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71.
P L Paine C F Austerberry L J Desjarlais S B Horowitz 《The Journal of cell biology》1983,97(4):1240-1242
Cryomicrodissection makes possible the measurement of the entire in vivo protein content of the amphibian oocyte nucleus and provides a heretofore missing baseline for estimating protein loss during nuclear isolation by other methods. When oocyte nuclei are isolated into an aqueous medium, they lose 95% of their protein with a half-time of 250 s. This result implies an even more rapid loss of protein from aqueously isolated nuclei of ordinary-size cells. 相似文献
72.
In 12 months'' use of a mobile unit for cervical and breast cancer screening in Gloucestershire 3,211 women attended at an average of five sessions a week. Clinic sessions were organized and the running costs of the service met by a voluntary organization. The keeping of records, provision of laboratory facilities, and the follow-up of patients were carried out in close cooperation with the county health department. 相似文献
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74.
Synopsis Fantail darters,Etheostoma flabellare, have larger eggs with greater yolk volume than johnny darters,E. nigrum, and have a longer embryo period. This longer embryo period is associated with accelerated finfold differentiation, producing
a larger, better formed individual at the onset of exogenous feeding. Developmental differences among these two species and
the rainbow darter,Etheostoma caeruleum, primarily in timing of ontogenetic events, are described in detail. These differences in timing are considered largely early
developmental phenomena as they affect embryos, larvae, and aievins but apparently not juveniles or adults. Demographic aspects
of early life history were assessed using data from studies of Ontario streams. Differences in early survival among species
appear to play an important role in recruitment of mature females, but cannot be attributed to parental care or egg size differences. 相似文献
75.
76.
Francis Paine Conant 《Human ecology: an interdisciplinary journal》1994,22(3):405-413
Four predictions are made on the future of space age technologies in human and cultural ecology: first, remote sensing systems will generate a need for more fieldwork, not less; second, the services and skills of anthropologists will become essential to the interpretation of satellite data, especially as these relate to areas characterized by non-Western cultural practices; third, training in remote sensing and the use of geographic information systems will become a regular offering for anthropology students; and fourth, since these new systems and methods can be applied retrospectively to the re-analysis of earlier ethnographic works, space age technologies will be with us for some time to come. 相似文献
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78.
Summary Loblolly pines (Pinus taeda) are rapidly killed by colonizing southern pine beetle (Dendroctonus frontalis). The female beetles carry two species of fungi (Ceratocystis minor var. barrasii and an unnamed basidiomycete) within a mycangium. The insects are also frequently associated with a blue-staining form of C. minor. These fungi are inoculated into the tree during colonization. The tree has an induced defensive response that involves resin soaking and necrosis of affected tissue isolating the invading organlsms. The blue-staining fungus stimulates formation of this response in the tree, but the two mycangial fungi do not. These results suggest that the beetles are closely associated with two highly pathogenic fungi that do not stimulate one of the critical components of tree defense. 相似文献
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80.