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991.
Mucous barrier was searched by the histochemical method of mucopolysaccharides and by the measurement of precipitated mucus of gastric juice. The neutral polysaccharide stored within the surface epithelial cells must be a source of the mucus of the gastric juice. The storage of the polysaccaride was decreased by a long-term stimulation by histamine, and the precipitated mucus volume was also decreased shortly after the stimulation. Therefore, some kind of the stimulation for the gastric secretion must be avoided for prevention of peptic ulcer. The oral administration of the sulfuric polysaccharide extracted from seaweed prevented the occurrence of experimental ulcer. It may be concluded that the exogeneous polysaccaride can take the place of the endogenous polysaccharide. 相似文献
992.
993.
994.
A novel InP/InGaAsP buried heterostructure laser diode on p-type InP substrate has been developed. The laser has achieved a threshold current as low as 20 mA DC with high power output of 50 mW under CW operation in the fundamental transverse mode. 相似文献
995.
996.
The effects of the onset of lasing on the I-V characteristics, the impedance characteristics and the light modulation characteristics of laser diodes have been discussed by introducing the rate equations which involve carrier diffusion process in the active layer interacting with the radiation field intensity. The static I-V characteristics exhibit a kink at lasing threshold current, reflecting the decrease of effective lifetime of carriers. Effective carrier lifetimes decrease with increasing light intensity, which results in a steep attenuation of injected carrier density in the active region. The impedance and light modulation characteristics are obtained in the small signal approximation. The small signal light modulation characteristics depend strongly on whether the laser diode is excited by the constant current modulation or the constant voltage modulation. The impedance is changed drastically by the onset of lasing and exhibits a resonance which coincides exactly with the optical modulation resonance frequency. 相似文献
997.
Kunihiro Hamaba Naoto Yokoyama Masakazu Kato Yoshiki Takabayashi 《Electrical Engineering in Japan》1992,112(2):101-109
A technique of calculating the frequency bias of an electric power system from frequency fluctuation data and total output power is described. An evaluation method for testing the calculations by the new method is developed. The results are in good agreement with estimates based on generator speed regulation but the method gives an excessively high figure for the load frequency bias. 相似文献
998.
Johnson Ronald C.; Suzuki Nancy S.; Olds William K. 《Canadian Metallurgical Quarterly》1964,69(2):233
An analysis of previous studies suggested that certain letters and letter combinations occur more often than would be expected by chance in affectively pleasant words, while others are overrepresented in unpleasant words. On the basis of data from these prior investigations, 14 pairs of artificial words were constructed and randomly paired with 7 good and 7 bad adjectives. College, deaf high school, and hearing high school Ss were presented with the task of matching each of the English adjectives with the correct member of the artificial word pair presented with it. The college and hearing high school Ss matched as predicted significantly more often than chance expectancy, which deaf Ss did not. The results are interpreted as supporting the existence of phonetic symbolism of word sounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
This paper summarizes our research on newly-developed multifilamentary V3Ga and Nb3Sn compound superconductors, including their design, processing, and characteristics such as mechanical and superconducting properties, and coil performance. 相似文献
1000.
Shimazu Hideaki Yamakoshi Ken-Ichi Togawa Tatsuo Fukuoka Masakazu Ito Hiroshi 《IEEE transactions on bio-medical engineering》1982,(1):1-7
We devised a compensation technique that measures the admittance change of a limb submerged in an electrolyte solution in a cylinder. Using this technique, we evaluated the accuracy of admittance plethysmography and the validity of the parallel-conductor model on which the theory of blood flow measurement by electrical admittance (or impedance) plethysmography is based. From a theoretical point of view, if a limb is regarded as a parallel-conductor model, the admittance change due to blood pooling following venous occlusion should disappear when the resistivity of the solution is equal to that of the blood. 相似文献