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31.
AIM: To determine whether Helicobacter pylori releases cysteamine into gastric juice as cysteamine is known to be ulcerogenic. METHODS: Samples of fasting gastric juice were collected from 22 individuals (four women); 10 subjects were H pylori negative. The presence of infection was confirmed by examination and culture of gastric biopsies. Cysteamine in gastric juice was measured by reversed phase gradient high performance liquid chromatography with a detection limit of 10 mumol/l. RESULTS: Cysteamine was not detected in any of the gastric juice samples or in extracts of cultured H pylori. CONCLUSIONS: If H pylori produces cysteamine then the amounts produced are insignificant and are unlikely to explain the association between H pylori infection and the development of duodenal ulcer disease. 相似文献
32.
Results of measurements of thermal expansion of Portland cement paste, mortar, concrete and a dolomitic rock aggregate are presented. Test temperatures ranged from 27 to 871°C. Cement paste contracted when subjected to temperatures from 204 to 871°C. Thermal expansion of mortar and concrete was dominated by thermal expansion characteristics of the mineral aggregate. However, expansion was moderated by contraction of the cement paste matrix at elevated temperatures. Average coefficients of expansion, over specific temperature ranges, are given for the materials tested. Equipment developed to control automatically the rate of heating and record strain vs. temperature relationships is described. 相似文献
33.
Each of 72 professional personnel consultants rated the suitability of 1 bogus applicant for selected masculine, feminine, and neuter jobs, and for alternatives to employment. Each resumé was identical with the exception of the systematic variation of the applicant's sex and the omission or inclusion of a photo depicting the applicant as physically attractive or unattractive. As predicted, personnel decisions strongly reflected the operation of sex-role stereotypes. These factors similarly affected consultants' recommendations of alternatives to employment and consultants' causal attributions of applicants' projected occupational successes and failures. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Applied the system developed by R. Flesch to judge the reading ease and human interest of 34 books considered appropriate for beginning courses in psychology. Reading ease scores varied from 29.87 to 53.30, with 1 text classified as very difficult, 29 as difficult, and 4 as fairly difficult. Human interest scores ranged from 3.39 to 32.24; 10 books were rated dull, 19 mildly interesting, and 5 interesting. Although many factors are involved when choosing a text for a particular course, and the most readable and interesting book is not necessarily the best book, human interest and readability are criteria to be considered. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
TE Weaver NB Kribbs AI Pack LR Kline DK Chugh G Maislin PL Smith AR Schwartz NM Schubert KA Gillen DF Dinges 《Canadian Metallurgical Quarterly》1997,20(4):278-283
Caries of the pits and fissures of permanent teeth continues to be a problem for children, newly erupted permanent molars being particularly at risk. Oral hygiene measures have been shown to be able to reduce the incidence of caries. The aim of this study was to compare the caries-preventive effects on newly erupted first permanent molars of a professional tooth cleaning and oral health education program (test) with a standard preventive program (control), comprising selective fissure sealing and application of topical fluorides. School Dental Service clinics of the Health Department of Western Australia, in Perth, were assigned to four test or four control clinics. Schoolchildren, mean age 6.3 +/- 0.3 (s) years with sound, newly erupted first permanent molars were included in the study (207 test, 197 control). After 12 months, 186 test and 163 control children were examined by an examiner who was 'blind' to the test or control status of the children. Caries of the first permanent molars developed in 34 test and 35 control children; the estimated risk ratio was 0.86 (95% CI 0.56, 1.30). Children in the test group had an average DFT score of 0.26 +/- 0.62 compared with 0.29 +/- 0.64 DFT in the control group (t-test, P = 0.67). The 12-month results suggest that there was no statistically significant difference between the caries-preventive effects of a professional tooth cleaning and oral health education program and a program based on selective fissure sealing and application of topical fluorides. 相似文献
36.
Janowitz IL Gillen M Ryan G Rempel D Trupin L Swig L Mullen K Rugulies R Blanc PD 《Applied ergonomics》2006,37(5):641-658
BACKGROUND: Assessing the physical demands of the heterogeneous jobs in hospitals requires appropriate and validated assessment methodologies. METHODS: As part of an integrated assessment, we adapted Rapid Entire Body Assessment (REBA), using it in a work sampling mode facilitated by a hand-held personal digital assistant, expanding it with selected items from the UC Computer Use Checklist, and developed a scoring algorithm for ergonomics risk factors for the upper (UB) and lower body (LB). RESULTS: The inter-rater reliability kappa was 0.54 for UB and 0.66 for LB. The scoring algorithm demonstrated significant variation (ANOVA p<0.05) by occupation in anticipated directions (administrators ranked lowest; support staff ranked highest on both scores). A supplemental self-assessment measure of spinal loading correlated with high strain LB scores (r=0.30; p<0.001). CONCLUSION: We developed and validated a scoring algorithm incorporating a revised REBA schema adding computer use items, appropriate for ergonomics assessment across a range of hospital jobs. 相似文献
37.
We present a method to independently measure the refractive index and the thickness of materials having flat and parallel sides by using a combination of Michelson and Fabry-Perot interferometry techniques. The method has been used to determine refractive-index values in the infrared with uncertainties in the third decimal place and thicknesses accurate to within +/- 5 microm for materials at room and cryogenic temperatures. 相似文献
38.
A recently developed analytical technique, modulus profiling, conveniently allows the mechanical properties of elastomers to be mapped with spatial resclutions approaching 0.05 mm. Thus, spatial heterogeneities in modulus caused by processing and aging phenomena can be easily monitored. This paper describes some typical results from polymer aging studies, which Indicate the insights available from this technique. These include application of modulus profiling to understanding (1) mechanical property deterioration of Viton in an elevated temperature, gamma-radiation environment, (2) recent continuous stress-relaxation results, and (3) the role of ozone for non mechanically-stressed materials in high energy radiation environments. 相似文献
39.
J. Gillen K. Littleton † A. Twiner † J.K. Staarman‡ & N. Mercer‡ 《Journal of Computer Assisted Learning》2008,24(4):348-358
Abstract All communication is inherently multimodal, and understandings of science need to be multidimensional. The interactive whiteboard offers a range of potential benefits to the primary science classroom in terms of relative ease of integration of a number of presentational and ICT functions, which, taken together, offers new opportunities for fostering multifaceted pedagogic strategies. In this case study, we examine in detail how a teacher pursues two themes across four science lessons. We examine how the teacher creates continuity in her students' learning experiences through taking up some of the affordances of the IWB in order to represent scientific phenomena and engage children in activities to consolidate their understandings. Support is offered for the notion that while pedagogic goals and strategies must determine the selection of tools, rather than the 'tail wagging the dog' as in technology-focussed hyperbole, planned use of the interactive whiteboard, conceptualized as a 'heterogeneous mediational tool kit' ( Wertsch 1991 ), can be effectively integrated into teaching practice. 相似文献
40.
The Interaction of the Soybean Seed High Oleic Acid Oil Trait With Other Fatty Acid Modifications
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Kristin Bilyeu Mária Škrabišová Doug Allen Istvan Rajcan Debra E. Palmquist Anne Gillen Rouf Mian Hyun Jo 《Journal of the American Oil Chemists' Society》2018,95(1):39-49
Oil value is determined by the functional qualities imparted from the fatty acid profile. Soybean oil historically had excellent use in foods and industry; the need to increase the stability of the oil without negative health consequences has led to a decline in soybean oil use. One solution to make the oil stable is to have high oleic acid (>70%) and lower linolenic acid content in the oil. Other fatty acid profile changes are intended to target market needs: low‐saturated fatty acid and high stearic acid content in the oil. The objective of this study is to determine the interaction of the high oleic acid oil trait with other alleles controlling fatty acid profiles. Soybean lines containing high oleic acid allele combinations plus other fatty acid modifying alleles were produced, and the seed was produced in multiple field environments over 2 years. Stable high oleic acid with low linolenic acid (<3.0%) was achieved with a 4‐allele combination. The target of >20% stearic acid in the seed oil was not achieved. Reducing total saturated fatty acids below 7% in a high oleic acid background was possible with mutant alleles of both an acyl‐ACP thioesterase B and a β‐ketoacyl‐[acyl‐carrier‐protein] synthase III gene. The results identified allele combinations that met the target fatty acid profile thresholds and were most stable across environments. 相似文献