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51.
Aquatic environmental impact associated with stream-crossing by a pipeline was monitored at Archibald Creek, B.C. for two years. Water chemistry and benthic macroinvertebrates were used as monitoring tools. Results indicated that impacts arising from stream-crossing were short-term and non-residual.Funded by a contract from Canadian Arctic Gas Study Limited, calgary, to Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary. 相似文献
52.
53.
Janine F. Bridges Peter C. Millard John F. Woodley 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,544(2):448-451
The uptake of free and liposome-entrapped 125I-labelled poly(vinylpyrrolidone) was measured in an intestinal sac preparation from adult rats. An an equal concentration of 125I-labelled poly(vinylpyrrolidone), the rate of uptake of the liposome-entrapped material was four times that of the free macromolecule. 相似文献
54.
Peter
hman 《Acta zoologica》1971,52(2):287-297
The outer segment of long and short photoreceptors in the retina of the river lamprey, Lampetra fluviatilis, were studied by light- and fluorescence microscopy together with some different electron microscopic methods. The outer segments show characteristics of both rods and cones and are suggested to represent intermediate kinds of photoreceptors. 相似文献
55.
Caroline van Haaften-Day Peter Russell Susan Carr Lesley Wright 《In vitro cellular & developmental biology. Plant》1988,24(10):965-971
Summary A cell line derived from a human ovarian carcinosarcoma was established in tissue culture and in nude mice. Two sublines,
LDF and HDF, separated by discontinuous density centrifugation were also established from the parent line JoN. The cloning
efficiency of the JoN line was 21%. Morphologic features of adenocarcinoma cells characteristic of the parent JoN cells were
retained in the sublines and clones; all lines showed the same karyotype and DNA content (pseudodiploid and pseudotetraploid).
Keratin, as demonstrated immunohistochemically, was strongly expressed in the parent line JoN and the xenograft tumor, but
not at all in the LDF sublines and only moderately in the HDF sublines. Vimentin, however, was expressed in neither the parent
line JoN nor the xenograft tumor, but was present in both sublines. Transglutaminase and plasminogen activator activity was
high in the parent line JoN. Neither, sublines nor clones showed the same high enzyme activity as the parent line. It is concluded
that this human tumor line JoN is comprised of epithelial cells, capable of multidirectional differentiation. 相似文献
56.
Peter V Scott 《BMJ (Clinical research ed.)》1982,285(6350):1277-1278
57.
The isolation of mutants of Saccharomyces cerevisiae that divide at approximately half the size of the wild type is described. Three mutants have been isolated in which the small size at bud initiation is due to a mutation in a single nuclear gene. 相似文献
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