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1.
Ohne Zusammenfassung Vorgelegt von B. L. van der Waerden Herrn Professor I. I. Schafranovsky, Berginstitut Leningrad, in Dankbarkeit gewidmet  相似文献   

2.
Résumé A partir de la racine d'Asclepias amplexicaulis on a isolé un nouveau glycoside de la série prégnane, avec une potentialité d'action anti-cancer. Il possède l'aglycone: 12-cinnamoyl-20-O-acétylsarcostine. Les sucres asclépobiose et digitoxose se trouvent á C-3.

Part V of Plant Investigations. Part IV, seeD. M. Piatak andK. A. Reimann, Tetrahedron Lett.,1972, 4525; b) This work was supported by grants from the American Cancer Society (IC-26) and its Illinois Division (Seiffert Trust Fund).

We gratefully acknowledge samples of asclepobiose and sarcostin from Prof.T. Reichstein and his workers.  相似文献   

3.
Zusammenfassung Ein neues Alkaloid, Pterogynin, wurde aus der Rinde vonPterogyne nitens Tul. (Leguminosae) isoliert und seine Struktur bestimmt. Es handelt sich um das N,N-Di(isopenten-2-yl)-guanidin.

Part XIV ofStudies on Plants; proceding part, R. A.Corral, O. O.Orazi and I. A.Benages, Tetrahedron Letters545 (1968).  相似文献   

4.
Taken together with my previous articles [77], [80] devoted to the history of finite random sums and to Laplace's theory of errors, this paper sheds sufficient light on the whole work of Laplace in probability. Laplace's theory of probability is subdivided into theory of probability proper, limit theorems and mathematical statistics (not yet distinguished as a separate entity). I maintain that in its very design Laplace's theory of probability is a discipline pertaining to natural science rather than to mathematics. I maintain also the idea that the so-called Laplacian determinism was no hindrance to applications of his theory of probability to natural science and that one of his utterances in this connection could have well been made by Maxwell's contemporaries.Two possible reasons why the theory of probability stagnated after Laplace's work are singled out: the absence of new fields of application and, also, the insufficient level of mathematical abstraction used by Laplace. For all his achievements, I reach the general conclusion that he did not originate the theory of probability as it is now known. Dedicated to the memory of my Father, Boris A. Sheynin (1898–1975), the first generation of the Russian revolution Cette inégalité [Lunaire] quoique indiquée par les observations, était négligée par le plus grand nombre des astronomes, parce qu'elle ne paraissait pas résulter de la théorie de la pesanteur universelle. Mais, ayant soumis son existence au Calcul des Probabilités, elle me parut indiqués avec une probabilité si forte, que je crus devoir en rechercher la cause.(P. S. Laplace (Théor. anal. prob., p. 361))  相似文献   

5.
Zusammenfassung Curacin, die chlorhaltige Fraktion der milden Hydrolyse des Antibiotikums Curamycin, wurde durch ihre chemischen und physikalischen Eigenschaften als 4-O-Dichlor-iso-everninyl-2-deoxy-d-rhamnose aufgeklärt. Ausserl-Lyxose und 4-O-Methyl-d-fucose besitzt auch das Curamycin ein drittes Monosaccharid,d-Curamicose, welches als 2,6-Di-O-methyl-d-mannose identifiziert wurde.  相似文献   

6.
Ohne ZusammenfassungDem Andenken von Herrn Professor Joseph Ehrenfried Hofmann gewidmet Vorgelegt von J. E. Hofmann und A. P. Juschkewitsch  相似文献   

7.
Ohne Zusammenfassung B. L. van der Waerden zum 70. Geburtstag gewidmet Vorgelegt von B. L. van der Waerden  相似文献   

8.
Summary Using the properties of the Centre of Gravity to obtain geometrical results goes back to Archimedes, but the idea of associating weights to points in calculating ratios was introduced by Giovanni Ceva in De lineis rectis se invicem secantibus: statica constructio (Milan, 1678). Four years prior to the publication of Ceva's work, however, another publication, entitled Geometria Magna in Minimis (Toledo, 1674), 2 appeared stating a method similar to Ceva's, but using isomorphic procedures of a geometric nature. The author was a Spanish Jesuit by the name of Joseph Zaragoza.Endeavouring to demonstrate an Apollonius' geometrical locus, Zaragoza conceived his idea of centrum minimum — a point strictly defined in traditional geometrical terms — the properties of which are characteristic of the Centre of Gravity. From this new concept, Zaragoza developed a theory that can be considered an early draft of the barycentric theory that F. Mobius was to establish 150 years later in Der barycentrische Calcul (Leipzig, 1827).Now then, whereas Ceva's work was rediscovered and due credit was given him, to this day Zaragoza's work has remained virtually unnoticed.  相似文献   

9.
Summary The males of two species of Palestine,Saga ephippigera Fisch. andS. gracilipes Uvar have respectively 33 and 31 chromosomes in the diploid state.S. pedo Pallas, a parthenogenetic thelytoc species largely distributed in Europe, has 68 chromosomes and probably represents a tetraploid. The cells of the three species have identical dimensions and the polyploidS. pedo is even the smallest in size.  相似文献   

10.
Zusammenfassung Acetonextrakt aus Wurzeln und Rhizomen vonIris ensata hemmen die Metamorphose vonDysdercus koenigii. Adultoide sind schwach fortpflanzungsfähig.

Acknowledgments: The authors are thankful to Dr.K. Ganapathi, Director, and Dr.A. Husain, Chairman, Discipline of Agricultural Sciences, Regional Research Laboratory, Jammu-Tawi, for the facilities provided for this work. Thanks are also due to Mr.Y. K. Sarin, Incharge, Plant Collection Unit, of the same laboratory for she identification and collection of the plant material.  相似文献   

11.
Summary Voacryptine is demonstrated to be 20-oxovoacangine. On reduction, it furnishes voacristine (20-hydroxyvoacangine) and 20-epi-voacristine.

3. Mitt.U. Renner undD. A. Prins, Exper.15, 456 (1959).  相似文献   

12.
Ohne ZusammenfassungHerrn Prof. Dr. h. c. Dr. J. E. Hofmann zum 65. Geburtstag gewidmet Vorgelegt von A. Youschkevitch  相似文献   

13.
Summary The catalysis of H2O2 decomposition by Cu2+-complexes of RNA and DNA has been investigated. It is shown that both complexes decompose H2O2, but only the Cu2+-RNA-system shows peroxidative activity too, e.g. only in this case the nucleotide bases are degraded. Thermal denaturation of DNA also leads to a Cu2+-complex with peroxidative activity, the latter being dependent on the degree of denaturation.

V. Mitteilung:S. Petri, H. Sigel undH. Erlenmeyer, Helv. chim. Acta49, 1778 (1966).

12. Mitteilung überMetallionen und H 2 O 2; 11. Mitteilung:H. Ch. Curtius, P. Anders, R. Zell, H. Sigel undH. Erlenmeyer, Helv. chim. Acta49, 2256 (1966).  相似文献   

14.
Zusammenfassung Die Einführung einer Hydroxylgruppe in die 21-Stellung gewisser Pregnanderivate mittelsAspergillus niger ATCC 9142 wird beschrieben.

Paper LXV,J. Iriarte, G. Rosenkranz, andF. Sondheimer, J. Org. Chem. (in press).  相似文献   

15.
Zusammenfassung Charakterisierung und Strukturaufklärung eines neuen Alkaloides, Thalrugosamin ausThalictrum rugosum.

Acknowledgment. The authors are indebted to the Warren-Teed Division of Rohm and Haas and the NIH (No. AI 09846) for financial support,Rodger White (Warren-Teed) andFrank W. Denison (Abbott Laboratories) for biological data andRueyping Leu for expert technical assistance.  相似文献   

16.
Résumé L'examen cytologique de la descendance de 2Xenopus borealis révéla 50% d'individus dotés de noyaux à 1 et 2 nucléoles (situation normale) et 50% à 1, 2 et 3 nucléoles. Le caryotype de ces derniers démontra la présence de 3 organisateurs nucléolaires, au lieu de 2, l'origine de l'élément supplémentaire relevant d'une translocation réciproque entre 4 et 7.

Supported by a grant (No. 3.60.68) from the Fonds national suisse de la Recherche Scientifique and the George and Antoine Claraz donation.

Unpublished research in this laboratory has shown thatXenopus laevis borealis (Parker) is a species on its own right and we propose to name itXenopus borealis (Parker).

Material collected byFischberg andKobel, who express their gratitude to the Fisheries and Game Dept. of Kenya for permission to collect frogs of the genusXenopus.

Acknowledgments. The authors wish to thank Mrs.J. Tymowska and MissE. Ackermann for their technical advice; they are grateful to Mr.J. Jackson, MissM. C. Payot, MissL. Ricard and Mr.P. Grutter for their assistance and useful help.  相似文献   

17.
Ohne Zusammenfassung Vorgelegt von A. P. Youschkevitch  相似文献   

18.
Zusammenfassung Es gibt bemerkenswerte Unterschiede der Karyotypen vonMuntiacus muntjak vaginalis undM. m. muntjak. Jeder hat einen unterschiedlichen DNA-Wert, aber beide Werte sind niedriger als diejenigen des Menschen. Die Karyotypen-Evolution ist nicht abgeklärt, aber die Befunde zeigen, dass eine taxonomische Revision notwendig ist.

We thank CaptainIllar Muul (U. S. Army Medical Research Unit, Kuala Lumpur) for donation of the skin biopsy ofMuntiacus muntjak muntjak, andK. Imredy, B. Bacon andM. Larson for technical assistance. Supported by NIH Grant No. HD 03298.  相似文献   

19.
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   

20.
Communicated by B. L. van der Waerden  相似文献   

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