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Just Words: Law, Language, and Power. John M. Conley and William M. O'Barr. Chicago: The University of Chicago Press, 1998. 168 pp.  相似文献   
7.
The effect of the polyamine, spermidine, on formyl-methionyl-leucyl-phenylalanine stimulated hydrolysis of polyphosphoinositides was examined in purified human neutrophils by measurement of inositol phosphate production from radioactively labelled inositol. Spermidine inhibited formyl-methionyl-leucyl-phenylalanine stimulated inositol phosphate production by neutrophil in a dose dependent manner. Inhibition of formyl-methionyl-leucyl-phenylalanine stimulated inositol phosphate accumulation by spermidine was maximal at 10 microM and the IC50 value for this effect was 4.2 microM spermidine. This action of spermidine, thought to be mediated by a membrane component other than phospholipase C, may reflect a control mechanism modulating the response of the polyphosphoinositide system.  相似文献   
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Serum neutralizing antibodies against the human immunodeficiency virus were frequently detected in infected individuals, and low or absent serum neutralizing titers correlated with poor prognosis. Multiple diverse human immunodeficiency virus isolates were found to exhibit similar susceptibility to neutralization by a panel of human seropositive sera, suggesting that neutralizing antibodies are largely directed against conserved viral domains. Furthermore, utilizing antisera raised against a library of synthetic env peptides, four regions which are important in the neutralization process have been identified within both human immunodeficiency virus envelope glycoproteins (gp41 and gp120). Three of these are in conserved domains and should be considered for inclusion in a candidate vaccine.  相似文献   
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Formation of lipoxin A by granulocytes from eosinophilic donors   总被引:3,自引:0,他引:3  
The formation of arachidonic acid-derived lipoxygenase products was examined with human granulocytes obtained from eosinophilic donors. These eosinophil-enriched leukocyte populations, challenged in vitro with the ionophore of divalent cations A23187, transformed both exogenous and endogenous sources of arachidonic acid to several lipoxygenase-derived products, including 5(S), 6(R),15(S)-trihydroxy-7,9,13-trans-11-cis-eicosatetraenoic acid (lipoxin A). Lipoxin A was detected and characterized by high-pressure liquid chromatography (HPLC), ultraviolet absorbance, and gas-liquid chromatography-mass spectroscopy. Neither lipoxin B nor 6(S)-LXA was consistently detected in extracts from these incubations. The amounts of lipoxin A formed were proportional to the percentage of eosinophils present in the suspension. The results indicate that granulocytes from eosinophilic donors can generate lipoxin A.  相似文献   
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Although the effect of vaginal tampons on the microbial flora during menstruation has recently been studied by several investigators, quantitative effects attributable to particular tampon fibers have received less attention. The purposes of the present study were (i) to determine and then to compare the effects of polyacrylate rayon tampons and viscose rayon tampons on the normal vaginal flora, (ii) to compare quantitative bacterial counts obtained from these tampons with those obtained from concomitant vaginal swabs, and (iii) to determine whether either of these tampon types alters the vaginal microflora when compared with the microflora in the same women using all-cotton tampons or external catamenial pads. Tampon and swab samples were obtained at predetermined times from 18 women for an average of seven menstrual cycles. Samples consisting of swabs from women wearing menstrual pads were compared with swab and tampon samples taken at predetermined times during the menstrual cycle from women using cotton, polyacrylate rayon, or viscose rayon tampons. Samples were analyzed for total aerobic, facultative, and anaerobic bacterial counts. Statistical evaluation of the results indicated that, on the whole, total bacterial counts decreased during menstruation and that the numbers of bacteria in tampons tended to be lower than those in swab samples taken at the same time. The tampon type had little effect on the vaginal microflora.  相似文献   
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