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1.
Summary A characteristic and reproducible sign of narcotic withdrawal is the naloxone induced increase in arterial pressure. In morphine-dependent rats allowed to undergo spontaneous withdrawal (6–24 h) and then transected at the spinal C-1 level, arterial pressure was maintained at a significantly higher level than either spinal-transected nondependent controls or morphine-dependent, spinal-transected rats pithed from C-1 to L-4. These findings indicate that the morphine-dependent spinal cord, independent of supraspinal influences, is able to exhibit an autonomic component of spontaneous withdrawal.This study was supported by the Medical Research Service of the Veterans Administration. A preliminary report of aspects of this work appeared in Soc. Neurosci. Abs.10 (1984) 1113.  相似文献   

2.
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   

3.
Summary Reserpinine, a minor alkaloid ofRauwolfia serpentina Benth. accompanying Reserpine, has been isolated, and its structural formula is proposed.

10. Mitteilung über Rauwolfia Alkaloide. — 9. Mitteilung sieheF. Bader, D. F. Dickel undE. Schlittler, Amer. Soc.76 (1954) (im Druck).  相似文献   

4.
Zusammenfassung Aus der Rinde des brasilianischen BaumesAspidosperma dasycarpon A. DC. wurden fünf neue Alkaloide (II–VI) isoliert, die das selten vorkommende Uleinskelett besitzen. Die Strukturen wurden durch chemische Korrelation mit Ulein (I) sichergestellt.

Paper XLVII in the seriesAlkaloid Studies. For paper XLVI seeK. S. Brown Jr. andC. Djerassi, J. Am. chem. Soc.86, in press (1964).  相似文献   

5.
Zusammenfassung Die Synthese des Naturstoffes Tetrahydroseselin aus der FruchtSeseli indicum wird beschrieben.

Part X of a seriesCoumarins and Related Compounds. Part IX, A. K.Das Gupta, R. M.Chatterje and K. R.Das, J. chem. Soc. (C), (1969), 2618.  相似文献   

6.
Summary The defensive secretions of male and femaleOodes americanus display striking qualitative differences. Altogether 13 carboxylic acids were identified in the secretions of the two sexes. Methacrylic, crotonic, and tiglic acids are produced exclusively by the female; the male lacks these unsaturated components, but produces their saturated analogs. 2-Methylbutyric acid is a major component produced by both sexes. Shared components also include hexanoic, (E)-2-hexenoic, benzoic, and (E)-2-octenoic acid, of which the latter two had not previously been reported from carabid beetles.Paper no. 98 in the series Defense Mechanisms of Arthropods; no. 97 is by Smedley et al., J. Lepid. Soc., in press.  相似文献   

7.
Zusammenfassung Mit Hilfe der PM-Methode ist die molekulare Rotation von (–)-1,2/3,4-Cyclohexantetrol untersucht worden. Daraus geht hervor, dass diese Verbindung in wässeriger Lösung als Gemisch der C 1- und 1 C-Konstellationen vorliegt.

Part III. Part II, seeS. Yamana, Bull. chem. Soc. Japan34, 1212 (1961).  相似文献   

8.
Zusammenfassung Auf Grund von Protonresonanz und massenspektrometrischen Messungen sowie durch direkte Verbindung mit Pyrifolin (II) wird für dasAspidosperma-Alkaloid Aspidofilin die Struktur III vorgeschlagen.

This paper represents part XXXVII. For preceding paper seeH. Vorbrueggen andC. Djerassi, J. Amer. chem. Soc.84, in press (1962).

Recipient of a fellowship from the International Cooperation Administration under a program administered by the U.S. National Academy of Sciences.  相似文献   

9.
Larvae of two insects, a coccinellid beetle (Hyperaspis trifurcata) and a chamaemyiid fly (Leucopis sp.), feed on cochineal insects and appropriate their prey's defensive chemical, carminic acid, for protective purposes of their own.H. trifurcata discharges the chemical with droplets of blood (hemolymph) that it emits when disturbed;Leucopis sp. ejects the compound with rectal fluid. Ants are thwarted by these defenses, which are compared with the previously-described defense of a pyralid caterpillar (Laetilia coccidivora) that disgorges carminic acid-laden crop fluid. The defensive fluid of all three larvae contains carminic acid at concentrations spanning a range (0.2–6.2%) proven deterrent to ants. Many insects are known to appropriate defensive substances from plants. Insects that acquire defensive chemicals from animal sources may be relatively rare.Paper No. 124 in the series Defense Mechanisms of Arthropods; No. 123 is Epstein et al., J. Lepid. Soc. (in press).  相似文献   

10.
Summary Twenty-one alkaloids have been identified from the root ofRauwolfia ligustrina R. & S. The more important ones are reserpine, pseudoreserpine and raugustine, a new base which is isomer to pseudoreserpine. The structure of the latter compound is discussed.

Mitteilung über Rauwolfia-Alkaloide

Mitteilung sieheC. F. Huebner undE. Schlittler, J. Amer. chem. Soc.79, 250 (1957).  相似文献   

11.
Summary 1,1-Dimethyl-5,6-dihydroxyindolinium chloride (1a)was identified from a deep water sample of the marine sponge,Dercitus sp., and its structure was elucidated by spectral methods.Acknowledgments. This is Harbor Branch Oceanographic Institution, Inc., SeaPharm Project Contribution No. 612. We thank Drs K. Rinehart, Jr, S. Pomponi and E. Armstrong for sponge collection.  相似文献   

12.
Zusammenfassung Die viruzide Wirkung von Extrakten aus Ahornsamen auf Coli-Bakteriophagen ist durch Tannine bedingt. Verschiedene Gerbstoffe zeigen einen zum Teil sehr starken virushemmenden Effekt, wobei nur das extrazelluläre Virus angegriffen wird. Wahrscheinlich handelt es sich um eine Gerbwirkung auf das Protein des Virus.Die pflanzlichen Gerbstoffe tragen vermutlich dazu bei, die Pflanzensäfte virusfrei zu halten.

While this paper in print, our attention was called to a recent publication in J. Bact. (66, 572 1953) byCarson andFrisch about the growth inhibiting action of tannic acid on influenza virusin ovo. We were ignorant of this work and of the previous publication from 1948 byGreen, Proc. Soc. Exptl. Biol. Med.67, 483 (1948).  相似文献   

13.
Zusammenfassung Dregamine, ein neues Alkaloid aus der ApocynaceaeVoacanga dregei E. M. wurde isoliert und charakterisiert. Diese Verbindung stellt einen neuen Vertreter der Klasse der 2-Acyl-indole dar.

Alkaloids of Apocynaceae III,M. Gorman, N. Neuss, J. A. Deyrup, andN. J. Cone, J. Amer. chem. Soc. (1959), in press.  相似文献   

14.
Branch internodes ofMurraya paniculata flowered in vitro on half-strength MT medium containing 5% sucrose supplemented with cytokinins. The cytokinins only induced vegetative shoots from the epicotyl of seedlings. The highest percentage of flowering (76.7% of the explants) was achieved from branch internodes of flowering plants close to the apex, on half-strength MT medium containing 5% sucrose and 0.001 mg l1 benzyladenine (BA) in light. Flowering required two days' exposure to BA, but shoot formation could be initiated even without exposure to BA.  相似文献   

15.
Résumé Les auteurs ont mesuré les vitesses de réaction entre l'ajmaline plus dérivés et l'iodure d'éthyle. Les conclusions stéréochimiques deTaylor au C-21 en ont été confirmées.

For previous papers on rates of quaternary iodide formation of alkaloids see (a)M. Shamma and J. B. Moss, J. Amer. chem. Soc.83, 5038 (1961) and (b)M. Shamma andE. F. Walker Jr., Chem. & Ind.1962, 1866.

Acknowledgments. The authors wish to thank Dr.W. I. Taylor of CIBA Pharmaceutical Company for the generous gift of the compounds used in this study, and the National Institutes of Health (Grant No. GM-10608-01) for financial assistance.  相似文献   

16.
    
Summary The isolation and structure determination of 9(15)-africanene (1) from the soft coralSinularia polydactyla is described.For part XXXVII, see: J. C. Braekman, D. Daloze, G. Hulot, B. Tursch, J. P. Declercq, G. Germain and M. Van Meerssche, Bull. Soc. Chim. Belg.87, 917 (1978).King Leopold III Biological Station (Laing Island, Papua-New Guinea): Contribution No. 15.Acknowledgment. We thank Prof. Y. Kashman for sending us preliminary information on his work and for a sample of the ketone. We thank also Dr Verseveldt for the identification of the animal, Mr J. Pierret for his participation in its collection and Dr G. Aranda for the CD measurement. We gratefully acknowledge the help of the FRFC for the purchase of the diffractometer.  相似文献   

17.
Zusammenfassung Die Struktur eines durch säurekatalytische Isomerisation von Ambreinolid entstehenden tricyclischen Ketons C17H26O wurde aufgeklärt.

Therpenes III.

Part II,G. Büchi andR. E. Erickson, J. Amer. chem. Soc.76, 3493 (1954).  相似文献   

18.
Summary A new piperidine derivative, the 2-diphenylmethylpiperidine, produces already in doses of 0.001 g/kg s.c. a strong increase of the spontaneous motility of various animals. On mice it has about the same potency as d-desoxy-ephedrine and is about 3 times more potent than amphetamin. It also acts markedly antagonistic on various narcotics but has practically no peripheral sympathomimetic effects.

8. Mitteilung über Alkylenimin-Derivate. 7. Mitteilung sieheB. M. Iselin undK. Hoffmann, J. Am. Chem. Soc.76 (im Druck).  相似文献   

19.
Mitochondrial cytochrome b (cyt b) from 25 out of 31 extant goldfinches, siskins, greenfinches and redpolls (genus Carduelis) has been sequenced from living samples taken around the world, specimens have also been photographed. Phylogenetic analysis consistently gave the same groups of birds, and this grouping was generally related to geographical proximity. It has been supposed that Pleistocene glaciations played a crucial role in the origin of extant diversity and distribution of Northern Hemisphere vertebrates. Molecular comparison of most extant songbird species belonging to the genus Carduelis does not support this assertion. The fossil record of chicken and pheasant divergence time has been used to calibrate the molecular clock; cyt b DNA dendrograms suggest that speciation in Carduelinae birds occurred during the Miocene and Pliocene Epochs (9 – 2 million years ago) in both the Northern and Southern Hemispheres. Only about 4% average amount of nucleotide substitution per lineage is found between the most distant Carduelis species; this suggests a remarkably rapid radiation when compared with the radiation of other passerine songbird genera. In addition, a continuum of small songbird speciation may be found during the Miocene Epoch in parallel with speciation of other orders (i.e. Galliformes, chicken/pheasant). Pleistocene glaciations may have been important in subspeciation (i.e. Eastern European grey-headed goldfinches/Western European black-headed goldfinches) and also in ice-induced vicariance (isolation) (i.e. siskin in Western Europe vs. siskin in Far East Asia) around the world. European isolated Serinus citrinella (citril finch) is not a canary, but a true goldfinch. South American siskins have quickly radiated in the last 4 million years coinciding with the emergence of the Isthmus of Panama; probably, a North American siskin related to C. notata invaded a suitable and varied biotope (the South American island) for Carduelis birds. North American goldfinches may be renamed as siskins, because they have a distant genetic relationship with European goldfinches. Genus Acanthis could be dropped, and thus redpolls should be separated from twite and linnet, the latter (Europeans) probably being related to American goldfinches. Also, reproductive barriers are observed between closely related species and not between other more distant ones. Finally, a tentative classification for genus Carduelis species is suggested. Received 6 March 1998; received after revision 3 July 1998; accepted 7 July 1998  相似文献   

20.
Zusammenfassung Dem phenolischen Oxydationsprodukt, das beim Durchleiten von Sauerstoff durch geschmolzenestrans-Dekahydrochinolin entsteht, wird auf Grund der Analyse und spektrophotometrischen Daten die Konstitution III eines 3-Oxy-5, 6, 7, 8-tetrahydrochinolins beigelegt. Seine Entstehung erfolgt wahrscheinlich über das gleichfalls gebildete 5, 6, 7, 8-Tetrahydrochinolin.

Oxidation Mechanisms. XIV. Preceding paper:B. Witkop andS. Goodwin, J. Amer. Chem. Soc.76, 1954, in press.  相似文献   

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