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22.
In this study, we investigated the induction of cellular gene expression by the Epstein-Barr Virus (EBV) latent membrane protein 1 (LMP1). Previously, LMP1 was shown to induce the expression of ICAM-1, LFA-3, CD40, and EBI3 in EBV-negative Burkitt lymphoma (BL) cells and of the epidermal growth factor receptor (EGF-R) in epithelial cells. We now show that LMP1 expression also increased Fas and tumor necrosis factor receptor-associated factor 1 (TRAF1) in BL cells. LMP1 mediates NF-kappaB activation via two independent domains located in its C-terminal cytoplasmic tail, a TRAF-interacting site that associates with TRAF1, -2, -3, and -5 through a PXQXT/S core motif and a TRADD-interacting site. In EBV-transformed B cells or transiently transfected BL cells, significant amounts of TRAF1, -2, -3, and -5 are associated with LMP1. In epithelial cells, very little TRAF1 is expressed, and only TRAF2, -3, and -5, are significantly complexed with LMP1. The importance of TRAF binding to the PXQXT/S motif in LMP1-mediated gene induction was studied by using an LMP1 mutant that contains alanine point mutations in this motif and fails to associate with TRAFs. This mutant, LMP1(P204A/Q206A), induced 60% of wild-type LMP1 NF-kappaB activation and had approximately 60% of wild-type LMP1 effect on Fas, ICAM-1, CD40, and LFA-3 induction. In contrast, LMP1(P204A/Q206A) was substantially more impaired in TRAF1, EBI3, and EGF-R induction. Thus, TRAF binding to the PXQXT/S motif has a nonessential role in up-regulating Fas, ICAM-1, CD40, and LFA-3 expression and a critical role in up-regulating TRAF1, EBI3, and EGF-R expression. Further, D1 LMP1, an LMP1 mutant that does not aggregate failed to induce TRAF1, EBI3, Fas, ICAM-1, CD40, and LFA-3 expression confirming the essential role for aggregation in LMP1 signaling. Overexpression of a dominant form of IkappaBalpha blocked LMP1-mediated TRAF1, EBI3, Fas, ICAM-1, CD40, and LFA-3 up-regulation, indicating that NF-kappaB is an important component of LMP1-mediated gene induction from both the TRAF- and TRADD-interacting sites.  相似文献   
23.
Formulation of the title problem using the Green's function of the beam or plate allows solution by the methods of classical modal analysis. These are briefly reviewed in this context and the necessary results are stated for both classically and nonclassically damped systems, the mean square response to stationary excitation being obtained in terms of spectral integrals. Some cases in which these can be evaluated analytically are examined.  相似文献   
24.
Individuals who perform well within an unsuccessful group have more favorable reactions than equally capable individuals who perform poorly within a successful group. This frog-pond effect appears to occur because people focus on their relative performance standing within their group rather than on their group's overall performance level. It was hypothesized that this effect would be attenuated among people who value their social groups highly because they should be more likely than their counterparts to take into account their group's performance level when evaluating themselves. Four studies supported this reasoning. The frog-pond effect was strongest among individuals with lower collective self-esteem, an individualistic cultural heritage, or a weaker bond toward a particular social group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
OBJECTIVES: To assess the impact of HIV counselling and testing on HIV seroconversion and incidence of reported sexually transmitted diseases (STDs) among male factory workers in Harare, Zimbabwe. DESIGN: Prospective, observational study among men recruited to participate in a future workplace based AIDS prevention intervention. METHODS: Participants provided STD histories and blood for HIV antibody testing at enrolment and six month intervals during visits to factories. Participants received HIV test results, post test counselling, and free STD services at the project clinic. RESULTS: Between March 1993 and June 1995, 2,414 men were enrolled with 85% follow up. Overall HIV sero-incidence was 2.60 per 100 person-years; the incidence of reported STDs was 10.19 per 100 person-years. Men who obtained their HIV test results had significantly higher HIV sero-incidence and incidence of reported STDs compared to men who did not obtain their results (IRRs: 1.87, 3.47, respectively). Among men who obtained their HIV test results, a non-significant 40% decrease in HIV sero-incidence was observed after obtaining test results compared to before obtaining results (p = 0.18). The incidence of reported STDs, however, increased by 30% after obtaining HIV test results (p = 0.10). CONCLUSIONS: Decreased HIV sero-incidence in the face of increased reported STD incidence suggests that timely treatment of STDs may decrease the risk of acquiring HIV even in the absence of behaviour change. In populations with high rates of HIV and STDs, the greatest benefit of HIV counselling and testing may be achieved by simultaneously offering STD screening and treatment services.  相似文献   
26.
Environmental regulations are driving R&D efforts to produce low sulfur fuels, including diesel fuel and gasoline for motor vehicles. Biocatalytic sulfur removal from fuels has potential applicability for producing low sulfur gasoline. Microbial biocatalysts have been identified that can biotransform sulfur compounds found in fuels, including ones that selectively remove sulfur from dibenzothiophene heterocyclic compounds. Most attention is give to the 4S pathway of Rhodococcus, which can remove sulfur from substituted and unsubstituted dibenzothiophenes, including sulfur compounds that hinder chemical catalysis and that resist removal by mild hydrotreatment. Various bioreactor and bioprocess designs are being tested for use with biocatalysts, including recombinant biocatalysts, for use in removing sulfur from fuels and feedstocks within the petroleum refinery stream. With bioprocess improvements that enhance biocatalyst stability, achieve faster kinetics, improve mass transfer limitations, temperature and solvent tolerance, as well as broaden substrate specificity to attack a greater range of heterocyclic compounds, biocatalysis may be a cost-effective approach to achieve the production of low sulfur gasoline. The challenge will be to accomplish these improvements by the time the regulations for low sulfur gasoline and other vehicle fuels go into effect in order to be competitive with emerging nonbiological desulfurization technologies.  相似文献   
27.
Accident epidemiology and the design of the residential environment   总被引:2,自引:0,他引:2  
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28.
Reports an error in "Counselor deliberate postural lean and communication of facilitative conditions" by Gary L. Hermansson, Alan C. Webster and Ken McFarland (Journal of Counseling Psychology, 1988[Apr], Vol 35[2], 149-153). The date of receipt indicated for the revision of this article was incorrect. The correct date of receipt is provided in the erratum. (The following abstract of the original article appeared in record 1988-36435-001.) This experimental study examined the relation between counselor deliberate postural lean and the communication of intensity, empathic understanding, respect, and genuineness. Results, from 12 male counselors acting as their own controls under three postural lean conditions (forward, backward, and choice) in counseling interaction with female clients, suggested compensatory processes in operation. Making a required lean forward was associated with decreased facilitative levels and backward with increased levels. The latter effects were more marked, with significant differences in intensity and respect. The effects were also more marked with those counselors who, as revealed in their choice session, preferred to move forward rather than backward, with these counselors also being the most effective as assessed by communicated empathy levels. It was concluded that for effective counselors in particular, deliberate postural lean results in a subtle maintenance of an equilibrium of verbal–nonverbal communication behaviors judged as most appropriate to the moment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
29.
Five studies examined how self-focused attention affects the impact of negative moods on autobiographical memory. It was proposed that self-focused attention to moods may increase the likelihood of both mood-congruent recall and mood-incongruent recall and that the type of recall effect that occurs will depend on the manner in which people focus on their moods. In these studies, participants were led to experience negative or neutral moods, exposed to a manipulation designed to affect some aspect of their attention to their moods, and then asked to report memories. This research revealed that when people adopt a reflective orientation to their moods, they are more likely to engage in mood-incongruent recall; in contrast, when they adopt a ruminative orientation to their moods, they are more likely to engage in mood-congruent recall. Thus, the way in which people focus on their moods moderates the relation between mood and memory.  相似文献   
30.
Much has been said about the importance of formal verification in hardware synthesis, but little has been done. Where it has been applied at all, it has only been used on simple, idealized examples. This paper describes the application of formal semantic analysis and verification to part of a working high-level synthesis system. The process revealed several significant errors in that system, errors that had previously been undetected. This experience leads to some reflections on the need for a rigorous, formal basis for hardware specification and synthesis, and on the value of formal techniques.  相似文献   
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