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51.
This study investigated whether potential emotional cues for drinking activate alcohol concepts in young drinkers. Participants were 84 university freshmen with high or low levels of anxiety sensitivity (AS). A verbal priming task measured activation (i.e., priming) of alcohol concepts (e.g., beer) by positive and negative mood phrases. Time to read alcohol target words was the dependent measure. Negative mood phrases consistently primed alcohol targets; positive mood phrases did not. Degree of negative mood priming did not differ as a function of gender or AS. Reported tendency to drink in bad moods predicted negative mood priming in women, whereas men showed negative mood priming irrespective of their reported drinking tendency. A general association between negative mood priming and severity of alcohol problems also emerged. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
概述 很多地方都需要测量温度。在设计温度遥测系统时,通常需要采用电池供电的极低功耗模块。传统的测温手段比较多,但不论是采用分立晶体管、热敏电阻,或者是热电偶,功耗都降不下来。本文介绍了一种满足低功耗要求的可行方案(如图1所示),该方案使用一枚极低功耗的、带Flash存储器的MCU,以及数字温度传感器、液晶模块(LCD)和一个32kHz的钟表用振荡器。该方案的突出特点是节能耐用,仅需一枚纽扣电池,就可以连续工作10年以上。  相似文献   
53.
The thymus represents the major site of the production and generation of T cells expressing alphabeta-type T-cell antigen receptors. Age-related involution may affect the ability of the thymus to reconstitute T cells expressing CD4 cell-surface antigens that are lost during HIV infection; this effect has been seen after chemotherapy and bone-marrow transplantation. Adult HIV-infected patients treated with highly active antiretroviral therapy (HAART) show a progressive increase in their number of naive CD4-positive T cells. These cells could arise through expansion of existing naive T cells in the periphery or through thymic production of new naive T cells. Here we quantify thymic output by measuring the excisional DNA products of TCR-gene rearrangement. We find that, although thymic function declines with age, substantial output is maintained into late adulthood. HIV infection leads to a decrease in thymic function that can be measured in the peripheral blood and lymphoid tissues. In adults treated with HAART, there is a rapid and sustained increase in thymic output in most subjects. These results indicate that the adult thymus can contribute to immune reconstitution following HAART.  相似文献   
54.
Ninety-four undergraduates participated in a computer-assisted, therapist empathy, or therapist empathy + input dream session. Although all conditions were rated positively, both therapist conditions were rated higher than the computer condition, and action ideas were better for the therapist empathy condition than for the other 2 conditions at postsession. At follow-up, the therapist empathy + input was rated higher than the empathy condition, which was higher than the computer condition. Participants in all conditions liked gaining awareness/insight, associations, and the approach to working with dreams; participants in both therapist conditions liked their therapist; participants in the empathy condition liked waking life links. Therapist condition participants mentioned fewer disliked things but complained more about research procedures; computer participants complained about the computer program and not working with a person. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
A clinical procedure for rapid detection of human immunodeficiency virus type 1 (HIV-1) by DNA amplification is demonstrated. The rapid procedure reduces handling requirements and amplification time and eliminates use of radioactivity for the detection of the amplification product. Total leukocyte lysates are the amplification substrates. Two conserved regions in the HIV-1 genome are amplified by 45 cycles of a two-temperature thermal cycle and the amplification products are detected by ultraviolet light after electrophoresis on agarose gels. Twenty-four specimens clinically diagnosed by detection of antibody (IgG) to HIV-1 were confirmed by the rapid DNA amplification procedure. In a blind study, 56 samples positive for HIV-1 DNA were detected in 503 individuals by the current classical polymerase chain reaction method; the same 56 positive samples were also detected by the rapid amplification protocol. No false-positive or false-negative results were obtained. The turnaround time for analysis has been reduced to < 24 h without compromising test results.  相似文献   
56.
This study tested the hypothesis that negative affective (NEG) cues activate alcohol concepts more strongly in problem drinkers with high rather than low psychiatric distress (PD) and that a parallel difference applies to activation of NEG concepts by alcohol cues. A lexical decision task assessed memory activation in 36 problem drinkers with high vs. low scores on the Symptom Checklist-90. High PD drinkers displayed activation in each condition, low PD drinkers displayed inhibition. Activation of alcohol concepts by NEG cues correlated with intensity of PD, bias to drink in NEG states, and confidence to avoid drinking in these states. Results corroborate in vivo cue reactivity studies and indicate a functional difference between problem drinkers with high and low PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
We determined the relative minimal inhibitory and minimal amoebicidal concentrations of chlorhexidine digluconate and polyhexamethylene biguanide for four species of Acanthamoeba. The amoebae were grown in peptone-glucose-yeast extract broth for 72 h in tissue culture flasks. Either washed trophozoites (approximately 10(5)) or cysts (approximately 10(5)) were incubated in the enrichment broth in 96 well microtiter trays. Antimicrobial concentrations of the biguanides were determined from microscopic examinations of methylene blue uptake and from subcultures. In general, killing was time dependent. Minimal amoebicidal concentrations at 24 h ranged from 50 to 100 mg/ml and to as low as 25 mg/ml by 72 h. Trophozoites were killed more rapidly than cysts. Both biguanides had similar levels of activity. A synergistic combination of chlorhexidine and polyhexamethylene biguanide (total concentration 25 mg/ml) was most evident for A. castellanii and A. polyphaga. Cysts of A. culbertsoni and A. hatchetti stained more rapidly after exposure to the combination of biguanides than to the single biguanides, but there were no statistically significant differences in the final numbers of dead or stained cysts after exposure to the combination or to the single biguanides.  相似文献   
58.
Capsules are produced by over 90% of Staphylococcus aureus strains, and approximately 25% of clinical isolates express type 5 capsular polysaccharide (CP5). We mutagenized the type 5 strain Reynolds with Tn918 to target genes involved in CP5 expression. From a capsule-deficient mutant, we cloned into a cosmid vector an approximately 26-kb EcoRI fragment containing the transposon insertion. In the absence of tetracycline selection, Tn918 was spontaneously excised, thereby resulting in a plasmid containing 9.4 kb of S. aureus DNA flanking the Tn918 insertion site. The 9.4-kb DNA fragment was used to screen a cosmid library prepared from the wild-type strain. Positive colonies were identified by colony hybridization, and a restriction map of one clone (pJCL19 with an approximately 34-kb insert) carrying the putative capsule gene region was constructed. Fragments of pJCL19 were used to probe genomic DNA digests from S. aureus strains of different capsular serotypes. Fragments on the ends of the cloned DNA hybridized to fragments of similar sizes in most of the strains examined. Blots hybridized to two fragments flanking the central region of the cloned DNA showed restriction fragment length polymorphism. A centrally located DNA fragment hybridized only to DNA from capsular types 2, 4, and 5. DNA from pJCL19 was subcloned to a shuttle vector for complementation studies. A 6.2-kb EcoRI-ClaI fragment complemented CP5 expression in a capsule-negative mutant derived by mutagenesis with ethyl methanesulfonate. These experiments provide the necessary groundwork for identifying genes involved in CP5 expression by S. aureus.  相似文献   
59.
Open architecture controllers   总被引:5,自引:0,他引:5  
Open architectures for desktop computing revolutionized the office. The author looks at how computer numerical controllers for factory equipment may be next  相似文献   
60.
A functional ANOVA analysis of the thermal dissociation of RNA hybridized to DNA microarrays was used to improve discrimination between two soil microbial communities. Following hybridization of in vitro transcribed 16S rRNA derived from uncontaminated and 2,4,6-trinitrotoluene contaminated soils to an oligonucleotide microarray containing group- and species-specific perfect match (PM) probes and mismatch (MM) variants, thermal dissociation was used to analyze the nucleic acid bound to each PM-MM probe set. Functional ANOVA of the dissociation curves generally discriminated PM-MM probe sets when Td values (temperature at 50% probe-target dissociation) could not. Maximum discrimination for many PM and MM probes often occurred at temperatures greaterthan the Td. Comparison of signal intensities measured prior to dissociation analysis from hybridizations of the two soil samples revealed significant differences in domain-, group-, and species-specific probes. Functional ANOVA showed significantly different dissociation curves for 11 PM probes when hybridizations from the two soil samples were compared, even though initial signal intensities for 3 of the 11 did not vary.  相似文献   
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