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1.
Margeaux A. Miller Prof. Dr. Ellen M. Sletten 《Chembiochem : a European journal of chemical biology》2020,21(24):3451-3462
Perfluorocarbons, saturated carbon chains in which all the hydrogen atoms are replaced with fluorine, form a separate phase from both organic and aqueous solutions. Though perfluorinated compounds are not found in living systems, they can be used to modify biomolecules to confer orthogonal behavior within natural systems, such as improved stability, engineered assembly, and cell-permeability. Perfluorinated groups also provide handles for purification, mass spectrometry, and 19F NMR studies in complex environments. Herein, we describe how the unique properties of perfluorocarbons have been employed to understand and manipulate biological systems. 相似文献
2.
The cyclooxygenase-2 (COX-2) is a potent enzyme that converts arachidonic acid to prostaglandins (PG), including PGE2, a key mediator of inflammation and angiogenesis. Importantly, COX-2 is activated in response to inflammatory stimuli, where it is also believed to promote the development and progression of head and neck cancers (HNC). COX-2 can mediate its protumorigenic effect through various mechanisms, such as inducing cell proliferation, inhibition of apoptosis, and suppressing the host’s immune response. Furthermore, COX-2 can induce the production of vascular endothelial growth factors, hence, promoting angiogenesis. Indeed, the ability of COX-2 inhibitors to selectively restrict the proliferation of tumor cells and mediating apoptosis provides promising therapeutic targets for cancer patients. Thus, in this comprehensive review, we summarized the reported differential expression patterns of COX-2 in different stages of head and neck carcinogenesis—from potentially premalignant lesions to invasive carcinomas. Furthermore, we examined the available meta-analysis evidence for COX-2 role in the carcinogenesis of HNC. Finally, further understanding of the biological processes of COX-2 and its role in orchestrating cell proliferation, apoptosis, and angiogenesis may give therapeutically beneficial insight to develop the management plan of HNC patients and improve their clinical outcomes. 相似文献
3.
Based on a contemporary cognitive-psychoanalytic theory (control-mastery theory; J. Weiss, H. Sampson, & Mount Zion Psychotherapy Research Group, 1986), this study proposed that college students have plans for college that consist of conscious and unconscious goals and obstructions to be overcome in meeting those goals. The construct of unconscious guilt was used to mediate the dual goals of autonomy and attachment. The idiographic plan-formulation method was adapted to derive plans for 12 sophomore women. Acceptable interjudge reliabilities and criterion validity were demonstrated, and several themes in the goals and obstructions were illustrated. Students worried more about mothers than about fathers, particularly when they perceived the mother as weak or needy. The potential of the method for generating inferences about unconscious process for normative development is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Ellen Y. Sun Kathleen B. Alexander Paul F. Becher Shyh-Lung Hwang 《Journal of the American Ceramic Society》1996,79(10):2626-2632
Interfacial microstructures in βP-Si3 N4 ( w )-Si-Al-Y-O-N-glass systems were investigated by systematically varying the nitrogen content and the Al:Y ratio of the glass matrix. High-resolution and analytical transmission electron microscopy (HREM and AEM) studies revealed that the interfacial microstructure is a function of the glass composition. No interfacial phases were formed in glasses with low Al:Y ratios and in glasses with high Al:Y ratios and low nitrogen content, whereas epitaxial growth of an interfacial layer (100–200 μm thick) on the βP-Si3 N4 ( w ) occurred in a glass matrix with high Al:Y ratio and high nitrogen content. The interfacial layer was identified to be a β'-SiAION phase. Interfaces containing the SiAION layer exhibited high debonding energy compared to Si3 N4 ( w )–glass interfaces. HREM studies indicated that the lattice-mismatch strain in the SiAION layer was relieved by dislocation formation at the SiAION–Si3 N4 ( w ) interface. The difference in interfacial debonding energy was, hence, attributed to the local atomic structure and bonding between the glass-β-Si3 N4 and the glass–β'-SiAION phases. This observation was clear evidence of the strong influence of glass chemistry on the interfacial debonding behavior by altering the interfacial microstructure. 相似文献
5.
Ellen Spolsky 《Computers and the Humanities》1993,27(5-6):323-329
Olsen is right to note what can be done with a good theory and the right machine. His particular theory, however, is not transferable to literary studies. If we need a new model, I would suggest that cognitive science can provide a few interesting ones. I have begun to do some work based on David Marr's VISION, in which he hypothesizes two levels of processing within the visual module. My speculation has been on the parallel existence of distinguishable levels of conceptual or language organization which would correspond to the viewer and object centered perspectives Marr describes for vision. I propose to explore the possibility that we may find here the model for the existence of stylistic individualism within overarching historical stylistic generalizations, and even more, that this may be what feminists are searching for when they try to resist being coopted by the masculine language of objectivity.
Ellen Spolsky teaches English literature and literary theory and is the Director of the Lechter Institute for Literary Research at Bar-Ilan University, Israel. Her latest book is Gaps in Nature: Literary Interpretation and the Modular Mind(SUNY Press, 1993). 相似文献
6.
Soft sediments from the Detroit River were analyzed for the USEPA priority pollutants to generally characterize contaminant distribution. Forty-three were detected. Highest heavy metal concentrations were found in the Trenton Channel and immediately downstream of Grosse Ile. They ranged from an area mean (N = 2) of 0.19 mg/kg mercury to 338.7 mg/kg zinc (dry weight). Polynuclear aromatic hydrocarbons ranged from 0.1 mg/kg to 38.8 mg/kg (mean, N = 2) with the highest levels near Grosse Ile. PCBs ranged from 0.015 mg/kg to 1.7 mg/kg (mean, N = 2). Organochlorine pesticides were not detected except for a trace of heptachlor in one sample. Sediment contamination in the Detroit River is widespread with higher concentrations on the U.S. side downstream of the Rouge River and in the Trenton Channel. The significance of these in-place pollutants to biota and as a source to Lake Erie is still unknown. 相似文献
7.
A total of 188 employed mothers and fathers and their 5–7 yr-old child participated in a study of the relations between the nature of adults' work and their parenting attitudes and behaviors (a line of research influenced by both socialization and stress perspectives). In general, positive features of work (i.e., complexity of work with people, challenge, and stimulation) tended to be associated with both self-report and observational measures of developmentally sound parenting (e.g., less harsh discipline, more warmth and responsiveness). Interaction effects indicated that gender of parent and child further condition these relations. Analyses partially support the interpretation that conditions of work influence parenting through their effect on mood but also suggest that certain conditions of work may directly socialize behavior in the parental role (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Aging free from negative stereotypes: Successful memory in China among the American deaf. 总被引:1,自引:0,他引:1
This study explores whether negative stereotypes about aging contribute to memory loss in old age. The research participants consisted of old and young Chinese hearing, American Deaf, and American hearing individuals. Members of the mainland Chinese and the American Deaf cultures were recruited on the basis of the belief that they would be less likely than hearing Americans to be exposed to and accept negative stereotypes about aging. The expected results were (1) an interaction in which the 3 groups of younger Ss would perform similarly on the memory tasks, whereas the older Deaf and older Chinese participants would outperform the older American hearing group and (2) a positive correlation between view toward aging and memory performance among the old Ss. The data supported both hypotheses. The results suggest that cultural beliefs about aging play a role in determining the degree of memory loss people experience in old age. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Interest has increased during recent years in using microcomputers for implementation of network reliability algorithms. There are indications that some implementations suffer severe restrictions imposed by such a computing environment, whereas some other results indicate otherwise. This brief note attempts to clarify the apparently contradictory conclusions that would be naturally drawn from recent papers that treat this subject. 相似文献
10.
Rattok Jack; Ross Barbara; Ben-Yishay Yehuda; Ezrachi Ora; Silver Saralyn; Lakin Phyllis; Vakil Eli; Piasetsky Eugene; Zide Ellen; Diller Leonard 《Canadian Metallurgical Quarterly》1992,6(4):395
Within a clinical demonstration program, 59 traumatically brain-injured patients were treated with 1 of 3 mixes of treatment. Mix 1 included cognitive remediation (CGR), small-group interpersonal (SGI) communication training, therapeutic community activities, and personal counseling. Mix 2 was similar to Mix 1 but stressed SGI exercises and eliminated CGR. Mix 3 emphasized CGR and eliminated SGI exercises. The efficacy of the treatment mixes was evaluated with performance on neuropsychological tests, improved independence in functional activities, measures of intra- and interpersonal functioning, and vocational outcome. Ss' participation in the program, irrespective of treatment mix, yielded improvements in (1) self-image, (2) quality of interpersonal relatedness and interaction, (3) involvement with others in naturalistic settings, and (4) vocational outcome. Overall, data point to the superiority of the balanced mix (Mix 1) over Mixes 2 and 3. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献