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11.
A Novel UWB Pulse Shape Modulation System 总被引:5,自引:1,他引:4
Ghavami Mohammad Michael Lachlan B. Haruyama Shinichiro Kohno Ryuji 《Wireless Personal Communications》2002,23(1):105-120
In this paper novel modified Hermite polynomial functions for use in impulse radio (ultra-wideband) communications are proposed. With these functions pulse shapes which are orthogonal and have nearly constant pulse width regardless of the pulse order are generated. These properties hold under the effects of differentiation. An M-ary communication system is constructed using these pulse shapes. A Matlab model for generating the pulses is designed and the effect of timing jitter on the performance of the system is investigated by computer simulation. 相似文献
12.
K Matsunaga M Oofukuji S Syukuwa M Osabe Y Takeno H Isomoto Y Mizuta S Kohno 《Canadian Metallurgical Quarterly》1997,24(15):2281-2284
The patient was a 83-year-old female with 2' T2-type gastric cancer associated with positive H. pylori in the lesser curvature of the stomach. The patient was treated with oral UFT-E alone in a daily dose of 400 mg. The tumor exhibited an O' IIa + IIc-like appearance 4 weeks after the start of administration and became scarred 8 weeks later, revealing marked tumor reduction in a short period of time. At 8 weeks, biopsy showed marked polymorphonuclear cells infiltration of gastric mucosa with no evidence of malignancy. In an attempt to eradicate H. pylori, 30 mg of lansoprazole, 400 mg of clarithromycin, and 2.0 g of ecabet-Na (3.0 g of Gastrom) were administered for 2 weeks. H. pylori was found to have been successfully eradicated, and the inflammatory lesions were no longer visible histologically. UFT-E was highly effective in this patient, and the eradication of H. pylori may contribute to the prevention of cancer recurrence. 相似文献
13.
OBJECTIVES: The three purposes of this study are to: (1) describe the relationship between the prevalence of coronal caries and root caries; (2) describe the relationship between the three-year incidence of coronal caries and root caries; and (3) if the two conditions are associated, develop a multiple regression model that identifies characteristics distinguishing people who had increments of both root caries and coronal caries from people who had increments of either coronal caries or root caries, or who had no new caries. METHODS: Dental examinations and interviews were conducted in the homes of a randomly selected, stratified sample of people over the age of 65 years in five North Carolina counties. The relationships between coronal and root D and DF were analyzed through contingency table analyses, and ordinal logistic regression was used to identify characteristics that differentiated people who had both coronal and root D over the three years from people who had either coronal or root D and people who had no new disease. RESULTS: Evidence of root and coronal caries in whites was much more likely to be in the form of fillings, while for blacks, it was more likely to be in the form of untreated decay. Prevalence rates of coronal and root D and DF were significantly associated for both blacks and whites. Incidence rates based on DF indicated that root and coronal caries were not associated in whites, but were associated in blacks. People more likely to experience both types of caries had more gingival recession at baseline, greater average attachment loss over the three years, and lactobacilli at baseline. In addition, the presence of Porphymonas gingivalis at three years was important for whites. CONCLUSIONS: It appears that coronal and root caries do tend to appear together in the same individuals, but fillings attenuate that relationship. The impact of dental treatment on the epidemiology of dental caries appears to be considerable and calls into question whether the F component of the caries index is related to disease as defined by epidemiologic criteria. 相似文献
14.
Hida H. Tsukada Y. Ogawa Y. Toyoshima H. Fujii M. Shibahara K. Kohno M. Nozaki T. 《Electron Devices, IEEE Transactions on》1989,36(10):2223-2230
The authors describe a novel design concept for enhancement (E) and depletion (D) mode FET formation using i-AlGaAs/n-GaAs doped-channel hetero-MISFET (DMT) and a novel self-aligned gate process technology for submicrometer-gate DMT-LSIs based on E/D logic gates. 0.5-μm gate E-DMTs (D-DMTs) with a lightly doped drain (LDD) structure show an average V t of 0.18 (-0.46) V, a V t standard deviation of 22.6 (24.9) mV, and a maximum transconductance of 450 (300) mS/mm. The V t shift is less than 50 mV with a decrease in gate length down to 0.5 μm. The gate forward turn-on voltage V f is more than 0.9 V, i.e. about 1.6 times that for MESFETs. This superiority in V f, preserved in the high-temperature range, leads to an improvement in noise margin tolerance by a factor of three. In addition, 31-stage ring oscillators operate with a power consumption of 20 (1.0) mW/gate and a propagation delay of 4.8 (14.5) ps/gate. Circuit simulation based on the experimental data predicts 140 ps/gate and 1 mW/gate for DMT direct-coupled FET logic circuits under standard loading conditions. DMTs and the technology developed here are very attractive for realizing low-power and/or high speed LSIs 相似文献
15.
16.
N Ide K Hirao Y Hata M Takeuchi M Irie I Yao M Deguchi A Toyoda H Nishioka A Mizoguchi Y Takai 《Canadian Metallurgical Quarterly》1998,243(2):634-638
In Caenorhabditis elegans, the vulval induction is mediated by tyrosine kinase receptor/Ras signal transduction pathway composed of the lin-3, let-23, and let-60 products. In addition to these gene products, the lin-2, lin-7, and lin-10 products are also implicated in this pathway. Lin-2 encodes a MAGUK and lin-7 encodes a small protein with one PDZ domain. The lin-10 product has no homology to known proteins. Here, we have cloned a rat homologue of the lin-10 product and characterized it. Rat lin-10 is ubiquitously expressed in various rat tissues and distributed in both the cytosol and membrane fractions. In brain, however, rat lin-10 is distributed only in the membrane fraction and enriched in the synaptic plasma membrane and postsynaptic density fractions. These results suggest that rat lin-10 is involved at least in synaptic functions in brain. 相似文献
17.
K Kohno JA Palha K Miyakawa MJ Saraiva S Ito T Mabuchi WS Blaner H Iijima S Tsukahara V Episkopou ME Gottesman K Shimada K Takahashi K Yamamura S Maeda 《Canadian Metallurgical Quarterly》1997,150(4):1497-1508
Amyloid fibrils derived from the Japanese, Portuguese, and Swedish types of familial amyloidotic polyneuropathy all consist of a variant transthyretin (TTR) with a substitution of methionine for valine at position 30 (TTR Met 30). In an attempt to establish an animal model of TTR Met-30-associated homozygous familial amyloidotic polyneuropathy and to study the structural and functional properties of human TTR Met 30, we generated a mouse line carrying a null mutation at the endogenous ttr locus (ttr-/-) and the human mutant ttr gene (6.0-hMet 30) as a transgene. In these mice, human TTR Met-30-derived amyloid deposits were first observed in the esophagus and stomach when the mice were 11 months of age. With advancing age, amyloid deposits extended to various other tissues. Because no significant difference was detected in the onset, progression, and tissue distribution of amyloid deposition between the ttr-/- and ttr+/+ transgenic mice expressing 6.0-hMet 30, endogenous normal mouse TTR probably does not affect the deposition of human TTR Met-30-derived amyloid in mice. TTR is a tetramer composed of four identical subunits that binds thyroxine (T4) and plasma retinol-binding protein. The introduction of 6.0-hMet 30 into the ttr-/- mice significantly increased their depressed serum levels of T4 and retinol-binding protein, suggesting that human TTR Met 30 binds T4 and retinol-binding protein in vivo. The T4-binding ability of human TTR Met 30 was confirmed by the analysis of T4-binding proteins in the sera of ttr-/- transgenic mice expressing 6.0-hMet 30. The T4-binding studies also demonstrated the presence of hybrid tetramers between mouse and human TTR subunits in the ttr+/+ transgenic mice expressing 6.0-hMet 30. 相似文献
18.
K Fukuoka M Hirokawa M Shimizu K Fujiwara I Kohno M Shintaku T Manabe 《Canadian Metallurgical Quarterly》1998,48(9):754-756
A case of oxyphilic cell variant of endometrioid adenocarcinoma is presented. To the best of our knowledge, there have been only three such cases reported in the English literature. The patient was a 35-year-old Japanese female (gravida 0, para 0). She was slightly obese with profuse vaginal bleeding. Histological examination of the resected uterus revealed endometrioid adenocarcinoma with an exclusive oxyphilic cell component. There was no evidence of myometrial invasion nor lymph node metastases. Reported cases of oxyphilic cell variant of endometrioid adenocarcinoma, including the present case, were stages 0-1 and grades 1-2. Although further study is necessary to evaluate this variant, oxyphilic cell variant seems to be an early stage of adenocarcinoma and should be differentiated from eosinophilic metaplasia and other types of adenocarcinoma of the endometrium. 相似文献
19.
Suemasu T. Kohno Y. Saitoh W. Watanabe M. Asada M. 《Electron Devices, IEEE Transactions on》1995,42(12):2203-2210
We report on the theoretical and measured characteristics of triple-barrier metal (CoSi2)-insulator(CaF2) (M-I) resonant tunneling transistors (RTT) grown on an n-Si(111) substrate, and the influence of their parasitic elements on the measured characteristics. First, we analyze theoretical characteristics of an M-I RTT, and then show fabrication process and current-voltage (I-V) characteristics obtained at 77 K, in which several degradations are observed: large resonance voltage, low peak-to-valley (P-V) ratios at negative differential resistance (NDR), and reverse base current. Analysis, taking several parasitic elements (e.g., base resistance, substrate resistance and leakage currents connected to the intrinsic transistor) into account, explains observed characteristics well. Finally, we show the first transistor action with large P-V ratios at 300 K, which is achieved by reducing collector-emitter leakage currents 相似文献
20.
Y Hirao S Ozono Y Kagebayashi M Yoshi Y Tani H Uemura H Momose E Okajima 《Canadian Metallurgical Quarterly》1996,42(10):795-804
The number of cases of prostate carcinoma (PCA) is steadily inceasing in Japan. The clinical application of a reliable tumor marker, prostate specific antigen (PSA) for the diagnosis, as well as the increasing elderly population in Japan may account for this increase. The subjects were patients at the Nara Medical University and its affiliated hospitals; 1) 687 cases without PCA were evaluated for age-specific PSA and the incidence of abnormal PSA following urological manipulations, 2) 135 cases with histological proven BPH by transurethral resection of prostate (TUR-P) were examined for PSA density (PSAD) and positive PSA rate in BPH, 3) 135 cases receiving a needle biopsy with suspicion of PCA were examined for the efficacy of PSA and PSAD and other parameters, and 4) 459 PCA cases treated between 1988 and 1994, were examined for specific PSA and PSAD values by stage and degree of cell differentiation. The PSA assay used in this study was MARKIT-M PA (normal range < or = 3.6 ng/ml). The PSA was decreased gradually with age in non-PCA patients, and abnormal PSA was found in 5.5% of these patients following manipulations. The average PSA was 2.95 +/- 2.03 ng/ml in 130 BPH patients (mean age: 71.1 +/- 7.0 years old. and average prostate volume: 32.9 +/- 16.1 ml). And abnormal PSA level (more than 3.61 ng/ml) was found in 22.3%. The mean PSAD was 0.1.0 +/- 0.06, and PSAD was below 0.15 in 86.1% of these BPH cases. Among the 135 cases receiving a needle biopsy, 33 cases had PSA values between 3.61 and 10.0 ng/ml. Of these cases, PCA was found in 18.5% of the 27 cases with a PSAD below 1.5, and in 33.3% of the 6 cases with a PSAD over 1.5. PSA and PSAD were proportionally increased with stage, and a significant difference in the PSA value was observed between stage B1 and B2, and stage C and D (P < 0.05). However, PSA and PSAD values were not significantly correlated with the cell differentiation in PCA stage A2-C. In total, PSA was 18.1 ng/ml in well, 23.9 ng/ml in moderately and 35.9 ng/ml in poorly differentiated type PCA. The positive rate of PSA was 22.3, 65.4 and 83.5%, that of prostate acid phosphatase (PAP) was 10.0, 17.8 and 45.8%, and that of GSM was 25.0, 14.7 and 68.4%, in BPH, stage A PCA and stage BPCA, respectively. In conclusion, PSA is the most reliable tool in the diagnosis of localized PCA. However, the differential diagnosis of BPH and localized PCA is difficult when the PSA value is between 3.61 and 10.0 ng/ml, and accurate staging of localized PCA is difficult with PSA or PSAD alone. At present, it is necessary to use all possible tools for the early detection of localized PCA, and to perform the needle biopsy in all PCA-suspicious cases. 相似文献