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排序方式: 共有490条查询结果,搜索用时 15 毫秒
61.
M Yamakoshi K Suzuki T Nakakita N Goto A Nakamura Y Yamada 《Canadian Metallurgical Quarterly》1998,72(9):876-882
The purpose of this study was to investigate what viruses infiltrate into our nursing home, assess the related clinical symptoms in elderly subjects, and compare the incidence of infections with those in the general community. Between July 1994 and June 1995, 40 elderly persons dwelling in the nursing home were evaluated by clinical observation, serologic analysis, and viral culture of samples to determine the presence of viruses. Enteroviruses and herpes simplex I virus could be isolated from asymptomatic elderly subjects. Individuals with influenza B virus and RSV infections diagnosed by serology did have clinical symptoms. The prevalence of both influenza B virus and enteroviruses was related to that of such viruses in the general community. Our data suggest that respiratory viruses are readily transmitted from the community to nursing home residents. 相似文献
62.
Makoto Murakami Ken-ichi Suzuki Hideki Maeda Tetsuo Takahashi Akira Naka Norio Ohkawa Mamoru Aiki 《Optical Fiber Technology》1997,3(4):320-338
Optical amplifier techniques have led to the installation of large-capacity submarine systems and further capacity increases seem likely. This paper reviews the FSA submarine system, which flexibly operates at both 2.5 and 10 Gb/s and offers maximum transmission capacity of 60 Gb/s for commercial use. The system configuration as well as its characteristics and upgradability will be introduced, including measurement results on time-division-multiplexing/wavelength-division-multiplexing (TDM–WDM) transmission at bit rates of 10 and 20 Gb/s using non-return-to-zero or soliton pulses. To further increase transmission capacity, TDM–WDM techniques that permit more than 10 Gb/s signal transmission in each data channel should be developed. Thus, pulse formats, which include non-return-to-zero, return-to-zero, or soliton pulses, and dispersion allocation in transmission fibers are significant issues. We introduce and discuss our recent results from high-speed (10 to 40 Gb/s) TDM–WDM signal transmission experiments with regard to the above aspects. 相似文献
63.
Patch clamp method was used to search for, and characterize ion channel activity which may participate in cation influx in human myeloid K562 cells. In cell-attached, outside-out and whole-cell experiments two types of voltage-insensitive Na-permeable channels were identified with different selectivities for monovalent cations, referred to as channels of high (HS) and low (LS) selectivity. The unitary conductance was similar for both channel types being 12 pS (145 mmol/l Na, 23 degrees C). The relative permeability PNa/PK estimated from the extrapolated reversal potential values were 10 and 3 for HS and LS channels, respectively. Both HS and LS channels were found to be impermeable to bivalent cations (Ca2+ or Ba2+). The activity of HS and LS channels displayed a tendency to increase with depolarization. Both channel types were not blocked by tetrodotoxin and were insensitive to amiloride in the concentration range of up to 100 mumol/l. At higher concentrations (0.1-2 mmol/l), amiloride reversibly inhibited HS channels only. The results obtained lead us to conclude that, under physiological conditions, both types of Na-permeable channels may provide sodium influx in leukemic cells. Our data imply the existence of a novel family of Na channels in blood cells. 相似文献
64.
65.
Seiji Isoda Masaki Tsuji Masayoshi Ohara Akiyoshi Kawaguchi Ken-ichi Katayama 《Polymer》1983,24(9):1155-1161
The crystal structure of β-form poly(p-xylylene) is analysed starting from a high-resolution image of a single crystal of this polymer. The high-resolution image corresponding to the projection of molecules onto the ab-plane along the chain axis shows clearly the mutual position of each molecule in a unit cell. The molecules are aligned wavily in the direction along the a-axis and the rough positions of their centres in a unit cell can be determined from the image. The refinement of the structure is carried out by the usual least-squares method using the intensities of electron and X-ray diffractions. The space group of the β-form is trigonal, P3, and the lattice dimensions are a=2.052 nm, c=0.655 nm and γ=120°. The unit cell contains 16 molecules and one of them is considered to occupy statistically one of three equivalent orientations so as to satisfy the P3 symmetry. 相似文献
66.
Two studies examined the effects of an apology on a victim's aggression and explored the psychological mechanisms underlying such effects. In Study 1, female undergraduates were psychologically harmed and then received an apology by another female student. In Study 2, male undergraduates were asked to role play a victim in a hypothetical harm situation. Results indicate that when the harm-doers apologized, as opposed to when they did not, the victim-subjects refrained from severe aggression against them. Regression analyses suggested that such aggression-inhibitory effects of an apology were mediated by impression improvement, emotional mitigation, and reduction in desire for an apology within the victims. It was also found that when the harm was severe, such effects of an apology on aggression were attenuated. The more severe the harm is, the more extensive of an apology may be needed to alleviate the victim's anger and aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Hakoshima Toshio; Toda Shoji; Sugio Shigetoshi; Tomita Ken-ichi; Nishikawa Satoshi; Morioka Hiroshi; Fuchimura Kayoko; Kimura Tsuyoshi; Uesugi Sei-ichi; Ohtsuka Eiko; Ikehara Morio 《Protein engineering, design & selection : PEDS》1988,2(1):55-61
Recognition by ribonuclease T1 of guanine bases via multidentatehydrogen bonding and stacking interactions appears to be mediatedmainly by a short peptide segment formed by one stretch of aheptapeptide, Tyr42-Asn43-Asn44-Tyr45-Gly46-Gly47-Phe48. Thesegment displays a unique folding of the polypeptide chainconsistingof a reverse turn, Asn44-Tyr45-Glu46-Gly47, stabilized by ahydrogen-bond network involving the side chain of Asn44, themain-chain atoms of Asn44, Gly47 and Phe48 and one water molecule.The segment is connected to the C terminus of a ß-strandand expands into a loop region between Asn43 and Ser54. Lowvalues for the crystallographic thermal parameters of the segmentindicate that the structure has a rigidity comparable to thatof a ß-pleated sheet. Replacement of Asn44 with alanineleads to a far lower enzymatic activity and demonstrates thatthe side chain of Asn44 plays a key role in polypeptide foldingin addition to a role in maintaining the segment structure.Substitution of Asn43 by alanine to remove a weak hydrogen bondto the guanine base destabilized the transition state of thecomplex by 6.3 kJ/mol at 37°C. In contrast, mutation ofGlu46 to alanine to remove a strong hydrogen bond to the guaninebase caused a destabilization of the complex by 14.0 kJ/mol.A double-mutant enzyme with substitutions of Asn43 by a histidineand Asn44 by an aspartic acid, to reproduce the natural substitutionsfound in ribonuclease Ms, showed an activity and base specificitysimilar to that of the wild-type ribonuclease Ms. The segmenttherefore appears to be well conserved in several fungal ribonucleases. 相似文献
68.
Wada O. Yamakoshi S. Abe M. Nishitani Y. Sakurai T. 《Quantum Electronics, IEEE Journal of》1981,17(2):174-178
The fabrication of high radiance InGaAsP/InP double-heterostructure (DH) surface-emitting LED's at 1.27 μm wavelength has been described. The elimination of the junction misplacement as well as the optimization of the active layer thickness has been found to be important in realizing high quantum efficiency. An ideal DH, free from the junction misplacement, has been fabricated by using Cd as the dopant in the InP carrier confining layer. The active layer thickness for maximum output power has been determined to be1-1.5 mu m. Furthermore, a new fabrication technique has been developed and the LED structure, which has a lens monolithically formed on the InP substrate, has been fabricated for the first time at this wavelength. This lensed LED improves the coupling efficiency greatly, 2.7 times that of the flat LED's. A maximum coupled power of approximately 0.20 and 0.31 mW has been attained at 100 mA for 85 μm core, 0.16 NA and 100 μm core, 0.25 NA step index fibers, respectively. 相似文献
69.
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
70.
Human placenta gangliosides 总被引:2,自引:0,他引:2
Takao Taki Ken-ichi Matsuo Kaname Yamamoto Toshiko Matsubara Akira Hayashi Tadayuki Abe Makoto Matsumoto 《Lipids》1988,23(3):192-198
Gangliosides extracted from human placenta were composed of four major components (G1–G4), which were purified by silica beads
column chromatography. The structures of these gangliosides were analyzed by exoglycosidase treatments, 400 MHz proton magnetic
resonance spectroscopy and gas chromatography-mass spectrometry and were concluded to be as follows:
Gangliosides containing more than 10 sugar residues were observed in addition to the above four major components. But ganglio-series
gngliosides were undetectable in the placenta. 相似文献