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71.
Isao Sakaguchi Varanasi Srikanth Takayasu Ikegami Hajime Haneda 《Journal of the American Ceramic Society》1995,78(9):2557-2559
The volume and grain boundary diffusion coefficients (Dv and δDgb ) of oxygen at 1673 K in pure and Mg-doped alumina were studied by using a resistive anode encoder of SIMS. The effect of Mg-doping on Dv , was observed clearly. The differences on δDgb in pure and Mg-doped alumina were about 3 orders and 1 order of magnitude, respectively. The Mg-doping in alumina is useful for homogenizing grain boundary diffusion. 相似文献
72.
Minami T. Yamaguchi K. Nakagami T. Takanashi H. Fujino N. Hamano H. Suyama M. Iguchi K. Yamada I. 《Selected Areas in Communications, IEEE Journal on》1985,3(6):849-858
This paper describes a 200 Mbit/s multiservice optical local area network (LAN) using a synchronous TDM loop structure. The LAN consists of a central supervisory node and multiple service nodes connected by an optical fiber loop. Each service node supports communication channels which have access to allocated time slots in TDM frames continuously circulating on the loop. Multiple independent communication paths of various speeds up to 140 Mbits/s and various modes including point-to-point, ring, and multicast, can be provided between the channels on the loop. The ring will be useful to support ring networks, such as a token ring. The structure of this LAN is quite suitable for integration of multiple services, including video, image, data, and voice, since each service can independently choose its own speed, access method, and mode. In this development, various LSI-based high-speed hardware technologies including compact E/O and O/E modules, GaAs 4 × 4 matrix switch LSI's, and high-speed TDM-processor LSI's, which are versatilely applicable to high-speed LAN's ranging from 100 Mbits/s up to 560 Mbits/s, have been successfully introduced and compact LAN equipment has been obtained. This paper deals mainly with the system and hardware structure of this LAN, together with high-speed hardware technologies. An outline of firmware and network operation, and an application example are also described. 相似文献
73.
T Narisawa Y Fukaura M Hasebe S Nomura S Oshima H Sakamoto T Inakuma Y Ishiguro J Takayasu H Nishino 《Canadian Metallurgical Quarterly》1998,89(10):1003-1008
A liquid chromatographic/tandem mass spectrometric (LC/MS/MS) assay was developed for the quantitative determination of olanzapine (LY170053, OLZ) in human plasma and serum. Bond Elut C2 solid-phase extraction cartridges (single cartridge or 96-well format), in conjunction with a positive pressure manifold, were used to extract OLZ and its internal standard, LY170222, from the biological matrix. Chromatographic resolution of OLZ from endogenous plasma interferences and its metabolites was accomplished with a MetaChem monochrom HPLC (4.6 x 150 mm, dp 5 microns). Detection was effected with a Perkin-Elmer SCIEX API III Plus mass spectrometer using positive ion atmospheric pressure chemical ionization and a multiple reaction monitoring protocol. The linear dynamic range was from 250 pg ml-1 to 50 ng ml-1 of human plasma/serum using a 0.5 ml aliquot. The inter-day precision (relative standard deviation) and accuracy (relative error) in plasma ranged from 6.26 to 7.66% and from -3.54 to 7.52%, respectively. The intra-day precision and accuracy in serum ranged from 3.46 to 8.76% and from -8.06 to 12.46%, respectively. This assay is sensitive and selective, and will be used to support both human clinical and toxicological analyses. Furthermore, using the 96-well solid-phase extraction format, sample preparation can be easily automated. 相似文献
74.
WA Gantert MG Patti M Arcerito C Feo L Stewart M DePinto S Bhoyrul S Rangel D Tyrrell Y Fujino SJ Mulvihill LW Way 《Canadian Metallurgical Quarterly》1998,186(4):428-32; discussion 432-3
75.
S Adachi N Yamasaki T Ogasawara Y Takayasu T Takemura K Koyama 《Canadian Metallurgical Quarterly》1997,27(6):442-444
1. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are important in the control of body fluid homeostasis, blood pressure (BP) regulation and vascular remodelling. The genes for these peptides may, therefore, be involved in the pathogenesis of genetic hypertension. We have previously described a quantitative trait locus (QTL) for BP in the ANP gene region on rat chromosome 5. We have now assessed the possibility that this QTL lies at the closely linked BNP locus. 2. Intra-arterial BP and heart weight were measured in 12-week-old (n = 207) and 24-week-old (n = 88) F2 rats derived from crosses between Wistar-Kyoto normotensive rats and spontaneously hypertensive rats. We designed polymerase chain reaction primers to amplify a microsatellite in the BNP gene from genomic DNA. Analysis of variance was used for cosegregation analysis. Linkage mapping and localization of QTL was performed using the Mapmaker computer package. 3. A significant correlation was found between genotype for the BNP gene and systolic BP (P < 0.001) in 12-week-old rats. The ANP gene, but not the BNP gene, was associated with systolic BP in 24 week rats. There was no segregation of heart weight with BNP genotype at 12 or 24 weeks of age. The BNP gene mapped approximately 20 cM from the ANP gene in our rat hybrids, away from the previously described QTL. There was evidence for a second BP locus near to but distinct from the BNP gene. 4. These results suggest that BP QTL are present in the natriuretic peptide gene region but that the ANP and BNP genes themselves have no major effect on BP in this cross. 相似文献
76.
TC Winter K Takayasu Y Muramatsu H Furukawa F Wakao H Koga M Sakamoto S Hirohashi PC Freeny 《Canadian Metallurgical Quarterly》1994,192(2):379-387
PURPOSE: To determine the computed tomographic (CT) and magnetic resonance (MR) imaging appearances of early advanced hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty-seven surgically resected cases of early advanced HCC were studied with CT, CT during arterial portography, CT arteriography, and MR imaging. RESULTS: The sensitivity of standard CT (unenhanced, early, and late CT combined) for the detection of early advanced HCC was 81%, while that of standard MR imaging (T1- and T2-weighted MR imaging combined) was 83%. A nodule-in-nodule appearance was identified in approximately one-third to one-half of cases. Signal behavior of early and advanced components of early advanced HCC followed the expected behaviors of isolated early HCC and isolated advanced HCC, respectively. Tumor size was accurately estimated with standard CT and standard MR imaging. CONCLUSION: More research must be performed to ascertain whether any relationship exists between the different types of HCC and the clinical outcome. 相似文献
77.
78.
Tyrosine kinases activated by G protein-coupled receptors can phosphorylate and thereby suppress the activity of the delayed rectifier potassium channel Kv1.2. Using a yeast two-hybrid screen, we identified the small GTP-binding protein RhoA as a necessary component in this process. Coimmunoprecipitation experiments confirmed that RhoA associates with Kv1.2. Electrophysiological analyses revealed that overexpression of RhoA markedly reduced the basal current generated by Kv1.2 expressed in Xenopus oocytes. Furthermore, in 293 cells expressing Kv1.2 and ml muscarinic acetylcholine receptors, inactivating RhoA using C3 exoenzyme blocked the ability of ml receptors to suppress Kv1.2 current. Therefore, these results demonstrate that RhoA regulates Kv1.2 activity and is a central component in the mechanism of receptor-mediated tyrosine kinase-dependent suppression of Kv1.2. 相似文献
79.
80.
O Fujino K Hashimoto H Enokido H Komatsuzaki T Fujita Y Takaishi T Hirayama 《Canadian Metallurgical Quarterly》1996,28(6):515-519
Dizziness in childhood is not an infrequent symptom, but epileptic vertigo is a rare condition in children. Here we report an 8-year-old Japanese boy with epileptic vertiginous seizures. At age 8 years, he visited Nippon Medical School Hospital because of a ten day history of dizziness. The dizziness occurred more than twenty times a day and he was hospitalized. On physical examination, the patient appeared normal and there were no abnormal neurological findings, including eye movement and cerebellar signs. Ophthalmoscopy, otoscopy, vestibular function test and hearing test were normal. Computerized tomography scanning and MR imaging of the head revealed no significant abnormality. The dizziness observed on admission comprised sudden brief attacks of rotatory sensation without amnesia regarding the event. Sometimes the attacks were accompanied by tremor like movement and numbness of the right hand, followed by postictal unsteadiness. Interictal EEG revealed spike-and-wave complexes in the central region dominantly in the light sleep stage. On ictal EEG, seizure discharges were observed to begin in the left central region and they increased in amplitude and subsequently propagated to the frontal and occipital regions. These findings were most suggestive of partial seizures. The patient was treated with carbamazepine and the seizures became well under control. 相似文献