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991.
G Meunier C Paoletti B Meunier 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1984,299(15):629-632
9-methoxy ellipticine, an antitumor compound, is O-demethylated in presence of the system peroxidase-H2O2; this reaction yields the corresponding electrophilic quinone-imine and methanol. This O-demethylation reaction is reported for the first time and might be possibly extended to some other antitumor drugs. 相似文献
992.
Harder David B.; Capeless Christopher G.; Maggio John C.; Boughter John D. Jr; Gannon Kimberley S.; Whitney Glayde; Azen Edwin A. 《Chemical senses》1992,17(4):391-401
Mice have been characterized as either tasters or non-tastersof the bitter compound sucrose octa-acetate(SOA). However, 11of 17 supposedly non-taster inbred strains were found to avoid1 mM SOA. All 17 strains were indifferent to 0.1 mM SOA. Tasterstrains avoided both concentrations. The intermediate phenotypewas dubbed demitaster. A consistent phenotypic dominance orderwas found in crosses among both inbred and outbred strains (taster> non-taster > demitaster). Demitasters were found (withtasters) in an outbred strain showing monogenic segregationfor SOA avoidance. This, plus monogenic segregation in a back-crossof taster to demitaster inbred strains, suggested a third alleleat the Soa locus (Soac). Demitaster allelism was supported bythe strong associations found in 15 strains between the threeSOA phenotypes and HindIII restriction fragment patterns forthe closely linked Prp (proline rich protein) loci. SOA demitasterstrains were also intermediate in raffinose undeca-acetate (RUA)avoidance. Furthermore, B6.SW-Soa2 congenic mice avoided notonly SOA, but RUA and eight other acetylated sugars. A previouslyproposed separate RUA-sensitivity gene (Rua) thus appeared tobe redundant. 相似文献
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997.
N Bruneau P Arbeille M C Dourneau B Garreau L Pourcelot G Lelord 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1989,308(9):255-260
Transcranial Doppler ultrasonographic recordings of the middle cerebral arteries were performed on eight children with autistic behavior compared to eight controls. Blood flow measurements were assessed at rest and during auditory and visual stimulations. The main result was obtained during the auditory stimulations and concerned the left artery blood flow which is lower in autistics than in controls in these conditions (p less than .02). This result confirms the possibility of a left hemisphere dysfunctioning in autistics and may be related to clinical features as language disabilities and paradoxical reactivity to auditory stimuli. 相似文献
998.
A generalized Morse index theory is used to study travelling waves in a natural selection-migration model for a diploid organism when the selective strength is weak. 相似文献
999.
Shell shape and growth of two unionacean species, Villosa villosaand Elliptio icterina, are analyzed with univariate and multivariatetechniques. The relationship of shape variables to size variablesis examined. Under the lognormal assumption, parametric testsof these allometric relationships are valid. Variables describingthe ventro-posterior region of the shell are shown to be thebest of those tested for discriminating between the sexes ofboth species regardless of statistical method. Neither speciesexhibits size sexual dimorphism. Shape sexual dimorphism ofV. villosa is constant during adult growth, but the more subtledimorphism of E. icterina changes as adults continue to grow. (Received 20 January 1986; 相似文献
1000.