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991.
Three studies, involving 146 undergraduates and 68 heterosexual couples, assessed the construct validity of the self- and other-model dimensions underlying the 4-category model of adult attachment. Five methods were used to assess the hypothesized dimensions: self-reports, friend-reports, romantic partner reports, trained judges' ratings of peer attachment, and trained judges' ratings of family attachment. Study 2 related the latent attachment dimensions to theoretically relevant outcome latent variables. As predicted, Ss' self models converged with direct measures of the positivity of their self-concepts, and Ss' other models converged with direct measures of the positivity of their interpersonal orientations. Study 3 related the latent attachment dimensions to 3 alternate self-report measures of adult attachment and showed that the 2 dimensions served as an organizing framework for the different measurement approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A polymerase chain reaction (PCR) assay was developed to rapidly detect and identify West Nile (WN) virus. The RNA from seven isolates of WN virus from six countries and four other flaviviruses (Kunjin, Japanese encephalitis, St. Louis encephalitis, and yellow fever viruses) was reverse-transcribed (RT) and amplified by PCR. The nucleotide sequences of the amplified products were determined by a rapid, automated DNA sequencing method. The WN virus RT/PCR assay detected the target gene segment of sequencing method. The WN virus RT/PCR assay detected the target gene segment of isolates from both the African-Middle Eastern group and the Indian group with a sensitivity of approximately 0.05 pg of viral RNA. Kunjin virus was the only other flavivirus tested that produced a band of the appropriate size. Five of seven WN virus isolates showed 92-98% homology in the nucleotide sequence of their PCR products. The sequence of one isolate was virtually identical to the published sequence of the Nigerian isolate (99.5% homology). No correlation was established between the degree of nucleotide homology, geographic location, time of isolation, or source of the isolates.  相似文献   
995.
We have used a negative glucocorticoid response element (nGRE) from the bovine prolactin promoter linked to the gene for chloramphenicol acetyltransferase (PRL3CAT) to study the inhibition of gene expression by steroid hormone receptors. This nGRE increased basal expression from a heterologous promoter in COS-7 cells. In the presence of cotransfected glucocorticoid (GR), androgen, or progesterone receptor (PR) expression vectors and their cognate ligands, the expression of PRL3CAT could be repressed, indicating that these steroid receptor subfamily members could function through the same negative response element. No repression was observed with the estrogen receptor, showing that the repressive effect was specific for members of the GR-subfamily. Mutation of three amino acids within the GR-DNA binding domain that determine the specificity of GR-GRE interaction abolished the ability of the GR to inhibit the expression of PRL3CAT, demonstrating the requirement for DNA binding of the GR in the mechanism of repression. The antiglucocorticoid/antiprogestin RU486 when bound to PR or GR also repressed the expression of the PRL3CAT, but higher concentrations of RU486 were required to obtain an effect with the GR when compared to the PR. RU486 was unable to antagonize the effect of progestins on PRL3CAT and only partially antagonized the glucocorticoid repression. Thus, regarding the repression of PRL3CAT, RU486 acted as an agonist when bound to the PR and as a partial agonist when bound to the GR.  相似文献   
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Rat brain cortex slices and synaptosomes preincubated with [3H]noradrenaline were used to investigate whether the NMDA-evoked noradrenaline release is modulated by agonists or antagonists at presynaptic alpha 2-adrenoceptors. In experiments on slices, noradrenaline and the preferential alpha-adrenoceptor agonists talipexole (former B-HT 920) and clonidine inhibited the NMDA-evoked tritium overflow whereas the selective alpha 1-adrenoceptor agonists cirazoline and methoxamine were ineffective. The alpha 2-adrenoceptor antagonists rauwolscine and idazoxan facilitated the NMDA-evoked tritium overflow whereas the preferential alpha 1-adrenoceptor antagonist prazosin was ineffective. The concentration-response curve of talipexole for its inhibitory effect on NMDA-evoked overflow was shifted to the right by idazoxan (apparent pA2 = 7.5). The EC50 of NMDA (97 mumol/l) for its stimulating effect on tritium overflow was not substantially changed by blockade of alpha 2-autoreceptors with 1 mumol/l rauwolscine (EC50 of NMDA in the presence of the alpha 2-adrenoceptor antagonist, 155 mumol/l), but the maximal overflow of tritium was increased 2.5 fold by this rauwolscine concentration. In experiments on synaptosomes, talipexole and noradrenaline inhibited the NMDA-evoked tritium overflow. The inhibitory effect of talipexole was abolished by idazoxan which, given alone, was ineffective, as was prazosin. Talipexole did also not produce an inhibition when tritium overflow was evoked by NMDA in the presence of omega-conotoxin GVIA 0.1 mumol/l; the latter, by itself, decreased the response to NMDA by about 55%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
Models of high velocity impact phenomena   总被引:1,自引:0,他引:1  
Models of craters formed by impacts at velocities of up to 24.5 km/sec have been computed using the Smooth Particle Hydrodynamics, MESA, EPIC and CALE codes. These modeling efforts are compared to data obtained from the Hypervelocity Microparticle Impact project at Los Alamos using the van de Graaff accelerator. A factor of 5 increase in yield strength was needed to account for high strain rate effects and to match the data. Structure in the data is addressed by using crater volume instead of crater diameter cubed. Detailed code comparisons were made between the four codes with good agreement found.  相似文献   
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