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1.
The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primarily South Asian clade of toads, containing the genera Adenomus, Xanthophryne, and Duttaphrynus. Southeast Asian Pedostibes on the other hand, are nested within a Southeast Asian clade, which is the sister lineage to the Southeast Asian river toad genus Phrynoidis. We demonstrate that Indian and Southeast Asian Pedostibes are not only allopatric and polyphyletic, but also exhibit significant differences in morphology and reproductive mode, indicating that the Southeast Asian species’ are not congeneric with the true Pedostibes of India. As a taxonomic solution, we describe a new genus, Rentapia
gen. nov. to accommodate the Southeast Asian species. 相似文献
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The effect of a 30-day treatment with Madiol was studied on the activity of some enzymes, nucleic acids, protein and glycogen content of the liver of adult female rats and youngs born from mothers treated during pregnancy. Madiol caused a significant increase in SDH and Atp-ase activity, and decreased glycogen and acid phosphatase. 相似文献
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Reconstitution of the Na+K+ pump of Ehrlich ascites tumor and enhancement of efficiency by quercetin 总被引:1,自引:0,他引:1
Plasma membranes from Ehrlich ascites tumor cells were solubilized by octylglucoside in the presence of phospholipids. The Na+K+-ATPase was purified from this extract by adsorption and elution from thio-Seph-arose 4B. The enzyme (specific activity, 7 mumoles of ATP hydrolyzed min-1 mg of protein -1) was reconstituted into liposomes by the octyglucoside dilution procedure. An ATP-dependent Na+ influx with low efficiency was observed. On addition of appropriate amounts of quercetin, the Na+ flux/ATP hydrolysis ratio was increased from 0.4 to 1.4. 相似文献
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