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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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Richard B. Pouw Mieke C. Brouwer Judy Geissler Laurens V. van Herpen Sacha S. Zeerleder Walter A. Wuillemin Diana Wouters Taco W. Kuijpers 《PloS one》2016,11(3)
The major human complement regulator in blood, complement factor H (FH), has several closely related proteins, called FH-related (FHR) proteins. As all FHRs lack relevant complement regulatory activity, their physiological role is not well understood. FHR protein 3 (FHR-3) has been suggested to compete with FH for binding to Neisseria meningitidis, thereby affecting complement-mediated clearance. Clearly, the in vivo outcome of such competition greatly depends on the FH and FHR-3 concentrations. While FH levels have been established, accurate FHR-3 levels were never unequivocally reported to date. Moreover, CFHR3 gene copy numbers commonly vary, which may impact the FHR-3 concentration. Hence, we generated five anti-FHR-3 mAbs to specifically measure FHR-3 in human healthy donors of which we determined the gene copy number variation at the CFH/CFHR locus. Finally, we examined the acute-phase response characteristics of FHR-3 in a small sepsis cohort. We determined FHR-3 levels to have a mean of 19 nM and that under normal conditions the copy number of CFHR3 correlates to a very large extent with the FHR-3 serum levels. On average, FHR-3 was 132-fold lower compared to the FH concentration in the same serum samples and FHR-3 did not behave as a major acute phase response protein. 相似文献
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Ilana Blum Nili Schoenfeld Abraham Atsmon 《Biochimica et Biophysica Acta (BBA)/General Subjects》1973,320(2):242-248
Experimental porphyria was induced in rats by allylisopropylacetamide. DL-Propranolol, a β-adrenergic-receptor blocking agent, significantly reduced the elevated urinary excretion of δ-aminolevulinic acid, porphobilinogen and total porphyrins. DL-Propranolol also partially prevented the increased activity of δ-aminolevulinic acid synthesis in liver homogenates of allylisopropylacetamide-treated rats. It had no effect on the above parameters in normal rats. These findings support the hypothesis that δ-aminolevulinic acid exists in two forms, a constitutive and an inducible one.In order to examine whether the action of the drug was caused by its membrane effect. D-propranolol and quinidine sulphate were used in similar sets of experiments. These drugs had no effect on the abnormal porphyrin metabolism of allylisoprpyl-acetamide-treated rats, indicating that the results obtained with DL-propranolol were not due to its membrane action. 相似文献