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排序方式: 共有643条查询结果,搜索用时 62 毫秒
61.
Yung-Sheng Huang Dave E. Mills Ron P. Ward David F. Horrobin Valerie A. Simmons 《Lipids》1989,24(7):565-571
Weanling male spontaneously hypertensive (SHR) and normotensive (WKY) rats were maintained on a fat-free semisynthetic diet
and killed at various intervals. The effects of fat-depletion on the appearance of essential fatty acid (EFA) deficiency symptoms,
the progressive changes of major fatty acids in plasma, liver, heart, and kidney phospholipids (PL), and in skin total lipids
were compared between these two strains. After five weeks on the diet, the slower growth and the appearance of EFA deficiency
symptoms became evident in SHR. In general, fat-depletion reduced the levels of n−6 fatty acids, whereas it increased those
of 20∶3n−9. However, the fat-depletion induced reduction of 18∶2n−6 in heart PL and 20∶4n−6 in kidney, while the elevation
of 20∶3n−9 in plasma, heart, and kidney PL were greater in WKY than in SHR. As a result, the elevation of biochemical EFA
deficiency index—20∶3n−9/20∶4n−6 ratio—was greater in WKY than in SHR. In comparison with WKY, the concentrations of liver
triacylglycerols and the weights of adipose tissues in SHR were reduced to a greater extent, indicating an active catabolism
of triacylglycerols in SHR. This study suggests that the earlier appearance of morphological symptoms of EFA deficiency in
SHR was not associated with the reducing n−6 EFA levels or with an elevation of triene/tetraene ratio, but possibly to a reduced
supply of n−6 EFA for skin prostaglandin synthesis. 相似文献
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Manitoba's Rural and Northern Community-Based Training Program for Psychology Interns and Residents.
McIlwraith Robert D.; Dyck Karen G.; Holms Valerie L.; Carlson Torie E.; Prober Nancy G. 《Canadian Metallurgical Quarterly》2005,36(2):164
This article describes a unique internship training experience developed by the Department of Clinical Health Psychology of the Faculty of Medicine of the University of Manitoba. Interns live in and provide services to remote northern communities for half of the internship year and receive supervision from a psychologist in the community, supplemented by telehealth. The department also offers a full-year, postdoctoral rural residency. Ten interns and 4 residents have been trained so far. The community-based generalist training model and responses to the challenges, for both supervisors and trainees, of working in small underserved communities are described. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Valerie J. Paul Mark M. Littler Diane S. Littler William Fenical 《Journal of chemical ecology》1987,13(5):1171-1185
Results of field feeding preference studies with 12 species of tropical green algae of the genusCaulerpa showed thatC. ashmeadii was preferred least by herbivorous fishes. Chemical investigations ofC. ashmeadii demonstrated the presence of high concentrations of sesquiterpenoid metabolites. The chemical isolation and structural elucidation of five majorC. ashmeadii metabolites, as well as the results of field feeding preference, antimicrobial, and ichthyotoxicity assays demonstrating the biological activities of these metabolites are reported here. 相似文献
69.
Examined the extent to which the 36 items of the Rokeach Value Survey (RVS) provide comprehensive and representative coverage of the value domain in 2 experiments. In Exp I, intensive semistructured interviews, based on the RVS, were conducted with 73 adults drawn from an electoral roll. Test–retest reliabilities were examined over 4 wks with 208 university students. In Exp II, factor structure was explored with 483 adults from the general population and with 688 university students. All Ss completed inventories of goal values, mode values, and social values. Data provide qualified support for the comprehensiveness of the instrument. The major weaknesses in sampling involved the facets of physical well-being and individual rights. Other areas not represented were thriftiness and carefreeness. The need for multi-item indices for value constructs is discussed, as are the advantages of a rating procedure over a ranking procedure from both psychometric and empirically valid perspective. An alternative instrument based on the work of Rokeach is proposed. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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