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41.
cDNA clones for the X-linked PGK-1 were obtained from a tammar wallaby liver by PCR and sequenced. The PGK-1 gene published here is the consensus sequence of those clones. The sequence represents an open reading frame of 1251 bp. Sequence comparisons to X-linked and autosomal sequences showed the greatest homology with the X-linked PGK-1 genes in eutherian species. This sequence opens the way for studying the paternal X inactivation phenomenon in marsupials and will assist in defining the time course of mammalian evolution. 相似文献
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Alan C. L. Yu 《PloS one》2010,5(8)
Variation is a ubiquitous feature of speech. Listeners must take into account context-induced variation to recover the interlocutor''s intended message. When listeners fail to normalize for context-induced variation properly, deviant percepts become seeds for new perceptual and production norms. In question is how deviant percepts accumulate in a systematic fashion to give rise to sound change (i.e., new pronunciation norms) within a given speech community. The present study investigated subjects'' classification of /s/ and // before /a/ or /u/ spoken by a male or a female voice. Building on modern cognitive theories of autism-spectrum condition, which see variation in autism-spectrum condition in terms of individual differences in cognitive processing style, we established a significant correlation between individuals'' normalization for phonetic context (i.e., whether the following vowel is /a/ or /u/) and talker voice variation (i.e., whether the talker is male or female) in speech and their “autistic” traits, as measured by the Autism Spectrum Quotient (AQ). In particular, our mixed-effect logistic regression models show that women with low AQ (i.e., the least “autistic”) do not normalize for phonetic coarticulation as much as men and high AQ women. This study provides first direct evidence that variability in human''s ability to compensate for context-induced variations in speech perceptually is governed by the individual''s sex and cognitive processing style. These findings lend support to the hypothesis that the systematic infusion of new linguistic variants (i.e., the deviant percepts) originate from a sub-segment of the speech community that consistently under-compensates for contextual variation in speech. 相似文献
44.
The particulate enzyme fraction from pig aorta was treated with Triton X-100 or Nonidet P-40 to yield a soluble enzyme preparation. This solubilized enzyme catalyzed the transfer of mannose from GDP-[14C]mannose, but not from [14C]mannosyl-phosphoryl-polyprenol, to G1cNAc-G1cNAc-pyrophosphoryl-polyprenol to form the trisaccharide-lipid, Man-β-GlcNAc-GlcNAc-pyrophosphoryl-polyprenol. The trisaccharide-lipid formed in these reactions was isolated by solvent fractionation and was subjected to mild acid hydrolysis to release the [14C]trisaccharide. Essentially all of the radioactivity was released from this trisaccharide as mannose upon treatment with β-mannosidase while α-mannosidase had no effect. 相似文献
45.
Alan G. Clews 《CMAJ》1980,123(7):692-693
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The light-induced free-radical signal of Photosystem II (observed after illumination at 77 °K) has been studied in chloroplasts as a function of the oxidation-reduction potential established prior to freezing. The intensity of the light-induced signal is unchanged in the potential region of +590 mV to +760 mV. At higher potential (+850 mV), there is a 30% decrease in signal intensity. The light-induced signal decreases to zero in the low-potential region, with a midpoint potential of +475 mV. These results are considered in terms of a Photosystem II reaction-center complex in which the light-induced free-radical signal arises from the oxidized form of the reaction-center chlorophyll, and this chlorophyll molecule is capable of being reduced at liquid-nitrogen temperature by a secondary electron donor which has a midpoint oxidation-reduction potential of +475 mV. 相似文献
49.
In Experiment 1, all ewes were treated with follicle stimulating hormone (FSH-P) to induce superovulation. Ewes came into natural estrus or were treated with prostaglandin F(2)alpha (PGF(2)alpha) or 6-methyl-17-acetoxyprogesterone (MAP) to regulate the time of estrus. The ewes were mated during estrus and necropsied 3 h after mating. Regulation of estrus with either compound reduced the number of sperm recovered from the cervix, uterus, and oviducts and increased the proportions of sperm recovered from the cervix and uterine body that were immotile, dead, or had disrupted membranes. In Experiment 2, all ewes were in natural estrus. They either ovulated naturally or were superovulated, and ewes in each group were necropsied at 3 or 23 h after mating. Superovulation reduced the number of sperm in oviducts, uterus, and anterior segments of the cervix at both time intervals and increased the proportions of sperm that were immotile, dead, or had disrupted membranes. In Experiment 3, of 3x2 design, ewes were in either natural estrus or estrus regulated with PGF(2)alpha or with MAP; they ovulated naturally or were superovulated. Ewes were necropsied 3 d after mating and ova were examined. Both regulation of estrus and superovulation reduced the proportion of ova that were fertilized and reduced the number of accessory sperm attached to fertilized ova. 相似文献
50.
2-Phenylethylamine catabolism by Escherichia coli K12 总被引:1,自引:0,他引:1
Escherichia coli K12 grows on 2-phenylethylamine as sole carbon and energy source by converting it, via phenylacetaldehyde, to phenylacetic acid. Phenylacetaldehyde was formed by the action of an inducible amine oxidase and catalase activity was increased sixfold, presumably to ensure removal of the H2O2 that was expected to be a product of the amine oxidation. The phenylacetaldehyde was oxidized to phenylacetic acid by an inducible NAD+-dependent dehydrogenase. Mutants defective in phenylacetaldehyde dehydrogenase cannot grow on 2-phenylethylamine as carbon and energy source but can still use it as a nitrogen source. 相似文献