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131.
B. D. Singh Ravi Prakash Singh R. B. Singh 《Cellular and molecular life sciences : CMLS》1981,37(4):363-364
Summary 2 tall and 7 dwarf strains of rice were sprayed with 0 or 40 g ml–1 GA3, 4 dwarf strains responded to exogenous GA3, and showed a markedly lower endogenous gibberellin content than the tall strains, while 2 dwarf strains did not respond to GA3 application and had considerably higher endogenous gibberellin levels than the tall ones. Amylase activity in germinating seeds showed a significant negative correlation with the endogenous gibberellin content. 相似文献
132.
Hari Pal Singh S. S. Kakar N. C. Ganguli 《Cellular and molecular life sciences : CMLS》1979,35(11):1429-1430
Summary Intrapertioneal administration of PGF2a in rats significantly increased testicular acid phosphatase (p<0.05), decreased hyaluronidase (p<0.05), whereas the activities of 5-nucleotidase, N-acetyl-B-glucosaminidase, B-galactosidase and uridine diphosphatase remained unaffected.Acknowledgment. We are grateful to Dr D. Sundaresan, for his interest in the study and to Mr B. M. Sharma for technical assistance. 相似文献
133.
K. Singh 《Cellular and molecular life sciences : CMLS》1978,34(4):433-434
Summary A study extending over a period of 2 years has been made on serum iron level of common Indian frogR. tigrina. Serum iron averages 99.4 g/100 ml in female and 92.60 g/100 ml in males. The serum iron concentration is relatively high from May to October. Starvation has been found to decrease the serum iron level from the 16th day onwards.Acknowledgment. Thanks are due to Professor Dr M. M. Goil, Head of the Zoology Department for guidance and help in various ways and to Professor Dr R. K. Sharma for valuable suggestions. 相似文献
134.
135.
Lu DH Yi M Mo SK Erickson AS Analytis J Chu JH Singh DJ Hussain Z Geballe TH Fisher IR Shen ZX 《Nature》2008,455(7209):81-84
The recent discovery of superconductivity in the iron oxypnictide family of compounds has generated intense interest. The layered crystal structure with transition-metal ions in planar square-lattice form and the discovery of spin-density-wave order near 130 K (refs 10, 11) seem to hint at a strong similarity with the copper oxide superconductors. An important current issue is the nature of the ground state of the parent compounds. Two distinct classes of theories, distinguished by the underlying band structure, have been put forward: a local-moment antiferromagnetic ground state in the strong-coupling approach, and an itinerant ground state in the weak-coupling approach. The first approach stresses on-site correlations, proximity to a Mott-insulating state and, thus, the resemblance to the high-transition-temperature copper oxides, whereas the second approach emphasizes the itinerant-electron physics and the interplay between the competing ferromagnetic and antiferromagnetic fluctuations. The debate over the two approaches is partly due to the lack of conclusive experimental information on the electronic structures. Here we report angle-resolved photoemission spectroscopy (ARPES) of LaOFeP (superconducting transition temperature, T(c) = 5.9 K), the first-reported iron-based superconductor. Our results favour the itinerant ground state, albeit with band renormalization. In addition, our data reveal important differences between these and copper-based superconductors. 相似文献
136.
T. P. Singh 《Cellular and molecular life sciences : CMLS》1967,23(12):1016-1017
Zusammenfassung
Mystus vittatus zeigt unter natürlichen Bedingungen jahreszeitliche Variationen des TSH Gehaltes der Hypophyse. Veränderung der Lichtverhältnisse kann diesen TSH Zyklus beeinflussen: Dauerlicht verschiebt die Phasen, Dauerdunkel unterdrückt die zyklischen Veränderungen auf einen geringen Aktivitätsgrad. 相似文献
137.
Zusammenfassung Es wird ein Test angewendet, der native und denaturierte DNS unterscheiden lässt. Er besteht auf einer Verklumpung nativer DNS bei Zugabe von kationisierten Stoffen, während denaturierte DNS nur eine Trübung, respektive einen Niederschlag gibt. 相似文献
138.
C Kaschka-Dierich A Adams T Lindahl G W Bornkamm G Bjursell G Klein B C Giovanella S Singh 《Nature》1976,260(5549):302-306
Tumour biopsies from Burkitt lymphoma patients, as well as human nasopharyngeal carcinoma cells growing in athymic mice, contain Epstein-Barr virus DNA as covalently closed circular DNA. In addition integrated viral DNA sequences seem to be present. 相似文献
139.
Synthesis of Schiff bases of naphtha[1,2-d]thiazol-2-amine and metal complexes of 2-(2′-hydroxy)benzylideneaminonaphthothiazole as potential antimicrobial agents 下载免费PDF全文
Objective: A series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipophilic naphthalene ring to render them more capable of penetrating various biomembranes. Methods: Schiff bases were synthesized by the reaction of naphtha[1,2-d]thiazol-2-amine with various substituted aromatic aldehydes. 2-(2′-Hydroxy)benzylideneaminonaphthothiazole was converted to its Co(II), Ni(II) and Cu(II) metal complexes upon treatment with metal salts in ethanol. All the compounds were evaluated for their antibacterial activities by paper disc diffusion method with Gram positive Staphylococcus aureus and Staphylococcus epidermidis and Gram negative Escherichia coli and Pseudomonas aeruginosa bacteria. The minimum inhibitory concentrations of all the Schiff bases and metal complexes were determined by agar streak dilution method. Results: All the compounds moderately inhibited the growth of Gram positive and Gram negative bacteria. In the present study among all Schiff bases 2-(2′-hydroxy)benzylideneaminonaphthothiazole showed maximum inhibitory activity and among metal complexes Cu(II) metal complex was found to be most potent. Conclusion: The results obtained validate the hypothesis that Schiff bases having substitution with halogens, hydroxyl group and nitro group at phenyl ring are required for the antibacterial activity while methoxy group at different positions in the aromatic ring has minimal role in the inhibitory activity. The results also indicated that the metal complexes are better antibacterial agents as compared to the Schiff bases. 相似文献
140.
Oxygen free high conductivity (OFHC) copper was subjected to 1, 5, 10, 15 and 20 cycles of repetitive upsetting and extrusion (RUE) process at room temperature. Microstructure and microhardness in the RUE processed material were evaluated at specific locations and correlated with the equivalent plastic strain. The microhardness of the material was found to be independent of strain or number of RUE cycles at certain locations whereas it exhibited strain softening behaviour at certain locations even though significant grain refinement was achieved. This difference in behaviour is attributed to the varied strength contribution from different types of boundaries present in the material after deformation. 相似文献