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J. A. Rideout Narelle B. Smith M. D. Sutherland 《Cellular and molecular life sciences : CMLS》1979,35(10):1273-1274
Summary The range of (presumed) polyketide constituents in comatalid crinoids has been extended to include bianthronyls, meso-naphthodianthrones and sulphate esters of various of the polyketides. Several species of fish are deterred from eating food by the inclusion in it of these sulphates at the concentration found in crinoids. Sodium 2-hydroxy-anthraquinone sulphate and anthraquinone-2-suphonate were also active as antifeedants for the species tested.Acknowledgments. This author is indebted to the Australian Research Grants Commission for financial support, to Miss A. Clark of the British Museum of Natural History, London, and Ms J. Marshall of the Australian Museum, Sydney, for identifications of crinoid specimens and to Mr C. Lee, Director of the Deception Bay Laboratory of the Qld. Fisheries Service for providing facilities, fish and valuable advice. 相似文献
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D. L. Fox V. Elliott Smith A. A. Wolfson 《Cellular and molecular life sciences : CMLS》1967,23(11):965-966
Zusammenfassung Die blauen ozeanischen Cirripedien,Lepas fascicularis, speichern Karotinoide in Eiern, Eingeweiden und den meisten übrigen Geweben in den folgenden ungefähren Konzentrationen: 5:2:1 mg/100 g. In jeder Art von Gewebe ist Astaxanthin das Hauptkarotinoid, welches meist in Form des blauen Chromproteins vorliegt. Kleinere Mengen von Karotin und etwas mehr Xanthophylle kommen in den Eingeweiden, nicht aber in den reifen Eiern vor.
Contribution from the Scripps Institution of Oceanography. This research was supported by Research Grant No. GB-5332X from the National Science Foundation. We are indebted also toJoanne Rhoads andP. Wiebe for donating some of the fresh barnacle specimens, and to Dr.W. A. Newman for his help and information concerning the biology and dissection of this barnacle. 相似文献
Contribution from the Scripps Institution of Oceanography. This research was supported by Research Grant No. GB-5332X from the National Science Foundation. We are indebted also toJoanne Rhoads andP. Wiebe for donating some of the fresh barnacle specimens, and to Dr.W. A. Newman for his help and information concerning the biology and dissection of this barnacle. 相似文献
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I. Torres N. W. Th. Smith Ch. Oxnard 《Cellular and molecular life sciences : CMLS》1969,25(3):273-275
Resumen Monos cautivos mantenidos en una dieta vegetariana presentaron niveles séricos de vitamina B12 reducidos y lesiones en el sistema nervioso central semejantes a las de la «degeneración combinada sub aguda» del humano. Los nervios periféricos mostraron desmielinización segmentaria, compatible con un compromiso de las células de Schwann al azar. Usualmente hubo remielinización segmentaria, asociada a veces con degeneración axónica (walleriana). No se encontró evidencia de remielinización o de regeneración axónica que pudiera ser atribuída totalmente al tratamiento con vitamina B12. 相似文献
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Mitotic EBNA-positive lymphocytes in peripheral blood during infectious mononucleosis 总被引:7,自引:0,他引:7
Infectious mononucleosis (IM) is usually a benign lymphoproliferative disease caused by Epstein-Barr virus (EBV). Although EBV induces a state of continuous proliferation in infected B lymphocytes in vitro, the most prominent lymphoproliferation during IM is of activated, or atypical, T lymphocytes presumably responding to the virus or virus-infected cells. However, EBV genome-carrying cells are known to be circulating during IM, as cultured peripheral blood leukocytes from patients with the disease give rise to continuous lymphoblastoid cell lines, each cell of which contains the EBV genome and expresses the EBV determined nuclear antigen (EBNA). The proposal that EBV-infected cells in IM blood are not endowed with enhanced growth potential but are merely latently infected is supported by demonstrations that cells infected in vivo enter a viral replicative cycle when placed in vitro and that most cell lines derived from cultured lymphocytes of IM patients are infected by virus released in vitro. However the cells could also be capable of proliferation in vivo, since virus production and transformation are not mutually exclusive properties of EBV-transformed cells. Recently, EBNA has been detected in a very small fraction of peripheral blood lymphocytes of IM patients after T cells were first removed and this has been interpreted to indicate that cell transformation occurs in vivo during IM. The isolation of colonies of EBNA-positive cells from IM blood leukocytes cultures in soft agar suggests that at least some infected cells are capable of direct outgrowth into transformed cells. We report here direct evidence that circulating EBV-infected cells exhibit increased growth properties during IM. 相似文献