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561.
562.
Brandt Ingvar Högman Per-Gunnar Larsson Ywonne Olsson Sten 《Acta veterinaria Scandinavica》1978,19(3):368-376
Whole-body autoradiography of DDT-14G, 2,2′,4,5′-tetrachlorobiphenyl-14G and 2,2′,3,3′,4,4′,5,6′-octachlorobiphenyl-14C in laying quails indicated a strong deposition of radioactivity in the yolk of the growing follicles and the egg, confirming this to be a significant excretion route of lipophilic environmental pollutants in laying birds. A specific uptake of DDT and octachlorobiphenyl, but not of tetrachloro-biphenyl, was observed in the cortical cords of the adrenals. The octachlorobiphenyl was concentrated also in the ovarian stroma. Both DDT and the tetrachlorobiphenyl were excreted in the bile juice to the small intestine. No such excretion of octachlorobiphenyl was observed, indicating its rate of metabolization to be low. All compounds were accumulated and stored in the body fat. A previously described specific accumulation of 2,2′,4,5′-tetrachlorobiphenyl in the respiratory tract of mice was not observed in the quail. 相似文献
563.
564.
CLADISTICS AND FAMILY LEVEL CLASSIFICATION OF THE GENTIANALES 总被引:1,自引:0,他引:1
Lena Struwe Victor A. Albert Birgitta Bremer 《Cladistics : the international journal of the Willi Hennig Society》1994,10(2):175-206
Abstract— The most recent classification of the angiosperm order Gentianales (Thorne, 1992) includes four principal families: Apocynaceae, Gentianaceae, Loganiaceae, and Rubiaceae. Ever since Bentham (1857) the status of Loganiaceae has been questioned, and several segregates of that family have been proposed both before and after his treatment. In this study we present cladistic results that show Loganiaceae, sensu lato, to be a paraphyletic group definable only by plesiomorphies, with members showing closest relationships to other families of the order. As the impact of different character-state representations of polymorphic terminals remains largely untested, our morphological and phytochemical data were analysed both with restricted polymorphism coding as well as with the monomorphic "subtaxon" recoding method of Nixon and Davis (1991). Both approaches yield highly compatible results, and we here discuss a new classification of the Gentianales based on (i) monophyletic groups identified by outgroup analysis, and (ii) the maximal portrayal of evidence provided by subtaxon polymorphism recoding. Most prominently, the Loganiaceae sensu lato are divided into four segregate families, two previously named (Loganiaceae sensu stricto and Strychnaceae), and two defined as a result of this study (Gelsemiaceae, L. Struwe & V. A. Albert, stat. nov. and Geniostomaceae, L. Struwe & V. A. Albert, fam. nov.). Apocynaceae (incl. Asclepiadaceae), Gentianaceae (incl. Loganiaceae—Potalieae), and Rubiaceae remain as monophyletic families. Outgroup analysis supports both the monophyly of the Gentianales as well as the exclusion from the order of Buddleja, Desfontainia, Plocosperma, Polypremum , and Retzia (all Loganiaceae sensu Leeuwenberg and Leenhouts). 相似文献
565.
566.
Peter Moldéus Peter J. OBrien Hj?rdis Thor Margareta Berggren Sten Orrenius 《FEBS letters》1983,154(2):411-415
Horseradish peroxidase-catalyzed N-demethylation of aminopyrine and dimethylaniline results in generation of free radical intermediates which can interact with glutathione (GSH) to form a glutathione radical. This can either dimerize to yield glutathione disulfide or react with O2 to form oxygenated products of glutathione. Ethylmorphine is not a substrate in the peroxidase-mediated reaction, and free radical intermediates which react with GSH, are not formed from aminopyrine and dimethylaniline when the horseradish peroxidase/H2O2 system is replaced by liver microsomes and NADPH. Therefore, it appears unlikely that formation of free radical intermediates can be responsible for the depletion of GSH observed during N-demethylation of several drugs in isolated liver cells. 相似文献