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991.
D. Santillo A. Fernandes R. Stringer R. Alcock M. Rose S. White K. Jones P. Johnston 《Food Additives & Contaminants》2003,20(3):281-290
The potential for use of butter as a widely available, relatively uniform lipid-rich matrix for the determination of spatial distributions of persistent organic pollutants has already been demonstrated. The present study determines the contributions to toxicity equivalence (TEQ) from polychlorinated dioxins and furans (PCDD/Fs) and polychlorinated biphenyls (PCBs) using butter samples from 24 countries world wide. Concentrations of PCDD/Fs and dioxin-like PCBs ranged from 0.07 to 5.69 pg ΣWHO-TEQ g -1 lipid. For most samples, PCDD/F TEQ fell within ranges reported for European dairy products over the last decade (0.3-2 pg g -1 lipid I-TEQ), though a single sample from Spain was a notable exception. Other than this sample, the highest values were recorded for samples from the Netherlands and Italy, with those from India, China and Tunisia also being relatively high. The contribution from non- ortho -PCBs was particularly significant in samples from Germany, Austria, Italy, the Czech Republic, Tunisia, India and Argentina. Although overall TEQs were generally highest in European and Mediterranean butters, elevated levels were also apparent in industrializing regions of Asia (India, China) and Latin America (Argentina). More detailed regional studies would be necessary to identify likely dioxin and PCB sources in each case. Nevertheless, this study supports the utility of butter as a monitoring matrix that may be especially applicable in regions for which monitoring programmes are currently lacking. 相似文献
992.
Donna G. Blackmond 《Catalysis Letters》2003,89(3-4):281-284
993.
Four mid-lactation Holstein dairy cows (mean milk yield on day of experiments 26.1 kg/d) were used in a series of experiments to establish the contribution of non-insulin-mediated glucose uptake to total glucose uptake at basal insulin concentrations. A secondary objective was to determine whether somatostatin affects the action of infused insulin. In part I of the experiment a primed continuous infusion [6,6-2H]glucose (45.2 micrograms/kg per min) was begun at time 0 and continued for 5 h. After 3 h of [6,6-2H]glucose infusion (basal period) a primed continuous infusion of insulin (0.001 i.u./kg per min) was administered for 2 h. Coincidental with the insulin infusion, normal glucose was also infused in order to maintain the plasma glucose concentration at euglycaemia. Part II of the experiment was the same as part I except that somatostatin was infused for 2 h (0.333 micrograms/kg per min) instead of insulin. In part III of the experiment both insulin and somatostatin were infused for the final 2 h. Plasma insulin levels were increased by insulin infusion (to 0.1476 to 0.1290 i.u./l for parts I and III respectively) and were reduced by somatostatin infusion in part II (to 0.006 i.u./l) relative to the basal periods (mean 0.021 i.u./l). Glucose uptake during somatostatin infusion (2.50 mg/kg per min; part II) was 92.0% of that observed in the respective basal period (2.72 mg/kg per min). Circulating insulin levels were much lower than the dose of insulin that causes a half maximal effect on glucose uptake (0.06-0.10 i.u./l for ruminants); consequently insulin-mediated glucose uptake was probably absent in part II. Secondly, glucose uptake following insulin only infusion (4.05 mg/kg per min) was significantly lower than that observed when insulin plus somatostatin was infused (4.69 mg/kg per min), indicating that somatostatin either directly or indirectly enhanced the action of insulin on glucose uptake. 相似文献
994.
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
995.
996.
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
997.
998.
Webb Rose Mary; Lubinski David; Benbow Camilla Persson 《Canadian Metallurgical Quarterly》2007,99(2):397
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
999.
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
1000.
AH Chester JA Borland PM Taylor ML Rose MH Yacoub 《Canadian Metallurgical Quarterly》1996,10(8):676-683
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