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991.
992.
The object-oriented approach to integrating knowledge data, and models is examined. Under the object-oriented paradigm, everything is an object, which is itself an encapsulation of data and methods to manipulate and access the data within the object. Thus knowledge, data, and models can be defined as special kinds of objects. Active knowledge/data language (KDL), a functional object-oriented database system is considered, covering the active-KDL-type system and functions, and query-driven simulation 相似文献
993.
994.
995.
AM-1155 is a newly synthesized 6-fluoro-8-methoxy quinolone. We assessed its in vitro antimycobacterial activity using sparfloxacin (SPFX) and ofloxacin (OFLX) as comparison drugs. The MICs of these agents for various mycobacterial strains were determined by the agar dilution method with 7H11 medium. AM-1155 had lower MICs for 50 and 90% of tested strains of Mycobacterium kansasii, M. marinum, and M. fortuitum-M. chelonae complex than SPFX and OFLX, and the values for M. tuberculosis, M. scrofulaceum, and the M. avium-M. intracellulare complex were similar to those of SPFX and considerably lower than those of OFLX. In addition, the antimicrobial activity of AM-1155 against M. tuberculosis and M. intracellulare phagocytosed into murine peritoneal macrophages was compared with that of OFLX. AM-1155 (1 microgram/ml) inhibited the intracellular growth of both M. tuberculosis and M. intracellulare, whereas OFLX at the same concentration failed to show any such effect. Moreover, AM-1155 (10 micrograms/ml) exhibited a steady bactericidal action against M. tuberculosis, whereas OFLX at the same concentration had only a weak effect. AM-1155 (10 micrograms/ml) also inhibited the growth of M. intracellulare more effectively than OFLX. 相似文献
996.
Replies to R. E. Roughton's (see record 1994-27310-001) response to D. K. Flaks's (see record 1993-23357-001) article on homophobia and the psychologists's role in psychoanalytic training institutes. Flaks commends attempts by the American Psychoanalytic Association to combat homophobia within the organization but notes potential problems that might limit its success. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
MH Maslowska AD Sniderman LD MacLean K Cianflone 《Canadian Metallurgical Quarterly》1993,34(2):219-228
The initial suspicion that obesity increases coronary risk has been much sharpened with the demonstration that risk is more tightly linked to abdominal than to peripheral obesity, and tighter yet again when the mass of omental adipose tissue is taken into account. These data suggest that important metabolic differences might exist between adipocytes from different regions, and indeed, it has long been appreciated that triacylglycerol hydrolysis can be stimulated to a greater extent in omental than in subcutaneous adipocytes. The present study focuses on triacylglycerol synthesis in human subcutaneous and omental adipocytes, a process which, by contrast, has received relatively little attention. Experiments were done on adipose tissue removed at laparotomy and on cultured preadipocytes. With the former, triacylglycerol synthesis was measured in the presence and absence of oleate added to the medium using radiolabeled glucose and oleate as tracers. The results demonstrate that under all conditions examined triacylglycerol synthesis in subcutaneous adipose tissue exceeded that in deep omental adipose tissue. To study the cells in more detail, preadipocytes were cultured and triacylglycerol synthesis was examined again under basal conditions and with stimulation with insulin and acylation stimulating protein (ASP). Under basal conditions, particularly when oleate was added to the medium, clear differences were present such that triacylglycerol synthesis was substantially greater in subcutaneous preadipocytes than in omentally derived preadipocytes. These differences were more pronounced when the cells were stimulated with either insulin or acylation stimulating protein. Overall, triacylglycerol synthetic capacity in subcutaneous tissue exceeded that in omental tissue. As a consequence, omental tissue as compared to subcutaneous adipose tissue would have a limited capacity to prevent fatty acids from reaching the liver and stimulating hepatic lipoprotein synthesis. 相似文献
998.
Cortical blood flow (CoBF) was measured continuously by the laser-Doppler method to evaluate the effect of hypercapnia on cortical blood flow during ten surgical procedures in ten young patients (mean +/- SD 9.3 +/- 6.4 yr) with Moyamoya disease. The CoBF was 42.8 +/- 13.4 (ml.100 g-1.min-1) during normocapnia (PaCO2 = 39.0 +/- 2.4 mmHg), and 38.7 +/- 14.4 during hypercapnia (PaCO2 = 47.1 +/- 2.5 mmHg). There was a decrease in CoBF with hypercapnia (P < 0.05) so that the normal CoBF response to hypercapnia was impaired during surgery in the patients with Moyamoya disease. He concluded that patients with Moyamoya disease have a precarious cerebral circulation and hypercapnia may be detrimental to the cortical circulation. This suggests that normocapnia is preferable to hypercapnia in patients with Moyamoya disease during anaesthesia. 相似文献
999.
Time variation of drinking is substantial and has an effect on aggregate estimates of consumption. In this article it is shown that because of a considerable seasonal variation in consumption (+/- 20%) a serious bias in annual consumption estimates can be expected in surveys with a limited time frame. The present study analyzes drinking data collected in the general population of the Netherlands from March 1985 through December 1985 (including Christmas and New Year's Eve). Since it was expected that sensitivity to temporal fluctuations might not be equal for different methods of measurement, several indices of consumption were compared. Although the assessed seasonal effect varies indeed across types of measurement, across male and female subsample and across types of alcoholic beverage, the general tendency is for consumption to be highest in the spring season and lowest in the autumn. Sales figures fluctuate accordingly. It is evident that the risk of biased estimates is larger the shorter the time frame of the survey. Seasonal variation was highest in the frequency domain. Furthermore, exclusion from the time frame of collective holidays, during which people drink more often and more per occasion (viz., Christmas), increases the risk of biased estimates. Even estimates of abstention, but also regular heavy drinking among women, appear to vary considerably over the three seasons in this study. The main conclusion is that results of comparisons of survey data on drinking, particularly those over time, are more or less invalid if the respective time frames of the surveys do not correspond. 相似文献
1000.
The concept of a nonaxisymmetrical X-ray image intensifier is presented in this paper. Instead of cylindrical electrodes, as in the conventional device, this intensifier is equipped with planar electrodes. Each one consists of some number of elementary quadrilateral patches, which are mutually insulated from each other and supplied with the proper voltages. The algorithm for determining potentials which must be supplied to the elementary electrodes is described in the paper. The algorithm has been validated by comparing the electric field distributions in both configurations. Details of the electric field distribution are also helpful in evaluating the optical characteristics of the intensifier 相似文献