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91.
Didier Fraix-Burnet Philippe Choler Emmanuel J.P. Douzery Anne Verhamme 《Journal of Classification》2006,23(1):57-78
This series of papers is intended to evaluate astrocladistics in reconstructing phylogenies of galaxies. The objective of
this second paper is to formalize the concept of galaxy formation and to identify the processes of diversification. We show
that galaxy diversity can be expected to organize itself in a hierarchy. In order to better understand the role of mergers,
we have selected a sample of 43 galaxies from the GALICS database built from simulations with a hybrid model for galaxy formation
studies. These simulated galaxies, described by 119 characters and considered as representing still undefined classes, have
experienced different numbers of merger events during evolution. Our cladistic analysis yields a robust tree that proves the
existence of a hierarchy. Mergers, like interactions (not taken into account in the GALICS simulations), are probably a strong
driver for galaxy diversification. Our result shows that mergers participate in a branching type of evolution, but do not
seem to play the role of an evolutionary clock. 相似文献
92.
R Emanoil-Ravicovitch J Robert M Canivet L D'Auriol J Périès 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(17):1277-1280
Murine type C viral information is detectable in the cellular genome of both differentiated and undifferentiated cell lines derived from 129 Mouse teratocarcinoma. Cytoplasmic RNA expression which is negligible in differentiated cells, is significantly higher in multipotential undifferentiated cells. Furthermore it was observed that in vitro differentiation of multipotent cells leads to a decrease of this expression. 相似文献
93.
C. P. Vivarès J. Trellu H. J. Ceccaldi 《Cellular and molecular life sciences : CMLS》1977,33(10):1311-1312
Summary The use of the method of concentration gradient of polyacrylamide gel, electrophoresis has permitted to reveal a difference in zymograms when studying the hemolymph of healthy crabs and that of crabs parasitized by the muscular microsporidaThelohania, maenadis., The zymograms of the parasitized crabs present an increase in chymotrypsin activity and variations in the zones of esterase activity.
Contribution no 1 du Centre de Parasitologie et de Pathologie comparées de l'Université des Sciences et Techniques du Languedoc, F-34060 Montpellier Cédex. 相似文献
Contribution no 1 du Centre de Parasitologie et de Pathologie comparées de l'Université des Sciences et Techniques du Languedoc, F-34060 Montpellier Cédex. 相似文献
94.
Gisèle Cherqui Monique Cadot C. Senault R. Portet 《Cellular and molecular life sciences : CMLS》1979,35(10):1353-1354
Summary Cold acclimatization induces morphological and compositional modifications of rat epididymal adipose tissue: a decrease in fat cell size, an increase of fat cell number per g of tissue, but no significant increase in total fat cell number in the tissue; finally, an increase in protein content and a decrease in triglyceride content.Acknowledgments. We especially thank Mr M. Joliff for his very valuable help for fat cell size determination (Hospital Bichat, Paris). 相似文献
95.
Rat x rat hybrid myelomas and a monoclonal anti-Fd portion of mouse IgG. 总被引:33,自引:0,他引:33
96.
97.
98.
Anne R. Dain 《Cellular and molecular life sciences : CMLS》1980,36(12):1358-1360
Summary An account is given of stillborn male twins born to a female Saanen goat (Capra hircus) and a Barbary ram (Ammotragus lervia). The cytogenetics of the cultured hybrid cells are described and attention is drawn to the high proportion of cells which lacked one chromosome.Acknowledgment. I. gratefully acknowledge the help of Mr G.E. Embleton who took the skin biopsy of the Barbary ram. 相似文献
99.
What's new in chitinase research? 总被引:9,自引:0,他引:9
This review article deals with recent developments in molecular and physiological aspects of chitinases from plants, fungi, bacteria, insects and fishes. 相似文献
100.
E. F. Gilbert R. J. Hodach M. O. Cheung H. J. Bruyère Jr 《Cellular and molecular life sciences : CMLS》1976,32(8):1026-1027
Summary Cocaine potentiates the effects of epinephrine and norepinephrine in terms of aortic arch malformation in embryonic chicks. Cocaine itself induces aortic arch malformations when administered in large doses.This study was supported by grant No. HL 18050, National Heart and Lung Institute, National Institutes of Health, Bethesda, Maryland. 相似文献