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621.
David E Salt Nicole Benhamou Magdalena Leszczyniecka Ilya Raskin Ilan Chet 《International journal of phytoremediation》1999,1(1):67-79
By accumulating Cd from solution, roots of hydroponically grown Indian mustard (Brassica juncea L.), a high biomass crop plant, were able to cause substantial reductions in the concentration of Cd in solution. The removal of Cd from solution was linearly correlated with Cd accumulation by roots. Screening of 300 different rhizobacterial isolates identified several that, when inoculated onto roots of Indian mustard, significantly enhanced the total amount of Cd removed from solution. Further investigations revealed that this enhancement was because of an overall increase in root biomass in the rhizobacterial-treated plants. Rhizobacteria were found to accumulate Cd from solution, and ultrastructural observations suggested that rhizobacteria promote the precipitation of Cd on the root surface. By precipitating Cd at the root surface, rhizobacteria reduce the amount of Cd taken up into roots, thereby protecting the plants, and in particular the roots, from the toxic effects of Cd. This reduced Cd toxicity allows for the increased proliferation of roots observed when plants are inoculated with certain rhizobacteria. 相似文献
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Establishment and initial characterization of the ovine mammary epithelial cell line nish 总被引:4,自引:0,他引:4
Neta Ilan Itamar Barash Elisha Gootwine Moshe Shani 《In vitro cellular & developmental biology. Animal》1998,34(4):326-332
Summary Analysis of the molecular mechanisms involved in the differentiation and formation of the characteristic three-dimensional
structures of the developing mammary gland of the major milk-producing livestock (ducts, end buds, and alveoli) requires in vitro model cell cultures. The few cell lines that have been established from dairy animals do not fully reproduce the entire program
of mammary differentiation. Here we present the initial characterization of a unique mammary epithelial cell line derived
spontaneously from midpregnant sheep (NISH). These cells form in vitro functional structures resembling ducts, lateral buds, and alveoli that secrete β-lactoglobulin (BLG) in an ECM (extracellular
matrix)-dependent manner. Interestingly, the presence of growth hormone dramatically increased BLG secretion from NISH cells
cultured on ECM. It appears that GH is required not only to establish the structural organization but also is continuously
needed to maintain BLG expression. Stable transfection of NISH cells with BLG/Human Serum Albumin (HSA) hybrid gene constructs
revealed that the relative level of expression was comparable to the in vivo secretion of HSA in transgenic mice carrying these gene sequences. No expression could be detected in cells transfected with
hybrid genes carrying either HSA cDNA or the entire HSA gene, and HSA expression was dependent on the presence of intronic
sequences. These results demonstrate that NISH cells may prove a useful tool for studying the differentiation and organogenesis
of mammary epithelial cells under defined culture conditions. Furthermore, transfected NISH cells may be an alternative for
the transgenic mouse model in evaluating the potential of gene constructs to be efficiently expressed in the mammary gland
of transgenic farm animals. 相似文献
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Ilan Paperna 《Systematic parasitology》1994,28(1):15-21
Eimeria gastrosauris n. sp. exhibited endogenous development in the stomach lining and secretory epithelia of Heteronotia binoei from the Mt Isa region, northern Queensland. Morphologically similar coccidians were found in the stomach of Oedura monilis from the Mt Speke region, northern Queensland. Oöcysts were oblong-ellipsoids, with bivalved sporocysts, two distinct residua and endogenous sporulation. Oöcysts of similar shape and size were also found in faeces of Gehyra australis from the Townsville region of northern Queensland. Developmental stages, consisting of meronts, merozoites, microgamonts, macrogamonts and developing oöcysts, were observed in H. binoei and O. monilis, and are described. 相似文献
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