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1.
J K Gupta  A Kumar 《Experientia》1979,35(10):1391-1392
Sterility in males and females was observed in the resulting adults when 3--4-day-old pupae of solanaceous hadda, Epilachna vigintioctopunctata F. were exposed to gamma radiation doses of 2000 rad and 2500 rad. However, at 2500 rad longevity of treated insects was adversely affected.  相似文献   

2.
Epidermal sensitivity to hypoxia in the lugworm   总被引:1,自引:0,他引:1  
Summary Physiological and anatomical data support the idea that in the caudal epidermis of the lugworm,Arenicola marina (L.), there are chemoreceptors detecting variations of oxygen partial pressure in the ambient water.This research was partly supported by a C.N.R.S. grant, AI No. 582 085. We thank Dr P. Dejours and Dr J. Taxi for helpful comments and discussion, Mrs S. Dejours for editing the English of this paper, M.F. Baucher, A. Dorme, F. Kleinbauer, the staff of the Station Biologique de Roscoff and the Service de Microscopie Electronique, C.N.R.S., boulevard Raspail, Paris, for technical assistance.  相似文献   

3.
Summary The chloride electrochemical potential difference between the inside of cells ofNitella translucens and some external solutions, where Cl has been progressively replaced by benzenesulphonate, has been measured by means of Ag-AgCl electrodes. It appears that benzenesulphonate moves into the cell by an electrogenic pump and that the uptake of Cl byNitella is not in contradiction with a carrier hypothesis.

This work was supported by grants from the F.N.R.S. and was carried out in the Biophysics Section of the Edinburgh University. We are indebted to Dr. E. J.Williams and Dr.Hogg for having sponsored this research and kindly provided the material.  相似文献   

4.
Summary 2 species of miceMus musculus brevirostris andMus spretus are sympatric in Southern France and reproductively isolated. However, under laboratory conditions, they breed and give fully viable F1 hybrids. This indicates that premating isolating mechanisms probably occur in nature and have yet to be investigated. Moreover, it now enables us to introduce new genetical markers in laboratory strains.

Remerciements. Cette étude a été menée à bien avec l'assistance technique de J. Catalan. Nous remercions également N. Pasteur, J. Britton-Davidian ainsi que tous les membres du laboratoire pour leurs commentaires avisés dans la discussion des résultats. Ce travail est supporté financièrement par l'Université de Montpellier II, l'EPHE et le C.N.R.S. (ERA-261 et ATP-souris).  相似文献   

5.
Summary The rate of tryptophan hydroxylation in vivo is unaltered in brain areas of 5, 9 and 21 week-old Lyon genetically Hypertensive (LH) rats as compared to both Lyon Normotensive (LN) and Low Blood Pressure (LL) rats, except for a decrease in the C1 area of the medulla oblongata in 9 week-old animals.Acknowledgment. The authors wish to thank Dr M.F. Belin, Dr J.F. Pujol and Mrs J. Sacquet for their help during this study. This work was supported by the Fondation pour la Recherche Médicale Française and the C.N.R.S.  相似文献   

6.
Summary Wood frogs survive extracellular freezing at moderate subzero temperatures (–4°C) for at least 11 days. Freezing survival is aided by the accumulation of high concentrations of glucose as a cryoprotectant in blood and tissues. Glucose production was accompanied by a rapid decline in liver, but not muscle, glycogen levels suggesting that liver is the organ controlling cryoprotectant synthesis.Acknowledgments. This study was supported by grants to L.M.G. from the Kroc Foundation (Santa Ynez, California) and from the National Institute of Dental Research (Grant No. DE-03987). The authors wish to thank K. Yorko, M. Shakin, J. Finan and Mrs N. Manivannan for their technical and secretarial assistance.Acknowledgments. I thank Dr J. Ballantyne, Dr F. Schueler and I. McMurray for help with frog collections and Dr. W. Schmid, Dr J. Bogart and Dr F. Cook for helpful discussions. Supported by an N.S.E.R.C. operating grant and by a grant from the Atkinson Charitable Foundation.  相似文献   

7.
Summary Thirteen cows maintained on natural bracken fern (Pteridium aquilinum) were analyzed cytogenetically. The frequency of structural chromosome aberrations detected in peripheral blood cells was significantly higher when compared to that detected in animals raised on pasture containing no bracken fern. We discuss the clastogenic action of fern and its synergistic action with infection by type 2 and 4 papilloma virus in the same animals.Acknowledgments. We are grateful to Dr F. J. Benesi, Dr J. L. Guerra and Dr I. L. Sinhorini for performing some of the clinical and pathological analyses; O. P. Ferraz, L. A. Tadeu Dias, L. F. Feitosa and A. M. N. Paiva for technical assistance; and to Dr N. H. C. Castro and Dr C. de Araujo Peres for critical and statistics review, respectively. Research was supported by CNPq FAPESP and CAPES.  相似文献   

8.
Summary Seeds ofZornia diphylla possess a complex type of dormancy which is of great survival value for the species. Seeds show polymorphism. The optimum temperature for germination explains the cause of its distribution in the tropics. The grazing and scraping promotes the vegetative growth.The author is grateful to Dr.R. Sahai and Dr.R. S. Tripathi, Gorakhpur University, for guidance and to Dr.Y. B. Singh, Principal, and Dr.G. C. Srivastava, Head Dept. Botany, for encouragement and facilities. Thanks are due to my colleagues late SriP. N. Gupta, SriJ. Abraham, SriF. Abbasi, and Dr.A. B. Sinha for their cooperation.  相似文献   

9.
Summary Hydrostatic pressure applied to isolated eel gills induces changes in the tissue, Na+, K+ and Cl contents. It also inhibits the activity of the (Na++K+) ATPase. Results are discussed in terms of an effect of pressure on the Na+ and Cl pumps and on the passive permeability processes.A. P., Chargé de Recherches du F. N. R. S.; R. G., Chercheur qualifié du F. N. R. S., We are grateful to Prof. A. Distèche and E. Schoffeniels for their advice throughout this work. We also want to thank Mr J. M. Theate and Mrs C. Marchand-Coquay for their valuable technical assistance.  相似文献   

10.
Zusammenfassung BeiP. maculatus werdenXY-Embryonen durch Röntgenstrahlenbehandlung (1000 bis 2500 R) physiologisch zu normalen Weibchen umdeterminiert.  相似文献   

11.
Summary The attraction ofS. scolytus to the components of Multilure is described. 4-Methyl-3-heptanol is an attractant which is synergised bya-cubebene. Multistriatin appears to be an inhibitor. A combination of 4-methyl-3-heptanol and cubeb oil is more effective as a bait forS. scolytus than Multilure.We thank Mr A. K. Hughes and Mr J. Boswell for their cooperation in allowing us to conduct experiments on Parham Estate; Mr D. Mobbs and Mr C. Thorne for the statistical analyses; Dr J. W. Peacock for samples of mixed isomers of multistriatin and distilled cubeb oil; Mrs J. Allsop and Mr N. J. Fielding for technical assistance. We are grateful to Mr D. Bevan, Dr J. H. Borden, Dr J. F. Grove and Prof. A. W. Johnson for their interest and encouragement.  相似文献   

12.
Zusammenfassung Aus Arbeiterinnen der AmeiseMonomorium pharaonis (L.) wurde 5-Methyl-3-butyl-octahydroindolizin isoliert. Dieses Pheromon übt eine starke Lockstoffwirkung auf die Arbeiterinnen dieser Ameisenart aus. Die Struktur wurde durch Spektral-analyse und Synthese aufgeklärt. Unseres Wissens ist dies das erste Pheromon aus Insekten mit dem Indolizingerüst.

Acknowledgment. This work was supported by the Ministry of Health and Environmental Hygiene of the Netherlands. Pharaoh's ants were supplied by Dr.A. Buschinger, Bonn, and Mr.W. R. C. M. van der Loo, Rotterdam. The spectroscopical work was done by a team includingR. Deen, P. J. F. Nooijen andS. J. Spijk andJ. M. Timmner assisted in the synthesis.  相似文献   

13.
Fluorinated analogs of insect sex pheromones   总被引:1,自引:0,他引:1  
Summary The syntheses of fluorinated mimics of pheromones ofSpodoptera littoralis, Diparopsis castanea, Laspeyresia pomonella, Bombyx mori andThaumetopoea pityocampa are described. These analogs showed biological activities similar to those of the natural pheromones in laboratory assays (EAG).We gratefully acknowledge Comisión Asesora de Investigación Cientifica y Técnica for financial support (Grant No. 3296/79) and Consejo Superior de Investigaciones Cientificas for predoctoral and postdoctoral fellowship (to G.F. and M.R.). We also thank Mr J. Baltá and Ms R. Murgó for their collaboration in the EAG work.  相似文献   

14.
Summary A mutation conferring increased antibiotic resistance onSalmonella typhimurium strain 11G carrying R124 was plasmid determined; strains harbouring the mutant plasmid contained more DNA as ccc plasmid than those harbouring R124. The increased copy number was manifested at all growth rates at all growth rates tested.This work was supported by a grant (to R. J. R.) from the Central Research Fund of the University of London and by a studentship (to J. J. P.) from the Science Research Council.  相似文献   

15.
Summary Exposure of frog neuromuscular junctions to heat-killed, lyophilizedSalmonella typhimurium (SR 11) produces an early increase in spontaneous transmitter release followed by depression of release and blockade of the obligatory release usually induced by ionophore X537A.This study was supported by the Office of Naval Research, Biophysics Section, NR 202-160, N00014-77-C-0630. X537A was a gift of Hoffman-LaRoche. I am greatly indebted to Dr R. McCallum for preparing the Salmonella material. J.A. Kuhn provided the technical assistance.  相似文献   

16.
Summary The peroxidase patterns ofNicotiana suaveolens, N. glutinosa and their interspecific hybrid have been studied, and their possible genetic control analyzed. Modifications of the isozymatic pattern along the plant have been observed.Acknowledgments. The authors thank Prof. J.R. Lacadena and Dr M. Pérez de la Vega for their valuable advice.  相似文献   

17.
Summary Aggregated oviposition byChymomyza amoena in Virginia and Michigan has been shown to be due to egg clustering, females attracted to fruits on whichC. amoena females have already oviposited, and to variation in fruit attractiveness. Negative binomialk values support behavioral similarities among females of this rarely seen species in both states. Discovery ofC. amoena in Europe may indicate that this larval overwintering drosophilid has a Holarctic distribution.The research in Virginia during summer 1986, conducted at Mt. Lake Biological Station, was supported by a fellowship from the University of Virginia. Thanks are gratefully extended to all property owners in Virginia and Michigan for allowing me to collect fruits and to Blaine Cole, Director and J.J. Murray, Chairman of the Biology Dept., University of Virginia for research space in 1986 and 1987. R. N. Band constructed the figures. Comments from reviewers have been helpful.  相似文献   

18.
Summary The survival time of adultDrosophila melanogaster flies without food is greater in the presence of ethanol, especially for flies of strains or lines with a higher alcohol dehydrogenase activity. It seems that theebony gene can act in some populations as a selective factor favoring the ADHF allele, as well as the minor genes enhancing the alcohol dehydrogenase activity level.Chargé de Recherches au F. N. R. S.  相似文献   

19.
Summary First variation at theLdh-A locus and a new allele at theLdh-B locus are reported in aM. musculus population dimorphic at theLdh-A locus and in aM. spretus population trimorphic at theLdh-B locus.Acknowledgments. This study was achieved with the technical assistance of J. Catalan. We thank N. Pasteur and F. Bonhomme for useful comments. This work was supported by the Université Montpellier 2 (service électrophorèse du Centre de Recherche sur l'Evolution et ses Mécanismes), the Ecole Pratique des Hautes Etudes and the Centre National de la Recherche Scientifique (ERA 261).  相似文献   

20.
Summary The compound, 3,5-dibromo-2-chloro-4-isothiocyanatosalicylanilide, has been tested against various nematode and cestode parasites in experimental and domestric animals. It shoved 100% activity againstAncylostoma ceylanicum, A. tubaeformis, Syphacia obvelata, Ascaridia galli, Toxocara spp.,Toxascaris sp.,Gnathostoma spinigerum, Hymenolepis nana, Raillietina spp. andTaenia spp. in doses 25–70 mg/kg given in single or multiple administrations.Acknowledgments. We express sincere thanks to Dr Nitya Nand, F.N.A., CDRI, Lucknow, for his keen interest in the work, to Dr B. N. Dhawan, F.N.A. for providing informations about general pharmacology of the compound, and to Dr R. K. Chatterjee and Dr P. K. Murthy for carrying out antifilarial sreening. Technical assistance of Mr S. C. Bhar and Mr S. Ram is acknowledged.  相似文献   

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