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991.
Intestinal-type fibroblasts selectively influence proliferation rate and peptide synthesis in the murine entero-endocrine cell line STC-1 总被引:1,自引:0,他引:1
992.
Improved Screening of cDNAs Generated by mRNA Differential Display Enables the Selection of True Positives and the Isolation of Weakly Expressed Messages 总被引:22,自引:1,他引:21
Zegzouti Hicham Marty Christel Jones Brian Bouquin Thomas Latché Alain Pech Jean Claude Bouzayen Mondher 《Plant Molecular Biology Reporter》1997,15(3):236-245
The high percentage of false positives generated by differential display (as high as 85%) has previously limited the potential of the method. This report describes an efficient methodology that enables false positives to be discarded prior to cloning, via reverse Northern analysis. This first step of the screening also allows the detection of putative low abundance differential clones. Following cloning, a second reverse Northern combined with partial DNA sequencing and RT-PCR detection allows isolation of all differential cDNAs including very low abundance clones. Use of the sequential screening procedure described here led to the isolation of novel tomato genes responding to the plant hormone ethylene while minimising labor and materials input. 相似文献
993.
With a view toward describing behavioral variability among individuals of the primitively eusocial speciesBelonogaster juncea juncea, we recorded the time-activity budget spent on five behavioral categories (foraging, building, feeding, inactivity, and reproduction)
by 52 individuals belonging to four postemergence colonies. A principal-components analysis coupled with a hierarchical cluster
analysis enabled us to discern four behavioral roles. The reproductive role is reserved to one individual (functional monogyny)
and the workers’ role is differentiated into foragers, builders, and guards. The foragers are females that spend the most
time (82.6% of their time) foraging, supplying the nest with prey load and liquid matter. The builders are individuals (with
41.5% of their time off the nest) that tend to bring pulp into the nest and then undertake building activities. The guards
are those females that spend the most time (79.7% of their time) being inactive on the nest. 相似文献
994.
Alain L. Bardou Pierre M. Auger Jean-Luc Chasse Renaud Seigneuric 《Acta biotheoretica》1997,45(3-4):227-236
Limitations of antiarrhythmic drugs on cardiac sudden death prevention appeared since the early 80's. The "Cardiac Arrhythmia
Suppression Trial"(CAST) showed more recently that mortality was significantly higher inpatients treated with some particular
antiarrhythmic drugs than in non-treated patients. In this field, our group recently demonstrated that a bolus of a Class
1B antiarrhythmic drug was able to trigger a ventricular fibrillation due to transient blocks induction.
The aim of the present work was to systematically study, by use of the van Capelle and Durrer (VCD) model which allows to
simulate ventricular activation wave propagation, the link between arrhythmogenic effects and the ability of transient blocks
to possibly degenerate in severe arrhythmias. A fragment of the ventricular wall is represented by an array of 16384elements
electrically coupled. Effects of induction of one or several transient blocks, as the effects of their size and duration on
possible induction of reentries have been studied. Results obtained show that various combinations between these different
parameters may trigger reentries, ventricular tachycardia and/or more complex patterns assimilable to ventricular fibrillation.
These results clearly evidence the fact that possible induction of transient blocks may directly be related to risk factor
associated to arrhythmogenic effects of antiarrhythmic drugs.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
995.
996.
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998.
Carmen Lapadatescu Gilles Feron Catherine Vergoignan Aleth Djian Alain Durand Pascal Bonnarme 《Applied microbiology and biotechnology》1997,47(6):708-714
Three white-rot basidiomycetes, Bjerkandera adusta, Ischnoderma benzoinum and Dichomitus squalens, were cultivated on a liquid medium supplemented with l-phenylalanine, a precursor for benzaldehyde (bitter almond aroma) and benzyl alcohol. Remarkable amounts of benzaldehyde
(587 mg l−1) were found in cultures of B. adusta. Immobilization of this fungus on polyurethane foam cubes allowed an 8.3-fold increase of the production of benzaldehyde
and a 15-fold increase of the productivity as compared with non-immobilized cells. Aryl-alcohol oxidase activity was only
detected in B. adusta. This activity was also significantly enhanced in immobilized cells, suggesting that it plays an important role in benzaldehyde
biosynthesis. Conversely, consistent amounts of benzyl alcohol (340 mg l−1 for B. adusta and I. benzoinum and 100 mg l−1 for D. squalens) were produced by the three fungi when immobilized. Laccase activity was found only in the strains I. benzoinum and D. squalens. This activity was markedly enhanced in free cells cultures. Immobilization of the fungi did not promote benzyl alcohol production
by comparison with free cell cultures (500 mg l−1).
Received: 10 December 1996 / Received revision: 17 February 1997 / Accepted: 22 February 1997 相似文献
999.
François-Yves Dupradeau Guillaume Le Flem Jean-Michel Wieruszeski Manuel Dauchez Alain Alix Véronique Larreta-Garde Jean-Pierre Monti 《International journal of peptide research and therapeutics》1997,4(4-6):489-495
Summary
1H-NMR studies of the bovine insulin S-sulfonated B-chain are reported in H2O/D2O (9/1) and in glycerol-d
5 (5 M) using two-dimensional NMR spectroscopy. The first results show that the oxidized insulin B-chain secondary structure
differs from that of native insulin by a loss of the α-helix between the two disulfide bridges and that the glycerol favours
the structuring of the peptide. 相似文献
1000.
Mathieu Marc Lehmann Christian Razaname Alain Tuchscherer Gabriele 《International journal of peptide research and therapeutics》1997,4(2):95-100
Summary The assembly of helical and β-sheet peptide blocks containing reactive chain ends results in highly branched chain architectures
(‘locked-in folds’) mimicking native tertiary structures. This molecular kit strategy allows to bypass the protein folding
problem in protein de novo design and gives access to protein mimetics of high thermodynamic stability. The validity of this
concept is exemplified for the design and synthesis of locked-in folds mimicking the zinc finger and MHC folding motifs. 相似文献