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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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Vinod Kumar 《Chronobiology international》1986,3(3):165-170
Groups of photosensitive, unstimulated or stimulated, male blackheaded buntings were subjected to photoregimes of 15 hr of green light of three intensities and 9 hr of dark per day. In some groups green light was interrupted with 90 min of bright fluorescent light at different times in the subjective day. While gonads did not develop or regressed in some groups, birds in others behaved as if exposed to long daylengths. The results besides suggesting the involvement of endogenous circadian rhythm during initiation and maintenance of gonadal growth indicate that the reproductive rhythms are entrained and induced by environmental photoperiod. 相似文献
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The production of d-aminoacylase by Alcaligenes denitrificans and Alcaligenes faecalis has been studied. The enzyme was inducibly produced and N-acetyl-d-leucine and N-acetyl-d-valine were the most effective inducers. d-methionine, d-valine, d-phenylalamine and d-leucine were produced by the enzymic hydrolysis of the appropriate N-acetyl-d-amino-acids with whole cell biomass. The hydrolysis of N-acetyl-d-methionine by A. denitrificans and N-acetyl-d-valine by A. faecalis was preferential. Maximum yields of d-methionine and d-valine were 94.3 and 84.7% at a specific product formation rate of 20.10 and 19.19 μmol min−1 mg−1 of wet cells at 20 mM substrate concentration and 5 mg ml−1 of cell density. 相似文献
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