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1.
Summary Scarites buparius has 2n=37 and n=17+X1X2Y. This multiple sex-chromosomes system seems to be the result of a reciprocal translocation between the primitive X-chromosome and an autosome. This is the first caraboid beetle, exceptingCicindela spp., that has multiple sex-chromosomes.This work has been supported by a grant of the Comisión Asesora de Investigación Científica y Técnica, No. 1.552.  相似文献   

2.
Summary Somatic chromosome complements of the Indian burrowing toad,Uperodon globulosum, have been described for the first time. The 2n number is 26 (NF=52) in both the sexes. No heteromorphism in relation to sex chromosome pair has been recorded. Deviations from 2n number (2n=10–28) have been noticed in the cells of different specimens. The result has been compared withU. systoma.Acknowledgment. Sincere thanks are due to Prof. P. K. Ghosh, Hooghly Mohsin College and to Dr A. K. Roy of the same college for encouragement. Thanks are due to Mr Bipul Kumar Das for his help during collection of specimen.  相似文献   

3.
Summary Rana amurensis coreana, R. plancyi chosenica, R. latouchii, R. narina andOoeidozyga laevis have 2n=26 chromosomes,R. kuhlii has 2n=22, andKaloula picta has 2n=28. Males ofR. narina have a conspicuous heteromorphic pair, No. 8, which might play a rôle in sex-determination.Supported in part by a grant from the Japan-American Scholarship Foundation.I wish to thank Dr H.K. Kim, Dr Y.-S. Liang, Dr V. Samson-Carino, Mr C.-S. Wang, Mr P.S. Lin and Mr B. Durusan for their aid in every aspect during the collecting trips.  相似文献   

4.
Resumen En el murciélagoArtibeus lituratus lituratus el nÚmero de cromosomas es de 2n=30 en la hembra y de 2n=31 en el macho. El mecanismo de determination del sexo esXX/XY 1Y2. La translocación de un autosoma alX resultó en la diferenciación del neo-Y. Son descritos los aspectos del comportamiento del trivalente sexual durante la meiosis. Estos son comparados a los que presenta la especieNoctilio leporinus (2n=34) cuyo mecanismo esXX/X Y.

This work was supported by Public Health Service Research Grant No. GM-14577-03 from the National Institute of General Medical Sciences and by the Fundo de Pesquisas do Instituto Butantan. R. F. B. holds a FAPESP training fellowship.  相似文献   

5.
Zusammenfassung Von den Blutzellen derPhallusia mamillata Cuvier zeigen nur die stark vakuolisierten (compartment cells) im UV-Licht eine stabile blaue Fluoreszenz ( max =5200 und 4600 Å). Sie ist in den Zellgranula lokalisiert. Bei den Blutzellen vonCiona intestinalis L. tritt dagegen eine gelbe Fluoreszenz ( max = 5900, 5200 und 4600 Å) auf, die nur von den Vanadocyten ausgeht. Diese Fluoreszenz, welche auch von den Testazellen der Oocyten gegeben wird, geht innerhalb einiger Minuten in die blaue Fluoreszenz über.

This work has been carried out in the Stazione Zoologica, Napoli (director Dr.P. Dohrn) and in the Istituto di Biologia Generale e Genetica della Università di Napoli (director Prof. Dr.B. de Lerma). —M. de Vincentiis wishes to thank Dr,P. Dohrn for placing at his disposal a working place of the Consiglio Nazionale delle Ricerche, Roma. —W. Rüdiger thanks sincerely the Deutsche Forschungsgemeinschaft, Bad Godesberg, for providing grants, and Prof. Dr.H.-J. Bielig for his interest.  相似文献   

6.
This paper examines how a Bayesian decision maker might update her distributions for continuous variables Xi, i=1, 2, …, upon hearing experts' forecasts expressed as quantiles. To utilize the relationship between the decision maker and experts, and to avoid problems associated with different scales and ranges of the variables, we assume that the decision maker transforms the experts' quantiles in terms of her own prior distribution for each Xi. A model using such a transformation is presented and its properties are examined.  相似文献   

7.
Summary The author treats 2 topics connected with his studies on the cytogenetics of the African pigmy-mice. (1)Mus (Leggada) bufo Th. shows the primitive complement already detected in other species or subspecies (minutoides ssp 1,indutus, tenellus, setulosus): 2N=36,N.F.=36, sex chromosomesPR. (2) The deletion of the short arm of oneX-chromosome (X dc ) was previously observed as heterozygous mutation by 4 in a sample of 7 and 5 . A more important sample (18 , 21 ) gives the following results: 11 X-X, 10 X-X dc , 18 X-Y. The occurrence of X dc -X dc and of X dc -Y is also very improbable. It is not easy to understand how the chromosomeX dc may persist in the population if the complementsX dc -X dc andX dc -Y are lethal, which seems to result from these observations.  相似文献   

8.
Summary To the 237 pigmy-mice studies in his previous papers, the author brings new data concerning the cytogenetics of 25 Leggada. One first set of 12 mice from Nigeria belongs to the same polymorphic series containing themusculoides from the Ivory Coast and the Central African Republic.A small sample from Ippy (Central African Republic), although the individuals are morphologically all alike and referable tomusculoides, shows an amazing diversity: /259.2N=28, N.F.=36, sex chromosomes of the translocated type (TR). We meet here a new robertsonian combination in the polymorphic series, 34/33/32/31 ... 28/... 22/... 19/18./260.2N=32, N.F.=36, sex chromosomesTR. Both big biarmed autosomes are metacentric — submetacentric with a centromeric index of about 0.25 by the typicalmusculoides having the same diploid number./261.2N=19, N.F.=36, sex chromosomesX/Y 1 Y 2. The first occurrence of such sex chromosomes by the Leggada. By themusculoides from Rhodesia we were dealing with the typeX 1 X 2 /Y. /262.2N=18, N.F.=36, sex chromosomesX/X. Very likely the female of /261.In the complexminutoides-musculoides, we meet many different caryotypes and it is obvious that the chromosomal mutations play here the part of a primary factor of isolation, previous to the gene mutations which later will allow the taxonomic determination of the species actually in statu nascendi.  相似文献   

9.
Summary The karyotypes of two Insectivora species from Taiwan are described here for the first time.Soriculus caudatus fumidas has 2n=40 chromosomes, FN=52 andAnourosorex squamipes yamashinai has 2n=50 chromosomes, FN=96. ForA. s. yamashinai the G- and C-banding pattern are presented.Acknowledgment. The authors are grateful to Dr P. T. Tseng, and Mr H. M. Lin of Taiwan Provincial Institute of Infectious Diseases and to Prof. I. Sawada of Nara University of Education for their help during the collection of the material and their encouragement.  相似文献   

10.
Summary The chromosomal sets of five species ofPerlodidæ (Plecoptera) are given in the present paper. The sexual chromosomes belong to three distinct types:X-O,X 1-X 2,X 1-X 2-X 3. The author shows that these three types are likely derived from the most primitive patternX-Y, by translocation and inversion.  相似文献   

11.
Zusammenfassung Die Reaktion von Perchloryl Fluorid (PF) mit Anionen wurde untersucht. Eine leichte Difluorierung fand statt mit Carbanionen vom Typus CH (C=X)2. Mechanismen für die verschiedenen Heterolysen von PF werden vorgeschlagen.  相似文献   

12.
Zusammenfassung Über Chromosomenzahl und Mechanismus der Geschlechtschromosomen von 13 Arten (8 Unterfamilien) indischer Mantiden wird berichtet. Die GattungenHumbertiella, Didymocorypha, Novo Genus der Gruppe Gonypetae vic.Cimantis-Eumantis, Parathespis, Creobroter, Empusa und die ArtDeiphobe brunneri zeigen im Geschlecht dasXO-System.Hierodula coarctata, Cheddikulama straminea undDeiphobe indica zeigen 2n=27 undX 1 X 2 Y.

I am deeply grateful to Prof. G. P.Sharma for his able guidance, laboratory facilities and kind permission to accompany the zoological trip of the department to Rameshwaram Island, for the collection of mantids.  相似文献   

13.
Summary Calathus ascendens (Caraboidea, Pterostichiae, Sphodrini) has 2n=20, XY1Y2: XX. This multiple sexchromosome system seems to be derived from a neo-XY one through an X-autosome fusion.Thanks go to A. Machado for collecting some specimens from Last Lagunets. This work has been supported by a postdoctoral fellowship of the C.S.I.C.  相似文献   

14.
Summary Bordetella pertussis has been shown to remain viable for a period of 13 years on freeze-drying. The revived cultures had unaltered antigenic composition and biological activity.Thanks are due to Dr M. Balasubrahmanyan for his guidance and Dr M.S. Zakharova, Gamaleya Institute of Microbiology and Epidemiology, Moscow, USSR for supplyingB. pertussis factor sera. We thank Mr Ram Jas for his technical assistance.  相似文献   

15.
Zusammenfassung Autoradiographisch wurde die späte DNS-Synthese derX- undY-Chromosomen vonDidelphis virginiana (Virginia Opossum) in Knochenmarkzellen untersucht. Die weiblichen Tiere zeigen typische späte Reduplikationsmuster in einemX, die männlichen das späte Reduplikationsmuster inX undY und inY allein.

This study was supported in part by research grant No. AM-02504 and training grant No. Tl-AM-5277, National Institutes of Health. Dr.Reiss was a predoctoral trainee, National Institute of Arthritis and Metabolic Diseases, U.S. Public Health Service.  相似文献   

16.
Summary The C-banding technique has revealed the existence of single and double intrachromatidic bands in mitotic chromosomes ofTriturus marmoratus. The presence of the bands is discussed on the basis of the helical coil model versus the radial loop model, which assumes a different packing of the DNA fiber.We are very indebted to Prof. C. García de la Vega for his indispensable help, to Prof. Dr J. Martín for his comments and to M. Herrero for his support.  相似文献   

17.
Zusammenfassung Die Synthese eines Analogen des Deamino-oxytocins, in dem ein Schwefelatom der Disulfidbrücke durch eine Methylengruppe ersetzt ist (I,X = CH2,R=H), wird beschrieben. Die Verbindung hat oxytocinähnliche biologische Wirkungen.  相似文献   

18.
Summary A new lignan attenuol has been isolated from the bark ofKnema attenuata (Wall.) Warb. Its structure (I) is deduced on the basis of analytical and spectral data. The compound has been assigned the absolute configuration as 2S,3R-dimethyl-1S-(p-hydroxyphenyl)-6,7-methylenedioxytetralin (III).Contribution No. 487 from the Ciba-Geigy Research Centre.Acknowledgments. We thank Dr H. Fuhrer and Dr P. Moser of Ciba-Geigy Ltd. Basle for the NMR spectral data and ORD determinations and Dr S. Selvavinayakam and his colleagues for the analytical results.  相似文献   

19.
Summary Studies of extracts ofDelphinium seeds, long known to be insecticidal, revealed that a principal insecticidal toxin was methyllycaconitine, which is shown to be a potent inhibitor of -bungarotoxin binding to housefly heads (Kinh=2.5×10–10±0.5×10–10M).Calgary for gifts of MLA, citrate and lycoctonine, and Dr W. Bowers of the University of Arizona for the original extract ofDelphinium seeds. We would also like to acknowledge the able technical support of Ms C. Dushin, Mr E.L. Bowman, Dr C. C. Gagne, Mr R. F. Borysewicz and Dr P. Mowery for his assistance in obtaining and interpreting the carbon-13 NMR spectra.  相似文献   

20.
Summary In infected rats, survival was directly proportional to the metabolic cost of fever (O2%°C) during its rising phase and inversely proportional to the height of fever. It is suggested that some febrile, metabolic response may be beneficial, while the rise in temperature may be harmful for the host animal.I thank Dr W. Mannheim from the Institute of Hygiene for kindly furnishing the cultures ofS. enteritidis. This work was supported by the Schwerpunktprogramm Temperaturregulation und-adaptation of the DFG.  相似文献   

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