首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Summary A peculiar neurosecretory system is reported in 6 teleost species;Clarias batrachus, Heteropneustes fossilis, Mystus seenghala, Ompak pabda, Glassogobius giuris andNotopterus notopterus. It is located in the gill region close to the pseudobranch or to the carotid labyrinth. The neurosecretory cells have been identified using stains specific for neurosecretion. The results are discussed in the light of the association of the neurosecretory system with the pseudobranch or the carotid labyrinth, and the airbreathing habit of these fishes.We are grateful to Prof. U.S. Srivastava for providing laboratory facilities and for encouragement. The work was financially supported by U.G.C. Research Project grant awarded to C.B.L.S., which is thankfully acknowledged. Thanks are due to M. Seal and Amarlata for technical help rendered.  相似文献   

2.
Summary Histological preparations for light microscopy have revealed for the first time the structure of the electroreceptor ofClarias batrachus andHeteropneustes fossilis, the 2 Indian air-breathing catfishes. These sensory organs are found to resemble the ampullary organs of many weakly electric and nonelectric electroreceptive teleost.The work was in part supported by grant of SCST (U.P.) during the period 1974–76 which is acknowledged.  相似文献   

3.
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   

4.
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   

5.
Summary Among the haemocytes ofSarcophaga ruficornis, only the prohaemocytes divide. Injection of phytohaemagglutinin-P induces 100% prohaemocytes to undergo mitosis but does not induce mitosis in other cells. Mitotic stages other than the prophase are apparently very short lived.Acknowledgment. We express our gratitude to the State Council of Scientific and Industrial Research, U.P. for the grant of financial assistance to U.S.S.  相似文献   

6.
Summary A definite seasonal change is observed in 2 transaminases, SGOT and SGPT ofR. tigrina. Cold acclimation significantly depresses transaminase activity of serum.Acknowledgments. Thanks are due to Dr M.M. Goil and Dr R. K. Sharma for their invaluable help in various ways. Dr K. Singh would also like to thank S.C.S.T., U.P., for the financial assistance.  相似文献   

7.
Summary 8 species of the subtribe Microseridinae contain between 1100 and 3400 genes for 25 and 18 S ribosomal RNA. The gene numbers seem to evolve by discrete steps. Their trend follows a general reduction in genome size during the evolution of the annual species ofMicroseris, but numbers remain high in one of them and inAgoseris grandiflora. 2 species ofPyrrhopappus differ by a duplication of the ribosomal gene numbers; 5 S ribosomal RNA genes in 4 species are repeated roughly 10,000 times.We thank Miss S. Werner, Miss A. Roth and Miss U. Krehan for help with some of the experiments. This paper is part of a project supported by grant Ba 536/1-5 from the Deutsche Forschungsgemeinschaft.  相似文献   

8.
Summary Haemolymph ofPalamnaeus bengalensis contains normally 12 and during moulting up to 15 free amino acids, being in maximal number at the end of ecdysis. Aminoacidaemia is most pronounced during the pharate stage. Tyrosine appeared for tanning of the cuticle. Taurine and methionine were not present.Acknowledgment. The author is thankful to Dr.S. C. Shrivastava for valuable guidance and State C.S.I.R. (U.P.) for funds.  相似文献   

9.
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   

10.
Summary Allantoinase, an enzyme in the purine-urea cycle, was found inEudistylia vancouveri (Polychaeta). The enzyme had a pH optimum at 7.6 TheK m was 0.012M allantoin, and the Arrhenius energy of activation was 12.6 to 14.6 kcal/mol.Supported by the U. S. National Science Foundation (Institutional Grant) and by the U. S. Environmental Protection Agency Grant No. T-900204 (WP-175). Publication No. 10 of the Laboratory of Biochemical Ecology; College of Fisheries Contribution No. 458. We thank Dr.Robert L. Fernald for generously making available to us the facilities of the Friday Harbor Laboratories, Friday Harbor, Washington.  相似文献   

11.
Summary The foot pad polytene chromosome IIIL ofParasarcophaga ruficornis andP. misera shows a heterozygous puff in the region 7B-C. InP. ruficornis the heterozygosity is manifested as a difference in the timing of puffing between the 2 homologues. The outer and inner dorsal cells of the same foot pad also reveal asynchrony in puffing at this locus.Acknowledgments. Thanks are due to Prof. U.S. Srivastava, Head, Dept. of Zoology, University of Allahabad for providing the laboratory facilities.  相似文献   

12.
Summary p-Chloromercuribenzoate inhibited the poly (U)-dependent binding of Phe-tRNA to the 40S ribosomal subunit but displayed no inhibitory effect on the binding of poly (U) to the ribosome. Other sulfhydryl reagents tested, likeN-ethylmaleimide and iodoacetamide, did not affect the binding of Phe-tRNA to the small ribosomal subunit.  相似文献   

13.
Summary The metabolism of the trichothecene 4-monoacetoxyscirpenol by intact gut tissue was determined in the fungus-feeding Nitidulid,Carpophilus hemipterus (L.) and the non-fungus-feeding caterpillars, the fall armyworm,Spodoptera frugiperda (J. E. Smith) and the corn earworm,Heliothis zea (Boddie). The primary metabolite was the hydrolysis product scirpentriol. The amount of metabolism by theC. hemipterus larvae was ca 10 times that of the caterpillars on a per mg protein basis, suggesting metabolic adaptation for feeding on fungi that may contain mycotoxins.Acknowledgment. The authors wish to thank S. Taylor for technical assistance.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   

14.
Summary Autoradiographic studies using3H-uridine in the salivary gland of adultLygaeus sp. were carried out. The gland cell nuclei, particularly the multiple nucleoli, are the sites of incorporation of the label exhibiting RNA synthesis. The labelled molecules (RNA) are transported to the cell cytoplasm and then into the gland lumen in which no turnover of the radioactivity is observed.I am grateful to my teacher, Prof. P. S. Ramamurty, School of Life Sciences, University of Hyderabad, for his constant inspiration. Grateful acknowledgement is made to Prof. J. P. Thapliyal, Dept of Zoology, B. H. U. for encouragement and to Dr Om Prakash, Dept of Biochemistry, B. H. U. for his valuable criticism.  相似文献   

15.
Summary In all the 3 pairs of optic lobes ofCryptophora sp. there are small groups of monopolar PF neurosecretory cells which take on a green colour by PF technique and red by Azan. Their function is unknown, but they may be involved with photoperiodically controlled activity rhythms.We wish to express our thanks to Prof. U.S. Srivastava for providing working facilities and valuable suggestions.  相似文献   

16.
Summary Drosophila melanogaster was unable to dealkylate and convert [14C]sitosterol to cholesterol and no evidence was found for conversion of [14C]desmosterol to cholesterol. Therefore,D. melanogaster is incapable of dealkylating and converting C28 and C29 phytosterols to cholesterol.The authors thank O. J. Duncan III, and H. S. Symonds for technical assistance. Mention of a company name or proprietary product does not imply endorsement by the U.S. Department of Agriculture.  相似文献   

17.
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   

18.
Zusammenfassung Die Form der Mitochondrien und das Verhalten des Mitochondrien-Nukleoids im SchleimpilzPhysarum polycephalum werden durch Behandlung mit Actinomycin C in einer Weise modifiziert, die darauf schliessen lässt, dass die Mitochondrien einen regelmässigen Teilungszyklus durchlaufen, der mit der Teilung des Nukleoids korreliert ist.

Supported by U.S.P.H.S. Grant No. 5-RO-1-GM 11949-04 and by the U.S. Atomic Energy Commission, Contract No. COO-1432-7.  相似文献   

19.
Zusammenfassung Aus den Blättern vonGymnema sylvestre wurden 4 Gymneasäuren (A, B, C und D) isoliert. Die Antivirusaktivität der Säuren A und B wurde geprüft.

This investigation was supported in part by U.S. Army Medical Research contract No. DA-49-193-MD-2066, and by U.S. Public Health Service grants No. AM 06224-04 and AI 05876-03. Presented in part before the 1967 annual meeting of the American Society for Microbiology.  相似文献   

20.
Summary The toxic effects of Temik (aldicarb) on a fresh water Himalyan lake teleost,Barbus conchonius were investigated in hard and soft water. The 48-, 72- and 96-h TLm-values in mg/l were 8.99, 2.39 and 2.42 respectively in the hard-water test and 3.30, 0.62 and 0.46 in the soft-water test. The toxicity of Temik toB. conchonius increases many fold in soft water.One of us (S. C. P.) is grateful to U. G. C., for the award of a senior research fellowship.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号