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Several prototype macrophage (MO) populations were compared for differences in ectoenzyme phenotype and polyamine content. Resident peritoneal MO and Corynebacterium parvum (CP)-activated peritoneal MO expressed unique ectoenzyme phenotypes, while bone marrow derived MO (BMDMO), obtained from stem cells after 7 days in culture with colony stimulating factor, and thioglycollate (TG)-elicited peritoneal MO exhibited a similar ectoenzyme phenotype. All of the MO populations, however, differed in polyamine accumulation patterns. These results suggest that ectoenzyme phenotypes do not serve as completely selective markers of MO differentiation. Moreover, BMDMO do not resemble steady state tissue peritoneal MO but appear to resemble inflammatory MO in several respects. Therefore activated BMDMO do not appear to provide an accurate model system for their continued use in studies to characterize the development of resident tissue MO.  相似文献   
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The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from nucleotide sequence variation across a 765-bp region in the cytochrome oxidase I and II genes of the mitochondrial genome. Most parsimonious relationships of 25 haplotypes from 16 Greya species and two outgroup genera (Tetragma and Prodoxus) showed substantial congruence with the species relationships indicated by morphological variation. Differences between mitochondrial and morphological trees were found primarily in the positions of two species, G. variabilis and G. pectinifera, and in the branching order of the three major species groups in the genus. Conflicts between the data sets were examined by comparing levels of homoplasy in characters supporting alternative hypotheses. The phylogeny of Greya species suggests that host-plant association at the family level and larval feeding mode are conservative characters. Transition/transversion ratios estimated by reconstruction of nucleotide substitutions on the phylogeny had a range of 2.0-9.3, when different subsets of the phylogeny were used. The decline of this ratio with the increase in maximum sequence divergence among taxa indicates that transitions are masked by transversions along deeper internodes or long branches of the phylogeny. Among transitions, substitutions of A-->G and T-->C outnumbered their reciprocal substitutions by 2-6 times, presumably because of the approximately 4:1 (77%) A+T-bias in nucleotide base composition. Of all transversions, 73%-80% were A<-->T substitutions, 85% of which occurred at third positions of codons; these estimates did not decrease with an increase in maximum sequence divergence of taxa included in the analysis. The high frequency of A<-->T substitutions is either a reflection or an explanation of the 92% A+T bias at third codon positions.   相似文献   
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Comparison of antiviral and antitumor activity of activated macrophages.   总被引:5,自引:0,他引:5  
The antiviral and antitumor activity in vitro of normal, stimulated, vaccinia virus “immune”, and activated peritoneal macrophages were compared. Activated (pyran or corynebacteria induced) PEC exhibited both antitumor and antiviral activity. Stimulated (thioglyocollate) and vaccinia virus “immune” PEC inhibited virus growth but did not possess antitumor activity. Normal (unstimulated) PEC were relatively ineffective in either activity. The antiviral activity was nonspecific, being expressed against herpes simplex and EMC viruses in addition to vaccinia. Although a possible role for interferon was suggested by the lack of activity of mouse PEC on vaccinia virus growth in heterologous FLK cells, definitive proof was not obtained. The activity was most pronounced against multiple cycles of viral infection initiated at a low multiplicity of infection. Single cycle virus growth was not affected, suggesting that the major inhibition was on subsequent cycles of virus growth.  相似文献   
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