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排序方式: 共有822条查询结果,搜索用时 15 毫秒
31.
32.
Musculoskeletal disorder risk was assessed during automotive assembly processes. The risk associated with current assembly processes was compared to using a cantilever chair intervention. Spine loads and normalized shoulder muscle activity were evaluated during assembly in eight regions of the vehicle. Eight interior cabin regions of the vehicle were classified by reach distance, height from vehicle floor and front to back. The cantilever chair intervention tool was most effective in the far reach regions regardless of the height. In the front far reach regions both spine loads and normalized shoulder muscle activity levels were reduced. In the middle and close reach regions spine loads were reduced, however, shoulder muscle activity was not, thus an additional intervention would be necessary to reduce shoulder risk. In the back far reach region, spine loads were not significantly different between the current and cantilever chair conditions. Thus, the effectiveness of the cantilever chair was dependent on the region of the vehicle. 相似文献
33.
Approximately 75% of the PAF present in saliva is recovered on extraction of whole saliva (0.8 vol) with chloroform/methanol/water
(2∶2∶1 v/v/v). PAF levels, determined by our recently developed radioimmunoassay, in saliva extracts ranged from 0.5–21 ng/mL
with 59% between 2–6 ng/mL. These figures, for apparently healthy subjects, are higher than previously reported levels obtained
by platelet assays. The validity of our radioimmunoassay results was checked by isolating and quantitating the PAF fraction
from whole saliva. In addition, when we examined our saliva samples by platelet aggregation, low levels of PAF, comparable
with the values found in the literature, were detected. Investigations revealed the presence of a substance(s) which inhibited
PAF-induced platelet aggregation but which did not affect the radioimmunoassay. 相似文献
34.
Phillips Tamara J.; Broadbent Julie; Burkhart-Kasch Sue; Henderson Carly; Wenger Charlotte D.; McMullin Carrie; McKinnon Carrie S.; Cunningham Christopher L. 《Canadian Metallurgical Quarterly》2005,119(4):892
Short-term selective breeding created mouse lines divergent for ethanol drinking (high drinking short-term selected line [STDRHI], low drinking [STDRLO]) or ethanol-induced conditioned taste aversion (CTA; high [HTA], low [LTA]). Compared with STDRLO, STDRHI mice consumed more saccharin and less quinine, exhibited greater ethanol-induced conditioned place preference (CPP), and showed reduced ethanol stimulation and sensitization under some conditions; a line difference in ethanol-induced CTA was not consistently found. Compared with LTA, HTA mice consumed less ethanol but were similar in saccharin consumption, sensitivity to ethanol-induced CPP, and ethanol-induced locomotor stimulation and sensitization. These data suggest that ethanol drinking is genetically associated with several reward-and aversion-related traits. The interpretation of ethanol-induced CTA as more genetically distinct must be tempered by the inability to test the CTA lines beyond Selection Generation 2. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Hall Gordon C. Nagayama; Teten Andra L.; DeGarmo David S.; Sue Stanley; Stephens Kari A. 《Canadian Metallurgical Quarterly》2005,73(5):830
Explanatory models of sexual aggression were examined among mainland Asian American (n = 222), Hawaiian Asian American (n = 127), and European American men (n = 399). The Malamuth et al. (N. M. Malamuth, D. Linz, C. L. Heavey, G. Barnes, & M. Acker, 1995; N. M. Malamuth, R. J. Sockloskie, M. P. Koss, & J. S. Tanaka, 1991) confluence model of sexual aggression, which posits impersonal sex and hostile masculinity as paths to sexual aggression, was consistently supported. Culture-specific moderators of sexual aggression were also identified. Whereas loss of face was a protective factor against sexual aggression in the Asian American samples, it generally was not a protective factor among European Americans. These findings are not a function of actual or perceived minority status. An implication is that theoretical models may need to be augmented with cultural constructs for optimal application in certain ethnic group contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Evans Theodore Avery; Howell Sue; Westergaard Gregory Charles 《Canadian Metallurgical Quarterly》2005,31(4):399
Research on cross-modal performance in nonhuman primates is limited to a small number of sensory modalities and testing methods. To broaden the scope of this research, the authors tested capuchin monkeys (Cebus apella) for a seldom-studied cross-modal capacity in nonhuman primates, auditory-visual recognition. Monkeys were simultaneously played 2 video recordings of a face producing different vocalizations and a sound recording of 1 of the vocalizations. Stimulus sets varied from naturally occurring conspecific vocalizations to experimentally controlled human speech stimuli. The authors found that monkeys preferred to view face recordings that matched presented vocal stimuli. Their preference did not differ significantly across stimulus species or other stimulus features. However, the reliability of the latter set of results may have been limited by sample size. From these results, the authors concluded that capuchin monkeys exhibit auditory-visual cross-modal perception of conspecific vocalizations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
38.
John E. Rash Timothy J. A. Johnson C. Sue Hudson F. Dennis Giddings William F. Graham Mohyee E. Eldefrawi 《Journal of microscopy》1982,128(2):121-138
Three methods are described for direct post-fracture, post-shadow labelling of individual classes of intramembrane particles (IMPs) in freeze-fracture replicas of biological membranes. The P-face IMPs corresponding to the acetylcholine receptor complexes (AChRs) of vertebrate neuroeffector junctions are identified by post-replication labelling with ferritin-antibody complexes and with neurotoxin-biotin-avidin-colloidal gold affinity ligands. (The freeze-etch nomenclature of Branton et al., 1975, is used in this report.) These post-shadow labelling techniques resemble conventional en bloc labelling techniques except that the labelling reagents must penetrate a thin but discontinuous layer of platinum superimposed on the molecules of interest. In the ‘sectioned labelled-replica technique’, the replicated and labelled tissues are stained, embedded in plastic and sectioned parallel to the replica-tissue interfaces. In the direct ‘labelled-replica techniques’, the replicated and labelled samples are freeze-dried or critical point dried, the labelled surfaces are stabilized by carbon coating, and the underlying tissues are dissolved, allowing the labelled-replicas to be examined as conventional freeze-fracture replicas. The unshadowed side of each AChR IMP is shown to retain sufficient biochemical information to permit both immunospecific and neurotoxin specific labelling despite formaldehyde fixation, freezing, fracturing, platinum shadowing, and thawing in aqueous media. A new mixed ferricyanide-osmium staining method reveals electron opaque structures spanning the membrane bilayer in the same size, number and distribution as the labelled IMPs. These experiments demonstrate the feasibility of identifying individual IMPs in freeze-fracture replicas and may allow the identification of specific membrane lesions in human disease. 相似文献
39.
分析仪器和其他传统工业一样,正在信息技术的改造下,向微型化、智能化、自动化和网络化方向发展。分析仪器作为数据获得的源头技术,必将在信息技术发展中起到重要作用,将从被动转向主动,并促进信息技术的发展。分析工作者也将是未来物联网不可或缺的生力军。 相似文献
40.
Y Lee SA Lee JY Choi M Song H Sung S Joen SK Park KY Yoo DY Noh SH Ahn D Kang 《Nutrition journal》2012,11(1):59
ABSTRACT: BACKGROUND: The 5-year survival rate for breast cancer among Korean women has increased steadily; however, breast cancer remains the leading cause of cancer mortality among women. One-carbon metabolism, which requires an adequate supply of methyl group donors and B vitamins, may affect the prognosis of breast cancer. This aim of this study was to investigate the associations of dietary intake of vitamin B2, vitamin B6 and folate before diagnosis on the prognosis of breast cancer. METHODS: We assessed the dietary intake using a food frequency questionnaire with 980 women who were newly diagnosed and histopathologically confirmed to have primary breast cancer from hospitals in Korea, and 141 disease progression events occurred. Cox's proportional hazard regression models were used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) adjusting for age, education, recruitment sites, TNM stage, hormone status, nuclear grade and total calorie. RESULTS: There was no significant association between any one-carbon metabolism related nutrients (vitamin B2, B6 and folate) and the progression of breast cancer overall. However, one-carbon metabolism related nutrients were associated with disease progression in breast cancer patients stratified by subtypes. In ER + and/or PR + breast cancers, no association was observed; however, in ER--/PR-- breast cancers, a high intake of vitamin B2 and folate statistically elevated the HR of breast cancer progression (HR = 2.28; 95% CI, 1.20-4.35, HR = 1.84; 95% CI, 1.02-3.32, respectively) compared to a low intake. This positive association between the ER/PR status and progression of the disease was profound when the nutrient intakes were categorized in a combined score (Pinteraction = 0.018). In ER--/PR-- breast cancers, high combined scores were associated with a significantly poor DFS compared to those belonging to the low score group (HR = 3.84; 95% CI, 1.70-8.71). CONCLUSIONS: In conclusion, our results suggest that one-carbon related nutrients have a role in the prognosis of breast cancer depending on the ER/PR status. 相似文献