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A tissue-culture assay for mutagenesis and cytotoxicity incorporating near ultraviolet (NUV) light activation of polyaromatic hydrocarbons (PAH) has been developed. Cultures of Chinese hamster cells (line CHO) growing in suspension culture were inoculated with benzo[a]pyrene (B[a]P), 7,12-dimethylbenzanthracene (DMBA) or shale-oil retort-water and exposed to light from a high-pressure mercury lamp fitted with a Corning NUV bandpass filter. This light source both permitted activation of PAH and the shale-oil water and preculded detectable damage to DNA. Neither the PAH nor the NUV alone had any effect on cell survival or mutation frequencies but the chemicals plus NUV were extremely effective in producing mutations to 6-thioguanine resistance (hgprt gene). 相似文献
996.
The presence of striated subumbrellar musculature in hydromedusae can be related to the development in hydrozoans of a free-swimming life stage. The detailed ultrastructure of the striated subumbrellar musculature of the anthomedusan, Pennaria tiarella is presented. The striated musculature of Pennaria resembles vertebrate striated muscle in filament arrangement (L2 lattice pattern) and M line structure. The striation pattern, out-of-register myofilaments, filament structure as determined by rotational symmetry, Z line structure, types of intercellular junctions, and sarcoplasmic reticulum are more similar to structures found in other invertebrate striated muscle. 相似文献
997.
K. M. Summers K. S. Tam P. B. Bartley J. Drysdale H. Y. Zoghbi J. W. Halliday L. W. Powell 《Human genetics》1991,88(2):175-178
Summary We have used a somatic cell hybrid regional mapping panel for the short arm of chromosome 6, linkage analysis and a population study to map in detail a previously described ferritin heavy chain pseudogene sequence on chromosome 6. Our results show that this sequence maps to the short arm of chromosome 6 centromeric to the glyoxylase locus. The ferritin pseudogene locus is thus distant from the locus for the iron storage disease haemochromatosis, confirming previous evidence that this sequence is not a candidate for the haemochromatosis gene. 相似文献
998.
Ron Summers Nick Christian Brian Etheridge Stuart Rae Ian Cleasby Snæbjörn Pálsson 《Bird Study》2020,67(1):1-7
ABSTRACT Capsule: Scottish-breeding Greenshanks Tringa nebularia migrate largely to Ireland. Aims: To describe the migration timings and determine the non-breeding areas (staging and wintering areas) of Scottish-breeding Greenshanks. Methods: Breeding adult Greenshanks were marked with geolocators and/or unique permutations of colour-rings in Sutherland, northern Scotland. Sightings of the colour-ringed birds and data from geolocators on recaptured birds provided information on the migrations and locations of the non-breeding areas. Results: Scottish-breeding Greenshanks spent the winter mainly in Ireland, with the range also including Wales, southern England and western France. Departure from the breeding grounds, as determined by the geolocators, took place in June and July; the median date for the last day in the breeding area was 16 July. Arrival on the breeding grounds took place in March and April; the median date for the first day back in the breeding area was 7 April. Some birds fed at an estuary close to their territories prior to breeding. There was fidelity to wintering areas, both within and between years. Short-term staging took place during both the southward and northward migrations for some birds, and one bird used the same staging area in different autumns. Members of one pair had separate wintering areas. Conclusions: Scottish-breeding Greenshanks have a short migration, largely to the coasts of Ireland. The migrations involved short-term staging for some birds. 相似文献
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Jung Soh Paul MK Gordon Morgan L Taschuk Anguo Dong Andrew C Ah-Seng Andrei L Turinsky Christoph W Sensen 《BMC bioinformatics》2008,9(1):450