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排序方式: 共有1776条查询结果,搜索用时 31 毫秒
971.
Kazuyuki Wada Shigetaka Takagi Zdzislaw Czarnul Nobuo Fujii 《Analog Integrated Circuits and Signal Processing》1996,11(2):119-128
This paper proposes a topology-independent predistortion for filters using integrators. This employs integrators having the same structure, the same-value elements and an electrically controllable unity-gain frequency and compensates for the deviation of frequency characteristics due to excess phase shifts of integrators without knowledge of a filter topology. The effectiveness of the proposed method is demonstrated through SPICE simulations. 相似文献
972.
973.
Matsumoto Y. Takeuchi M. Fujii K. Sugiura A. Yamanaka Y. 《Electromagnetic Compatibility, IEEE Transactions on》2003,45(3):561-565
A time-domain noise model is developed for analyzing the performance degradation of wireless communication systems in the 2.4 GHz band caused by microwave ovens, taking into account the noise generation mechanism and its characteristics. The proposed noise model consists of a series of frequency-modulated tone bursts, which can be realized with a set of FM/AM modulators. It yields a simple and general expression of the noise waveform in terms of six parameters that can be determined from measurements. Band-limited noise waveforms can also be derived from the model via simple approximations. Comparisons of both the waveform and the frequency spectrum are made between actual noise and the proposed model, which clearly demonstrate the validity and usefulness of the model. 相似文献
974.
T Yoshimura H Yokoyama S Fujii F Takayama K Oikawa H Kamada 《Canadian Metallurgical Quarterly》1996,14(8):992-994
Nitric oxide (NO), a simple diatomic free radical, is known to play a critical physiological role in diverse organisms. An iron complex, with N-(dithiocarboxy)sarcosine (Fe-DTCS), has a high affinity for endogenous NO and can trap, stabilize, and accumulate it. The stable NO adduct thus formed is detectable at room temperature with electron paramagnetic resonance (EPR) spectrometry. We report in vivo EPR imaging of endogenous NO, trapped by an Fe-DTCS complex, in the abdomen of a live mouse. To our knowledge, this is the first report on EPR imaging of endogenous free radicals produced in vivo. This EPR imaging method will be useful for the noninvasive investigation of the spatial distribution of NO in pathologic organs or tissues. 相似文献
975.
T Fujimura H Fujii K Ariizumi T Minami S Odagiri S Koide 《Canadian Metallurgical Quarterly》1996,21(1):25-31
Over the years there have been sporadic reports of unusual cystic lesions of the jaws, not readily classified under conventional headings but which have been variously diagnosed as median-mandibular, glandular, sialo-odontogenic or botryoid odontogenic cyst. We present five cases which do not fit into other categories of odontogenic cyst, two of which have recurred within a few years of conservative treatment. This paper aims to alert clinicians to the propensity for regrowth of these cysts, proposes the term polymorphous odontogenic cyst for these lesions, to encompass their varied histological appearances and discusses their distinction from other cyst types with mucous and papillary formations in epithelium. 相似文献
976.
M Fujii Y Ohno Y Tokumaru Y Imanishi M Kanke 《Canadian Metallurgical Quarterly》1996,23(13):1740-1746
Combination chemotherapy with CDDP and 5-FU is one of the effective regimens for head and neck cancer. We studied the difference in the effects and adverse effects between two kinds of schedules of CDDP administration for CDDP-5-FU combination chemotherapy. For 13 patients, CDDP was administered on 5 consecutive days from day 1 to day 5 at a daily dose of 16 mg/m2 (Regimen A). For 14 patients CDDP was administered 80 mg on day 1 (Regimen B). 5-FU was administered 700 mg/m2/ day as a continuous drip infusion for 120 hours from day 1 to day 5. For regimen A, the response rate was 77%; for regimen B, it was 64%. The pattern of adverse effects showed a difference. Regimen B was more toxic for renal function than regimen A. But regimen A showed toxicity for bone marrow function. Acute phase nausea and vomit appeared more frequently in regimen B. The difference in the adverse effect pattern, which depends on the schedule of CDDP administration, seems important in order to apply this regimen for head and neck cancer patients safely. The schedule of CDDP administration should be changes depending on the renal and bone marrow function of patients. In order to evaluate the efficacy of UFT as adjuvant chemotherapy, UFT was administered p.o. to patients with maxillary sinus carcinoma for more than one year after definitive treatment with surgery or radiotherapy. Fifteen patients with UFT adjuvant chemotherapy showed significantly better survival rates than patients without adjuvant chemotherapy. We also studied adjuvant chemotherapy with CBDCA and FT for patients with advanced head and neck cancer. Administration with UFT (600 mg/day) from day 1 to day 14 with CBDCA 350 mg/m2 at day 7 was repeated more than twice. This regimen showed low toxicity and better survival for nasopharyngeal cancer patients. More clinical trials with this regimen for adjuvant chemotherapy are needed. 相似文献
977.
R Fujii Y Imahori M Kimura K Toyama M Yuasa Y Kumakura H Horii K Wakita T Yagyu T Nakamura T Ido S Ueda T Kanatsuna 《Canadian Metallurgical Quarterly》1997,34(11):1055-1061
6-[18F]Fluoro-L-dopa (L-3,4-dihydroxy-6-[18F]fluorophenylalanine; 6-[18F]FDPA) is useful to assess presynaptic dopamine metabolism in central nervous system. In this paper, we report on the usefulness of the 6-[18F]FDOPA synthesis system developed for the routine synthesis. This system consists of the 6-[18F]FOPA synthesis and the separation units in conjunction with controller using a personal computer. The synthesis time of 6-[18F]FDOPA was 73 minutes. The typical yield and specific activity were 1.4-2.4 GBq and 244-270 MBq/mumol at the end of synthesis, respectively, under the irradiation condition of 50 microA for 130 minutes. The radiochemical yields of 6-[18F]FDOPA were 31.3-38.7% based on the [18F]acetylhypofluorite, and the results were affected with the condition of potassium acetate (AcOK) to produce gaseous [18F]acetylhypofluorite. This system is useful for the routine production of 6-[18F]FDOPA because of its high yield and high specific activity while maintaining AcOK in good condition, and decreasing the radiation exposure for chemist. 相似文献
978.
M Fujii T Higuchi S Mukai M Yonekura T Yano H Kawaguchi K Nonaka T Fukunaga Y Sugimoto S Yamada 《Canadian Metallurgical Quarterly》1996,60(10):1575-1579
We have reported a inhibitor of acid lipases in liver lysosomes and erythrocytes from chickens [M. Fujii et al., Int. J. Biochem., 22, 895-898 (1990)]. In this paper, the properties of the inhibitor were described in comparison with those of apo A-I of chicken. The purified inhibitor migrated with the same mobility on SDS-PAGE as apo A-I, and had a molecular weight of 27,000. The peptide map from the lipase inhibitor was similar to that of apo A-I. Antibodies to the acid lipase inhibitor also reacted with apo A-I. Apo A-I inhibited the acid lipase activities of liver lysosomes and erythrocytes from chickens as strongly as the lipase inhibitor. The N-terminal amino acid sequence of lipase inhibitor was identical to that of apo A-I as far as residue 20. The amino acid sequence of peptides obtained from the inhibitor by cleavage with CNBr corresponded to internal sequence of apo A-I, and so the CNBr-peptides were derived by cleavage after the methionine residues in apo A-I. The findings showed that the inhibitor of the acid lipases in liver lysosomes and erythrocytes from chickens was identical to apo A-I. 相似文献
979.
Mohammed Ismail Robert Brannen Shigetaka Takagi Nobuo Fujii Nabil I. Khachab Ronny Khan Oddvar Aaserud 《Analog Integrated Circuits and Signal Processing》1994,5(3):219-234
The design of five simple CMOS opamp based multipler/divider circuits is presented. Each two opamp and six MOSFET transistor circuit simultaneously achieves four-quadrant multiplication and division. Applications of the new circuits in analog signal processing and neural networks are discussed. The multiplier/divider circuits are all insensitive to MOS intrinsic parasitic capacitances. They do, however, exhibit different sensitivities to opamp finite unity-gain bandwidth. These sensitivities may be mitigated using the configurability property of the circuits. Finally experimental results are provided to support some of the theoretical claims. 相似文献
980.