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991.
The authors investigated genetic variation and covariation among the original Minnesota Multiphasic Personality Inventory clinical and validity scales and the restructured clinical scales. Variation in most of these scales was best explained by a combination of moderate genetic influences and environmental influences not shared by cotwins. Genetic correlations among the standard clinical scales were generally substantial and positive (M = .48), whereas genetic correlations between the clinical scales and the K scale were strong and negative. The restructured clinical scales were strongly correlated with the general Demoralization scale (M = .55), with lower genetic correlations among the remaining scales (M = .39). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
993.
In three experiments, we investigated how associative word-word priming effects in German depend on different types of syntactic context in which the related words are embedded. The associative relation always concerned a verb as prime and a noun as target. Prime word and target word were embedded in visually presented strings of words that formed either a correct sentence, a scrambled list of words, or a sentence in which the target noun and the preceding definite article disagreed in syntactic gender. In contrast to previous studies (O'Seaghdha, 1989; Simpson, Peterson, Casteel, & Burgess, 1989), associative priming effects were not only obtained in correct sentences but also in scrambled word lists. Associative priming, however, was not obtained when the definite article and the target noun disagreed in syntactic gender. The latter finding suggests that a rather local violation of syntactic coherence reduces or eliminates word-word priming effects. The results are discussed in the context of related work on the effect of gender dis-/agreement between a syntactic context and a target noun.  相似文献   
994.
995.
Students identified by talent search programs were studied to determine whether spatial ability could uncover math-science promise. In Phase 1, interests and values of intellectually talented adolescents (617 boys, 443 girls) were compared with those of top math-science graduate students (368 men, 346 women) as a function of their standing on spatial visualization to assess their potential fit with math-science careers. In Phase 2, 5-year longitudinal analyses revealed that spatial ability coalesces with a constellation of personal preferences indicative of fit for pursuing scientific careers and adds incremental validity beyond preferences in predicting math-science criteria. In Phase 3, data from participants with Scholastic Aptitude Test (SAT) scores were analyzed longitudinally, and a salient math-science constellation again emerged (with which spatial ability and SAT-Math were consistently positively correlated and SAT-Verbal was negatively correlated). Results across the 3 phases triangulate to suggest that adding spatial ability to talent search identification procedures (currently restricted to mathematical and verbal ability) could uncover a neglected pool of math-science talent and holds promise for refining our understanding of intellectually talented youth. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
This essay is a speculation of the impact of the next generation technological platform — the internetwork computing architecture (InterNCA) — on systems development. The impact will be deep and pervasive and more substantial than when computing migrated from closed computer rooms to ubiquitous personal computers and flexible client-server solutions. Initially, by drawing upon the notion of a technological frame, the InterNCA, and how it differs from earlier technological frames, is examined. Thereafter, a number of hypotheses are postulated with regard to how the architecture will affect systems development content, scope, organization and processes. Finally, some suggestions for where the information systems research community should focus its efforts (if the call for relevance is not to be taken lightly) are proposed.  相似文献   
997.
OBJECTIVE: The performance of coronary bypass grafts can be affected by a variety of circulating cell types. The initial event in any biological effect of such cells is adherence to the vascular endothelium prior to migration into the perivascular space. We aimed to investigate the expression of molecules that regulate cell adhesion in blood vessels employed as bypass conduits. METHODS: Segments of human saphenous vein, internal mammary artery, gastroepiploic artery and inferior epigastric artery were stained using specific monoclonal antibodies against the endothelial workers EN-4, Pal-E, von Willebrand factor small (vWF), and the cell adhesion molecules platelet-endothelium cell adhesion molecule (PECAM), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, the leucocyte marker (CD45) and major histocompatibility complex (MHC) class I and II antigens, with visualisation by ABC immunoperoxidase method. RESULTS: All vessels had a strong expression of the endothelial specific antigens EN4, vWF, and PECAM as well as MHC class I. However, there was less expression of Pal-E, ICAM-1, E-Selectin and of the DR determinant of MHC class II. VCAM-1, DP and DQ determinants of MHC class II were expressed to a weaker extent. There were no marked differences in the expression of all the molecules examined between the four vessel types. CONCLUSION: Thus vessels used as bypass grafts are immunogenic and possess the potential to attract and interact with blood elements. Definition of the molecules responsible could offer opportunities for modulating the response to such interactions.  相似文献   
998.
N. M. Ruis  J. K. Rose  F. H. Valone 《Lipids》1991,26(12):1060-1064
Platelet-activating factor (PAF) is a low molecular weight phospholipid which enhances human monocyte cytotoxicity for tumor cells. In the current studies, the capacity of PAF to stimulate release of tumor necrosis factor α (TNFα) by human monocytes was assessed. PAF induced maximal TNFα synthesis 2–3 hr after monocyte stimulation as assessed by dot blotting of cell-associated TNFα using polyclonal anti-TNF antibody. Maximal net release of TNFα occurred 5–16 hr after monocyte stimulation, as assessed by a specific ELISA. Dose-response studies revealed that a maximal two- to three-fold increase in release of TNFα occurs at 10–100 pM PAF. LysoPAF and the optical isomer of PAF did not stimulate release of TNFα, suggesting that stimulation is mediated by specific PAF receptors. Scatchard analysis of [3H]PAF binding to monocyte membranes revealed 651±495 binding sites/monocyte with a Kd of 4.7±4.2×10−10M. PAF is a structurally unique activator of monocytes whose interactions with TNFα and other cytokines may be critical to host defense against tumors. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989.  相似文献   
999.
In 3 experiments, a pronunciation task was used to examine repetition priming of novel nonwords in young and older adults. The contributions of item and associative priming to the total repetition priming effect were assessed. In Experiment 1, age consistency was found in both components of repetition priming after 9 repetitions of nonwords. Experiment 2 established that young and older adults were similar in item and associative priming after as few as 2 repetitions of nonwords. Finally, Experiment 3 demonstrated that associative priming persists for at least 3 min and that it is dissociable from cued recall. The overall pattern of results strongly argues that elaborative processing is not necessary to obtain associative priming in indirect memory tasks and that young and older adults show similar magnitudes of associative priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
We report three cases of leg ulcers complicating cryoglobulinaemia which resisted conventional therapy but responded to interferon-2 alpha. All three cases improved with the complete resolution of painful vasculitic lesions and healing of deep ulcers. The dose of interferon to produce ulcer healing was determined by individual response with escalation of the daily dose to 4.5 x 10(6) units per day required in one case. A lower dose of maintenance interferon could be used to prevent subsequent relapses of disease.  相似文献   
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