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31.
32.
To extend R. E. Fancher's (see record 1987-31600-001) review of claims that photographs of the Kallikak family in H. H. Goddard's (1912) study had been retouched to make them look more menacing and retarded, 29 Ss (aged 18–69 yrs) were surveyed for their impressions of the photographs. Overall, Ss were strongly inclined to view the photographed individuals as "kind" and "very bright." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
G. Oladunni Taylor John J. Albers G. Russell Warnick Janet L. Adolphson H. McFariane D. R. Sullivan C. E. West V. Sri-Hari R. Edwards 《Lipids》1987,22(3):173-177
The high mortality rate from coronary heart disease (CHD) among Indians compared to Negroes in Trinidad led us to test plasma
lipid profiles to see whether dietary or genetic factors might be involved. There were no interracial differences in the composition
of plasma cholesterol ester fatty acids of the tested women and neonates. This finding suggests that dietary fat does not
account for the interracial difference in CHD, nor does the cause appear to be due to genetic differences in lipid profiles,
as there was no significant difference between values for plasma triglycerides, total cholesterol, high density lipoprotein
(HDL) cholesterol, apo-I, apo-II, apo B or cholesterol ester fatty acids in the cord blood of each racial group.
Blood samples were collected from 69 nonpregnant and 71 postpartum, fasted Negro and Indian women. Also taken were 71 umbilical
cord blood samples. The mean triglyceride level was significantly lower in the Negro nonpregnant and postpartum women than
in the Indians. HDL cholesterol and apo-I values were lower in the Indian women. There were no significant differences in
the total cholesterol and apo B measurements. The triglyceride values for postpartum women were higher than those of the nonpregnant
Negroes and Indians (75% and 47%, respectively), whereas the total cholesterol and HDL cholesterol, apo A-I and apo A-II ranged
from 9% to 29% higher in the postpartum women. Apo B was about 40% higher postpartum in both ethnic groups.
The high CHD rate of Indians in Trinidad cannot be explained by dietary factors, plasma total cholesterol or fatty acid composition.
However, the lower level of HDL cholesterol and plasma A-I could play a role in the higher CHD rate in Indians. 相似文献
34.
Fiber Coating Concepts for Brittle-Matrix Composites 总被引:4,自引:0,他引:4
Janet B. Davis Jan P. A. Löfvander Anthony G. Evans Ewald Bischoff Mario L. Emiliani 《Journal of the American Ceramic Society》1993,76(5):1249-1257
The current interest in tough, high-temperature materials has motivated fiber coating development for brittle-matrix composites with brittle reinforcements. Such coatings are needed for controlled interface debonding and frictional sliding. The system investigated in this study was sapphire fiber-reinforced alumina. This system is thermochemically stable for severe use conditions, exhibits little thermal expansion mismatch, and utilizes the excellent strength and creep resistance of sapphire reinforcements. Porous oxide and refractory metal coatings which satisfy requirements for toughness improvement in these composites were identified by employing a variety of newly developed mechanical testing techniques for determining the interfacial fracture energies and sliding resistances. 相似文献
35.
A study of structural determinants in the interleukin-1 fold 总被引:1,自引:0,他引:1
Swindells Mark B.; Thornton Janet M. 《Protein engineering, design & selection : PEDS》1993,6(7):711-715
The structures of interleukin-1ß, basic fibroblastgrowth factor and Erythrina trypsin inhibitor have been analysedin order to determine whether the hydrophobic core remains conserved,even when the structures have extremely low sequence similarities.We find that there are significant differences in the way eachprotein achieves a satisfactory arrangement of core residuesand that positions which contribute to the core of one structureare not guaranteed to contribute to the integrity of another.Furthermore, the side-chain packing arrangements of these coreresidues vary significantly between the three structures. Duringthis analysis the side-chain rotamers for three independentlydetermined interleukin-1ß structures were also compared.It was found that although buried residues are generally inagreement the remaining residues frequently occupy differentrotamers in the three structures. This suggests that althoughmeaningful studies are possible for buried side-chains the resultsobtained from equivalent analyses of accessible residues shouldbe treated with caution. These results are discussed with specificreference to the optimization of side-chain packing in proteinsof known structure. 相似文献
36.
E-ARK (European Archiving of Records and Knowledge Preservation) is currently introducing standardization, new tools, and infrastructure into pan-European digital archival systems. The results of this pilot project can be applied to higher education where research data centers are required to preserve data for re-use in accordance with new open policies.We elucidate how the E-ARK best practice survey has informed the development of new information packages for ingest, preservation, and re-use, and show how these can be applied to the Arts, Humanities, and Social Sciences with practical exemplars such as census data. 相似文献
37.
Dihydrofolate reductase (DHFR) has been a well-recognized target for the development of therapeutics for human cancers for several decades. Classical inhibitors of DHFR use an active transport mechanism to gain access to the cell; disabling this mechanism creates a pathway for resistance. In response, recent research focuses on nonclassical lipid-soluble DHFR inhibitors that are designed to passively diffuse through the membrane. Here, a new series of propargyl-linked antifolates are investigated as potential nonclassical human DHFR inhibitors. Several of these compounds exhibit potent enzyme inhibition with 50% inhibition concentration values under 500 nM. Molecular docking investigations show that the compounds maintain conserved hydrogen bonds between the pyrimidine ring and the enzyme as well as form van der Waals interactions with critical residues in the active site. Interestingly, the most potent compound, 2,4-diamino-5-(3-(3,4,5-trimethoxyphenyl)prop-1-ynyl)-6-ethylpyrimidine (compound 35), is 3500-fold more potent than trimethoprim, a potent inhibitor of bacterial DHFR but weak inhibitor of human DHFR. The two structural differences between compound 35 and trimethoprim show that the propargyl linkage and the substitution at C6 of the pyrimidine ring are critical to the formation of contacts with Thr 56, Ser 59, Ile 60, Leu 22, Phe 31 and Phe 34 and hence, to enhancing potency. The propargyl-linked antifolates are efficient ligands with a high ratio of potency to the number of non-hydrogen atoms and represent a potentially fruitful avenue for future development of antineoplastic agents. 相似文献
38.
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40.
Stephen R. Okkonen Carin J. Ashjian Janet T. Clarke Kevin D. Taylor 《Remote sensing of environment》2011,115(8):2168-2174
Satellite images, along with oceanographic, meteorological, and whale aerial survey data, are used to illustrate aspects of ocean circulation associated with a bowhead whale feeding ‘hotspot’ near Barrow, Alaska. In response to weak winds, a strong front forms near the shelf-break along the southern edge of Barrow Canyon when the Alaska Coastal Current flows adjacent to the southern flank of Barrow Canyon or intrudes onto the western Beaufort shelf. This front is of particular local interest because it is indicative of aggregation and retention of zooplankton on the western Beaufort shelf and, as a result, is a locus for bowhead whales pausing to feed during their westward fall migration. Groups (4 or more individuals) of bowhead whales are primarily seen on the western Beaufort shelf following wind conditions that promote the formation of this front. 相似文献