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991.
为了探讨脑胶质母细胞瘤术后放疗对肝细胞生长因子受体表达规律的影响,对25例胶质母细胞瘤患者进行研究。结果显示肝细胞生长因子受体在复发前接受放疗与未接受放疗的患者中,复发后肝细胞生长因子受体表达及复发时间差异明显(P〈0.05)。因此放疗能对肝细胞生长因子受体在胶质母细胞瘤的表达产生影响,进而影响到其复发时间。 相似文献
992.
中国人群脂肪肝主要影响因素的荟萃分析 总被引:1,自引:1,他引:0
为系统评价中国居民脂肪肝发病的主要危险因素,检索文献数据库,收集国内1997年~2008年有关脂肪肝发病危险因素的16篇文献,利用Meta分析方法,进行综合统计分析,累计病例7200例,对照11884例。结果超重(23≤BMI〈25)、肥胖(BMI≥25)、过量饮酒、吸烟、高脂饮食、食用蔬菜、饮绿茶、爱好运动、运动少、高脂血症、高HDL—Ch、低HDL-Ch、高血压、高血糖、高血总胆固醇(≥6.5mmol/L)及糖尿病合并0R值(95%CI)分别为1.68(0.68~3.90)、5.01(3.23~7.76)、3.52(1.52~8.15)、1.18(1.01~1.37)、2.82(1.50~5.31)、0.45(0.37~0.55)、0.52(0.43~0.64)、0.32(0.14~O.74)、3.49(1.26~9.65)、4.91(2.69~8.96)、0.31(0.17~0.57)、2.14(1.50~3.03)、2.19(1.43~3.35)、2.75(1.66~4.58)、2.96(0.26~32.98)、2.29(1.30~4.01)。结论为目前影响中国人群脂肪肝发生的危险因素依次为肥胖、高脂血症、饮酒、运动少、高脂饮食、高血糖、糖尿病、高血压、低HDL—Ch和吸烟;保护因素为饮用绿茶,食用蔬菜,以及高HDL—ch;尚不能确定与中国人脂肪肝发生的相关性因素为超重和高血胆固醇。 相似文献
993.
血管内皮生长因子(vascular endothelial growth factor,VEGF)是一高度特异作用于内皮细胞的糖蛋白,是目前发现的最重要的肿瘤血管生长因子之一。结直肠癌的生长、侵袭和转移与血管内皮生长因子有密切的关系,VEGF在结直肠癌治疗中的作用日益突出。本文就VEGF的功能、在结直肠癌中的表达和治疗的作用作一综述。 相似文献
994.
血管内皮生长因子(vascular endothelial growth factor,VEGF)是一高度特异作用于内皮细胞的糖蛋白,是目前发现的最重要的肿瘤血管生长因子之一.结直肠癌的生长、侵袭和转移与血管内皮生长因子有密切的关系,VEGF在结直肠癌治疗中的作用日益突出.本文就VEGF的功能、在结直肠癌中的表达和治疗的作用作一综述. 相似文献
995.
The Test of Self-Conscious Affect (TOSCA) is a well-established scenario-based questionnaire assessing self-conscious emotions, such as shame and guilt, which have been shown to be differentially associated with a variety of functional, motivational, behavioral and health outcomes. The aim of this study was to evaluate the psychometric properties and internal structure of a Swedish version of TOSCA in a sample of 361 healthy adults. The psychometric properties and internal consistency of the Swedish version were at level with the original US TOSCA version for shame, guilt and detachment. The internal structure of the Swedish version was acceptable for shame, guilt and detachment but contained shortcomings in assessment of externalization. 相似文献
996.
This paper reports the further testing of a research instrument to examine the expectations and self-perceptions of employability of business students at post-graduate level, building on previously reported research with undergraduates [Rothwell, A., Herbert, I., & Rothwell, F. (2008). Self perceived employability: Construction and initial validation of a scale for university students. Journal of Vocational Behavior, 73(1), 1-12]. On this occasion the scale was again found to have a good internal reliability coefficient (α = .84), and discriminant validity from university commitment. Forcing a four-factor solution found components relating to the university’s reputation, individual self-confidence and proactivity, external labor market factors, and finally the individuals’ engagement with study and academic performance. For this multi-cultural post-graduate sample, perceptions of employability were good, but within that they placed significant emphasis on the brand and reputation of the university. Results indicate the potential for further studies with refined scales, particularly the combined scale of employability and ambition. 相似文献
997.
Research examining links between personality and interest have typically focused on links between measures of the five factor model and Holland’s RIASEC types. However, the five factor model of personality can be divided in to a larger set of narrow domain personality scales measuring facets of the ‘big five’ traits. Research in a number of fields indicates that facet scales are effective for clarifying the relationship between personality and other broad constructs, including academic achievement, job performance, stress and coping, and achievement motivation. In the present study links between personality facets and the RIASEC model were examined using property vector fitting. Obtained results are consistent with previous research suggesting that the use of facet-level personality measures can clarify relations between personality and other constructs, and provides new information linking personality facets and interests. The use of facet-level measures of personality expands the range of personality concepts that can be presented to individuals who are exploring career options. 相似文献
998.
Michael E. Young M.H. Clark Andrea Goffus Michael R. Hoane 《Learning and motivation》2009,40(2):160-165
Morris water maze data are most commonly analyzed using repeated measures analysis of variance in which daily test sessions are analyzed as an unordered categorical variable. This approach, however, may lack power, relies heavily on post hoc tests of daily performance that can complicate interpretation, and does not target the nonlinear trends evidenced in learning data. The present project used Monte Carlo simulation to compare the relative strengths of the traditional approach with both linear and nonlinear mixed effects modeling that identifies the learning function for each animal and condition. Both trend-based mixed effects modeling approaches showed much greater sensitivity to identifying real effects, and the nonlinear approach provided uniformly better fits of learning trends. The common practice of removing a rat from the maze after 90 s, however, proved more problematic for the nonlinear approach and produced an underestimate of y-axis intercepts. 相似文献
999.
A method is presented for marginal maximum likelihood estimation of the nonlinear random coefficient model when the response
function has some linear parameters. This is done by writing the marginal distribution of the repeated measures as a conditional
distribution of the response given the nonlinear random effects. The resulting distribution then requires an integral equation
that is of dimension equal to the number of nonlinear terms. For nonlinear functions that have linear coefficients, the improvement
in computational speed and accuracy using the new algorithm can be dramatic. An illustration of the method with repeated measures
data from a learning experiment is presented. 相似文献
1000.
The epistemic implications of engineering rhetoric 总被引:1,自引:0,他引:1
Louis L. Bucciarelli 《Synthese》2009,168(3):333-356
The texts (and talk) of engineers take different forms. In this essay, I present and critique several texts written for different purposes and audiences but all intended to convey to the reader the technical details of whatever they are about—whether a textbook passage describing the fundamental behavior of an electrical component, a journal article about a mathematical technique intended for use in design optimization, a memo to co-workers within a firm about a heat transfer analysis of a remotely sited building, or a general introduction to the field of? ergonomics? My aim is to explore how the ways in which engineers describe and document their problems and projects frame what they accept, display and profess as useful knowledge. In this I am particularly interested in how engineers envision the ‘users’ of, or participants in, their productions. Like science, engineering texts are written as if they were timeless and untainted by socio-cultural features. However, a technical treatise is not devoid of metaphor or creative rendering of events; there is always a narrative within which worldly data and instrumental logic is embedded—but it is a story in which the passive voice prevails, history is irrelevant, and the human actor or agent is painted in quantitative parameters fitting the occasion. Whether this rhetoric can be sustained in the face of challenges to traditional ways of doing engineering is an open question. 相似文献