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N Thiernesse A David J Bernard P Jeannesson D Zagury 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(6):713-715
The localization of Golgi areas, particularly lysosomal bodies detected by their acid phosphatase activities, has been determined in the cytotoxic lymphocytes conjugated to their target cell. The study points out the preferential situation of these organelles close to the contact area between the two cells during the target cell lysis. 相似文献
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P Lemay N Pluquet de Temmerman A Tavitian J Bernard 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(24):2573-2575
A DNA complementary to the viral genome of C-type particles produced by a Mouse myeloma derived cell line (MF2 cell line) was synthesized. This cDNA was used as a probe to study the viral genome expression among the total RNA and the poly (A)-rich RNA extracted from the MF2 and Balb/c embryonic cells. As evidenced by molecular hybridization experiments, the presence of at least one endogenous Balb/c virus in the MF2 virus stocks is suggested. In the productive cells, the viral RNA sequences are expressed in the poly (A)-rich RNA fraction. 相似文献
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C Batini J F Bernard C Buisseret-Delmas G Horcholle-Bossavit 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(11):905-907
The effects of tremogenic doses of harmaline have been studied by extracellular unit recordings and 14C 2-deoxyglucose marking in two groups of cats. Harmaline sensitive neurons were found in the lateral reticular nucleus and the nucleus reticularis tegmenti pontis. The nucleus interpositus as well as the red nucleus were also found to be discharging at the tremor frequency, indicating that the cerebello-interposito-rubral system participates in harmaline tremor. In cats with unilateral sections of the inferior cerebellar peduncle, 14C 2-deoxyglucose marking demonstrated that the increased activity previously observed in those structures was a consequence of harmaline acting on the inferior olive. 相似文献
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Lead levels in the nervous system of rats intoxicated for 8 months by lead acetate (0.2% in drinking water) varied according to the region: the lowest levels were observed in sciatic nerve and the highest in hippocampus and cerebral neocortex, while intermediate levels were observed in pons medulla, cerebellum, midbrain, hypothalamus and striatum. 相似文献
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On the use of ordered sets in problems of comparison and consensus of classifications 总被引:7,自引:7,他引:0
Ordered set theory provides efficient tools for the problems of comparison and consensus of classifications Here, an overview of results obtained by the ordinal approach is presented Latticial or semilatticial structures of the main sets of classification models are described Many results on partitions are adaptable to dendrograms; many results on n-trees hold in any median semilattice and thus have counterparts on ordered trees and Buneman (phylogenetic) trees For the comparison of classifications, the semimodularity of the ordinal structures involved yields computable least-move metrics based on weighted or unweighted elementary transformations In the unweighted case, these metrics have simple characteristic properties For the consensus of classifications, the constructive, axiomatic, and optimization approaches are considered Natural consensus rules (majoritary, oligarchic, ) have adequate ordinal formalizations A unified presentation of Arrow-like characterization results is given In the cases of n-trees, ordered trees and Buneman trees, the majority rule is a significant example where the three approaches convergeThe authors would like to thank the anonymous referees for helpful suggestions on the first draft of this paper, and W H E Day for his comments and his significant improvements of style 相似文献