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41.
KS Ghenghesh AS Altomi A Elgrari MR Alosta Omar AM Sharif Eddin SS Abied 《Canadian Metallurgical Quarterly》1995,72(1-2):13-15
Twenty seven Aeromonas strains (5A. hydrophila, 8A. sobria and 14A. caviae) isolated from children with diarrhoea and 34 Aeromonas strains (9A. hydrophila, 7A. sobria an 18A. caviae) isolated from children without diarrhoea were tested from haemolysin production. The results obtained showed that haemolysin production using human, horse or sheep erythrocytes was significantly associated with A.hydrophila and A sobria but not with A.caviae, regardless of whether these strains were isolated from children with or without diarrhoea. Human or horse rather than sheep erythrocytes are recommended for use in the haemolysin assay. 相似文献
42.
Arylalkynes such as 4-phenyl-1-butyne (PBY), 5-phenyl-1-pentyne (PPY) and 2-ethynylnaphthalene (2-EN) are suicide inhibitors of cytochrome P450 enzymes. Arylalkyl isothiocyanates such as 6-phenylhexyl isothiocyanate (PHITC) are structurally related to arylalkynes and are known to inhibit the cytochrome P450 mediated metabolic activation and tumorigenicity of a tobacco-specific lung carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In this study, we compared the ability of PBY, PPY, 2-EN and PHITC to inhibit A/J mouse lung tumorigenesis by NNK. Groups of 20 female mice were gavaged with 5 mumol of arylalkyne or PHITC in corn oil. Two hours later they were given a single i.p. injection of 10 mumol NNK. The mice were killed 16 weeks later. PPY and PHITC were both potent inhibitors of tumorigenesis by NNK, reducing lung tumor multiplicity from 8.35 tumors per mouse to 0.40 and 0.35 respectively. PBY and 2-EN also significantly inhibited tumor multiplicity. The results of this study demonstrate that arylalkynes and PHITC are potent inhibitors of NNK induced lung tumorigenesis in A/J mice, consistent with the hypothesis that inhibition of specific cytochrome P450 enzymes is involved in inhibition of tumorigenesis. 相似文献
43.
Y. Ohshima H.S. Ahn M. Aoki S. Awa M. Fukushima H. Hayashii X.Q. Hu T.W. Hur S. Igarashi H. Ikeda H.C. Jeong K. Kaneyuki D.Y. Kim S.K. Kim A. Kuzmin M.H. Lee S. Noguchi A. Ochi H. Sagawa N. Sato N. Sugiyama K. Tamai T. Tanimori N. Toomi T.J. Wang K. Watanabe Y. Watanabe X.C. Zhong Y.C. Zhu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):517-523
We studied the performance of a prototype electromagnetic calorimeter for the BELLE detector at the KEK proton synchrotron for an energy range of 0.25–3.5 GeV. The prototype consisted of an array of 6 × 5 CsI(Tl) crystals with 30 cm length (16.2 radiation lengths) and about 6 cm × 6 cm cross section. The scintillation light of each CsI(Tl) crystal was read out by two large-area PIN photodiodes and charge-sensitive preamplifiers attached at the rear face of the crystal. We measured the energy and position resolution for electrons and the e/π separation for two sets of matrix configurations: one corresponded to the center and the other to the edge of the barrel calorimeter. The overall performance measured by the test proves that the prototype calorimeter is satisfactory for the use in the BELLE detector. 相似文献
44.
AG Martov VIa Simonov BM Krendel'' SS Zenkov SA Moskalenko 《Canadian Metallurgical Quarterly》1993,38(3):16-19
Hyperferremia is shown to affect antioxidant system of the body, oxidation-reduction reactions in the cells seen as shifts in lymphocyte chemiluminescence. Dynamic changes in lymphocyte chemiluminescence reflect the level of hyperferremia. 相似文献
45.
JR Perry SS Deodhare JM Bilbao D Murray P Muller 《Canadian Metallurgical Quarterly》1993,32(2):157-162
Sex hormones have profound effects on immune responses and may influence the outcome of autoimmune diseases such as rheumatoid arthritis (RA). We investigated the effect of gonadal steroids on the production of interleukin-1 (IL-1) and IL-6, cytokines believed to be important in the pathogenesis of RA. Peripheral blood mononuclear cells (PBMCs) were isolated from healthy male donors and male patients with RA, and were stimulated with lipopolysaccharide (LPS) in the presence of different concentrations of 17-beta-estradiol, progesterone or testosterone. In studies of cells from normal male donors, 17-beta-estradiol at pharmacological concentrations (> or = 10(-6) M) enhanced IL-1 and IL-6 secretion as well as the production of cell-associated IL-1. Progesterone and testosterone at similar concentrations inhibited IL-1 secretion but had no significant effect on IL-6 secretion or on the production of cell-associated IL-1. In studies of male RA donors, 17-beta-estradiol failed to enhance IL-1 or IL-6 secretion and progesterone failed to inhibit IL-1 secretion. The inhibitory effects of testosterone, however, appeared to be similar to that in normal donors. It is suggested that 17-beta-estradiol may promote IL-1 and IL-6 production and release, while gestation hormone, progesterone, and testosterone may inhibit IL-1 release in vivo. These data may partly explain the gender and age differences in the incidence of RA and the development of the disease in men with low and androgen levels. 相似文献
46.
Robotic synthesis is making possible the synthesis of large, systematically designed sets of compounds. We analyze a 512-compound set that is a 2(9) full factorial experimental design using a recursive partitioning algorithm, FIRM, and a high-dimension visualization tool, TempleMVV. These techniques are used to quickly and easily identify the main trends in the data set and also identify unusual observations. We show that analytical and visualization methods can be used synergistically to analyze a large, complex, high-dimensional data set. We also show that a fractional factorial design of 128 compounds would give essentially the same information. 相似文献
47.
The base station (BS) in the CDMA Mobile System (CMS) connects calls through the radio interface and is designed to provide mobile subscribers with high quality service in spite of mobile subscribers’ motions. The BS consists of multiple base station transceiver subsystems (BTSs), a base station controller (BSC) and a base station manager (BSM). This paper is concerned with the BSC and the BSM. The BSC is located between the BTSs and the mobile switching center (MSC) connected with the public network, and is responsible for controlling mobile calls from and to mobile subscribers via the BTSs. The BSM provides operator-interfaces per the BS and takes responsibility of operation and maintenance (OAM) of the BS. Design of the BSC is based on two module types: functional module and unit module. The functional module is used to support new services easily and the unit module to increase the system capacity economically. Both modular types are easily achieved by inserting the corresponding modules to the system. Particularly, in order to efficiently support the soft handover which is one of CDMA superior advantages, the BSC adopts a large high-speed packet switch connecting up to 512 BTSs, and thus mobile subscribers can be provided with soft handover in high probability. The BSM is based on a commercial workstation to support OAM functions efficiently and guarantee high reliability of the functions. The BSM uses graphical user interface (GUI) for efficient OAM functions of the BS. 相似文献
48.
49.
Cardioprotective effects of a standardized extract from leaves with flowers of Crataegus (WS-1442; content of oligomeric procyandins [OPC]: 18.75%) have recently been demonstrated in an ischemia-reperfusion model in rats. Further studies were now conducted to clarify the mechanism of action and to identify active constituents involved in these effects of WS-1442. Exhausting partitioning between ethyl acetate/water and successive ultrafiltration of the aqueous layer led to the quantitative recovery of three fractions, which were tested for their in vitro radical scavenging (RS) and human neutrophil elastase (HNE) inhibitory activity. The lipophilic ethylacetate-soluble fraction A, enriched in flavone derivatives and constituting 14.9% of WS-1442, was as active as WS-1442 in inhibiting HNE. However, its RS activity was only about half that of the primary extract. Although 67.9% of WS-1442 was recovered in a water-soluble low molecular weight fraction B, this fraction displayed only weak RS and HNE inhibiting activity. In contrast, the RS and HNE inhibiting potencies of an essentially flavone-free and OPC-rich fraction C (21.3% of WS-1442) were significantly higher (inhibition of lipid peroxidation: IC50 0.3 microgram/ml; inhibition of HNE: IC50 0.84 microgram/ml) as those of WS-1442. The RS and HNE inhibitory activities of the extract and those of its fractions correlated well with their OPC-content but not with their concentration of flavonols. These results demonstrate that OPCs of Crataegus extracts possess stronger radical scavenging activities than flavone derivatives or other constituents. In addition, the oligomeric components are potent inhibitors of HNE. Oral administration of 20 mg/kg/d of the OPC-rich fraction C to rats afforded similar protection against ischemia-reperfusion induced pathologies as treatment with WS-1442 at a dose of 100 mg/kg/d. These observations indicate that radical scavenging and elastase inhibitory activities could indeed be involved in the observed cardioprotective effects of WS-1442, and demonstrate that OPCs are major orally active constituents of WS-1442. Thus, Crataegus extracts used therapeutically for cardiovascular diseases should be analyzed and standardized for their OPC-content. 相似文献
50.