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951.
M Hashimoto T Miyauchi O Watanabe N Tomura J Watarai 《Canadian Metallurgical Quarterly》1995,13(5):205-208
The obstruction of a bowel segment at two points results in closed-loop obstruction, and is apt to cause strangulation. Thus, the early recognition of closed-loop small bowel obstruction might reduce the mortality rate. However, plain films are limited in their ability to diagnose it. Using previously described criteria, we retrospectively reviewed the CT images of six surgically confirmed cases of closed loop obstruction. In all patients, CT showed the characteristic configuration of closed loops, specific findings detected at the site of obstruction, or both. On the basis of our experience, CT is a useful, non invasive method for the investigation of patients with suspected closed-loop obstruction. 相似文献
952.
953.
Shusaku Hiraki Norio Watanabe Yoshiaki Ishihara Yuan-Ming Su 《Computers & Industrial Engineering》1994,27(1-4):205-208
This paper aims to design a production planning and control system to realize high productivity and low inventory in the international cooperative global complementary production system for mutual country's development. 相似文献
954.
Takashima D. Watanabe S. Nakano H. Oowaki Y. Ohuchi K. 《Solid-State Circuits, IEEE Journal of》1994,29(4):539-542
An open/folded bit-line (BL) arrangement for scaled DRAM's is proposed. This BL arrangement offers small die size and good array noise immunity. In this arrangement, one BL of an open BL pair is placed in between a folded BL pair, and the sense amplifiers (SA's) for open BL's and those for folded BL's are placed alternately between the memory arrays. This arrangement features a small 6F2 memory cell, where F is the device feature size, and a relaxed SA pitch of 6F. The die size of a 64-Mb DRAM can be reduced to 81.6% compared with the one using the conventional folded BL arrangement. The BL-BL coupling noise is reduced to one-half of that of the conventional folded BL arrangement, thanks to the shield effect. Two new circuit techniques, 1) a multiplexer for connecting BL's to SA's, and 2) a binary-to-ternary code converter for the multiplexer have been developed to realize the new BL arrangement 相似文献
955.
S Watanabe 《Canadian Metallurgical Quarterly》1993,97(7):851-856
I developed a new system of measuring ocular position using the first and fourth Purkinje images. This method used two images which were reflected from the front surface of the cornea and the back surface of the lens. I got a cross line from the first Purkinje image by putting a cross lens filter in front of the infrared camera. When I superimposed the vertical line upon the fourth image, I could get the optic axis of the eye. In order to measure the ocular position, I measured the angle of the optic axis. The accuracy of this system was +/- 0.1 degrees and the maximum error was smaller than +/- 0.5 degrees. Measurements with this system were easily obtained from squint patients and correlated well with results from the prism cover test (R2: 0.941). This measurement system was more useful than the prism cover test because I was able to measure horizontal deviations more precisely. 相似文献
956.
957.
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
958.
Thermoplastic resin and fiber-reinforced thermo-plastics (FRTPs) were used without post-cure treatment as “molded material.”
For such materials, creep behavior and physical aging occur simultaneously. This study examined the creep behavior of polycarbonate
(PC) and glass-fiber-reinforced polycarbonate (GFRPC) injection moldings, including the effect of physical aging and fiber
content, and determined that the time–temperature superposition principle could be applied to the creep behavior for different
fiber contents. The effects of physical aging on creep behavior were evaluated quantitatively on pure resin and with various
fiber contents without heat treatment. We found that the effect of physical aging could be evaluated with the proposed factor,
“aging shift rate.” To discuss the linearity of viscoelasticity in FRTPs, this study used two shift factors: time and modulus
shift factors. The fiber content affected creep behavior by both retarding and restraining it through changing the elastic
modulus. This was shown by generating a grand master curve of creep compliance, which included the effects of time, temperature,
and fiber content. Using the grand master curve of creep compliance and shift factors, it was possible to estimate the creep
deformation of molded materials under varying conditions and fiber contents. The estimated creep deformation gave a very good
fit to the experimental creep deformation. 相似文献
959.
K Watanabe H Ogi S Nakamura Y Kayano T Matsunaga H Yoshimura I Yamamoto 《Canadian Metallurgical Quarterly》1998,62(14):1223-1229
Anandamide (N-Arachidonoylethanolamine) amidohydrolase catalyzing hydrolysis of anandamide was characterized in mice. The enzymatic activity was highest in the liver, followed by the brain and testis. Negligible activity was found in heart, lung and spleen. The activity in brain and liver was mainly localized in the microsomal fractions. Kinetic experiments demonstrated that Km (microM) and Vmax (nmol/min/mg protein) for the brain microsomes were 9.3 and 2.58, respectively, while those for the hepatic microsomes were 180 and 18.9, respectively. The activity in the microsomes from the liver and brain was markedly inhibited by Cu2+, Hg2+, Se4+, phenylmethylsulfonylfluoride and sodium dodecylsulfate. Brain but not hepatic microsomal enzyme activity was inhibited by delta9-tetrahydrocannabinol, cannabidiol and cannabinol. Kinetic parameters demonstrated that the inhibition by the cannabinoids was competitive in nature. Relatively high distribution of the enzyme activity in brain suggests an importance of the enzyme in the central nervous system to regulate the neuromodulatory fatty-acid amides. 相似文献
960.