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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 Chemical analysis of lamprey cartilage showed that its major constituent was a newly defined structural protein termed lamprin. Amino acid analysis of lamprin revealed that it has a unique composition which is distinct from previously identified structural proteins.Acknowledgment. This work was supported by grants U0105 to G.M.W. and A5945 to J.H.Y. from the Natural Sciences and Engineering Research Council of Canada.  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 Abscisic acid, a plant growth hormone, added in water to the grass diet of a grasshopper, greatly reduces the reproductive rate, as does gibberellin A3 at doses 10 times greater. Reciprocal seasonal variations in quantities of these hormones could synchronize the growth and reproduction of insects with their host plants in the field.Acknowledgments. I thank Drs J. Pickett, G. Strobel, D. Meyers, I. Mills, L. Jackson and J. Bradbury for helpful consultations; Dr R. Lund and Ms W. Whitmore for statistical analyses, and S. Baril, M. Gaudet, D. Wrobetz, J. Cotter and W. Wallace for technical assistance. This research was supported by the Montana Agricultural Experiment Station, Project 420, and is published as Journal Paper No. 865.  相似文献   

5.
Summary The amnesic effects of 2 benzodiazepine drugs, diazepam (Valium) and lorazepam (Ativan), have been investigated. Some of the effects were similar to those of certain clinical amnesic syndromes. The effects were more extensive than previous work has indicated.Acknowledgments. The authors are grateful to Dr J. Hope and Dr D. Gosh for clinical assistance and to Dr T.V.A. Harry of John Wyeth and Brother Ltd, Dr W.H. Franklin of Roche Products Ltd and Professor J.B. Chappell for advice and discussion. We thank John Wyeth and Brother Ltd for financial support and for supplying lorazepam.  相似文献   

6.
Summary Ovulation in tsetse flies is normally induced by mating, but virgins can be stimulated to ovulate with an injection of dibutyryl cyclic AMP, cholera toxin (a cyclic AMP generator), or aminophylline (a phosphodiesterase inhibitor). Thus, elevation of cyclic AMP is a likely link in the events leading to ovulation.We thank J. de Wilde and W.A. Foster for helpful comments. D.L.D.'s research visit to ICIPE was supported by a grant from the Mid-West Universities Consortium for International Activities.  相似文献   

7.
Summary In two arctiid species,Holomelina lamae andH. aurantiaca, which rhythmically extrude and retract their abdominal tips during pheromone emission, pheromone glands contain up to three orders of magnitude more of the major component than in most Lepidoptera examined to date. Using an effluent collection technique, relatively high rates of pheromone emission were obtained from freely calling females. In contrast, volatilization rates from forcibly extruded glands were about 25 times lower for both species, suggesting that pulsation of the gland functions to increase the release rate.We thank R. Charlton, R. Collins, J. Tang and R. Webster for valuable discussions D. Smith for drawing of the figure, and Dr Robert W. Astheimer of Barnes Engineering for generously donating his time and an IR Microscope used in remote temperature measurements.  相似文献   

8.
Summary British common shrews of the Aberdeen, Oxford and Hermitage Robertsonian karyotypic races were hybridized successfully in captivity. Hybrids, both simple Robertsonian heterozygotes and double Robertsonian heterozygotes with monobrachial homology, have been identified in an area of contact between the Oxford and Hermitage races. The relative fertility of these two types of hybrid is considered.I thank Dr. C. E. Ford F. R. S., Prof. F. W. Robertson and Dr A. E. Douglas for reading earlier drafts of this paper, Prof. F. W. Robertson, Dr J. R. K. Savage and Dr J. R. Clarke for laboratory facilities, Mrs J. E. Evans for technical assistance and S.E.R.C. for financial support.  相似文献   

9.
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   

10.
Summary 2-{benzoylamino} pyridinium benzoate (BAPB) has exhibited an antisickling effect with homozygous S/S erythrocytes in vitro. This study suggests that BAPB prevents sicklin by inhibiting the gelation of hemoglobin S.Acknowledgments. This research has been partly funded by a Sickle Cell Research grant from the State of Tennessee to Meharry Medical College. We gratefully appreciate the technical assistance of Mr Rudolf Harlan and Mrs Marjorie Deveau of the School of Graduate Studies. We offer our thanks to Dr J. W. Davis, J. D., Coordinator, Sickle Cell Project, Meharry Medical College for constant encouragement.  相似文献   

11.
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   

12.
Summary Detailed ecological studies of some maritime populations of Lotus corniculatus L. have shown that the distribution of the cyanogenic form of this plant is directly related to the distribution and density of molluscs which graze selectively the acyanogenic form. This work, on a genetic polymorphism, is interpreted as giving direct evidence of chemical defence in natural populations.Acknowledgment. We are most grateful to the Science Research Council (B/RG/3539, W.M.E. and D.A.J.) and to the Natural Environment Research Council and the Sir Philip Reckitt Educational Trust (research studentship, R.J.K.) for the financial support of this work.  相似文献   

13.
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   

14.
Summary The effects of visual and auditory cues on mating behavior was examined for 2 members of theDrosophila nannoptera species group. Results indicate that visual and auditory signals do not play a significant role in mating success inDrosophila acanthoptera andD. species W.Acknowledgments. This study was supported by a Division of Research Resources-National Institute of Health, Minority Biomedical Support grant (RR 07152-04) awarded to M.C.J. The grant provides a stipend for E.S.G. who is completing requirements for her Master of Science degree in Biology. Send reprint requests to M.C.J.  相似文献   

15.
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   

16.
Summary Approximately 180 small and mainly acrocentric chromosomes are present inGeotria australis (Geotriidae) from the southern hemisphere. This is closer to the situation found in northern hemispheric species (Petromyzonidae) than in other southern hemispheric lampreys (Mordaciidae).We wish to express our gratitude to Mr R. W. Hilliard and Mr D. J. Bird for technical help. Financial assistance was provided by the Australian Research Grants Committee.  相似文献   

17.
Summary 2 yellow naphthoquinone derivatives were isolated from several pathogenic strains ofHendersonula toruloidea Nattrass. They were identified as 2,7-dimethoxy-6-ethyl-5-hydroxy-1,4-naphthoquinone and 2,7-dimethoxy-5-hydroxy-6-(1-acetoxyethyl)-1,4-naphthoquinone by means of physico-chemical methods.Thanks are due to Mr A.J.M. van Beijnen, Laboratory for Organic Chemistry, State University of Utrecht, for optical rotation measurements.The authors are indebted to Mr C. Versluys, Analytical Laboratory, State University of Utrecht, for measuring the mass spectra.We thank Mr J. W. Marsman, Institute for Organic Chemistry TNO, Utrecht, for the PMR-spectra.  相似文献   

18.
Summary The rise in serum luteinizing hormone concentration after treatment with gonadotropin-releasing hormone was less in diabetic castrated male rats than control castrates. In intact male rats, gonadotropin-releasing hormone treatment resulted in higher serum luteinizing hormone concentrations in diabetic than in control rats.Acknowledgments. This work was supported in part by a grant from the Medical Research Council of Canada. The authors are grateful to Dr G.D. Niswender, Dr L.E. Reichert, Jr. and the National Institute of Arthritis, Metabolism and Digestive Diseases, Rat Pituitary Hormone Program for providing radioimmunoassay materials. The streptozotocin was kindly provided by Dr W.E. Dulin, The Upjohn Company. D.B. Beaton and J. Brunka provided excellent technical assistance.  相似文献   

19.
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   

20.
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   

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