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Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast.  相似文献   
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Pyrochlores of A1?xHxTaO3·nH2O (A=Na,K) were prepared under the hydrothermal conditions. The values of x for these compounds were increased from 0.3 to 0.5 for A=Na and from 0.2 to 0.5 for A=K by treatment with the distilled water. The compounds with x<0.5 were decomposed to a mixture of NaTaO3 and Na2Ta4O11 for A=Na, or to a mixture of KTaO3 and a tetragonal tungsten bronze phase, and those with x=0.5 to a single phase of A2Ta4O11 at elevated temperatures. Below the decomposition temperatures, defect pyrochlores with oxygen vacancies, A1?xTaO3?x2, were produced. They were hygroscopic, and in the case of A=K and x=0.5 the original phase was recovered by leaving in air for several hours.  相似文献   
5.
Fumio Negoro 《Knowledge》2003,16(7-8):383-397
The purpose of our study is to build up relationships between requirement and source programs with our originally thought-out rules. When other rules to be derived from these original rules are applied to software development, even a single instruction in a programming language could be determined, and the program would satisfy the requirement. More specifically speaking, these rules will turn into a formula or a prototype of software programs. Hence, when the variables in the requirement are placed in the formula, we can get a required program in an automatic way.  相似文献   
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Epstein-Barr virus (EBV) has been implicated as a causal virus of gastric cancer with episomal monoclonality, elevated antibodies and a unique morphologic expression in the early intramucosal stage, but the infection mechanisms have not been demonstrated. EBV has been shown only in the cancerous lesions by the highly sensitive EBV-encoded small RNA in situ hybridization (EBER-ISH) method, not in the dysplastic mucosa adjacent to the cancer. A case is presented of multiple EBV-positive gastric cancer and dysplastic epithelium observed in a 52-year-old man. Serial cut sections of the gastrectomy specimen showed four small cancerous lesions, three of which were EBER-positive, and three EBER-positive, minute, non-cancerous dysplastic lesions. The three cancerous lesions were intramucosal cancer, with one having minimal submucosal invasion forming a lymphoepithelioma-like histology. All of these EBER-positive cancerous and dysplastic lesions showed intense CD8 T-lymphocytic infiltration. There was no such findings in the EBV-negative cancerous lesion. It was concluded that EBV infection may occur in the epithelial cells of atrophic gastric mucosa, and progress to cancer with monoclonal expansion through the EBV-positive dysplastic change. Cytotoxic T-lymphocytic reactions can occur even in the dysplastic lesions. Multifocal EBV infection in the gastric mucosa may occur and, if necessary, total gastrectomy is recommended in such a case.  相似文献   
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We report on a case of adenovirus hemorrhagi cystitis that developed in a 49-year-old woman during intensive chemotherapy for adult T-cell leukemia. Although rapid etiologic diagnosis is essential for the effective management of viral hemorrhagic cystitis, the isolation of adenovirus from urine is often too time-cousuming. We detected the adenovirus antigen in the patient's urine using an Adenoclone direct sandwich ELISA kit (Cambridge Bio Science), which is commonly employed for the diagnosis of adenovirus conjunctivitis. Treatment consisted of intravenous vidarabine and bladder irrigation, which resulted in prompt clinical improvement. The Adenoclone kit was useful for the rapid etiologic diagnosis of adenovirus hemmorrhagic cystitis.  相似文献   
8.
Respiratory infections are the most common infection in children. They differ remarkably according to age, bacteria and viruses. Therefore a careful history of outbreak, age, former infections, involvement of surroundings, symptoms, etc are essential. The present study included 50 children, aged between 0.3 and 12 yrs, all treated ambulatorily. 21 received brodimoprim (B) and 29 erythromycin (E). Indications were: tonsillitis, bronchitis, otitis media, sinusitis and scarlet fever. Dosages were: B was given 10 mg/kg body weight (b.w.) initially followed by 5 mg/kg b.w., once-a-day. The duration of treatment varied between 4 and 14 days (mean 8.3 days). E was given 30.50 mg/kg b.w. 3 times per day; duration 4 to 14 days (mean 8.6 days). Overall results were: in group B:12 cures, 5 improvements, 3 failures; 1 not assessable. In group E: 20 cures, 8 improvements, 1 failure. Side effects: in group B: vomiting (1), skin reaction (2), discontinuation (2); in group E: skin reaction (1), diarrhea (5), diarrhea+vomiting (1); discontinuation (2). The differences in efficacy and tolerability in the two groups are not statistically significant. The improved compliance with a single versus t.i.d. dosages has to be taken into account.  相似文献   
9.
People faced with an unfamiliar product or service tend to fall back on mental models based on analogical relationships with familiar products or services. Two experiments on the analogical relationships or metaphors that people might use when operating a communications terminal are described. In the first experiment, the role previously acquired operating knowledge has in determining the mental models people use when directory dialing with novel equipment is examined. In a second experiment, it is shown that an explicit appeal to an analogy between conventional mail and electronic mail can help users learn to use an electronic mail system, and make it easier for them to remember how to use the system as long as 90 days after initial exposure. It is concluded that the mental model is constructed only from the user's operating knowledge acquired as a result of past experiences, and the metaphor method is effective when the instructions are metaphorically taught  相似文献   
10.
This paper presents the robust control design of a magnetic suspension system for a flexible beam which is a simplified model of an elastic rotor in a magnetic bearing system. To stabilize this magnetic suspension system which is unstable in nature, the Hinfin; control theory is applied for a design of the control system. To apply the Hinfin; control theory, a statespace model of an augmented plant with frequency-weighting functions is constructed. This augmented plant has two inputs which are the exogenous inputs and the control inputs, and two outputs which are the sensor outputs and the regulated outputs. Here we consider the mixed sensitivity problem. The Hinfin; controller is implemented by a digital controller which is able to execute the computations very quickly. For the evaluation of the control performance, several experiments are made. The robustness of the closed-loop system is confirmed by the experimental results. The result of this study is useful for the control design of a magnetic bearing system.  相似文献   
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