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排序方式: 共有255条查询结果,搜索用时 31 毫秒
1.
WENXI GAO QIANQIAN MA CHENYU TANG YUELI ZHAN YINONG DUAN HUIHUA NI YUNZHAO XU 《Biocell》2020,44(4):597-605
Cervical cancer (CESC) is one of the most common cancers and affects the female genital tract. Consistent HPV
infection status has been determined to be a vital cause of tumorigenesis. HPV infection may induce changes to the
immune system and limit the host’s immune response. Immunotherapy is therefore essential to improving the overall
survival of both locally advanced and recurrent CESC patients. Using 304 relevant samples from TCGA, we assessed
immune cell function in CESC patients to better understand the status of both tumor micro-environment cells and
immune cells in CESC. Functional enrichment analysis, pathway enrichment analysis, and PPI network construction
were performed to explore the differentially expressed genes (DEGs). The analysis identified 425 DEGs, which
included 295 up-regulated genes and 130 down-regulated genes. We established that upregulation of CCL5 was
correlated with significantly better survival, meaning that CCL5 expression could serve as a novel prognostic
biomarker for CESC patients. We further focused on CCL5 as a hub gene in CESC, as it had significant correlations
with increased numbers of several types of immune cells. Cell-type fractions of M1 macrophages were significantly
higher in the high-immune-scores group, which was associated with better overall survival. Finally, we concluded that
CCL5 is a promising prognostic biomarker for CESC, as well as a novel chemotherapeutic target. 相似文献
2.
Preacher Kristopher J.; Rucker Derek D.; MacCallum Robert C.; Nicewander W. Alan 《Canadian Metallurgical Quarterly》2005,10(2):178
Analysis of continuous variables sometimes proceeds by selecting individuals on the basis of extreme scores of a sample distribution and submitting only those extreme scores to further analysis. This sampling method is known as the extreme groups approach (EGA). EGA is often used to achieve greater statistical power in subsequent hypothesis tests. However, there are several largely unrecognized costs associated with EGA that must be considered. The authors illustrate the effects EGA can have on power, standardized effect size, reliability, model specification, and the interpretability of results. Finally, the authors discuss alternative procedures, as well as possible legitimate uses of EGA. The authors urge researchers, editors, reviewers, and consumers to carefully assess the extent to which EGA is an appropriate tool in their own research and in that of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Bayazit Mahmut; Hammer Tove Helland; Wazeter David L. 《Canadian Metallurgical Quarterly》2004,89(4):738
Methodological problems in studies of union commitment were identified and illustrated with data from 4,641 members and 479 stewards in 297 local teachers' unions. Using a 20-item union commitment scale, results confirmed the existence of 3 substantive factors and 1 method factor at the individual level of analysis: loyalty to the union, responsibility to the union, willingness to work for the union, and a factor of negatively worded items. Tests of measurement invariance showed that the scale captured commitment for rank-and-file members but not for union stewards. The authors also found partial measurement invariance between long-time and newer members and full measurement invariance between men and women. Finally, the authors found that violation of the statistical assumption of independence reduced model fit when individual commitment scores were analyzed without attention to the hierarchical nature of the data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
绩优问题生,指学业成绩优异、但心理有疾患的大学生。为增强教育的针对性,促进绩优问题生的健康成长和全面发展,本文从家庭、学校、个人三个方面对其进行成因分析,并提出相应教育对策。 相似文献
5.
Mosaicing is connecting two or more images and making a new wide area image with no visible seam-lines. Several algorithms
have been proposed to construct mosaics from image sequence where the camera motion is more or less complex. Most of these
methods are based either on the interest points matching or on theoretical corner models. This paper describes a fully automated
image-mosaicing method based on the regions and the Harris points primitives. Indeed, in order to limit the search window
of potential homologous points, for each point of interest, regions segmentation and matching steps are being performed. This
enables us to improve the reliability and the robustness of the Harris points matching process by estimating the camera motion.
The main originality of the proposed system resides in the preliminary manipulation of regions matching, thus making it possible
to estimate the rotation, the translation and the scale factor between two successive images of the input sequence. This estimation
allows an initial alignment of the images along with the framing of the interest points search window, and therefore reducing
considerably the complexity of the interest points matching algorithm. Then, the resolution of a minimization problem, altogether
considering the couples of matched-points, permits us to perform the homography. In order to improve the mosaic continuity
around junctions, radiometric corrections are applied. The validity of the herewith described method is illustrated by being
tested on several sequences of complex and challenging images captured from real-world indoor and outdoor scenes. These simulations
proved the validity of the proposed method against camera motions, illumination variations, acquirement conditions, moving
objects and image noise. To determine the importance of the regions matching stage in motion estimation, as well as for the
framing of the search window associated to a point of interest, we compared the matching points results of this described
method with those produced using the zero-mean normalized cross correlation score (without regions matching). We made this
comparison in the case of a simple motion (without the presence of a rotation around optical axis and/or a scale factor),
in the case of a rotation and in the general case of an homothety. For justifying the effectiveness of this method, we proposed
an objective assessment by defining a reconstruction error.
相似文献
Slim AmriEmail: |
6.
从天然氨基酸的50个性质参数中经主成分分析得出1种新的氨基酸描述子:氨基酸特征性质得分.并在此基础上通过定义基于向量形式的自相关函数以及引入Mercer核技术将该函数运算空间进行非线性变换,最终提出了1种新的蛋白质序列表征方法:核序列自相关函数.采用该函数对632个已知晶体结构的非同源蛋白分类研究结果表明:KSACF能... 相似文献
7.
ADIL Gulam 《数字社区&智能家居》2008,(35)
该文以和田师专学生档案管理为研究背景,结合学生档案管理系统的设计与实现,研究了基于分布式应用系统原理、设计和实现的问题。全国各大专院校及一些中专和中学的校园网建设已进入蓬勃发展的阶段。校园网建成以后,需要在校园网上建设一个全校范围的、开放的、分布的学生档案管理系统。文中论述了符合新疆特色的大专学校学生档案管理系统的一般构成,论述了校园网络与学生档案管理系统的关系。 相似文献
8.
Comments on an article by C. M. Stoup and L. T. Benjamin, Jr. (see record 1983-24200-001), in which they used various editions of Graduate Study in Psychology, published by the American Psychological Association (APA), to report the GPAs and Graduate Record Examination scores of master's and doctoral students across various areas of psychology. It is cautioned that the use of Graduate Study in Psychology as a data source calls for skepticism, as there is sufficient reason to question some of the data that are submitted to the APA by psychology departments. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
The Wechsler Adult Intelligence Scale--Third Edition (WAIS-III; D. Wechsler, 1997a) and the Wechsler Memory Scale--Third Edition (WMS-III; D. Wechsler, 1997b) are 2 of the most frequently used measures in psychology and neuropsychology. To facilitate the diagnostic use of these measures in the clinical decision-making process, this article provides information on education-stratified, directional prevalence rates (i.e., base rates) of discrepancy scores between the major index scores for the WAIS-III, the WMS-III, and between the WAIS-III and WMS-III. To illustrate how such base-rate data can be clinically used, this article reviews the relative risk (i.e., odds ratio) of empirically defined "rare" cognitive deficits in 2 of the clinical samples presented in the WAIS-III--WMS-III Technical Manual (The Psychological Corporation, 1997). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
This investigation examined whether cognition serves as a direct factor, mediates, or moderates the relationship between stressful life events and Children's Depression Inventory (CDI; Kovacs, 1992) factor scores in urban, ethnic minority youth. Ninety-eight middle school students completed measures of stressful life events, cognition (cognitive triad and locus of control), and depressive symptoms. Results provided support for both mediating and moderating models of depression. Specifically, the cognitive triad mediated the relationship between stressful life events and depressive symptom categories of negative mood, ineffectiveness, and anhedonia, while it interacted with stressful life events to predict negative self-esteem. In addition, locus of control was found to interact with stressful life events to predict anhedonia. Finally, the diathesis-stress model was not supported when predicting the CDI Interpersonal Problems factor score, which taps externalizing behaviors. Implications for school psychology research and practice include the importance of including measures of stressful life events and cognitive styles in assessment of children's social-emotional functioning. In addition, results highlight the need to target children's perceptions for intervention since they appear to play a significant role in psychological reactions to stressors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献