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1.
Summary 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.Acknowledgment. Financial help to one of us (J.K.G.) by C.S.I.R. in the form of J.R.F. is gratefully acknowledged. Authors are thankful to Prof. P.N. Srivastava and Dr A.R. Rao, School of Life Sciences, J.N.U. Delhi for providing radiation facility.  相似文献   

2.
Summary Pressmud, a sugar factory waste, was fermented with methanogenic bacteria in an anaerobic fermenter for 40 days at 31±2°C. The pressmud residue obtained after fermentation was used as a source for the extraction of phytosterols. The anaerobic digestion degraded the organic matter and resulted in enrichment of phytosterols from 0.33% in the pressmud to 3.05% in the residue. Refluxing of 100 g of residue with benzene, petroleum ether, and ethanolic KOH (1051) yielded 8 g of soft cake, which on further fractionation with methylcyanide and isopropanol gave three fractions: 1) a crude mixture of phytosterols, 2) resin, and 3) undigested organic matter. The crude mixture of phytosterols after purification on neutral alumina followed by GLC analysis resulted in the separation of 68.7% of -sitosterol, 18.4% of stigmasterol and 12.9% of campesterol and brassicasterol together. Phytosterols were extracted more easily from fermented than from unfermented samples, because of biodegration of lipophilic compounds by the methanogenic bacteria.Acknowledgments. S.K.S. and J.C.S. are thankful to the authorities of the U.G.C., New Delhi, for the award of Teacher-fellowships. R.C.S., R.A.K.S. and D.K.M. are thankful to the authorities of the C.S.I.R., New Delhi, for providing R.A., S.R.F., and J.R.F., respectively. Reprint request to S.N.M.  相似文献   

3.
Summary InPennisetum typhoides S. and H., a new karyotype was found with 13 normal chromosomes and 2 stable telocentric chromosomes, which represent 1 arm each of a submetacentric chromosome.The authors are thankful to Dr.J. V. Pantulu, Professor of Cytogenetics, for guidance and encouragement and to Dr.V. Manga, for helpful discussion. They express their thanks to the U. G. C. (PSRLNR) and to the C. S. I. R. (MVSR and INR) for the award of Junior Research Fellowships.  相似文献   

4.
Summary Crude leaf extracts of 17 plants were tested for their antiviral activity against BCMV. An extract ofAzadirachta indica A. Juss. was found to be most potent in reducing the infectivity of the virus.Authors are thankful to Dr R. D. Joshi for his valuable guidance and Prof. S. N. Mathur for providing lab facilities. Financial assistance by U. G. C. and C. S. I. R. is gratefully acknowledged.  相似文献   

5.
Summary We describe a new rapid and simple method for collection and preparation of cell suspensions for electron microscopy; the cells are prefixed with glutaraldehyde in their culture medium, and are then compacted on a filter disc. Post-fixation in osmium, staining and dehydration are performed by transferring the filter disc and the cell pellet from one solution to the next. The pellet is easily separated from the filter disc just before treatment in propylene oxide. This method preserves the fine structure as well as the classical technique. Advantages are that numerous cells have the same orientation in the sections and that many samples can be taken in a very short time.Acknowledgments. The authors are indebted to Prof. H. Leclerc, Director of I.N.S.E.R.M. laboratory U 146 in which part of this work has been performed, and to Dr J.F. Dubremetz, Dr G. Prensier and Dr P.A. Trinel for their advices.  相似文献   

6.
Summary Ornithine aminotransferase (E.C. 2.6.1.13) from rat brain was purified 100-fold by ammonium sulphate fractionation, DEAE cellulose chromatography, calcium phosphate gel and alumina C gel. Pyridoxal phosphate was essential for maximum activity of the enzyme. The brain enzyme did not differ from liver and kidney enzymes in properties such as pH optimum, Km, substrate specificity and the inhibition by branched chain amino acids. Unlike rat liver enzyme, brain ornithine aminotransferase was able to catalyze the reaction between L-lysine and 2-oxoglutarate. Spermidine and spermine inhibited brain ornithine aminotransferase activity.Acknowledgments. D.R.D. is thankful to U.G.C., India, for the award of a fellowship under the special assistance programme. Present address: Department of Pediatrics and Communicable Diseases, F2815, Box 066, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI 48109, USA.  相似文献   

7.
Summary Neurosecretory substance has been identified in the rostral process of bipolar neurosecretory cells of the caudal neurosecretory system in 4 Indian catfishes, using acid violet stain. The role of the rostral process in the transmission of the neurosecretory substance is discussed.We thank Prof. U.S. Srivastava, Allahabad University, for laboratory facilities and useful suggestions. The U.G.C. financial assistance under the Faculty Improvement Programme, to one of us (H.C.S.) is gratefully acknowledged.  相似文献   

8.
Summary The outer densely calcified layer of the alligator eggshell shows progressive crystal dissolution, with the production of concentrically stepped erosion craters, as incubation progresses. This dissolution is caused by the acidic metabolic byproducts of nest bacteria. Extrinsic degradation serves to gradually increase the porosity and decrease the strength of the eggshell.The work is supported by M.R.C. grant No. G979/386/CB and E.H.S.S.B. grant No. EB 109/74/75.  相似文献   

9.
Summary The females ofDrosophila bipectinata andD. malerkotliana are able to discriminate between their own and alien males in the absence of antennae. Thus mate recognition seems to depend on contact chemoreceptors in these 2 species.We are grateful to the Head of the Department of Zoology, B.H.U. for providing the necessary facilities. Thanks are due to the U.G.C., New Delhi, India for awarding a junior research fellowship to O.P.S.  相似文献   

10.
Summary Impaired breeding performance of aged female mice was associated with reduced numbers of ovulations and increased mortality of embryos. The amounts of progesterone in the sera, corpora lutea and uterine flushings of these animals were similar to those of young animals when measured by radioimmunoassay.Financial support was provided by the Medical Research Council (R.G.G.) and the Ford Foundation and one of us (R.E.F.) wishes to thank Lucy Cavendish College, Cambridge, for their support with a Calouste Gulbenkian Research Fellowship.  相似文献   

11.
Summary In the human leukemia K-562(S6) cell line (a) the accumulation ofa-globin chains is low or absent, (b) -globin gene expression is correlated with expression of -chains and (c) the genes responsible for the terminal cell division are not operated within 8–12 cell cycles, while K-562 (S6) cells are fully induced to erythroid differentiation.This work was supported by grants from the Italian National Research Council (C.N.R.) G. R. is a recipient of a fellowship from the National Committee for Nuclear Energy, Rome. Address for reprint requests: R. G., Centro di Studi Biochimici, Via L. Borsari 46, I-44100 Ferrara.  相似文献   

12.
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   

13.
By means of indirect immunofluorescence with sera obtained from patients after bone marrow transplantation it has been demonstrated that antibodies were reacting with the cytoplasm of basal cells ((C.B.C.) in the external root sheath of hairs (E.R.S.). Some sera were found to react with C.B.C. of the E.R.S. but not with the C.B.C of the epidermis. The change in the antigenic properties of the basal cells was found to be situated at the orifice of the sebaceous gland duct.  相似文献   

14.
Summary Two distinct polypeptides have been isolated from rat heart and ox blood. They are both found to be effective in forming complexes with sodium ions, and it is suggested that they may have a function in stabilizing sodium ion activity.Acknowledgments. We are indebted to ProfessorG. A. Gilbert, F.R.S. and to Dr.C. J. Lote for helpful discussion, and to the Royal Society for a Grant-in-aid which in part supported the investigation.  相似文献   

15.
Phenylethanolamine, p-octopamine and m-octopamine contents were determined in the hypothalamus and the brain stem of spontaneously hypertensive Rats (S.H.R. Kyto) and the corresponding controls (Wistar Kyoto). In three-week-old Rats, phenylethanolamine and p-octopamine are found to be present in S.H.R. hypothalamus and brain stem at concentrations twice as high as compared to Wistar Kyoto Rats. The amount of m-octopamine is 5-fold higher in the brain stem of S.H.R. Rats as compared to Wistar Kyoto Rats.  相似文献   

16.
Summary Electrical responses of the retinas of 4 species of microchiropteran bats stimulated by spectrally restricted light flashes were found to diverge systematically from the rhodopsin absorption spectrum. The divergence was progressively greater across the 4 species. The results appeared explainable by assuming a second photoreceptor class and photopigment which was present in progressively greater numbers in the retinas ofEptesicus fuscus, Desmodus rotundus, Artibeus jamaicensis andCarollia perspicillata.This work was made possible by equipment provided by grant No. EY 01228 from the U.S.P.H.S., Bob Hope Fight for Sight award No. G 522 and a grant from Research to Prevent Blindness, Inc. Portions of this work were presented at the Fifth International Bat Research Conference, Albuquerque, New Mexico, August 11, 1978.The authors would like to express appreciation to Drs A.M. Potts, J. B. Longley, R. S. Crockett and T. G. Wheeler for helpful suggestions and to Drs J. H. Richardson, J. G. Cooper, L. Kundrotas, Mr B. Spoonamore and Mr W. Lopez-Forment for facilitating collection and importation of the Mexican bats.  相似文献   

17.
Summary It is shown that the Australian lungfish (Neoceratodus forsteri) synthesizes ascorbic acid in its kidney, suggesting that ascorbic acid synthesis started before the origin of the tetrapods.Acknowledgments. We would like to thank Dr G.C. Grigg, University of Sydney, Mr R. B. Humphries, Dr P.A. Janssens and Dr C.H. Tyndale-Biscoe, Australian National University, and Dr. M. Griffiths and J.C. MacIlroy C.S.I.R.O., Division of Wildlife Research for supplying the tissue.  相似文献   

18.
Summary The infective forms of Nuttallia, meri, a small-mammal piroplasm, first appear as spindle-shaped sporozoites in and around the salivary glands of Ornithodoros erraticus (small race) 30 days after the ticks had fed on infected blood. O. erraticus is the only soft tick so far proved to transmit a piroplasm.I thank Miss Zipora Goldberg for meticulous technical help, Mrs H. Salomon for the photomicrographs, and Dr. Y. Schlein and Prof. P. C. C. Garnham, F. R. S. for advice and comments.  相似文献   

19.
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   

20.
Summary Cornea regeneration in a Pacific giant octopus,Octopus dofleini, occurred within 10 days after the injury was observed. Surgical removal of the cornea in 2 common octopi,O. vulgaris experimentally duplicated this cornea regeneration within a 10-day period. It is, therefore, concluded that besides sucking discs, arms, and nerve fibres, octopi can also regenerated corneal tissue.The authors would like to thank U. E. Friese, B. Borowski, P. Burn, J.W. Atz, G.J. Nelson, H. Feinberg, P. Fenimore, C. Roper, M. Nixon, M. Segalla, G. Clark, D.O. Calligaro, J.M. Anderson and R.J. Koestler for assistance and advice. Illustrations were drawn by G.D. This work was supported by the New York Aquarium of the New York Zoological Society, while G.D. was at the New York Aquarium.  相似文献   

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