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991.
Separation of cholesterol,and fatty acylglycerols,acids and amides by thin-layer chromatography 总被引:6,自引:0,他引:6
A rapid unidimensional thin-layer chromatographic (TLC) method for the separation of neutral lipids is described, using two
sequential solvent systems of different polarity. Excellent separations of mono-, di- and triglycerides, fatty acids, fatty
amides, and cholesterol are thereby achieved. Separation is accomplished at room temperature and requires 25 min.
Reference to brand of firm name does not constitute endorsement by the United States Department of Agriculture over others
of a similar nature not mentioned. 相似文献
992.
Daily repetitive transcranial magnetic stimulation (rTMS) improves mood in depression 总被引:1,自引:0,他引:1
MS George EM Wassermann WA Williams A Callahan TA Ketter P Basser M Hallett RM Post 《Canadian Metallurgical Quarterly》1995,6(14):1853-1856
Converging evidence points to hypofunction of the left prefrontal cortex in depression. Repetitive transcranial magnetic stimulation (rTMS) activates neurons near the surface of the brain. We questioned whether daily left prefrontal rTMS might improve mood in depressed subjects and report a pilot study of such treatment in six highly medication-resistant depressed inpatients. Depression scores significantly improved for the group as a whole (Hamilton Depression Scores decreased from 23.8 +/- 4.2 (s.d.) at baseline to 17.5 +/- 8.4 after treatment; t = 3.03, 5DF, p = 0.02, two-tailed paired t-test). Two subjects showed robust mood improvement which occurred progressively over the course of several weeks. In one subject, depression symptoms completely remitted for the first time in 3 years. Daily left prefrontal rTMS appears to be safe, well tolerated and may alleviate depression. 相似文献
993.
Laughter facilitates the adaptive response to stress by increasing the psychological distance from distress and by enhancing social relations. To test these hypotheses, the authors related measures of bereaved adults' laughter and smiling 6 months postloss to measures of their (a) subjective emotion and dissociation from distress, (b) social relations, and (c) responses they evoked in others. Duchenne laughter, which involves orbicularis oculi muscle action, related to self-reports of reduced anger and increased enjoyment, the dissociation of distress, better social relations, and positive responses from strangers, whereas non-Duchenne laughter did not. Lending credence to speculations in the ethological literature, Duchenne laughter correlated with different intrapersonal and interpersonal responses than Duchenne smiles. Discussion focuses on the relevance of these findings to theories of positive emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
The purpose of this study was to determine the satisfaction and fringe benefits of Texas dental hygienists and compare the data to a recent national study. A blind survey was forwarded to 5,294 active, licensed dental hygienists to obtain data for Texas. Responses were received from 2,172 dental hygienists, a 41 percent response rate. The greatest number of responses came from the larger cities in Texas: Dallas, Houston, Austin, and San Antonio. Fifty-eight percent of Texas hygienists receive paid vacation, 25 percent medical insurance, 37 percent sick pay, and 26 percent receive some type of retirement. Nationally, the figures are higher. The survey also sought to determine satisfaction levels. Most dental hygienists are satisfied with their salary (65%), their career (85%), and feel secure in their employment (92%), while only 46 percent are satisfied with benefits. The survey results are inconclusive for hygienists' in the state of Texas based on the 41 percent response rate. Practical information may assist employers in recruitment and retention of a dental hygienist into the practice. 相似文献
995.
DuPaul George J.; Power Thomas J.; Anastopoulos Arthur D.; Reid Robert; McGoey Kara E.; Ikeda Martin J. 《Canadian Metallurgical Quarterly》1997,9(4):436
Behavior rating scales are a primary method for screening and identifying children with attention deficit hyperactivity disorder (ADHD). The factorial structure and normative data of a teacher rating scale containing the 18 symptoms of ADHD were examined in this study. Factor analyses and assessment of differences in ADHD ratings across sex, age, and ethnic group were conducted with 4,009 children and adolescents who attended kindergarten through 12th grade in 31 U.S. school districts. Two factors (inattention and hyperactivity-impulsivity) were derived, and normative data for a nationally representative sample were presented. Boys, younger children, and African Americans received higher ratings of ADHD symptoms. Limitations of this investigation and potential uses of this scale in clinical practice and research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
997.
Faking and selection: Considering the use of personality from select-in and select-out perspectives.
Mueller-Hanson Rose; Heggestad Eric D.; Thornton George C. III 《Canadian Metallurgical Quarterly》2003,88(2):348
The effects of faking on criterion-related validity and the quality of selection decisions are examined in the present study by combining the control of an experiment with the realism of an applicant setting. Participants completed an achievement motivation measure in either a control group or an incentive group and then completed a performance task. With respect to validity, greater prediction error was found in the incentive condition among those with scores at the high end of the predictor distribution. When selection ratios were small, those in the incentive condition were more likely to be selected and had lower mean performance than those in the control group. Implications for using personality assessments from select-in and select-out strategies are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
Coefficient of true digestibility of refined groundnut oil in rats, fed a diet containing 4% Hawk and Oser's salt mixture which is stoichiometrically equivalent to Osborne-Mendel's salt mixture and which provides 473.4 mg calcium and 71.6 mg magnesium per 100 g diet was found to be 96.6. Corresponding figure with a similar diet but containing 2% salt mixture-351 of Hubbel et al. providing 434.2 mg calcium and 20.9 mg magnesium per 100 g diet was only 90.0. Higher digestibility of the oil with the Hawk-Oser's salt mixture was due to lesser excretion of soap (in the main) and neutral fat, compared to that obtained with the diet containing the other salt mixture. In Hawk and Oser's salt mixture, the sources of calcium are citrate, hydrogen phosphate and carbonate of calcium whereas in the other salt mixture, it is exclusively derived from calcium carbonate. It seems that source of calcium in a diet has profound effect on the digestibility of a fat. 相似文献
1000.
In this article the author responds to comments made in this issue (see records 2005-03019-010; 2005-03019-011; 2005-03019-012; 2005-03019-013; and 2005-03019-014) responding to his original article entitled Loss, trauma, and human resilience: Have we underestimated the human capacity to thrive after extremely aversive events? (see record 2004-10043-003). The author notes that in his original article he focused on three crucial points: Resilience among adults represents a distinct and empirically separable outcome trajectory from that normally associated with recovery from trauma; resilience is more prevalent than generally accepted in either the lay or professional literature; and there are multiple and sometimes unexpected factors that inform adult resilience. Owing to the brevity of the article, the author could only touch briefly on many of the more nuanced and complex issues suggested by the resilience construct; this left plenty of room for critique. Fortunately, the comments are generous and insightful and for the most part compatible with the driving goal of the article. As might be expected, of course, there were statements peppered throughout the comments that the author deemed worthy of rebuttal or correction. He considers four points that seemed to beg most urgently for response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献