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排序方式: 共有470条查询结果,搜索用时 15 毫秒
31.
Allan D. McDevitt Naiara Guimarães Sales Samuel S. Browett Abbie O. Sparnenn Stefano Mariani Owen S. Wangensteen Ilaria Coscia Chiara Benvenuto 《Journal of fish biology》2019,95(2):679-682
We focus on a case study along an English canal comparing environmental DNA (eDNA) metabarcoding with two types of electrofishing techniques (wade-and-reach and boom-boat). In addition to corroborating data obtained by electrofishing, eDNA provided a wider snapshot of fish assemblages. Given the semi-lotic nature of canals, we encourage the use of eDNA as a fast and cost-effective tool to detect and monitor whole fish communities. 相似文献
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DUJARRIC DE LA RIVIERE R 《Biologie médicale》1954,43(3):233-250
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Polarization is a common feature of many types of cells, and we are beginning to understand how cells become polarized. The role of cell polarity in development and tissue morphogenesis, however, is much less well understood. Our previous analysis of the mosaic eyes (moe) mutations revealed that moe is required for retinal lamination and also suggested that zebrafish moe function is required in the retinal pigmented epithelium (RPE) for the proper localization of adjacent retinal cell divisions at the apical neuroepithelial surface. To understand the function of moe in the RPE, we cloned the moe locus and show that it encodes a novel FERM (for 4.1 protein, ezrin, radixin, moesin) domain-containing protein. Expression of moe in the eye, kidney, and brain reflects phenotypes found in moe(-) mutants, including RPE and retinal lamination defects, edema, and small or absent brain ventricles. We show that moe function is required for tight junction formation in the RPE. We suggest that moe may be a necessary component of the crumbs pathway that regulates apical cell polarity and also may play a role in photoreceptor morphogenesis. 相似文献
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Clader JW Billard W Binch H Chen LY Crosby G Duffy RA Ford J Kozlowski JA Lachowicz JE Li S Liu C McCombie SW Vice S Zhou G Greenlee WJ 《Bioorganic & medicinal chemistry》2004,12(2):319-326
Anthranilamide analogues such as 23 are potent and highly selective muscarinic M2 antagonists that also show good oral bioavailability and in vivo activity. 相似文献
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Morgan-Ryan UM Fall A Ward LA Hijjawi N Sulaiman I Fayer R Thompson RC Olson M Lal A Xiao L 《The Journal of eukaryotic microbiology》2002,49(6):433-440
The structure and infectivity of the oocysts of a new species of Cryptosporidium from the feces of humans are described. Oocysts are structurally indistinguishable from those of Cryptosporidium parvum. Oocysts of the new species are passed fully sporulated, lack sporocysts. and measure 4.4-5.4 microm (mean = 4.86) x 4.4-5.9 microm (mean = 5.2 microm) with a length to width ratio 1.0-1.09 (mean 1.07) (n = 100). Oocysts were not infectious for ARC Swiss mice, nude mice. Wistar rat pups, puppies, kittens or calves, but were infectious to neonatal gnotobiotic pigs. Pathogenicity studies in the gnotobiotic pig model revealed significant differences in parasite-associated lesion distribution (P = 0.005 to P = 0.02) and intensity of infection (P = 0.04) between C. parvum and this newly described species from humans. In vitro cultivation studies have also revealed growth differences between the two species. Multi-locus analysis of numerous unlinked loci, including a preliminary sequence scan of the entire genome demonstrated this species to be distinct from C. parvum and also demonstrated a lack of recombination, providing further support for its species status. Based on biological and molecular data, this Cryptosporidium infecting the intestine of humans is proposed to be a new species Cryptosporidium hominis n. sp. 相似文献
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E?DimitriadisEmail author L?Robb Y-X?Liu AC?Enders H?Martin C?Stoikos E?Wallace LA?Salamonsen 《Reproductive biology and endocrinology : RB&E》2003,1(1):34
Embryo implantation, endometrial stromal cell decidualization and formation of a functional placenta are critical processes in the establishment and maintenance of pregnancy. Interleukin (IL)-11 signalling is essential for adequate decidualization in the mouse uterus and IL-11 promotes decidualization in the human. IL-11 action is mediated via binding to the specific IL-11 receptor α (IL-11Rα). The present study examined immunoreactive IL-11 and IL-11Rα in cycling rhesus monkey endometrium, at implantation sites in cynomolgus and rhesus monkeys and in human first trimester decidua and defined distinct spatial and temporal patterns. In cycling rhesus monkey endometrium, IL-11 and IL-11Rα increased in both basalis and functionalis regions during the secretory compared with the proliferative phase, with changing cellular locations in luminal and glandular epithelium and stroma. The patterns were similar overall to those previously described in human endometrium. Differences were seen in immunostaining during implantation in cynomologus and rhesus monkey. In the cynomolgus, very little staining for IL-11 or IL-11Rα was seen in syncytio- and cyto-trophoblast cells in the villi between days 12 and 150 of pregnancy although there was moderate staining in cytotrophoblast in the shell between days 12 and 17 and in subpopulations of cytotrophoblast cells invading the arteries at day 17. By contrast in the rhesus monkey between days 24 and 35 of pregnancy and in human first trimester placenta, cyto- and syncytio-trophoblast in the villi but not cytotrophoblast in the shell were positively stained. The most intense staining for both IL-11 and IL-11Rα was present within the decidua in the maternal component of implantation sites in all three primates but moderate staining was also present in maternal vascular smooth muscle and glands perivascular cells and epithelial plaques. These results are consistent with a role for IL-11 both during decidualization and placentation in primates. 相似文献