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101.
Cell migration is a finely tuned biological process that often involves epithelial-mesenchymal transition (EMT).
EMT is typically characterized by the upregulation of mesenchymal markers such as Snail1. This process has been shown
to be of critical importance to normal developmental processes, including neural crest migration and invasion.
Interestingly, similar mechanisms are utilized in disease processes, such as tumor metastasis and migration. Notably,
EMT and EMT-like processes confer tumor cells with the ability to migrate, invade, and adopt stem cell-like
properties that largely account for immunosuppression and tumor recurrence. Therefore, identifying sensitive EMT
markers may contribute to cancer prognosis and diagnosis in many facets. Previously, we showed that Elp3 plays an
essential role during neural crest migration by stabilizing Snail1. In the current study, we further elucidate the
molecular mechanism underlying colorectal cancer migration. We found that mElp3 exerted an identical function to
xElp3 in modulating neural crest migration, and both HAT and SAM domains are imperative during this migratory
process. Interestingly, overexpression of mElp3 in SW480 cells promoted cell migration and invasion, and we further
showed that Elp3 stabilized Snail1 requiring integrity of both SAM and HAT domains. Our findings warrant further
exploration of the specific target of Elp3 in cancer cells. 相似文献
102.
MV Panchyshyna YA al-Qdemat JM Panchyshyn LI Petruh TG Kazmirchuk 《Canadian Metallurgical Quarterly》1997,17(1):47-52
Studies on the wake-sleep cycle with participation of eight female volunteers were performed before, during, and after a 120-day bed rest with the head-end of bed tilted down at 6 degrees (HDT). Methods of polysomnography and actography were applied. The test-subjects were assigned into 2 groups. Group A was prescribed to use countermeasures throughout the experiment; no countermeasures was administered by group B. Evidence of significant alteration in sleep structure at different time points in HDT is given in comparison with data about females of the control group under the conditions of everyday activity. Sleep deviations in the subjects were reordered at each of the three points of investigation and differed from those in control. HDT was shown to modify the sleep structure in experimental groups A and B. A supposition is made that under these conditions the dynamics of physical activity during night sleep had an adaptive character. 相似文献
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105.
地坪涂装材料已经成为建筑地面的主要装饰材料之一.随着地坪材料的多品种、多元化发展,其质量问题越来越受人们关注.为了控制其有害物质限量,减少溶剂使用,降低溶剂型地坪材料对环境及人身的危害,国家标准化管理委员会下达了<环保型地坪涂装材料>国家标准的制订任务,由上海市建筑科学研究院作为标准第一起草单位负责制订.主要探讨标准编制过程中对于有害物质限量和防滑性技术要求的制订方法. 相似文献
106.
基于对中国工程建设实际情况的分析,从建设市场、国家法律和研究成果等几个大的方面论述了中国工程项目管理的国内环境,从而分析了我国建设市场对工程项目管理的需求。 相似文献
107.
以肉制品中常见的蜡状芽孢杆菌为研究对象,采用中心组合设计方法考察温度(88~96℃)、pH(5.1~6.3)、氯化钠浓度(1.5%~3.5%,w/v)和初始菌数(4~7log10 CFU/mL)的交互作用对蜡状芽孢杆菌消长规律的影响。不同环境因子作用下菌株D值的响应面分析结果显示,响应面回归方程中无失拟因素存在,预测值与实测值达到较好的拟合(R^2=0.9644)。不同环境因子作用下蜡状芽孢杆菌消长规律的方差分析显示,环境因子的交互作用有极显著影响(P〈0.01),其中温度和pH的影响达到极显著水平(P〈0.01),初始菌数的影响达到显著水平(P〈0.05),氯化钠浓度的影响不显著(P〉0.05)。 相似文献
108.
109.
The role of nerve growth factor (NGF) and of the neurotrophin receptor p75 (p75(NTR)) in programmed cell death was investigated in the retina and the spinal cord of mouse embryos. Large numbers of cells express p75(NTR) in and along the developing optic nerve and in the mantle zone of the spinal cord. In embryos carrying deletions in the ngf or the p75(NTR) gene, cell death was reduced in the retina and in the spinal cord. Increased numbers of Islet-1-immunoreactive cells were detected in the dorsal spinal cord, and the mantle zone was enlarged in both mutants. These results indicate that NGF/p75(NTR)-dependent mechanisms are used to remove cells when axonal tracts elongate in developing neuroepithelia. 相似文献
110.
AK Metzger G Mohapatra YA Minn AW Bollen K Lamborn FM Waldman CB Wilson BG Feuerstein 《Canadian Metallurgical Quarterly》1999,90(2):306-314
OBJECT: This study was conducted to determine whether comparative genomic hybridization (CGH) is a more sensitive method for detecting genetic aberrations than other tests currently in use. METHODS: The authors used CGH to examine 40 primary and 13 recurrent adenomas obtained from 52 patients for loss and gain of genetic material. Copy number aberrations (CNAs) were detected in 25 (48%) of the 52 patients studied. The chromosomes affected were, in order of decreasing frequency, 11, 7, X, 1, 8, 13, 5, 14, 2, 6, 9, 10, 12, 3, 18, 21, 4, 16, 15, 19, 22, and Y. Endocrinologically active adenomas were more likely to contain (p = 0.009) and had a greater number (p = 0.003) of CNAs. Of 26 adenomas with CNAs, 18 showed multiple aberrations involving entire chromosomes or chromosome arms. The most frequent CNA involving a chromosome subregion, which was present in four (8%) of 53 adenomas, was the loss of all chromosome 11 material except for a preserved common segment containing 11q13. Immunoperoxidase staining did not detect cyclin D1 expression in those four cases, making cyclin D1 an unlikely target of this rearrangement. CONCLUSIONS: These findings indicate that genetic abnormalities are present in pituitary adenomas at a higher rate than previously reported, are associated with endocrinological activity, and often involve several chromosomes. Rearrangement at 11q13 may inactivate a tumor suppressor gene or activate an oncogene that is important in the initiation or progression of sporadic pituitary adenomas. 相似文献