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排序方式: 共有334条查询结果,搜索用时 31 毫秒
31.
32.
The authors tested whether perfectionism dimensions interact with specific stress to predict depression over time. A sample of 103 current and former patients completed measures of perfectionism and depression at Time 1 and measures of stress and depression 4 months later. After controlling for Time 1 depression, self-oriented perfectionism interacted only with achievement stress to predict Time 2 depression. Socially prescribed perfectionism did not interact with achievement or social stress to predict Time 2 depression, but it did predict Time 2 depression as a main effect. The results provide support for the contention that perfectionism dimensions are involved in vulnerability to depression over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Carotenoids and tocols of corn grain determined by HPLC 总被引:6,自引:0,他引:6
Evelyn J. Weber 《Journal of the American Oil Chemists' Society》1987,64(8):1129-1134
A high performance liquid chromatographic (HPLC) procedure has been developed that permits determinationof carotenoids and
tocols in the same sample preparation of corn grain. For 15 inbreds, the total carotenoids ranged from 16 to 77 μg/g dry wt
and the total tocols from 30 to 128 μg/g dry wt. For four inbreds, total carotenoids were concentrated in the horny endosperm
(83±2%) and total tocols in the germ (77±6%). After six months storage at room temperature, the mean loss of total carotenoids
for four inbreds was 42±4%, while the tocols had a mean loss of 5%.
Presented at the AOCS meeting in Honolulu, HI in May 1986. 相似文献
34.
Rats attempt to steal food from conspecifics by approaching them from the side to wrench the food from the victims' paws, but victims dodge laterally away to protect their food. Given the pervasive necessity of obtaining food, it might be expected that the behaviors of food wrenching and dodging would be common to many animals, but this idea has not been examined. In the present study, food wrenching and dodging were compared in Long-Evans and Sprague-Dawley rats (Rattus norvegicus) and out-crossed CDF1 and inbred C57b mice (Mus musculus). Mice stole food using a strategy very similar to that of rats, but they did not dodge in an open field test and dodged less in a home cage test and ran away or fought more than rats. There were no strain differences in rats, but C57b mice dodged less than CDF1 mice. Given that dodging is a component not only of food defensive behavior but also of play, sexual, and aggressive behavior, the species and strain difference may be a marker (or a key element) of changes in social behaviors that have occurred since the evolutionary separation of rats and mice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
The deterrent impact of Ontario's 12-hour licence suspension law, a law intended to mete out swift punishment is evaluated. A process model of deterrence is included. Time series analyses of the monthly log odds of number of positive B.A.C. fatalities over the number of negative B.A.C. fatalities indicated a small, short-term effect. The intermediate measures of four surveys of media coverage, Toronto residents, Ontario residents, and police forces supported these results, and affirmed the potential validity of the process model of deterrence. The results suggest that laws to increase the celerity and certainty of punishment will have little deterrent impact without enforcement and publicity of the new laws. 相似文献
36.
Winged bean lipoxygenase (linoleate: oxygen oxidoreductase EC 1.13.11.12) isoenzymes FI and FII were isolated and purified according to the method of Truong et al. (1980).FI and FII were both highly specific for linoleic acid. They exhibited optimal activity at pH 6·0 and 5·8, respectively at 30°C. An activation energy of 4·5 kcal mol?1 was calculated for this lipoxygenase within the temperature range of 30–50°C.At 0·075% Tween 20, FI and FII had Km values for linoleic acid of 0·44 and 0·37 × 10?3M, respectively, compared to 0·4 × 10?3M for the crude enzyme. Maximal activity was obtained at 1·6 × 10?3M. Higher levels of Tween 20 inhibited the lipoxygenase activity.Both isoenzymes had identical average molecular weight of 80 000 daltons by gel filtration and SDS gel electrophoresis.FI and FII isoenzymes were strongly inhibited by Hg++, Mn++, Mg++ and Fe+++ and activated by Zn++, Co++ and Fe++. A difference in the degree of inhibition or activation was observed between FI and FII response. Ca++ inhibited both FI and FII but the former was more sensitive to Ca++. KCN also inhibited the two isoenzymes.Among the antioxidants tested, butylated hydroxytoluene and butylated hydroxyanisole most effectively inhibited both FI and FII at only 10?6M. Sulphydryl reagents such as iodoacetamide and dithiothreitol have little effect on the lipoxygenase isoenzyme activity.The lipoxygenase isoenzymes were more stable at neutral pH. The enzyme in the crude extract and especially in situ was more stable to heat treatment. 相似文献
37.
Effects of fatty acid concentration and positional specificity on maize triglyceride structure 总被引:1,自引:0,他引:1
The effects of fatty acid concentration and positional specificity on maize triglyceride structure were evaluated from the
stereospecific analyses of triglycerides from 12 genotypes. The fatty acids at each position were influenced by the fatty
acid concentration in the total triglyceride except for the saturates in the 2 position. The fatty acid concentration had
the greatest effect on the fatty acid composition of position 3. The existence of positional specificity was evident from
the nonrandom distribution of the fatty acids among the three positions of the triglycerides. The concentration and positional
specificity effects could be separated in selected genotypes and their crosses. This indicated different genetic controls
for each effect. 相似文献
38.
Vingilis E McLeod AI Seeley J Mann RE Beirness D Compton CP 《Accident; analysis and prevention》2005,37(3):549-556
PURPOSE: On 1 May 1996, Ontario, Canada amended the Liquor Licence Act to extend the hours of alcohol sales and service in licensed establishments from 1 to 2 a.m. The purpose of this study was to evaluate the road safety impact of extended drinking hours in Ontario. METHOD: A quasi-experimental design using interrupted time series with a nonequivalent no-intervention control group was used to assess changes. The analyzed data sets are total and alcohol-related, monthly, traffic fatalities for Ontario, for the 11-12 p.m., 12-1 a.m., 1-2 a.m. and 2-3 a.m. time windows, for Sunday through Wednesday nights and for Thursday through Saturday nights, for 4 years pre- and 3 years post-policy change, compared to neighbouring regions of New York and Michigan. RESULTS: The blood alcohol concentration positive driver fatality trends reflected downward trends for Sunday-Wednesday 12-2 a.m. and Thursday-Saturday 1-2 a.m. for Ontario and downward trends for Thursday-Saturday 12-1 a.m. and 2-3 a.m. for New York and Michigan after the extended drinking hour policy change. Ontario total fatality data showed similar trends to the Ontario blood alcohol positive trends. CONCLUSIONS: The multiple datasets converge in suggesting little impact on BAC positive fatalities with extension of the closing hours. These observations are consistent with other studies of small changes in alcohol availability. 相似文献
39.
30 schizophrenic patients and 30 psychiatric aides were required in 4 experimental tasks to change their responses to meet changing conditions. It was hypothesized that (a) schizophrenic patients are more likely than normals to continue a response after it becomes ineffective; (b) the persistence of the maladaptive response is a function of the severity of schizophrenia. As predicted, the patients persisted longer than the aides in the first learned but later maladaptive responses, and there was some evidence that degree of resistance to change was related to the severity of schizophrenia in the patient. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Kim EY Gronewold C Chatterjee A von der Lieth CW Kliem C Schmauser B Wiessler M Frei E 《Chembiochem : a European journal of chemical biology》2005,6(2):422-431
With the aim of establishing a versatile and easy synthesis of branched saccharides for biological applications, we used molecular-dynamics simulations to model Lewis(y) to two classes of di- or triantennary saccharide mimetics. One set of mimetics was based on 1,3,5-tris(hydroxymethyl)cyclohexane (TMC) as the core, the other on furan, and both were derivatised with galactose and/or fucose. The TMC-based saccharides were biotinylated, while the furan disaccharides were treated with maleimide-activated biotin in a Diels-Alder fashion to yield oxazatricyclodecanes (OTDs). These were then assayed as cell-surface labels in human colon (SW480 and CaCo-2), liver (PLC), Glia (U333 CG 343) and ovary (SKOV-3) tumour cell lines. Discrete staining patterns were observed in all cells, usually at one or two poles of the cells, particularly with the asymmetric 3-beta-L-fucopyranosyloxymethyl-4-beta-D-galactopyranosyloxymethyl-OTD. Normal SV40-transformed fibroblasts (SV80) showed no staining. Adhesion of the highly metastatic mouse melanoma line B16 F10 to fibronectin was inhibited by 80 % by the TMC-digalactoside and by 30 % by 3,4-bis-(beta-D-galactopyranosyloxymethyl)furan. None of the saccharide mimetics inhibited the adhesion of the less metastatic B16 F1 line. Migration of B16 F10 cells through Matrigel was greatly inhibited by the TMC-digalactoside and weakly inhibited by the TMC-trigalactoside. The saccharide mimetics that had shown the best structural agreements with the terminal saccharides of Lewis(y) in the molecular dynamics simulation were also the most biologically potent compounds; this underlines the predictive nature of molecular dynamics simulations. The use of the non-saccharide cores enabled us to adapt spacer lengths and terminal saccharides to optimise the structures to bind more avidly to cell-surface lectins. 相似文献