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21.
Between December 2002 and June 2004, 10 marbled salamanders, Ambystoma opacum, were examined for coccidian parasites. Salamanders were collected in Bradley (n = 2), Little River (n = 1), Miller (n = 1), and Sevier (n = 1) Counties, Arkansas; Webster Parish, Louisiana (n = 2); and Bowie (n = 1) and Nacogdoches (n = 2) Counties, Texas. Two of 10 (20%) A. opacum from Louisiana harbored an undescribed species of Eimeria. Oocysts of Eimeria trauthi n. sp. were ellipsoidal, 36.6 x 33.1 (33-40 x 29-37) microm, with a thin, single-layered wall; shape index 1.1. Polar granule(s) and micropyle were absent. Oocyst residuum was composed of hundreds of loosely packed homogenous granules of various sizes enclosing a vacuole. Sporocysts were elongate-ellipsoidal, 20.8 x 8.1 (19-22 x 7-9) microm; shape index 2.6. Sporocyst residuum was spherical and composed of a cluster of granules often membrane-bound. This is the first time a coccidium has been reported from an amphibian species in Louisiana and the second time a coccidium has been described from this salamander host. In addition, the following 26 salamanders from various counties in Arkansas, Oklahoma, and Texas were surveyed during the study period and were negative for coccidia: Ambystomatidae, 4 spotted salamanders (Ambystoma maculatum) and 7 mole salamanders (Ambystoma talpoideum); Cryptobranchidae, 4 Ozark hellbenders (Cryptobranchus alleganiensis bishopi); Plethodontidae, 6 spotted dusky salamanders (Desmognathus conanti) and 3 many-ribbed salamanders (Eurycea multiplicata multiplicata); and Salamandridae, 2 central newts (Notophthalmus viridescens louisianensis). 相似文献
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A technique was developed to examine the effects of exogenous substances on apicomplexan sporozoite motility in vitro. Sporozoites of Eimeria nieschulzi were placed in the top compartments of blind well chemotactic chambers and separated from potential chemoattractant/chemokinetic agents by 8.0-microns pore size Millipore filters. After 3-hr incubations, the number of sporozoites migrating through the filters was assessed using a hemacytometer. Results revealed that several substances, especially albumin and fetuin, enhanced motility of coccidial sporozoites. Cell culture assays supported these data, with higher numbers of parasites found in cultures supplemented with albumin and/or fetuin. 相似文献
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Rebecca L. Upton 《American anthropologist》2000,102(2):395-396
Population, Gender and Politics: Demographic Change in Rural North India. Roger Jeffery and Patricia Jeffery. New York: Cambridge University Press, 1997. 278 pp. 相似文献
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Pituitary peptides. Resolution by gel filtration 总被引:2,自引:0,他引:2
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He Jiang Richard M. Salmon Paul D. Upton Zhenquan Wei Aleksandra Lawera Anthony P. Davenport Nicholas W. Morrell Wei Li 《The Journal of biological chemistry》2016,291(6):2954-2966
BMP10 is highly expressed in the developing heart and plays essential roles in cardiogenesis. BMP10 deletion in mice results in embryonic lethality because of impaired cardiac development. In adults, BMP10 expression is restricted to the right atrium, though ventricular hypertrophy is accompanied by increased BMP10 expression in a rat hypertension model. However, reports of BMP10 activity in the circulation are inconclusive. In particular, it is not known whether in vivo secreted BMP10 is active or whether additional factors are required to achieve its bioactivity. It has been shown that high-affinity binding of the BMP10 prodomain to the mature ligand inhibits BMP10 signaling activity in C2C12 cells, and it was proposed that prodomain-bound BMP10 (pBMP10) complex is latent. In this study, we demonstrated that the BMP10 prodomain did not inhibit BMP10 signaling activity in multiple endothelial cells, and that recombinant human pBMP10 complex, expressed in mammalian cells and purified under native conditions, was fully active. In addition, both BMP10 in human plasma and BMP10 secreted from the mouse right atrium were fully active. Finally, we confirmed that active BMP10 secreted from mouse right atrium was in the prodomain-bound form. Our data suggest that circulating BMP10 in adults is fully active and that the reported vascular quiescence function of BMP10 in vivo is due to the direct activity of pBMP10 and does not require an additional activation step. Moreover, being an active ligand, recombinant pBMP10 may have therapeutic potential as an endothelial-selective BMP ligand, in conditions characterized by loss of BMP9/10 signaling. 相似文献
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