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81.
It is proposed that advertising research be based less on one-way transmission models of communication and more on multivariate studies with emphasis on receivers' contributions to communication outcomes. A four-level model of the process is presented and several dimensions within each level are identified, based upon recent research on TV commercial effects. The four levels described are (1) the unconscious level, (2) the immediate perceptual level, (3) the retention or learning level, and (4) the behavior level. Research at each level is discussed. 相似文献
82.
FA Amosenko VV Surkov TI Tikhonenko TS Maksimova 《Canadian Metallurgical Quarterly》1976,26(3):361-366
Progressive systemic sclerosis may be associated with focal myocardial fibrosis. Electrocardiographic abnormalities including conduction block are common in progressive systemic sclerosis but whether they are due to direct destruction of the specialized conduction tissue of the heart is uncertain. The conduction systems of 35 patients with progressive systemic sclerosis were studied. Of these 35 patients, 17 (50 per cent) had myocardial fibrosis of the type seen in progressive systemic sclerosis. In 10 of the 17, it was severe. Sinus node fibrosis was present in 13 patients and was nearly as frequent in those with as in those without the progressive systemic sclerosis myocardial lesion. Overlying pericarditis may have contributed to the fibrotic changes within the sinoatrial nodes in seven of the 13 patients. The atrioventricular node and main His bundles were normal. However, fibrotic changes were found in the proximal bundle systems in six patients. In three of the six, severe myocardial progressive systemic sclerosis was present, two had focal fibrous atrophy of the left bundle, and one had complete interruption of the right bundle. In only the latter patient was this reflected in the electrocardiogram which showed a right bundle branch block. Three patients without progressive systemic sclerosis myocardial lesions also had fibrous atrophy of a portion of the proximal left bundle branch, and in one the electrocardiogram showed an isolated left anterior hemiblock. Thus, morphologic abnormalities within the conduction system in our patients are difficult to attribute to progressive systemic sclerosis per se. Furthermore, although conduction abnormalities were more frequent in patients with myocardial disease, specific conduction system disease was not the cause in most patients. As has been noted in ischemic heart disease, the conduction system appears to be relatively spared from the myocardial changes of progressive systemic sclerosis, and the high incidence of conduction disturbances in this condition may be a consequence, rather, of damage to working myocardium. 相似文献
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84.
We measured the effect of a common baby food, strained pears, on the absorption of iron from human milk. Five adult subjects were initially fed 1 dL of human milk that contained added ferrous citrate Fe 59; the same subjects were later fed human milk and one jar of baby food. Incorporation of 59Fe into RBCs averaged approximately one quarter of the administered iron from the human milk. When the milk was combined with the baby food, incorporation was significantly decreased. The addition of a supplemental food to the diet of the breast-fed infant impairs the bioavailability of the iron from human milk. 相似文献
85.
86.
Simoni Jane M.; Pantalone David W.; Plummer Mary D.; Huang Bu 《Canadian Metallurgical Quarterly》2007,26(4):488
Objective: To determine the efficacy of a peer-led social support intervention involving support groups and telephone contacts compared with standard clinical care to enhance antiretroviral medication adherence. Design: Randomized controlled trial with follow-up. Participants were 136 HIV-positive indigent mainly African American and Puerto Rican men and women recruited from an outpatient clinic in the Bronx, New York. The 3-month intervention was delivered by other HIV-positive clinic patients trained in addressing barriers to adherence and sensitively providing appraisal, spiritual, emotional, and informational adherence-related social support. Main outcome measures: Medical chart-abstracted HIV-1 RNA viral load, antiretroviral adherence according to electronic drug monitoring and participant self-report, and social support and depressive symptomatology. All assessments conducted at baseline, 3 months, and 6 months. Results: Intent-to-treat and as-treated analyses indicated no between-conditions intervention effects on the primary outcome of HIV-1 RNA viral load or any of the secondary outcomes at immediate postintervention or follow-up. Post hoc analyses within the intervention condition indicated greater intervention exposure was associated with higher self-reported adherence, higher social support, and lower depressive symptomatology at follow-up, even after controlling for baseline adherence. Conclusion: Null findings, consistent with the limited literature on efficacious highly active antiretroviral therapy (HAART) adherence interventions, may be due to insufficient exposure to the intervention, its low intensity, or the nature of the sample-a heterogeneous HAART-experienced group of patients with high levels of substance use and multiple other competing stressors. Overall, findings highlight the need for more comprehensive and intensive efforts to battle nonadherence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
The electrical contact resistance between isolated pairs of micron-sized gold particles has been measured as a function of
their separation using apparatus constructed in house. When incorporated into a percolation model for current transport in
a conducting particle filled insulator, the results of such measurements have been shown to be consistent with the observed
variation of conductivity with filler content beyond the percolation threshold in gold filled epoxies. This has been tested
further by using adsorbed alkanethiol monolayers to control the interparticle spacing in the composites, demonstrating the
importance of the contact resistance for the macroscopic current transport properties.
Received: 22 September 1997/Revised version: 30 October 1997/Accepted: 31 October 1997 相似文献
88.
C. Houphouët-Boigny C.J.G. Plummer M.D. Wakeman J.-A.E. Månson 《Polymer Engineering and Science》2007,47(7):1122-1132
The present work is aimed at assessing the feasibility of integrating thermoplastic polypropylene nanocomposite matrices into conventional fiber-reinforced composites based on hybrid textiles that incorporate both the matrix and glass-fiber yarns, in order to reduce impregnation times. The focus is on the preparation and properties of the polypropylene nanocomposite fiber precursors and the implications for composite processing in general. However, preliminary results are also given that demonstrate satisfactory impregnation and consolidation of simple textiles produced byco-weaving the nanocomposite yarns with glass-fibers, given suitable processing conditions. POLYM. ENG. SCI., 47:1122–1132, 2007. © 2007 Society of Plastics Engineers 相似文献
89.
90.