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871.
The influence of low levels of protein and vitamin A on indicators of the immune response was assayed in rats. The levels of protein and vitamin A intake of the Cuban population affected by epidemic neuropathy in 1993 was reproduced in 4 diets: control, protein deficiency (DP), vitamin A deficiency (DA), protein and vitamin A deficiency (DAP). The Peyer's patches evaluated the Interleukin 1 expression gene and was related with corporal weight, food intake, serum protein, vitamin A, immunology indicators and histology evaluation (spleen, thymus and liver). Protein deficiency generated a significant decrease of the expression gene of Interleukin 1. Atrophy signs in lymphoid tissues and morphologic changes in the liver were associated with the dietary protein utilization. Protein and vitamin A deficiency generated significant stimulation of the Interleukin 1 expression gene with increase of the level of the inflammatory state indicators as serum alpha protein, total complement and neutrophils. This stimulation could be generated by a deficient retinol mobilization to tissues. These results support the hypothesis of the function of cytokines as mediators of subclinical symptoms of the immune system during the nutritional affectations.  相似文献   
872.
A statistical method for predicting automobile driving posture   总被引:2,自引:0,他引:2  
A new model for predicting automobile driving posture is presented. The model, based on data from a study of 68 men and women in 18 vehicle package and seat conditions, is designed for use in posturing the human figure models that are increasingly used for vehicle interior design. The model uses a series of independent regression models, coupled with data-guided inverse kinematics, to fit a whole-body linkage. An important characteristic of the new model is that it places greatest importance on prediction accuracy for the body locations that are most important for vehicle interior design: eye location and hip location. The model predictions were compared with the driving postures of 120 men and women in five vehicles. Errors in mean eye location predictions in the vehicles were typically less than 10 mm. Prediction errors were largely independent of anthropometric variables and vehicle layout. Although the average posture of a group of people can be predicted accurately, individuals' postures cannot be predicted precisely because of interindividual posture variance that is unrelated to key anthropometric variables. The posture prediction models developed in this research can be applied to posturing computer-rendered human models to improve the accuracy of ergonomic assessments of vehicle interiors.  相似文献   
873.
To investigate the relationship between classroom behavior patterns and academic achievement, multiple regression procedures were carried out in which the frequencies of 12 behaviors were used to predict the achievement scores of 90 2nd graders. Ss, with an average IQ of 98.69, were observed for 5-min periods on each of 4 days during language arts in the fall of the school year and again in the spring. The final multiple R between fall behavior patterns and fall achievement was .63, and that between spring behavior patterns and spring achievement was .51. The final multiple R for predicting spring achievement from fall behavior was .60. Of particular interest was the finding that the predictive value of combinations of discrete behaviors compared favorably to that obtained from IQ tests (r = .70), and that the addition of behavioral information to test information provided a more accurate prediction of achievement over the school year than that obtained by either alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
874.
Major vault protein (MVP), also called lung resistance-related protein is a ribonucleoprotein comprising a major part (>70%) of the vault particle. The function of vault particle is not known, although it appears to be involved in multi-drug resistance and cellular signaling. Here we show that MVP is expressed in mammalian, porcine, and human ova and in the porcine preimplantation embryo. MVP was identified by matrix-assisted laser-desorption ionization-time-of-flight (MALDI-TOF) peptide sequencing and Western blotting as a protein accumulating in porcine zygotes cultured in the presence of specific proteasomal inhibitor MG132. MVP also accumulated in poor-quality human oocytes donated by infertile couples and porcine embryos that failed to develop normally after in vitro fertilization or somatic cell nuclear transfer. Normal porcine oocytes and embryos at various stages of preimplantation development showed mostly cytoplasmic labeling, with increased accumulation of vault particles around large cytoplasmic lipid inclusions and membrane vesicles. Occasionally, MVP was associated with the nuclear envelope and nucleolus precursor bodies. Nucleotide sequences with a high degree of homology to human MVP gene sequence were identified in porcine oocyte and endometrial cell cDNA libraries. We interpret these data as the evidence for the expression and ubiquitin-proteasome-dependent turnover of MVP in the mammalian ovum. Similar to carcinoma cells, MVP could fulfill a cell-protecting function during early embryonic development.  相似文献   
875.
Samples of ambient organic films deposited on exterior window surfaces from lower Manhattan and Brooklyn in New York City were collected six weeks after the terrorist attacks at the World Trade Center (WTC) on September 11, 2001 and analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Total tetra- through octa-CDD/F concentrations in window films within 1 km of the WTC site in lower Manhattan ranged up to 630,000 pg/m2 (estimated as a mass concentration of ca. 1,300,000 pg/ g) and a maximum toxic equivalent (TEQ) concentration of 4700 TEQ/m2 (ca. 10 000 pg TEQ/g). Measurements at a background site 3.5 km away in Brooklyn showed lower concentrations at 130 pg TEQ/m2 (260 pg TEQ/g). Ambient gas-phase PCDD/F concentrations estimated for each site using an equilibrium partitioning model suggested concentrations ranging from ca. 2700 fg-TEQ/m3 near the WTC site to the more typical urban concentration of 20 fg-TEQ/m3 atthe Brooklyn site. Multivariate analyses of 2,3,7,8-substitued congeners and homologue group profiles suggested unique patterns in films near the WTC site compared to that observed at background sites in the study area and in other literature-derived combustion source profiles. Homologue profiles near the WTC site were dominated by tetra-, penta-, and Hexa-CDD/Fs, and 2,3,7,8-substituted profiles contained mostly octa- and hexachlorinated congeners. In comparison, profiles in Brooklyn and near mid-Manhattan exhibited congener and homologue patterns comprised mainly of hepta- and octa-CDDs, similar to that commonly reported in background air and soil.  相似文献   
876.
877.
The behavioral and subjective effects of acute oral doses of placebo, ethanol (0.5, 1.0, and 2.0 g/kg), and pentobarbital (150, 300, 600, and 750 mg/70 kg) were compared in 8 male volunteers with histories of sedative drug abuse using a double-blind, double-dummy, cross-over design. Ethanol and pentobarbital produced similar dose-related decrements in psychomotor and cognitive performance and exhibited a similar profile of effects on staff- and participant-rated measures. There was some evidence indicating that, at the highest dose, pentobarbital was perceived by participants as being more sedating than ethanol and that pentobarbital has a greater abuse liability than ethanol. In conjunction with the results of previous human laboratory studies comparing the effects of different types of sedative-hypnotic drugs, these results support a mostly barbituratelike rather than benzodiazepinelike profile of effects for ethanol. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
878.
Two studies with 59 Ss (preschoolers–4th graders) explored the effects of stimulus factors on children's ability to monitor comprehension of messages as listeners in a referential communication situation. Results of Exp I show that both complexity of the stimulus array and degree of message ambiguity affected performances. In line with previous findings, 4th graders but not younger Ss showed evidence of effective comprehension monitoring. Data from Exp II show that when conducive stimulus conditions were arranged, even 1st graders demonstrated considerable skill in comprehension monitoring. In addition to investigating comprehension monitoring per se, the studies also examined the role of comprehension monitoring in directing the overall comprehension process. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
879.
880.
[Correction Notice: An erratum for this article was reported in Vol 15(5) of Journal of Experimental Psychology: Learning, Memory, and Cognition (see record 2008-10689-001). On page 157, parts of two sentences in the Results and Discussion section were omitted. The corrected sentences are provided in the erratum.] Three experiments examined transfer between 2 isomorphic subdomains of algebra and physics. The two areas were arithmetic-progression problems in algebra and constant-acceleration problems in physics. High school and college students who had learned one of these subtopics were presented with word problems that used either content from the domain they had originally studied or content based on the unfamiliar but analogous domain. Ss who had learned arithmetic progressions were very likely to spontaneously recognize that physics problems involving velocity and distance can be addressed using the same equations. Analysis of problem-solving protocols revealed that the recognition was immediate and that the solutions were a straightforward application of the algebraic method. Such recognition occurred even when the algebraic procedures were taught using example word problems all of which were drawn from a single content area (e.g., "money" problems). In contrast, Ss who had learned the physics topic almost never exhibited any detectable transfer to the isomorphic algebra problems. The results were interpreted in terms of content-free vs content-specific applicability conditions for mathematical procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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