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1.
Summary In the female Indian frog,Rana tigrina (2n=26; NF=52), the female is heterogametic. The heterochromosomes (ZW) are morphologically indistinguishable, but the W chromosome proves by C-banding analysis to be entierly heterochromatic.Acknowledgment. S.C. is grateful to Prof. G.K. Manna, Zoology Department, Kalyani University, Prof. Archana Sharma, Botany Department, Calcutta University and to Prof. T. Sharma, Zoology Department, Banarus Hindu University for encouragements. He is also thankful to Prof. D.K. Choudhuri, Burdwan University for support.  相似文献   

2.
Summary An acid-alkaline treatment followed by Coriphosphine-O staining was used for detecting chromosomal differences between the 2 sibling speciesAnopheles atroparvus (van Thiel) andA. labranchiae (Falleroni) (Diptera: Culicidae). The short arm of the Y chromosome was found to stain differently in the 2 species.The authors wish to thank the entomologist C. Contini for collecting and classifyingA. labranchiae larvae and Prof. U. Bianchi and Prof. U. Laudani for helpful discussions and suggestions on the subject.  相似文献   

3.
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   

4.
Summary In 2 species of terrestrial isopods, namelyPorcellio assamensis andP. laevis, the diploid and haploid numbers of chromosomes have been established to be 48 and 24 respectively for the former species and 50 and 25 respectively for the latter species. Female heterogamety of the ZW type has been found to exist inP. laevis.The authors express their sincere thanks to Prof. G.P. Sharma, and to Prof. S. Khera, Department of Zoology, Panjab University, Chandigarh, for the necessary laboratory facilities.  相似文献   

5.
Summary The gynogenetic offspring of the hybrid frogRana esculenta (R. ridibunda x R. lessonae) are exclusively of theridibunda type. This is due to the premeiotic exclusion of thelessonae genome from the hybrid's germ cells.Acknowledgments. Prof. M. Fischberg, Genève, and Prof. P. Vogel, Lausanne, provided laboratory facilities. This research was supported by the Swiss National Science Foundation, grants 3.221-0.73 and 3.644-0.75.  相似文献   

6.
Summary The karyotype of a cyprinid fish occurring in India,Tor putitora is described. The diploid complement comprises 100 chromosomes. The modal number in this family being 2n=50,T. putitora appears to be another case of tetraploidy.The author is highly indebted to Prof. G.K. Manna, and Prof. A.K. Bose, Department of Zoology, University of Kalyani, for encouragement and laboratory facilities. Sincere thanks are due to Dr Raj Tilak, ZSI, Government of India, for identification of the specimens. Financial aid from the University of Kalyani is gratefully acknowledged.  相似文献   

7.
Summary The fine structure of the sieve element plastids ofBambusa vulgaris andSchizostachyum lumampao revealed the typical monocotyledonous type (P-type) with the cuneate proteinaceous bodies and lattice-like crystalloids; in addition, characteristically formed vesicles and tubulae could be observed. The diagnostic value of these plastids is also discussed.Thanks are due to Prof. W. Liese, Hamburg, and Dr K. Dunkelberg, Munich, for collecting the material, and to Prof. H.-D. Behnke, Heidelberg, for critical perusal of this note. Technical assistance of Mrs R. Schultze is also acknowledged.  相似文献   

8.
Summary Free ecdysteroids were extracted from intermolt and premolt larvae ofLimulus polyphemus in the first posthatch stage, purified by TLC and HRLC, and assayed by RIA and theLimulus bioassay 20-hydroxyecdysone appears to be a principal ecdysteroid and occurs at least 3 times higher a concentration in premolt vs intermolt animals.Supported by NSF grant GB-40620.Acknowledgments. We are indebted to Prof. G. R. Wyatt for the antibody, Prof. K. Nakanishi for use of his laboratory for HRLC separations, and to Dr David King for the3H-ecdysone and for performing radio-TLC analyses.  相似文献   

9.
Summary The chromosomes of 2 Italian populations ofReticulitermes lucifugus (Rossi) were studied in both spermatogonial and oogonial divisions. The diploid chromosome complement is 2=42. All the first meiotic metaphases in Sardinian males show a complex translocation arranged in chains of 4 bivalents. The Apulian males show either 21 bivalents or 19 bivalents and a chain of 2.The authors express their thanks to Prof. A. Springhetti for his kind help in supplying the materials and for criticism in preparation of this paper, and to Prof. G. Colombo for valuable advice and criticism.  相似文献   

10.
Summary A net absorption of glycine, L-alanine and L-phenylalanine occurs across the isolated midgut of the larvae ofBombyx mori. Although glycine and L-phenylalanine are not metabolized, L-alanine is converted by the midgut and has a metabolic effect on the transepithelial electrical potential difference of the tissue.Acknowledgments. We are very much indebted to Prof. V. Capraro for helpful advice and criticism. We are also grateful to Prof. G. Reali for his interest and support of this research.  相似文献   

11.
Summary The first isolation of (+)-abscisic acid from a fungus,Cercospora rosicola, is reported.Acknowledgments. The authors wish to express appreciation to Prof. Romano Locci for helpful discussions.  相似文献   

12.
Summary Glycozoline and girinimbine isomers (IV andVII) were synthesized and their activity against 2 bacterial strains, viz.E. coli andS. aureus, and 2 fungal strains, viz.C. albicans andA. niger were studied. The hydroxy synthons (III) were also tested. The authors are thankful to Dr B.N. Apte, Association of Microbiologists of India, Bombay Unit, for providing some of the organisms, to Prof. A.K. De, Indian Institute of Technology, for financial assistance, to Prof. G. D. Shah, Department of Chemistry, Indian Institute of Technology for guidance, encouragement and helpful discussions.  相似文献   

13.
Summary Drosophila hydei larvae homozygous for the gene1(3)gl may survive to the age of 3 weeks, become bloated and be incapable of metamorphosis. Wild-type flies after the injection of a fragment of the1(3)gl disc, which has been previously culture in vivo for 40–500 days, also become bloated (ascitic reaction). In the hemolymph of both the advanced1(3)gl larvae and ascitic adult hosts the accumulation of a specific protein is observed.Acknowledgments. This work was supported by the Swiss National Science Foundation under Grant No.3.792-0.76 and the Georges und Antoine Claraz-Schenkung. We thank Prof. H. Gloor, University of Geneva, and Prof. P.S. Chen, University of Zürich, for advice and criticism.  相似文献   

14.
Summary The karyotypes ofTor khudree andTor tor, occurring in the Himalayan streams in India, are described. As reported earlier forT. putitora, the diploid complements in these 2 congeneric species also comprise 100 chromosomes. The modal number being 2n=50 in this family,Tor appears to be of tetraploid origin.The author is greatly indebted to Prof. G.K. Manna, and Prof. A.K. Bose, Department of Zoology, University of Kalyani, for encouragements and laboratory facilities. Financial aid from the University of Kalyani is gratefully acknowledged. Sincere thanks are also due to Dr M.K. Jyoti and Miss Anu Agarwal of the Department of Biosciences, Jammu University for their cordiality and help in various ways during my stay at Jammu.  相似文献   

15.
Summary BuffaloaS1-casein was treated with carboxypeptidase-A to determine the C-terminal amino acid residue, which was — leucine-tryptophan. The Sakaguchi reagent was used to confirm arginine as the N-terminal amino acid. The colored p-phenylazophenyl thiohydantions of tryptophan and arginine released from C- and N-terminals respectively were quantitatively estimated and from this molecular weights of buffaloaS1 casein were calculated and found to be 26,300 and 26,100 respectively.Acknowledgment. We are thankful to Prof. B. K. Bachhawat, Indian Institute of Chemical Biology, for encouragement. We also thank Prof. S. K. Mukherjee, Bose Institute, for amino acid analysis. Part of this work was completed when the authors were at the University of Kalyani, West Bengal.  相似文献   

16.
Summary The C-band on the chromosomes of the Japanese house shrew,Suncus murinus riukiuanus (Insectivora), was studied. Various types of C-banding pattern were found in the genome of this subspecies. Such banding patterns could be useful for an understanding of autosome and sex-chromosome polymorphisms withinS. murinus.Acknowledgment. The authors are very grateful to Prof. T. Wasano of Fukuoka University for his encouragement, Dr K. Ogawa of Fukuoka University, the Nohara family for help in collecting specimens, and Prof. E.W. Jameson, Jr, University of California, Dr J.W. Bickham and his students of Texas A & M University for comments.  相似文献   

17.
Summary Drosophila melanogaster adults were collected for several years in various localities of Italy. The frequencies of thePgm electrophoretic alleles were determined and the similarity of the configuration of allelic frequencies observed. It was concluded that the PGM electrophoretic polymorphism could be maintained by random genetic drift in the natural populations studied only if the effective breeding size (N e ) during the bottle-neck period is about 5000.I am grateful to Prof. D. Sperlich and Prof. W. Seyffert for their kind hospitality during my sojourn as Research Fellow of the Alexander von Humboldt Foundation in the Institute of Biology II at the University of Tübingen (FRG) where the final version of this paper has been done. The technical assistance of Mr A. Micheli is also acknowledged.  相似文献   

18.
Summary The peptide map obtained by electrophoresis after digestion of purified myosin heavy chains from pectoralis muscle of embryonic chicken with theStaphylococcus aureus V8 protease, produces a peptide pattern very similar but not identical to that of adult fast myosin. In fact, some components that are present in a small amount in the map of slow adult myosin are visible in the embryonic pattern.Acknowledgments. I wish to acknowledge the enthusiastic encouragement of Dr Ugo Carraro and the help of Prof. Stefano Schiaffino's group and of Dr Marcello Cantini for embryonic tissue isolation. The skillful technical assistance of Mr Silvio Belluco is also gratefully acknowledged. This work was supported in part by a grant of Muscular Dystrophy Association of America to Prof. Massimiliano Aloisi.  相似文献   

19.
Summary Giffordene, 2Z, 4Z, 6E, 8Z-undecatetraene, and five stereoisomers are new odoriferous C11H16-hydrocarbons from the marine brown algaGiffordia mitchellae. Their isolation and identification is described.Acknowledgments. We thank Prof. G. Ohloff for kindly providing us with synthetic 1,3,5,7-undecatetraenes and Prof. P. Schreier for GC/FTIR-analyses.  相似文献   

20.
Summary The fatty acid composition of a new strain of the yeastRhodotorula glutinis, grown in molasses, has been studied and found to contain palmitic, stearic, oleic, linoleic and linolenic acids, and small amounts of other constituents. In addition, 3-methoxy octadecanoic acid has been shown to be present in the glycolipid fraction.Partly presented at the National Symposium on Natural Product Chemistry held on February 7–8, 1983 at Bose Institute, Calcutta (India).Acknowledgments. Authors are indebted to Prof. S.C. Bhattacharyya, and Prof. A.K. Barua, Department of Chemistry for providing facilities for this work.  相似文献   

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