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31.
Simultaneous communications combines both spoken and manual modes to produce each word of an utterance. This study investigated the potential influence of alterations in the temporal structure of speech produced by inexperienced signers during simultaneous communication on the perception of final consonant voicing. Inexperienced signers recorded words that differed only in the voicing characteristic of the final consonant under two conditions: (1) speech alone and (2) simultaneous communication. The words were subsequently digitally edited to remove the final consonant and played to 20 listeners who, in a forced-choice paradigm, circled the word they thought they heard. Results indicated that accurate perception of final consonant voicing was not impaired by changes in the temporal structure of speech that accompanied the inexperienced signers' simultaneous communication.  相似文献   
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Characterization of the region between HLA-B and the TNF loci in the human MHC revealed the presence of duplicated loci, named CL1 and CL2, that included repeat sequences. Development and use of a PCR typing methodology that amplified both CL microsatellites simultaneously indicated that PCR product patterns analysed on native agarose gels were allelic (Abraham et al., 1992). The purpose of the current study was to determine the molecular explanation for the unique patterns achieved. Sequence analysis of the CL1 locus from 32 chromosomes representing 10 ancestral haplotypes indicated that six alleles were present. The CL microsatellites also provided an opportunity to study the evolutionary relationships between MHC haplotypes from different racial groups. Sequence comparison of closely related ancestral haplotypes from different racial groups suggested that the CL1 microsatellite has not changed in the period since divergence.  相似文献   
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A memory-based processing approach to discourse comprehension emphasizes the rapid deployment of information in memory to facilitate understanding of the text that is currently being read. S. B. Greene, R. J. Gerrig, G. McKoon, and R. Ratcliff (1994) demonstrated that when a text described the reunion of 2 characters who had previously discussed a 3rd character, the accessibility of the 3rd character increased, and the use of an unheralded pronoun (R. J. Gerrig, 1986) to refer to that character was felicitous. In experiments in this article, the authors demonstrate that concepts related to the unheralded pronoun also increase in accessibility and that those concepts form associations in memory with concepts present in the discourse at the time the pronoun is used. The authors also show that the increase in accessibility for the referent of the pronoun, as well as the appropriate long-term memory associations, occurs even in the absence of the pronoun.  相似文献   
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Mouse hepatitis virus (MHV), a murine coronavirus known to cause encephalitis and demyelination, uses murine homologues of carcinoembryonic antigens as receptors. However, the expression of these receptors is extremely low in the brain. By low-stringency screening of a mouse brain cDNA library, we have identified a member of the pregnancy-specific glycoprotein (PSG) subgroup of the carcinoembryonic antigen gene family. Unlike other PSG that are expressed in the placenta, it is expressed predominantly in the brain. Transfection of the cDNA into COS-7 cells, which lack a functional MHV receptor, conferred susceptibility to infection by some MHV strains, including A59, MHV-2, and MHV-3, but not JHM. Thus, this is a virus strain-specific receptor. The detection of multiple receptors for MHV suggests the flexibility of this virus in receptor utilization. The identification of this virus in receptor utilization. The identification of a PSG predominantly expressed in the brain also expands the potential functions of these molecules.  相似文献   
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Identification of infecting Mycoplasma spp. is difficult and not routine for strain. This paper describes a procedure for the rapid identification of the strain of M. gallisepticum. Monoclonal antibodies were prepared against M. gallisepticum F and M. gallisepticum S6. Aliquots of 24-hour broth cultures of these organisms were incubated briefly with either of the monoclonal antibodies. A second incubation was made with anti-mouse immunoglobulin conjugated to fluorescein isothiocyanate. Fluorescent intensity associated with the organisms was measured with a flow cytometer. The criterion for identification was a comparative increase in fluorescent intensity when the strain and monoclonal antibody were homologous. The procedure correctly differentiated the F and S6 strains of M. gallisepticum in a blind study.  相似文献   
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Using high-performance liquid chromatography, gas-chromatography and chromato-mass spectrometry methods a novel endogenous cyclic dipeptide cyclo-prolylglycine was identified in rat brain. Its content according to gas chromatography is 2.8 +/- 0.3 nmol/g wet brain. Synthetic cyclo-prolylglycine has demonstrated antiamnesic activity in the passive avoidance test in rats at a dose of 0.1 mg/kg i.p. Cyclic dipeptide cyclo-prolylglycine seems to be a memory facilitating substance and its presence in rat brain suggests the existence of a new mechanism of memory regulation.  相似文献   
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Presynaptic alpha 2-autoreceptors in mouse atria were characterized in terms of the alpha 2A, alpha 2B, alpha 2C and alpha 2D subtypes. Segments of the atria were preincubated with 3H-noradrenaline and then superfused and stimulated electrically. The affinity of up to 16 antagonists for the autoreceptors was assessed as (1) pEC30% values. i.e. concentrations that increased previously autoinhibited release of 3H-noradrenaline (120 pulses, 3 Hz) by 30%, and (2) pKd values against the release-inhibiting effect of 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline (UK 14,304) under conditions of no or little autoinhibition (2 trains of 20 pulses, 50 Hz, train interval 120 s). The pKd values correlated well with the pEC30% values (r = 0.98; P < 0.001; slope of regression line 0.93), indicating that UK 14,304 and released noradrenaline modulated the release of noradrenaline through pharmacologically identical receptors. Comparison with antagonist affinities for (1) prototypic native alpha 2 radioligand binding sites, (2) radioligand binding sites in COS cells transfected with alpha 2 subtype genes, and (3) previously classified presynaptic alpha 2-autoreceptors-all taken from the literature-indicated that the mouse atrial autoreceptors corresponded to the alpha 2D subtype. For example, the pKd values at mouse atrial auto-receptors correlated closely with pKd values at native alpha 2D binding sites in the bovine pineal gland (r = 0.96; P < 0.001); with pKd values at alpha 2D binding sites in COS cells transfected with the rat alpha 2D gene (r = 0.85; P < 0.01); and with pKd values at guinea-pig cerebral and atrial and mouse cerebral alpha 2D-autoreceptors (r = 0.96-0.98; P < 0.001). The antagonist pKd values at mouse atrial autoreceptors correlated less with pKd values at alpha 2A, alpha 2B and alpha 2C sites. It is concluded that the presynaptic alpha 2-autoreceptors in mouse atria are alpha 2D. This identification supports the hypothesis that at least the majority of alpha 2-autoreceptors belong to the alpha 2A/D pair of orthologous alpha 2-adrenoceptors.  相似文献   
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