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1.
Summary The title compound, a metabolite of 4,5,6,7-tetrahydrobenzo[b]thien-4-ylurea, was synthesized and found to be an effective growth promoter in sheep, mice, and rats. In sheep it gave over a 6-week growth period at 15 and 60 ppm in the diet an economically and statistically significant growth response.United States adopted name (USAN).We thank Dr T.J. Bentley, D.J. France, and Dr L.D. Spicer for synthesis and structural elucidation work, Dr M.W. Bullock and G.W. Cox for metabolism studies, Drs J. Harter, D. Ingle, J.M. Pensack and L. Wozniak and their associates for biological data, and Drs D.J. Thoennes and M.L. Thomson for spectral data and interpretations.  相似文献   

2.
Summary Ecdysteroid titers were measured in whole-body extracts of pedogenetically reproducing larvae of the dipteran insectHeteropeza pygmaea and in the dietary fungus. The titers are very low in the first 3 days of larval growth, but increase during the last 2 days. The level of 20-hydroxyecdysone is then significantly higher than that of ecdysone. Measurements of the titers in the fungus gave no conclusive results.Supported by the Swiss National Science Foundation, grants No. 3.218-0.77 to D.F.W. and 3.714-0.80 to B.L. We thank Xiang-Xiong Zhu for help with the RIA and Mrs G. Rhyner for technical assistance. Gifts of ecdysone antiserum from Dr J. D. O'Connor and of 23,24-[3H2]-ecdysone from Dr J. Koolman are also gratefully acknowledged.  相似文献   

3.
Summary The attraction ofS. scolytus to the components of Multilure is described. 4-Methyl-3-heptanol is an attractant which is synergised bya-cubebene. Multistriatin appears to be an inhibitor. A combination of 4-methyl-3-heptanol and cubeb oil is more effective as a bait forS. scolytus than Multilure.We thank Mr A. K. Hughes and Mr J. Boswell for their cooperation in allowing us to conduct experiments on Parham Estate; Mr D. Mobbs and Mr C. Thorne for the statistical analyses; Dr J. W. Peacock for samples of mixed isomers of multistriatin and distilled cubeb oil; Mrs J. Allsop and Mr N. J. Fielding for technical assistance. We are grateful to Mr D. Bevan, Dr J. H. Borden, Dr J. F. Grove and Prof. A. W. Johnson for their interest and encouragement.  相似文献   

4.
Summary In rats, both Cu(I) and Cu(II) show an irritancy profile not shared with Cuo or Zn(II) or Ni(II). The gastric response to Cu(II), i.e. copius fluid and mucus secretion, can protect the stomach from the acute ulcerative effects of aspirin or physical stress administered subsequently.to whom all enquiries should be addressed, Supported by grants from the National Health and Medical Research Council (Austr.) and University of Tasmania Research Commitee.Acknowledgments: ProfessorsW. R. Walker (Newcastle, Austr.) andL. Field (Nashville, Tenn.) for gifts of Cu(I) and Zn complexes;Dr. J. R. J. Sorenson (Cincinnatti, Ohio) for illuminating discussion; Drs.D. D. Perrin (Canberra) andR. P. Agarwal (Washington D. C.) for providing stability constants and much helpful advice.  相似文献   

5.
Summary The SCE frequency induced by Thiotepa and the effect of this antineoplastic drug in combination with caffeine have been studied in cultures of human peripheral blood. Caffeine was found to enhance SCE and breakage frequencies induced by Thiotepa in human lymphocytes.Acknowledgment. I am deeply grateful to Dr M.J.W. Faed, for stimulating discussions, guidance and constructive criticism. This paper is a part of my Ph.D. thesis submitted to Dundee University.  相似文献   

6.
Summary Bovine pituitary intraglandular colloid thought to be a waste product, is the holocrine secretion of intermediate lobe cells. It is housed in the intraglandular lumen (residual lumen) and is extruded into the venous circulation of the cavernous sinuses via clefts in the capsule of the gland aligned with the intraglandular lumen. Intraglandular colloid, fraction F5 (mol.wt 34,000), radiolabeled with (125I)Na and injected (0.15 ml) into the right internal jugular vein of male Wistar rats, accumulated in the endocrine pancreas. Autoradiographs showed that the material had specifically localized in the capillary network of the endocrine pancreas. Since the intermediate lobe is poorly vascularized, intraglandular colloid is considered to be the transport medium for intermediate lobe materials.This study was supported by a grant from the Natural Sciences and Engineering Research Council of Canada.I would like to thank S. Choles and J. Bennett for their technical expertise with the help of P. Galvin and W. Halina. I thank members of the Central Animal Facilities, McMaster University Medical Centre, Hamilton, Ontario, for labeling the intraglandular colloid and for counting the decay rate of the tissue. I would also like to thank Drs. A. deBold and J. Kraicer, Faculty of Medicine, Queen's University, Kingston, Ontario, for their interest in this study.  相似文献   

7.
Zusammenfassung Postsynaptische Potentiale der Muskelfasern (EPP) des isolierten Rattenzwerchfells wurden intrazellulär abgeleitet. Die statistische Analyse zeigt, dass der Mengenanteil von EPP bei Anwesenheit von Atropin vermindert ist und zwar simultan mit der postsynaptischen Blockade. Die Erholung des presynaptischen Effektes ist viel langsamer als diejenige des postsynaptischen.

This work was supported by a grant (to J.I.H.) from the US. National Science Foundation. D.F.W. was a postdoctoral fellow of the US Public Health Service.  相似文献   

8.
Summary Two novel prenylat flavones, termed Cannflavin A and B, were isolated from the cannabinoid free ethanolic extract ofCannabis sativa L. Both compounds inhibited prostaglandin E2 production by human rheumatoid synovial cells in culture.This communication is dedicated to the memory of the late Professor J. W. Fairbairn and the late Dr. J. T. Pickens. We are grateful to the Medical Research Council for a project grant and to Ms J. Elliot of King's College London for NMR spectra.  相似文献   

9.
Summary A microelectrode amplifier for intracellular electrophysiological research is described. It is equipped with an electronic infinite resistance constant current source for the injection of current into biological cells. With this amplifier the potential changes, the resistance changes and the dependence on extrinsic current of single cells can be measured independently and simultaneously.Acknowledgments. I am grateful to Dr D.G. Stavenga who inspired me to start the design. I thank P. Cuperus for stimulating discussions and A.J.Th. Liebrand for the construction of the amplifier. This work was supported financially by the Netherlands Organisation for the Advancement of Pure Research (Z.W.O.).  相似文献   

10.
Summary Polyhedral inclusion bodies (P.I.B.) of a nuclear polyhedrosis virus ofHeliothis punctigera (Lep.) were found in excreta ofNabis tasmanicus (Het.), a predator ofH. punctigera. An immunofluorescent counting method was used to estimate numbers of P.I.B. Bioassays demonstrated that no loss of infectivity occurred during passage through the gut.Acknowledgment. I am grateful for the comments and criticism offered by Dr D.E. Pinnock, I thank D.J. Cooper for preparation of materials for the immunofluorescent counting method and J. Hardy for supplying me with eggs ofH. punctigera; all of Department of Entomology, Waite Agricultural Research Institute, Glen Osmond, South Australia.  相似文献   

11.
Summary Cornea regeneration in a Pacific giant octopus,Octopus dofleini, occurred within 10 days after the injury was observed. Surgical removal of the cornea in 2 common octopi,O. vulgaris experimentally duplicated this cornea regeneration within a 10-day period. It is, therefore, concluded that besides sucking discs, arms, and nerve fibres, octopi can also regenerated corneal tissue.The authors would like to thank U. E. Friese, B. Borowski, P. Burn, J.W. Atz, G.J. Nelson, H. Feinberg, P. Fenimore, C. Roper, M. Nixon, M. Segalla, G. Clark, D.O. Calligaro, J.M. Anderson and R.J. Koestler for assistance and advice. Illustrations were drawn by G.D. This work was supported by the New York Aquarium of the New York Zoological Society, while G.D. was at the New York Aquarium.  相似文献   

12.
Summary Pyrolysis of cannabidiol, one of the major constituents of Cannabis sativa, yields a mixture of components. Next to previously identified products, a major conversion product has now been isolated and identified. The unusual and stereospecific route of formation of this compound with altered chromophore is discussed.Acknowledgments. This research was supported by the Dutch Department of Public Health and Environmental Hygienics. Thanks are due to R. D. van Ooyen who provided technical assistance, Dr M. J. A. de Bie and Dr W. Heerma for valuable discussions, Drs J. W. Marsman and Ir T. Spoormaker for performing PMR experiments.  相似文献   

13.
Summary Norlobariol (I) previously described as a synthetic product derived from norlobaridone (II) was isolated as a new metabolite fromXanthoparmelia scabrosa (Tayl.) Hale.Acknowledgment. The authors wish to acknowledge the assistance of Dr D. Galloway in identifying the lichen sample and Dr A.W. Campbell for the microanalytical data.  相似文献   

14.
Summary Drosophila melanogaster adults were collected for several years in various localities of Italy. The frequencies of thePgm electrophoretic alleles were determined and the similarity of the configuration of allelic frequencies observed. It was concluded that the PGM electrophoretic polymorphism could be maintained by random genetic drift in the natural populations studied only if the effective breeding size (N e ) during the bottle-neck period is about 5000.I am grateful to Prof. D. Sperlich and Prof. W. Seyffert for their kind hospitality during my sojourn as Research Fellow of the Alexander von Humboldt Foundation in the Institute of Biology II at the University of Tübingen (FRG) where the final version of this paper has been done. The technical assistance of Mr A. Micheli is also acknowledged.  相似文献   

15.
Summary Wood frogs survive extracellular freezing at moderate subzero temperatures (–4°C) for at least 11 days. Freezing survival is aided by the accumulation of high concentrations of glucose as a cryoprotectant in blood and tissues. Glucose production was accompanied by a rapid decline in liver, but not muscle, glycogen levels suggesting that liver is the organ controlling cryoprotectant synthesis.Acknowledgments. This study was supported by grants to L.M.G. from the Kroc Foundation (Santa Ynez, California) and from the National Institute of Dental Research (Grant No. DE-03987). The authors wish to thank K. Yorko, M. Shakin, J. Finan and Mrs N. Manivannan for their technical and secretarial assistance.Acknowledgments. I thank Dr J. Ballantyne, Dr F. Schueler and I. McMurray for help with frog collections and Dr. W. Schmid, Dr J. Bogart and Dr F. Cook for helpful discussions. Supported by an N.S.E.R.C. operating grant and by a grant from the Atkinson Charitable Foundation.  相似文献   

16.
Zusammenfassung Es wird gezeigt, dass bei männlichen Wistar-Ratten im 3-Wochen-Diätexperiment mit Zusatz von 0,3% 2-Methyl-2-(p-1,2,3,4-Tetrahydro-1-naphthylphenoxy)-Propionsäure (Su-13437) die Oxydation von 26-14C-Cholesterin zu14CO2 durch Lebermitochondrien (bezogen auf mg/N) ähnlich wie bei den Kontrollen war. Bei den Versuchstieren war jedoch bei Abwesenheit von Cytosol im System die Oxydation durch Lebermitochondrien erhöht.

Acknowledgment. This work was supported, in part, by a grant No. HE-03299 and a Research Career Award No. 4-K6-HE-0734 from the National Heart Institute, N.I.H. We are indebted to Dr. W. I.Taylor, CIBA Pharmaceutical Co., Summit, N.J., for the generous gift of Su-13,437.  相似文献   

17.
Summary The biosynthetic conversion of a pyrrolizidine alkaloid (heliotrine,IV) to a male moth pheromone (hydroxydanaidal,III) is found to proceed with inversion of configuration at the remaining asymmetric center (C-7).Acknowledgments. The partial support of this research by a grant from the N.I.H. (AI-12020) and by the Deutsche Forschungsgemeinschaft (SFB4-B6) is acknowleded with pleasure.Please address correspondence regarding the chemical aspects of this communication to either T.W. Bell (Stony Brook) or J. Meinwald (Ithaca); inquiries regarding biological aspects should be sent to M. Boppré (Regensburg) or D. Schneider (Seewiesen).  相似文献   

18.
Summary Representative members in each of the four orders of Oomycetes (Phytophthora cactorum, Peronosporales;Lagenidium callinectes, L. giganteum, Lagenidiales;Saprolegnia ferax, Saprolegniales;Apodachylella completa, Leptomitales) have been examined for their ability to synthesize and polycyclize squalene-oxide (SO) to a tetracyclic product and to differentiate between cycloartenol and lanosterol metabolism to sterols.P. cactorum andL. giganteum failed to synthesize or metabolize SO, cycloartenol or lanosterol. While the other three fungi synthesized sterols via SO and lanosterol, a minor metabolism of added cycloartenol to the 4,4-desmethyl-14-methylcyclosteroid dehydropollinastanol was observed.Acknowledgment.Saprolegnia ferax-ATCC 3605 (1),Lagenidium callinectes ATCC 24973 (2),Apodachlyella completa (3) were obtained from Dr J. Aronson, Arizona State Univ. (3),Lagenidium gigateum was obtained from a drainage ditch in California (4), andPhytophthora cactorum was obtained from the U.C. Berkeley Fungal Collection (5). The fungi were cultured as previously described: Cultures 1,2,3: Berg, L. B., Ph. D. dissertation, Univ. of MD., College Park (1983); culture 4: Kerwin, J.L., and Washino, R.K., Exp. Mycol.7 (1983) 109; culture 5: Nes, W.D., and Stafford, A.E., Lipids19 (1984) 544. Preliminary observations involving the labeled substrates were presented by Le, P.H., Nes, W.D., and Parish, E.J. J. Am. Oil Chem. Soc.62 (1985) 655(A). Please address all correspondence to W.D. Nes, Plant Physiology and Chemistry Research Unit, ARS-US Dept of Agriculture, Berkeley, CA 94710, USA.  相似文献   

19.
Summary Awake, freely breathing rats subjected to moderate hypoxia (10% O2) manifest prompt tachycardia which is essentially unaffected by atropine and is blocked by propranolol, and is thus apparently mainly of sympathetic origin.This work was supported by grants from American Heart Association — Greater Los Angeles Affiliate (437IG), and National Science Foundation (GB-41390). J. D. L. was a Summer Scholar selected by the Committee for Advance Science Training. We thank Mr D. Ward and Miss L. J. Berg for much valuable assistance and Dr. J. L. Kinney for help in the statistical analysis of the data.  相似文献   

20.
Summary Disorders in the carotenoid metabolism are proposed to explain the absence of the yellow and violet or only the violet carotenoid-linked proteins from the haemolymph of someR. americana larvae. The lack of only the yellow chromoprotein is considered to be due to a failure in the biosynthesis of its apoprotein.Supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Conselho Nacional de Pesquisas (CNPq). W.R.T. and A.G. de B. are indebted to Prof.F. J. S. Lara for advice, encouragement and for laboratory facilities. We thank Mr.A. Malavasi for collecting larvae in nature, Mrs.R. M. Zanelato for larvae culture and MissI. L. Jorge for typing.  相似文献   

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