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991.
D. E. Dussourd C. A. Harvis J. Meinwald T. Eisner 《Cellular and molecular life sciences : CMLS》1989,45(9):896-898
Summary Pyrrolizidine alkaloid sequestered by adult maleDanaus gilippus from plants is transferred in large measure to the female at mating, and by the female to the eggs. The eggs, presumably, are protected as a result. The male's courtship pheromone, danaidone, derived from the sequestered alkaloid, may function to advertise the male's alkaloid-donating capacity.Acknowledgments. Paper Nr. 89 of the series Defense Mechanisms of Arthropods. Study supported by NIH (Grants AI-02908 and AI-12020; Predoctoral Traineeship to DED), Hatch funds (191-7416), the Bache Fund (National Academy of Sciences, to DED), and the Theodore Roosevelt Memorial Fund (American Museum of Natural History, to DED). We thank M. Weingarner and J. Miller forD. gilippus collection, J. Boggan for technical assistance, and the staff of the Archbold Biological Station, Lake Placid, Florida, for assistance and hospitality. One of us (DED) is indebted to M. D. Achey, who by demonstrating nuptial cardenolide transfer in the monarch butterfly [Honors Thesis, Amherst College, Amherst, Massachusetts (1979)] raised the possibility that other plant metabolites might be similarly transferred in danaines.Deceased July, 1985. This paper is affectionately dedicated to his memory. 相似文献
992.
Heterosexual chemoattraction studies on juvenile worms showed that 20- and 21-day-old worms do not attract each other, whereas 23- and 28-day-old worms are attracted to each other and pair with worms of the opposite sex. This onset of chemoattraction in vitro corresponds to the time when worms begin pairing in vivo. The ability of single worms to locate each other and mate is presumably mediated by chemoreceptors. 相似文献
993.
R. G. Knodell P. P. Toskes H. A. Reber F. P. Brooks 《Cellular and molecular life sciences : CMLS》1970,26(5):515-517
Zusammenfassung Nachweis, dass die Zufuhr von dibutyryl-zyklischem AMP (DcAMP) in vitro die Enzymproduktion erhöht und zwar mit nur geringer Gewichtsveränderung des Kaninchenpankreas. Die Enzymproduktion wird ebenso durch Theophyllin vermehrt und es wird vermutet, das DcAMP der Vermittler der pankreozymen Wirkung im Kaninchen ist. 相似文献
994.
A. M. Firenzuoli E. Mastronuzzi P. Vanni A. Zanobini 《Cellular and molecular life sciences : CMLS》1970,26(6):596-598
Riassunto Durante la germinazione diPinus pinea i livelli di fosfato libero sono risultati essere correlati a quelli della fosfatasi acida, anche in differenti parti della plantula. I valori di fosfato totale sono costanti in tale periodo.
This research was supported by a grant from the Impresa Enzimologica of the Italian Consiglio Nazionale delle Ricerche and from Ministero della Pubblica Istruzione. 相似文献
This research was supported by a grant from the Impresa Enzimologica of the Italian Consiglio Nazionale delle Ricerche and from Ministero della Pubblica Istruzione. 相似文献
995.
996.
S. K. Dutta S. R. Penn A. R. Knight M. Ojha 《Cellular and molecular life sciences : CMLS》1972,28(5):582-584
Resumé Les rapports G+C des ADN deCoprinus lagopus etMucor azygospora ont été étudiés. Le profil de fusion indique que l'ADN duC. lagopus est composé de deux fractions, une principale (90%) de rapport G+C 52 moles pourcent, une mineure (10%) de G+C 32 moles pourcent. Par contre l'ADN deM. azygospora contient une fraction unique de G+C 38 moles pourcent. L'étude de la cinétique de réassociation DNA:DNA montre que la dimension génomique («genome size») deC. lagopus est de 2×1012 et qu'il y a moin de 10% de DNA à séquences répétées de nucléotides.
This research was supported in part by the U.S. Atomic Energy Commission Contract No. AT (40-1) 4182 and the Research Corporation, New York, to S.K.D. We are grateful to ProfessorG. Turian, University of Geneva, for making possibleM. Ojha's participation in this research. 相似文献
This research was supported in part by the U.S. Atomic Energy Commission Contract No. AT (40-1) 4182 and the Research Corporation, New York, to S.K.D. We are grateful to ProfessorG. Turian, University of Geneva, for making possibleM. Ojha's participation in this research. 相似文献
997.
A. Meylan 《Cellular and molecular life sciences : CMLS》1972,28(12):1508-1511
Summary The Robertsonian polymorphism ofPitymys subterraneus involves only 1 pair of metacentric autosomes. The crosses of forms with 52, 53 and 54 chromosomes do not show any differences in their reproductive rate. So a single autosome trivalent does not affect the fecondity. Many hybrids have been obtained betweenP. subterraneus (2N=52 or 54) andP. multiplex (2N=48) with 50 or 51 chromosomes, respectively. Even with a heterogenous karyotype they are not entirely sterile. 2 progeny were produced from back-crosses. The 2 parental species seem to result from recent speciation. Only fecondation or embryogenesis occurs in crossingP. duodecimcostatus withP. subterraneus orP. multiplex. The chromosome complement of 1 hybrid embryo ofP. duodecimcostatus (2N=62)×P. multiplex (2N=48) has been studied showing 55 chromosomes.P. duodecimcostatus appears to belong to a more distant evolutionary group. 相似文献
998.
Résumé On a donné de la nicotine à des rats une fois par jour, pendant 10 jours. L'activité des animaux a d'abord diminué, mais après quelques administrations de la drogue, on constata une accoutumance à ces effets. L'administration terminée, l'activité a augmenté.
This work was supported by a grant from the Tobacco Research Council. 相似文献
This work was supported by a grant from the Tobacco Research Council. 相似文献
999.
R. Marcos J. López de Sepúlveda N. Xamena A. Creus 《Cellular and molecular life sciences : CMLS》1981,37(6):559-560
Summary Ethidium bromide was fed toD. melanogaster andD. simulans males in order to test its toxic capacity and potency for the induction of dominant lethals. Our results show that ethidium bromide has a high toxicity and likewise produces dominant lethals to a significant extent in both species, but more effectively inD. melanogaster. 相似文献
1000.
Summary The phenetic relationships between the families of the Hamamelididae subclass were studied by using the following multifactorial analytical methods: principal components analysis (PCA) and reciprocal averaging (RA). The results obtained agree appreciably with Takhtajan's classification system.
Remerciements. Nous remercions Mlle Sylvie Laliberté, Institut botanique de l'Université de Montréal, pour sa révision du manuscrit; M. Michel Labrecque, Institut botanique de l'Université de Montréal, pour avoir dessiné les figures; de même que M. André Bouchard, Jardin Botanique de Montréal et Institut botanique de l'Université de Montréal, de nous avoir permis d'utiliser les programmes dont il se sert pour ses travaux d'écologie. 相似文献
Remerciements. Nous remercions Mlle Sylvie Laliberté, Institut botanique de l'Université de Montréal, pour sa révision du manuscrit; M. Michel Labrecque, Institut botanique de l'Université de Montréal, pour avoir dessiné les figures; de même que M. André Bouchard, Jardin Botanique de Montréal et Institut botanique de l'Université de Montréal, de nous avoir permis d'utiliser les programmes dont il se sert pour ses travaux d'écologie. 相似文献