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21.
A diversity antenna comprising a short whip antenna top loaded with a small cylinder and a new built-in antenna has been developed for very small portable telephones in the 800-MHz band. Wire-grid analyses and whip antenna experiments yielded good radiation characteristic results when the equivalent electrical length of the whip antenna equalled a half wavelength. The built-in antenna features extreme compactness, its size being one-third that of a conventional planar inverted-F antenna. The characteristics were investigated experimentally, and an antenna of 3.5 cc volume with a gain of -1 dBd and a bandwidth of 30 MHz was designed at 879 MHz. Finally, the diversity characteristics were subjected to field measurements and a diversity correlation of 0.26 was obtained 相似文献
22.
T Oyama T Osaki T Mitsudomi R Ogawa R Nakanishi K Sugio K Yasumoto 《Canadian Metallurgical Quarterly》1998,1(5):823-826
We examined p53 protein expression, p53 gene mutation, proliferating cell nuclear antigen (PCNA), and argyrophilic nuclear organizer regions (AgNOR), in 30 patients with surgically-treated thymic tumors (26 thymoma and 4 thymic carcinoma cases). p53 expression ratio with DO-1 was divided as p53 negative (0% positivity), low expressor (<10% positivity), high expressor (>10% positivity). The incidence of p53 low and high expressor in thymoma were 19% (5/26) and 8% (2/26), respectively. p53 immunopositivity in thymoma was significantly correlated with PCNA labeling index (LI). p53 expression ratio in invasive thymoma (33%) tended to be higher than that in non-invasive thymoma (18%). p53 expression was detected in one of the thymic carcinoma. There were no p53 gene mutations in 15 invasive thymoma, although one of four (25%) thymic carcinomas showed two point mutations. p53 gene alterations seem to be associated with malignant activity of tumor cells, and therefore detection of p53 gene mutations is useful as a diagnostic factor. 相似文献
23.
Kazufumi Ogawa 《Polymer International》1992,28(1):25-33
Studies have been carried out on KrF excimer laser light (EX), X-ray or electron beam (EB) induced polymerization of 10,12-pentacosadiynoic acid (PDA) Langmuir-Blodgett (LB) films in relation to molecular density or molecular arrangement of the films using X-ray diffraction analysis, infrared (IR) spectroscopy and Raman spectroscopy. The molecular arrangement or density of the PDA LB films was controlled by subphase conditions when the films were built up, such as pH, temperature of a subphase or salt concentration in the subphase. Polymerization sensitivity of the PDA LB film was affected by the arrangement or molecular density. On low density (A type) films the polymerization occurred by irradiation with EX, X-ray or EB, but on high density (B type) films the polymerization occurred only when the irradiation was carried out by high energy beams such as X-ray or EB. Decomposition of polymerized films was observed further by excessive irradiation of EX or X-ray, but not on the B type films. It was revealed by X-ray diffraction analysis that in the A type film, the PDA molecules bent to a larger extent than those in the B type film and the polymerization proceeded topochemically, that is, the thickness decreased little after EB irradiation in a helium atmosphere. On the other hand, in the B type film, the thickness decreased by about 10% as a result of EB irradiation. By IR reflection-absorption (RA) and Raman measurements, it was confirmed that conjugated diacetylenic bonds disappeared and conjugated double and new conjugated triple bonds appeared after high energy beam irradiations. These results support the supposition that 1,4-polymerization, i.e. polydiacetylene type polymerization, occurs easily in the A type film and 1,2- or 3,4-polymerization, i.e. polyacetylene type polymerization, occurs in the B type film, and that the polymerized A type film was decomposed at the polydiacetylenic bond when the irradiation continued further. It was also shown that the polyacetylene type polymer was obtained only when the B type film was irradiated with the high energy beam. 相似文献
24.
S Yamada Y Takai K Nemoto Y Ogawa Y Kakuto A Hoshi K Sakamoto 《Canadian Metallurgical Quarterly》1992,31(5):563-567
Prognostic factors in esophageal carcinoma treated with irradiation were examined. The prognosis of 111 patients without metastasis who had received more than 60 Gy was analyzed. Significant associations were found between survival rates and tumor length, stage, radioresponse of the primary tumor and the s.c. X-P classification based on barium contrast radiography; superficial type (tumor limited to the surface of the esophageal wall), tumorous type (solid mass without ulceration), Ul-A type (tumor with shallow ulceration with regular margin), Ul-B type (tumor with deep ulceration or irregular ulcer margin), and funneled type (tumor invading the esophageal wall in a scirrhous pattern). In multiple regression analysis, the X-P classification had the strongest correlation with survival and the survival rates of patients with the superficial type, the tumorous type and the s.c. Ul-A type were significantly higher than those of patients with the other tumor types (p < 0.001). 相似文献
25.
The total volume change included gel and surrounded water with the swelling of five types of speherical cross-linked dextran (Sephadex) that are either nonionic (G) or possess one of four different ionic groups in the same molecular skeleton: CM: sodium carboxymethyl, SP: sodium sulphopropyl, DEAE: diethylaminoethyl chloride, and QAE: diethyl-(2-hydroxypropyl) aminoethyl chloride. All have been studied by dilatometry. The total volume decreased with the swelling of all Sephadexes. The maximum changes of total volume with the swelling in water were all negatives of CM, G, SP, (DEAE, QAE), which decrease in that order. These values did not depend on the concentration of sodium chloride and were closely related to the maximum heats of swelling. Total volume changes occurred by the dissociation of the ionic group of dextran derivatives that subtracted the total volume change due to hydration of Sephadex skeleton from the total volume change: ?21.6 ± 3.1 μL mmol?1 for CM, ?2.8 ± 8.0 μL mmol?1 for SP, +13.2 ± 4.4 μL mmol?1 for DEAE, and +15.4 ± 4.6 μL mmol?1 for QAE. These values are assumed to be reflected in the quantities of ions-water interaction of Sephadexes. © 1994 John Wiley & Sons, Inc. 相似文献
26.
27.
S. Arahira Y. Ogawa 《Photonics Technology Letters, IEEE》1996,8(2):191-193
Synchronous mode-locking was achieved in passively mode-locked semiconductor lasers using optical pulses with repetition rates at subharmonics of the cavity round-trip frequency. Stable and continuous mode-locked pulses at 8.5 GHz were generated when the repetition rate of the control optical pulses was 4.25 GHz (2nd subharmonic). The timing jitter of the mode-locked pulses was reduced to 1 ps. The relationship between repetition rates of the control pulses and the realization of stable and continuous mode-locking was examined. 相似文献
28.
S Takatsuki H Mitamura K Sueyoshi H Kanki I Furuno S Ogawa 《Canadian Metallurgical Quarterly》1998,39(5):687-697
One hundred and ninety-eight adolescents and their mothers (N = 189) and fathers (N = 136) participated in a 4-year longitudinal study. Adolescent problem behaviour was assessed by the Youth Self-Report (YSR) and the Child Behavior Checklist (CBCL). In addition, parental stress and marital adjustment were determined. Results showed that mothers and fathers showed high agreement, especially about their daughters, whereas parents and adolescents showed little agreement. Agreement was higher for internalising than for externalising behaviours. In general, adolescents reported more symptomatology than their parents did. However, mothers' ratings of their children's behaviours were significantly correlated with adolescents' self-ratings, but fathers' ratings were not. Statistical tests of correlations showed that mothers experiencing stress caused by marital problems perceived more problem behaviours in their children. Fathers' perceptions were relatively unaffected by personal adjustment. However, poor marital adjustment perceived by both parents showed a significant negative relation to adolescent externalising problem behaviour. 相似文献
29.
M Ogawa T Yamaguchi A Setiyono T Ho H Matsuda S Furusawa H Fukushi K Hirai 《Canadian Metallurgical Quarterly》1998,143(12):2327-2341
A flow cytometric virus binding assay that directly visualizes the binding of infectious bursal disease virus (IBDV) to its target cells was established. The chicken B lymphoblastoid cell line, LSCC-BK3, which is permissive for IBDV infection, bound high levels of the virus. Another B lymphoblastoid cell line, LSCC-1104-B1, bound low levels of the virus, although it was nonpermissive. No virus binding was detected in nonpermissive T lymphoblastoid cell lines. In the binding assay to heterogeneous cell populations of chicken lymphocytes, IBDV (a highly virulent OKYM strain) bound to 94% cells in the lymphocytes prepared from the bursa of Fabricius, 37% cells in those prepared from the spleen, 3% cells in those prepared from the thymus, and 21% cells in those prepared from the blood. Most of the cells, which bound the virus, were surface immunoglobulin M (SIgM)-positive, but a small number of them were SIgM-negative. Additionally, the binding of IBDV to the LSCC-BK3 cells was affected by treatment of the cells with proteases and N-glycosylation inhibitors. These findings may indicate that the IBDV host range is mainly controlled by the presence of a virus receptor composed of N-glycosylated protein associated with the subtle differentiation stage of B-lymphocytes represented mostly by SIgM-bearing cells. 相似文献
30.
M Hayashida K Ogawa Y Kawashima R Isoda M Sato C Fujimura T Yoneyama S Sawamura 《Canadian Metallurgical Quarterly》1998,47(8):933-938
The bed bath procedure consists of cleansing patients' body, passive position change, changing gown and making a bed. During the procedure, mixed venous desaturation was observed consistently in postoperative cardiac patients. We investigated the cause of the phenomenon in 22 patients undergoing cardiac surgery in their first postoperative day. The patients were breathing oxygen-enriched air via a Venturi mask. Cardiac index (CI), transluminal SvO2, arterial blood gas, Hb, DO2, VO2, FIO2, A-aDO2 and Qp/Qs were measured before and during the bed bath, while the patients were in the supine and left lateral position, respectively. Mean 8.5 +/- 1.5 minutes were required to complete the bed bath. During the bed bath, SvO2 decreased from 71 +/- 7% to 59 +/- 9% (P < 0.001), and returned to the baseline 6.5 +/- 7.4 minutes after the completion of the bed bath. VO2 increased markedly from 128 +/- 27 to 194 +/- 47 ml.min-1.m-2 (P < 0.001), while DO2 increased slightly from 480 +/- 91 to 513 +/- 110 ml.min-1.m-2 (P < 0.05). Among the determinants of DO2, CI increased slightly from 3.3 +/- 0.6 to 3.6 +/- 0.8 l.min-1.m-2, Hb remained unchanged and SaO2 decreased from 98.5 +/- 0.8 to 98.0 +/- 1.1%. FIO2 also decreased, while A-aDO2 and Qp/Qs remained unchanged. There was a negative correlation between VO2 change and SvO2 change, but no correlation between DO2 change and SvO2 change. There was a positive correlation between SaO2 change and SvO2 change, as well as between FIO2 change and SaO2 change. Therefore, the major cause of mixed venous desaturation was not the decreased DO2 or cardiopulmonary decompensation but the increased VO2 due to increased activity of the skeletal muscles. However, the decrease in SaO2 due to markedly increased O2 demand and the limited increase in CI might partially contribute to the marked decline in SvO2 through the limited increase in DO2. 相似文献