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排序方式: 共有455条查询结果,搜索用时 15 毫秒
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Azithromycin (AZM), a new macrolide antibiotic, in fine granules and in capsules was administered at a standard dose of 10 mg/kg once daily for 3 days to pediatric patients with bacterial infections. AZM was studied for its pharmacokinetic and clinical evaluation. 1. AZM possessed potent activity against Gram-positive bacteria and Gram-negative bacteria that had been clinically isolated. 2. Plasma samples were collected from two patients diagnosed as having pneumonia or enteritis, and urine samples were collected from one patient diagnosed as having pneumonia for drug level determination. The drug concentrations in plasma were 0.095 and 0.204 microgram/ml just before the end of treatment, and 0.017 and 0.096 microgram/ml at 48 hours post-treatment. The drug concentrations in urine were 5.16 micrograms/ml and 5.63 micrograms/ml during a period between 24 and 48 hours and between 48 and 72 hours after the start of treatment, respectively. 3. The drug was found effective in 37 of 38 cases with various pediatric infections. AZM treatment eradicated bacteria in 17 of 30 strains (56.7%). 4. One patient complained of mild vomiting, while abnormal laboratory test results indicating mild eosinophilia were reported in four cases. 相似文献
3.
C Nishiyama M Fukada Y Usui N Iwamoto T Yuuki Y Okumura H Okudaira 《Canadian Metallurgical Quarterly》1995,32(14-15):1021-1029
Der f 2 is a major mite allergen composed of 129 amino acid residues. To determine the major epitopes on Der f 2 recognized by human IgE antibodies, artificial mutations were introduced to Der f 2 protein. The IgE-binding activity of Der f 2 was significantly decreased by deletion of 10 amino acids at the N-terminus or nine amino acids at the C-terminus. Site-directed mutagenesis with a single amino acid replacement by Ala or Leu in both N- and C-terminal regions as well as a central portion was performed to generate 42 single-site mutations. Amino acid replacement around a disulfide bond of Cys8-Cys119 caused a marked decrease in IgE-binding activity. Furthermore, a distinct decrease in IgE-binding was also caused by Ala-substitution close to a disulfide bond of Cys73-Cys78 and by mutations of a few charged residues. From these results, it was concluded that the two disulfide-forming regions of Der f 2 and several charged residues are important for forming major epitope structures recognized by human IgE antibodies. 相似文献
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Masahiro Baba Goh Itoh Haruhiko Okumura 《Journal of the Society for Information Display》2007,15(3):205-211
Abstract— In this paper, a software‐processed edge‐ and level‐adaptive overdrive (SELAO) method, which is a novel overdrive technique that utilizes not only a temporal change of gray levels but also a spatial edge intensity of motion pictures, is proposed. The SELAO method is a software video‐processing technology to improve motion‐picture quality rendered on LCDs more than is possible with a conventional SLAO method without edge‐adaptive overdrive, and it works in real time on commonly used personal computers (PCs). 相似文献
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Yuko Habuta Naoaki Narishige Kazu Okumura Naonobu Katada Miki Niwa 《Catalysis Today》2003,78(1-4):131-138
Vanadium oxide spread highly on TiO2 (anatase, A) and SnO2, and rather densely on TiO2 (rutile, R) and ZrO2 to make the monolayer in less than 4–5 V nm−2. Profile of acid site of the monolayer was measured by temperature programmed desorption of ammonia, and its relation with the surface oxidation state was studied. The acid site density was high on the V2O5/TiO2 (A) independent of the degree of oxidation. On the other hand, that of V2O5/TiO2 (R) and V2O5/ZrO2 depended on the oxidation state, and the high value of the concentration was observed on the oxidized one. The strength of acid site generated on the V2O5 monolayer on TiO2 was as high as on the HZSM-5 zeolite. Turnover frequency (TOF) of propane conversion, and product selectivity were measured in propane oxidation. Among tested oxides, the V2O5/TiO2 (A) showed the high TOF and selectivity to form propylene, while those loaded on TiO2 (R) and ZrO2 the small TOF and poor selectivity. Therefore, the reaction profile of activity and selectivity could be related with the extent of spreading and solid acidity. An idea of limit of the acid site density ca. 1.5 nm−2 on the monolayer was elucidated. 相似文献
8.
Yoshiyuki Sakamoto Tomoyoshi Motohiro Shinichi Matsunaga Kohei Okumura Tomoyuki Kayama Kiyoshi Yamazaki Toshiyuki Tanaka Yoshimi Kizaki Naoki Takahashi Hirofumi Shinjoh 《Catalysis Today》2007,121(3-4):217-225
The release and reduction of NOx in a NOx storage-reduction (NSR) catalyst were studied with a transient reaction analysis in the millisecond range, which was made possible by the combination of pulsed injection of gases and time resolved time-of-flight mass spectrometry. After an O2 pulse and a subsequent NO pulse were injected into a pellet of the Pt/Ba/Al2O3 catalyst, the time profiles of several gas products, NO, N2, NH3 and H2O, were obtained as a result of the release and reduction of NOx caused by H2 injection. Comparing the time profiles in another analysis, which were obtained using a model catalyst consisting of a flat 5 nmPt/Ba(NO3)2/cordierite plate, the release and reduction of NOx on Pt/Ba/Al2O3 catalyst that stored NOx took the following two steps; in the first step NO molecules were released from Ba and in the second step the released NO was reduced into N2 by H2 pulse injection. When this H2 pulse was injected in a large amount, NO was reduced to NH3 instead of N2.
A only small amount of H2O was detected because of the strong affinity for alumina support. We can analyze the NOx regeneration process to separate two steps of the NOx release and reduction by a detailed analysis of the time profiles using a two-step reaction model. From the result of the analysis, it is found that the rate constant for NOx release increased as temperature increase. 相似文献
9.
Hidetsugu Nanba Natsumi Anzen Manabu Okumura 《International Journal on Digital Libraries》2008,9(2):151-161
The need for academic researchers to retrieve patents and research papers is increasing, because applying for patents is now
considered an important research activity. However, retrieving patents using keywords is a laborious task for researchers,
because the terms used in patents for the purpose of enlarging the scope of the claims are generally more abstract than those
used in research papers. Therefore, we have constructed a framework that facilitates patent retrieval for researchers, and
have integrated research papers and patents by analysing the citation relationships between them. We obtained cited research
papers in patents using two steps: (1) detection of sentences containing bibliographic information, and (2) extraction of
bibliographic information from those sentences. To investigate the effectiveness of our method, we conducted two experiments.
In the experiment involving Step 1, we prepared 42,073 sentences, among which a human subject manually identified 1,476 sentences
containing citations of papers. For Step 2, we prepared 3,000 sentences, in which the titles, authors, and other bibliographic
information were manually identified. We obtained a precision of 91.6%, and a recall of 86.9% in Step 1, and a precision of
86.2% and a recall of 85.1% in Step 2. Finally, we constructed an information retrieval system that provided two methods of
retrieving research papers and patents. One method was retrieval by query, and another was from the citation relationships
between research papers and patents. 相似文献
10.
Koreyoshi Imamura Kohshi Kinugawa Ryo Kagotani Mayo Nomura Kazuhiro Nakanishi 《Journal of food engineering》2012
Amorphous matrices made up of sugar molecules, are frequently used in food and pharmaceutical industries. A drawback to their use is that they are susceptible to collapse, as a result of water uptake and an increase in temperature and subsequently crystallize. Herein, the crystallization characteristics of amorphous sugar (sucrose and α-lactose) preparations were analyzed, with the purpose of obtaining knowledge that could lead to the prediction of how long the amorphous state is retained under various conditions. The impact of compression, physical aging and freezing rate on the induction period (tind) for crystallization were examined. Freeze-dried sugar samples were compressed at 74 or 443 MPa (5 min) and then rehumidified at specified RHs. Some freeze-dried sucrose samples were physically aged, and alternatively freeze-drying was conducted under different conditions. The isothermal crystallization of the prepared samples at different temperatures (T), the glass transition and the crystallization temperature (Tcry) were measured, using differential scanning calorimetry. The compression markedly decreased the tind, while significantly lowered the hygroscopicity. Physical aging and slower-freezing also shortened the tind. The tind was found to be correlated exclusively with (Tcry–T), regardless of rehumidification, compression, sugar type, physical aging and freezing rate in the freeze-drying process. 相似文献