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11.
The rif d18 bacteriophage carries essential parts of the E. coli genome which can not be mapped by conventional methods. The phage DNA was analysed with four restriction endonucleases (endo R. BamHI, Sall, HpaI and EcoRI) and a physical map was constructed. 相似文献
12.
Imre Mezö János Seprödi Judit Érchegyi István Teplán Magdolna Kovacs Bela Flerkó 《Peptides》1983,4(2):149-151
Inhibitory analogues of luteinizing hormone-releasing hormone (LH-RH) were prepared with formyl-D-Trp1, acetyl-D-Trp1, valeryl-D-Trp1, tartaryl-D-Trp1, diacetyl-tartaryl-D-Trp1, acetyl-Gly1, and acetyl-Sar1 successively replacing the position one in the analogue [D-Trp1, D-p-Cl-Phe2, D-Trp3, D-Phe6, D-Ala10]-LH-RH. The formyl-D-Trp1 and acetyl-D-Trp1 analogues yielded 100% blockade of ovulation at the 10 μg dose; the others were less potent and inhibited ovulation at the 50 μg dose. The inhibitory potency seems to correlate with the polarity of the acyl group. 相似文献
13.
The mode of action of chemically different herbicides (ureas, pyridazinones, phenylcarbamates, triazines, hydroxyquinolines, hydroxybenzonitriles and dinitrophenols) on photosynthetic electron transport was investigated by measurements of oxygen evolution and thermoluminescence. Depending on the particular herbicide used the thermoluminescence band related to Q (the primary acceptor of Photosystem II) appears at +5, 0 or −14°C. It was shown that these three different peak positions can be ascribed to various redox states of Q, the shifts being due to the binding of herbicides to the chloroplast membrane. Both displacement experiments and additive inhibition of herbicide pairs measured by thermoluminescence and oxygen evolution suggested that the sites of action of these herbicides are on the same protein. However, herbicide treatment of trypsinized chloroplasts showed that there were three different binding sites on the same protein, in agreement with the classification of herbicides into three groups based on thermoluminescence measurements. Our results suggest that the primary and secondary acceptors of Photosystem II (Q and B, respectively) are in close proximity and form a common complex with the herbicide-binding protein within the chloroplast membrane. 相似文献
14.
The genusGeitleria (Cyanophyceae orCyanobacteria): Distribution ofG. calcarea andG. floridana n. sp.
E. Imre Friedmann 《Plant Systematics and Evolution》1979,131(3-4):169-178
The calcifying cave inhabitant atmophytic blue-green algaGeitleria calcarea is reported from new localities in Florida and in the Cook Islands.—G. floridana n. sp., is described from caves in Florida. The calcified sheath has the shape of a quadratic prism and is built of crystalline acicular subunits about 0.1 µm in diameter. The subunits mostly form a rhombic lattice pattern but in some cases, they are not distinguishable and then the surface of the sheath is smooth.This paper is dedicated with gratitude to my former teacher, Prof. Dr.Lothar Geitler, for his 80th birthday. 相似文献
15.
A remarkable increase in the production of superoxide radicals and SOD activity was measured in suspension of the murine macrophage cell line C4M phi treated with Lentinan (4-10 X 10(3) micrograms/5 X 10(6) cells). In activated macrophages the decrease of lipid peroxidation could be interpreted as a consequence of enhanced SOD activity. 相似文献
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Ran Zhang Zhihui Zhao Yaofeng Zhao Imre Kacskovics Marjolein van der Eijk Nanda de Groot 《Animal biotechnology》2013,24(4):242-246
In this study, we evaluated haplotypes of the bovine FCGRT (encoding the FcRn heavy chain) and their relationship to the IgG concentration in bovine colostrum. Four single nucleotide polymorphism (SNP), classified into five haplotypes, were identified in a total of 49 Holstein-Frisians cows. Haplotype 5 was found to be significantly associated with a high IgG level ([OR] = 9.90, 95%CI = 1.11–88.34, p = 0.016) and haplotype 2 exhibited a similar trend ([OR] = 2.89, 95%CI = 1.17–7.11, p = 0.019). 相似文献
19.
Imre Berger Martin Egli Nada Spackova Jiri Sponer Alexander Rich 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1583-1585
Abstract DNA fragments with stretches of cytosine residues can form four-stranded intercalated i-DNA molecules stabilized by hemiprotonated cytosine·cytosine+ (C·C+) base pairs. Intriguing features of this motif are the accomodation of base stacking that is unfavorable due to electrostatic repulsion and the close approach of phosphates in narrow grooves of the molecule. Unusual sources of stability in this structure involve sugar-base stacking and CH-O interribose short contacts between the backbones of adjacent strands. 相似文献
20.
Jean M. J. Tronchet Imre Kovács Françoise Barbalat-Rey Margarita VegaHolm 《Nucleosides, nucleotides & nucleic acids》2013,32(6):1115-1123
Abstract Reaction of 2′,5′-di-O-TBDMS-3′-ketouridine 1 with L-cysteine yielded in good yield a resolvable mixture of the two expected epimeric spironucleosides 2 and 3. Amidification of their carboxylic group took place readily and the ribo carboxamide 4 was oxidized to the corresponding sulfoxide 6. Despite their similarity to TSAO derivatives these compounds did not exhibit usable anti-HIV activity. 相似文献