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91.
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93.
The effect of tributyltin‐chloride (TBTC), dibutyltin‐chloride (DBTC) and monobutyltin‐chloride (MBTC) on rainbow trout (Salmo irideus) nuclear DNA, was investigated by means of single cell gel electrophoresis (‘comet’ assay). Our data show that TBTC presents a marked genotoxic effect, whereas the genotoxic effect is less pronounced for DBTC and it is completely absent for MBTC. These results could be important in evaluating the environmental risks deriving from the use of these molecules as a antifouling agents in marine paints and as agricultural biocides. Copyright © 2001 John Wiley & Sons, Ltd.
Abbreviations:
-
- TBTC,
-
- tributyltin‐chloride;
-
- DBTC,
-
- dibutyltin‐chloride;
-
- MBTC,
-
- monobutyltin‐chloride;
-
- Hb,
-
- hemoglobin.
94.
Felix A. E. Pirani 《General Relativity and Gravitation》2009,41(5):1215-1232
This Golden Oldie is a reprinting of a paper by F. A. E. Pirani first published in 1956. It is accompanied by a reprinting
of a paper by J. L. Synge first published in 1934. Together these papers pointed the way to the interpretation of geodesic
deviation and its relation to the curvature tensor. These two Golden Oldies are accompanied by an Golden Oldie Editorial containing
an editorial note written by A. Trautman, and by the biography of F. Pirani written by himself and commented by A. Trautman.
An editorial note to this paper and a biography can be found in this issue preceding this Golden Oldie and online via doi:.
Original paper: F. A. E. Pirani, Acta Physica Polonica 15, 389–405 (1956). Reprinted with the kind permission of the Editors of Acta Physica Polonica, and of Felix Pirani. 相似文献
95.
Pier Luigi Barili Maria Camilla Bergonzi Giancarlo Berti Giorgio Catelani Felicia D'Andrea Francesco De Rensis 《Journal of carbohydrate chemistry》2013,32(9):1037-1049
ABSTRACT The title compound, previously unreported in either enantioform, and its 2,6-di-O-benzyl derivative have been synthesized through a stereocontrolled epimerization at C-2 of 6-O-protected methyl 3,4-O-isopropylidene-5-C-methoxy-β-D-galactopyranosides. The epimerization, performed through a high yielding sequence of oxidation-reduction owing to the cooperative role of the equatorial C-1 aglycon and the steric hindrance of the isopropylidene group, turned out to be completely diastereoselective. Whereas the unprotected L-ribo-hexos-5-ulose exists, as proved by NMR in D2O, in five main tautomeric forms in a ratio of about 4:2:2:1:1, only two anomeric 1,4-furanosic forms are present at equilibrium in its 2,6-di-O-benzyl derivative, in ratios ranging from 10:1 to 7:3, depending on the prevalence of D2O or CD3CN in the solvent mixture. 相似文献
96.
Pier Luigi Barili Giancarlo Berti Giorgio Catelani Felicia D'Andrea Francesco De Rensis Giampaolo Goracci 《Journal of carbohydrate chemistry》2013,32(8):1167-1180
Abstract The unreported title compound and its 2,6-di-O-benzyl derivative have been prepared from methyl β-D-galactopyranoside through a sequence involving the bisglycoside methyl 2,6-di-O-benzyl-5-O-methoxv-β-D-galactopyranoside 8, the precursor of L-orabino-hexos-5-ulose, that was converted to the L-lyxo series by inversion at C-3. The inversion was achieved in acceptable yields by selective triflation, followed by displacement with benzoate, and by an oxidation/reduction sequence. Whereas 2,5-di-O-benzyl-L-lyxo-hexos-5-ulose exists entirely as a mixture of the two anomeric 1,4-furanosic forms, the unprotected hexos-5-ulose involves at equilibrium in CD3CN/D2O at least eight tautomers, one of which is predominant. 相似文献
97.
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99.
Raffaele Giancarlo Roberto Grossi 《Journal of Algorithms in Cognition, Informatics and Logic》1997,24(2):223-265
We introduce a new multidimensional pattern matching problem that is a natural generalization of string matching, a well studied problem[1]. The motivation for its algorithmic study is mainly theoretical. LetA[1:n1,…,1:nd] be a text matrix withN = n1…ndentries andB[1:m1,…,1:mr] be a pattern matrix withM = m1…mrentries, whered ≥ r ≥ 1 (the matrix entries are taken from an ordered alphabet Σ). We study the problem of checking whether somer-dimensional submatrix ofAis equal toB(i.e., adecisionquery).Acan be preprocessed andBis given on-line. We define a new data structure for preprocessingAand propose CRCW-PRAM algorithms that build it inO(log N) time withN2/nmaxprocessors, wherenmax = max(n1,…,nd), such that the decision query forBtakesO(M) work andO(log M) time. By using known techniques, we would get the same preprocessing bounds but anO((dr)M) work bound for the decision query. The latter bound is undesirable since it can depend exponentially ond; our bound, in contrast, is independent ofdand optimal. We can also answer, in optimal work, two further types of queries: (a) anenumerationquery retrieving all ther-dimensional submatrices ofAthat are equal toBand (b) anoccurrencequery retrieving only the distinct positions inAthat correspond to all of these submatrices. As a byproduct, we also derive the first efficient sequential algorithms for the new problem. 相似文献
100.
The nitration of diphenylmethane to three main isomeric dinitro derivatives, performed with nitric acid in dichloromethane, is proposed as an organic laboratory experiment showing a number of advantages over typical aromatic nitrations in sulfuric acid. 相似文献