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941.
The authors have already clarified that case-based reasoning (CBR) is very useful for the fault-restoration support system in electrical power networks. This paper describes the case-based construction method, adaptation and modification method of a case which is a fundamental process of CBR, and the results of evaluation. The following points were clarified through the simulations of fault restoration under various conditions with electrical power networks of practical scale: (1) a case-based construction method and the guide to the selection of cases which should be included in the case were made clear. Restoration plans which include many cases are registered in the base. Cases which would require long computation time are also registered in the case base. In the application which requires high-speed processing, such as fault restoration, there exists an optimum value in the total numbers of cases in the case base; (2) the function of load switching which is essential to perform adaptation and modification of a case flexibly was studied and embedded in the system herein. Inference power was augmented by the implemented of this function, and optimum for suboptimum solutions were obtained. Processing time with CBR is considerably shorter than other methods, and this feature is remarkable with complicated cases.  相似文献   
942.
Vanadate stimulates adipocyte 2-deoxyglucose transport and GLUT-4 translocation to the membrane through an insulin receptor-independent but wortmannin-inhibitable pathway. Vanadate stimulates PI 3-kinase in anti-IRS-1 immunoprecipitates and the binding between IRS-1 and the p85alpha subunit of PI 3-kinase. In insulin-resistant adipocytes from old rats vanadate fully stimulates IRS-1-associated PI 3-kinase, but partially activates glucose uptake. We conclude that: (a) vanadate stimulates 2-deoxyglucose uptake using a pathway that converges with that of insulin at the level of PI 3-kinase; and (b) adipocytes from old rats are defective in the insulin pathway at steps located both upstream and downstream of PI 3-kinase.  相似文献   
943.
The general utility of a method for determination of high-shear wet granulation end point by monitoring the wet granule particle size distribution was evaluated. Wet granulation was conducted in a 25-liter high-shear mixer using four model drugs with different solubilities and particle sizes (ethenzamide, unmilled and milled acetaminophen, and antipyrine). For each drug formulation, its wet granule particle size fraction and target range for granulation end point determination were selected based on the tablet characteristics that are known to be influenced by the wet granulation process. Granules manufactured under different conditions (i.e., different main and chopper blade speeds and binder supplying rate) but manufactured to the same granulation end point determined by the selected fraction and range showed very similar granule characteristics and subsequently very similar tabler characteristics. From the fact that there was a good correlation between the wet and dry-sized granule particle size distributions even if the drying method was changed from fluid-bed drying to vacuum drying, the general application of the end point determining method was verified. Further, the method was shown to be sensitive to the critical granulation parameters for granulation progression and to be very capable of determining the granulation extent. Thus, it was suggested that the method is applicable to various drugs and formulations for determination of wet granulation end point.  相似文献   
944.
The possibility of forecasting cloud-to-ground discharges is investigated. It is empirically well known that the cloud-to-ground discharges occasionally follow the cloud discharges, and the objective of this paper is to determine if it is true or false, using the SAFIR data for a few years. Since the development of thunderclouds is determined by the movement of its active area, the coordinate fixed to the moving thunderclouds is applied for analysis. The analyzed results suggest that forecasting cloud-to-ground discharges with 10-min advance notice for both summer and winter thunderstorms is a possibility.  相似文献   
945.
We have reported that chemical modification of tumor necrosis factor-alpha (TNF-alpha) with polyethylene glycol (PEG) markedly increases its antitumor potency without any adverse side effects. MPEG-TNF-alpha, especially, in which 56% of the lysine amino groups of TNF-alpha are coupled with PEG, exhibits 100-fold more antitumor activity in vivo than native TNF-alpha in the Meth-A murine sarcoma model. In this study, we investigated the pharmacokinetics of PEG-modified TNF-alpha with various molecular sizes to clarify the mechanisms of the enhanced antitumor potency of MPEG-TNF-alpha. The plasma half-lives of modified TNF-alpha increased with increasing molecular size. The decreased plasma clearance of modified TNF-alpha was partially caused by the shielding effect of the proteolytic sites in TNF-alpha by the attached PEG and the decreased transport from blood to various tissues. Almost all native TNF-alpha was uniformly distributed to the kidney and reticuloendothelial system within 1 hr of an intravenous administration, and rapidly disappeared from these tissues at 3 hr. However, very little native TNF-alpha was transported into the tumor. The absolute distributed amount and distribution profile of modified TNF-alpha to tissues other than the tumor were the same as those of native TNF-alpha, whereas the plasma levels of the modified TNF-alpha were higher than plasma levels of the native TNF-alpha. The tumor distribution of modified TNF-alpha was markedly enhanced compared with native TNF-alpha and gradually increased over time. About 9-fold more MPEG-TNF-alpha was distributed to the tumor than native TNF-alpha. Thus, we found that the marked increase in the antitumor potency of PEG-modified TNF-alpha resulted from the enhanced blood residency and tumor accumulation. The antitumor effect of MPEG-TNF-alpha against sarcoma-180 other than Meth-A fibrosarcoma was also about 100 times greater than that of native TNF-alpha when systemically administered. The optimal PEGylation of TNF-alpha facilitated its antitumor potency and MPEG-TNF-alpha may be useful systemic antitumor therapeutic drug.  相似文献   
946.
Dibenzoylhydrazines are the nonsteroidal ecdysone agonists. Using comparative molecular field analysis, we previously found that the alkyl side chain of 20-hydroxyecdysone (20E) is three-dimensionally superposable with one of their two aryl moieties. To identify the aryl moiety that is better superposable on the alkyl chain, we synthesized compounds in which one of the two aryl groups of tebufenozide (N-t-butyl-N-3,5-dimethylbenzoyl-N'-4-ethylbenzoylhydrazine) is replaced by alkyl groups such as C4H9, C5H11, and C6H13. The molting hormonal activity of these compounds was measured using cultured integuments prepared from rice stem borers, Chilo suppressalis Walker, in terms of stimulation of incorporation of N-acetyl-[14C]glucosamine. N-t-Butyl-N-3,5-dimethylbenzoyl-N'-acylhydrazines with a hexanoyl or heptanoyl group were about 20-fold higher than that of 20E, whereas N-acyl-N-t-butyl-N'-4-ethylbenzoylhydrazines with a hexanoyl or heptanoyl group were much weaker than 20E. Their larvicidal activity was also measured against rice stem borers. The former series of compounds were much more active than the other series as well as 20E. Thus, the benzoyl moiety of dibenzoylhydrazines, which is bound to the secondary nitrogen atom (-NH-), is replaceable by aliphatic acyl groups without greatly affecting the biological activities.  相似文献   
947.
The biological rhythm of females is closely related to the menstrual cycle, and this rhythm is believed to influence circadian changes in body temperature. This study investigated and compared the patterns of circadian changes in the body temperature of healthy adult females and patients suffering from premenstrual syndrome or major depression. Body temperature was measured both rectally and sublingually in healthy subjects, and only sublingually in the patients. During the luteal phase in healthy adult females, both the average and lowest nocturnal body temperatures increased, the amplitude of the circadian changes decreased, and the times of the lowest and highest temperatures within a 24-hour period were delayed by 2-3 h. In the patients, the amplitude decreased during disease periods, especially in the follicular phase, whereas in the luteal phase, circadian changes showed great variation each day, although the decrease in amplitude was not as remarkable. The results show that (i) the biological rhythm of females is intrinsically unstable in the luteal phase, although this rhythm is stable in the follicular phase; and, (ii) symptoms were often aggravated with the decreases in amplitude experienced in the luteal phase.  相似文献   
948.
Yasuhito Nakagawa 《Lipids》1993,28(11):1033-1035
A paired-ion high-performance liquid chromatographic (HPLC) procedure was developed for the separation of individual molecular species of phosphatidylinositol (PI) without prior derivatization. The separation is accomplished on a reverse-phase column using acetonitrile, methanol and 10 mM tetrabutylammonium phosphate as mobile phase. Separation of the major molecular species of soybean PI by HPLC is achieved within 60 min. The method is applicable to analytical and metabolic studies on PI and has the advantage that the entire PI structure is preserved, as no degradation or derivatization procedures are involved.  相似文献   
949.
950.
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