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Asiatic cobras: systematics and snakebite   总被引:1,自引:0,他引:1  
W Wüster  R S Thorpe 《Experientia》1991,47(2):205-209
The population affinities of the Asiatic cobras of the genus Naja are investigated, using multivariate analysis of a range of morphological characters. This complex, which was formerly thought to be monospecific, consists of at least eight full species. In some cases, species whose bites require different antivenoms occur sympatrically. The new understanding of the systematics of the Asiatic cobra complex calls for a reappraisal of cobra antivenom use in Asia, and for more research into venom composition.  相似文献   

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J M Lowenstein  O A Ryder 《Experientia》1985,41(9):1192-1193
It has been debated whether the extinct quagga was a distinct fourth species of African zebra or whether it was merely the southern variant of the Plains zebra (Equus burchelli). Using a radioimmunoassay (RIA) technique, we have shown that proteins remaining in quagga skins from museums are much more similar to serum proteins of the Plains zebra than to those of the other two extant zebras.  相似文献   

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Summary It has been debated whether the extinct quagga was a distinct fourth species of African zebra or whether it was merely the southern variant of the Plains zebra (Equus burchelli). Using a radioimmunoassay (RIA) technique, we have shown that proteins remaining in quagga skins from museums are much more similar to serum proteins of the Plains zebra than to those of the other two extant zebras.  相似文献   

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Summary It was possible to separate species and complexes of species in theReticulitermes genus of Western Europe using esterase 3 and acid phosphatase 2.  相似文献   

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Résumé Les protéines solubles de la lentille et des muscles des oiseaux furent examinés au moyen de la micro-électrophorèse en agargel. La mobilité des fractions protéiques s'est présentée comme un caractère systématique important: il y a généralement des différences nettes et constantes, mais parfois aussi des ressemblances, qui indiquent probablement des relations de parenté.  相似文献   

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Advances in methods of structure determination have led to the accumulation of large amounts of protein structural data. Some 500 distinct protein folds have now been characterized, representing one-third of all globular folds that exist. The range of known structural types and the relatively large fraction of the protein universe that has already been sampled have greatly facilitated the discovery of some unifying principles governing protein structure and evolutionary relationships. These include a highly skewed distribution of topological arrangements of secondary-structure elements that favors a few very common connectivities and a highly skewed distribution in the capacity of folds to accommodate unrelated sequences. These and other observations suggest that the number of folds is far fewer than the number of genes, and that the fold universe is dominated by a small number of giant attractors that accommodate large numbers of unrelated sequences. Thus all basic protein folds will likely be determined in the near future, laying the foundation for a comprehensive understanding of the biochemical and cellular functions of whole organisms.  相似文献   

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Zusammenfassung Die Zahl der diploiden Chromosomen vonMarmota caligata undM. flaviventris ist 42 in Bevölkerungen der nördlichen und südlichen Verbreitungsgebiete beider Spezies. Ein Vergleich zwischen den bisher veröffentlichten Informationen überMarmota-Chromosomen mit Angaben über ihre Morphologie, Ekologie, Zoogeographie legt nahe, dass die ursprüngliche Chromosomenzahl 2n 38–40 war.

Supported by National Science Foundation Grant Nos. GB-3251 and GB-5428, and by a National Academy of Sciences US-USSR Exchange Fellowship. We thank Dr.D. L. Pattie for generously providing the specimen ofM. flaviventris and Mrs.Gabriele Forrester for preparation of theM. c. nivaria chromosomes.  相似文献   

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Zusammenfassung Zur Erhärtung der oft formulierten Vermutung, dass hochbegabte Kinder meistens von älteren Eltern abstammen, wurde eine Serie von Untersuchungen durchgeführt an verschieden zusammengestellten Listen hervorragender Persönlichkeiten. Dabei stellte sich als wertvoll heraus, neben dem Alter des Vaters auch die Alter der beiden Grossväter heranzuziehen und die Summe dieser 3 Alter, die «väterliche Dreierzahl» zu benutzen. Im Resultat ergibt sich, dass die Alter der Väter unter 30 nur in weniger als 20% aller Fälle und zugleich «Dreierzahlen» unter 90 in weniger als 5% aller Fälle vorkommen. Die Hypothese, dass allgemein der IQ im Durchschnitt monoton mit der «Dreierzahl» wächst, wurde an einer Gruppe von 87 Schülern eines Gymnasiums getestet und durch den «Spearman rank correlation test» als signifikant mit der Fehlerwahrscheinlichkeit unter 4% nachgewiesen. Eher unerwartet, scheint das Alter des väterlichen Grossvaters stärkeres Gewicht zu haben als das des leiblichen Vaters.

I should like to express my gratitude to ProfessorEduard Batschelet, Biomathematisches Institut der Universität Zürich, and ProfessorAlexander M. Ostrowski, Mathematisches Institut der Universität Basel, who both helped me in a very kind way with the significance computations and made many useful observations.

Dedicated toAlexander M. Ostrowski on his 80th birthday.  相似文献   

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Summary The author reviews the background of the soil-cancer relationship. The study then goes into geocarcinogenic diseases in relation to soil composition, looking first at general factors: soil concentrations of selenium, caesiumrubidium-potassium, trace elements; natural radioactivity risks; cancer risks in connection with recycled waste water. In its final part, the study examines geocarcinogenic diseases linked with soil composition covering gastric cancer, cancer of the esophagus, urinary, breast, and bronchial cancer, pleural mesotheliomae and bone cancer.  相似文献   

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E G Peeters 《Experientia》1987,43(1):74-81
The author reviews the background of the soil-cancer relationship. The study then goes into geocarcinogenic diseases in relation to soil composition, looking first at general factors: soil concentrations of selenium, caesium-rubidium-potassium, trace elements; natural radioactivity risks; cancer risks in connection with recycled waste water. In its final part, the study examines geocarcinogenic diseases linked with soil composition covering gastric cancer, cancer of the esophagus, urinary, breast, and bronchial cancer, pleural mesotheliomae and bone cancer.  相似文献   

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The nineteenth-century American scientist, philosopher and teacher Joseph LeConte (1823–1901) is well-known for his writings on geology and the reconciliation of evolutionary theory and religion, but he has not been properly recognized for his contributions to the physiology and psychology of vision. This study explores and assesses his work in the latter field, showing the nature of his original investigations into human vision and the influence of his book Sight: an exposition of the principles of monocular and binocular vision, which served as the major textbook on the subject in the United States from its publication in 1881 until after the turn of the century. Grounded in neo-Lamarckian evolutionary theory, LeConte's publications on vision had a strong impact upon subsequent studies of the phenomenon of human sight.  相似文献   

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Zusammenfassung Hitze und Histamin vermögen eine Kontraktion der Endothelzellen feiner Venen zu erzeugen. Hitze und Histaminschädigung des Mäusezwerchfells (Endothelfensterung) führt zu Kontraktionen von Endothelzellen und Mesothelialzellen. Venalot, ein Produkt aus Cumarin und Trihydroxyethyl-Rutin, vermag das Oedem zu beseitigen.

This work was partly supported by the Australian Research Grants Commission and by Schaper and Brümmer, Salzgitter-Rigelheim, Western Germany. We are most grateful for the skilful assistance of MissJ. R. Daymond and MessrsK. W. Crocker andH. F. W. Ehman.  相似文献   

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