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51.
Circulating immune complexes in the sera of patients with confirmed histological diagnosis of carcinoma of the prostate, were found to interfere in the sensitized leukocyte's in vitro reactivity to prostate cancer associated antigen as evaluated by tube leukocyte adherence inhibition assay, thereby suggesting an inhibitory role of such serum factors in host's anti tumor cell mediated immune responses. 相似文献
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Kuris AM Hechinger RF Shaw JC Whitney KL Aguirre-Macedo L Boch CA Dobson AP Dunham EJ Fredensborg BL Huspeni TC Lorda J Mababa L Mancini FT Mora AB Pickering M Talhouk NL Torchin ME Lafferty KD 《Nature》2008,454(7203):515-518
Parasites can have strong impacts but are thought to contribute little biomass to ecosystems. We quantified the biomass of free-living and parasitic species in three estuaries on the Pacific coast of California and Baja California. Here we show that parasites have substantial biomass in these ecosystems. We found that parasite biomass exceeded that of top predators. The biomass of trematodes was particularly high, being comparable to that of the abundant birds, fishes, burrowing shrimps and polychaetes. Trophically transmitted parasites and parasitic castrators subsumed more biomass than did other parasitic functional groups. The extended phenotype biomass controlled by parasitic castrators sometimes exceeded that of their uninfected hosts. The annual production of free-swimming trematode transmission stages was greater than the combined biomass of all quantified parasites and was also greater than bird biomass. This biomass and productivity of parasites implies a profound role for infectious processes in these estuaries. 相似文献
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Mark R. Shaw 《Journal of Natural History》2017,51(19-20):1119-1149
The small plurivoltine moth Anthophila fabriciana is widespread and often abundant in Britain wherever its main larval foodplant, stinging nettle, occurs. It overwinters as a larva (first generation) then has one or more partly overlapping summer broods (notionally second generation). A total of 5017 larvae were collected and reared from widely distributed populations in Britain, and the resulting 2167 host mortalities due to parasitoids were assessed. Small collections of pupae were also made. Altogether 25 parasitoid species, including secondary parasitoids, were found. Larval parasitism was heaviest in the second generation. In each generation there was a dominant parasitoid that was absent from the other. Summary information on the developmental biology and host range (expressed quantitatively and resulting from very broad rearing programmes) for each parasitoid is given. They are classed as ‘absolute specialists’, ‘taxon oligospecialists’, ‘niche oligospecialists’, ‘niche generalists’, ‘casuals’ and ‘strays’. Both kinds of oligospecialists can be ‘paraspecialists’ if only one potential host occurs locally. Although constructing a quantitative food web is not appropriate, providing both source web and sink web data in quantitative form enables the parasitoid complex to be understood in the wider context of the ecosystem, necessary for both biodiversity and nature conservation interests. In Appendix 1, parasitoids reared from other European Choreutidae are listed quantitatively. 相似文献
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G. Shaw B. M. Smallwood F. C. Steward 《Cellular and molecular life sciences : CMLS》1968,24(11):1089-1090
Zusammenfassung Die 3-, 7- und 9-Monomethylderivative des Cytokinins Zeatin wurden hergestellt und ihre Aktivität in der Karottenwurzel nachgewiesen. Die Ergebnisse zeigen, dass die Nukleotidderivative nicht not-wendige Stufen im Wirkungsmechanismus darstellen. 相似文献
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G. Shaw B. M. Smallwood D. V. Wilson 《Cellular and molecular life sciences : CMLS》1967,23(7):515-518
Zusammenfassung Zeatin-ribosid-5-phosphat wurde einerseits durch Umsetzung von 6-Chlorpurin-ribotid mit trans-4-Amino-2-methylbuten-(2)-ol-(1) und andererseits durch Behandlung von Isopropyliden-zeatin-ribosid mit Pyrophosphorylchlorid hergestellt. Die Phosphorylierung des Isopropylidenderivats in Pyridin ergab ein Allylpyridiniumderivat, dessen Struktur spektroskopisch und durch Abbau bewiesen wurde. 相似文献
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Effect of prolonged exercise on platelet adhesiveness 总被引:5,自引:0,他引:5
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