heart failure. On the other hand, the in-hospital mortality rate of cardiogenic shock, resulting from acute myocardial infarction, remains high, although primary PTCA has apparently resulted in substantial improvement in mortality of myocardial infarction shock. Thus, reperfusion treatment may be more effective in preventing rather than treating cardiogenic shock. 相似文献
998.
999.
T Mizushima F Tajima T Nakamura M Yamamoto KH Lee H Ogata 《Canadian Metallurgical Quarterly》1998,29(3):607-612
BACKGROUND AND PURPOSE: Autonomic dysfunction is frequently present in patients with cerebrovascular accidents (CVA). However, the pathophysiological mechanisms of these disorders are not clear. The purpose of the study was to assess the effects of CVA on the autonomic nervous system. METHODS: In eight male patients with a history of CVA with damage of the cortical or subcortical structures, we measured the cold pressor response during recording of muscle sympathetic nerve activity (MSNA) from the peroneal nerve on the hemiplegic side. We also studied 10 age-matched male control subjects. Tests were performed before, during, and after immersion of the nonhemiplegic hand in ice water for a period of 3 minutes in each phase. We also recorded changes in heart rate (HR), arterial blood pressure, skin temperature of the middle finger, and perception of pain using the Borg's score. RESULTS: During the control period, the mean burst count of MSNA in CVA (57.2 +/- 3.9 beats/100 HR) was higher than in control subjects (36.3 +/- 3.2 beats/100 HR) (P<.05). Total MSNA (the mean burst amplitude per minute times burst rate) increased significantly in CVA and control during the immersion period by 79.9 +/- 18.4% and 133.1 +/- 25.6%, respectively. The percent change in total MSNA in CVA was attenuated during immersion compared with control subjects. The HR and skin temperature responses as well as the Borg's score were similar in both groups during control, hand immersion, and recovery periods. CONCLUSIONS: The present results suggest that increased MSNA in CVA may be due to damage of cortical or subcortical structures or stroke-related changes in other areas or nonspecific changes that cause continuous increase in basal MSNA. 相似文献
1000.
K Takahashi N Nakamura T Terada T Okano T Futami H Saito KI Inui 《Canadian Metallurgical Quarterly》1998,286(2):1037-1042
Two H+/peptide cotransporters, PEPT1 and PEPT2, are expressed in the kidney, mediating the renal tubular reabsorption of oligopeptides and beta-lactam antibiotics. We examined the interactions of beta-lactam antibiotics with peptide transporters in rat renal brush-border membranes by evaluating the inhibitory potencies of the antibiotics against glycylsarcosine transport. Western blot analysis revealed that PEPT1 and PEPT2 were expressed in the renal brush-border membranes with the apparent molecular masses of 75 and 105 kDa, respectively. Using renal brush-border membrane vesicles, the uphill transport of glycylsarcosine was observed in the presence of an inward H+ gradient and an inside-negative membrane potential. Two transport systems with high affinity (Km of 50 microM) and low affinity (Km of 1.2 mM) appeared kinetically to mediate the glycylsarcosine uptake. The inhibition constants of the antibiotics for glycylsarcosine transport were more closely correlated with those in stable LLC-PK1 cells transfected with rat PEPT2 rather than PEPT1 cDNA. The beta-lactam antibiotics with an alpha-amino group showed trans-stimulation effects on the glycylsarcosine uptake, suggesting that these antibiotics and glycylsarcosine share a common peptide transporter. However, the antibiotics lacking an alpha-amino group failed to show the trans-stimulation effect. It is concluded that amino-beta-lactam antibiotics at therapeutic concentrations interact predominantly with PEPT2 localized in the brush-border membranes of rat kidney. 相似文献