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排序方式: 共有924条查询结果,搜索用时 15 毫秒
81.
Yourong Feng Qi Chen Sien Yee Lau Bridget W. Tsai Katie Groom Carolyn J. Barrett Lawrence W. Chamley 《International journal of molecular sciences》2022,23(21)
Placental extracellular vesicles (EVs) have increasingly been recognized as a major mediator of feto-maternal communication. However, the cellular and molecular mechanisms of the uptake of placental EVs by recipient cells are still not well-understood. We previously reported that placental EVs target a limited number of organs in vivo. In the current study, we investigated the mechanisms underlying the uptake of placental EVs into target cells. Placental EVs were derived from explant cultures of normal or preeclamptic placentae. The mechanisms underlying the uptake of placental EVs were elucidated, using the phagocytosis or endocytosis inhibitor, trypsin-treatment or integrin-blocking peptides. The endothelial cell activation was studied using the monocyte adhesion assay after the preeclamptic EVs exposure, with and/or without treatment with the integrin blocking peptide, YIGSR. The cellular mechanism of the uptake of the placental EVs was time, concentration and energy-dependent and both the phagocytosis and endocytosis were involved in this process. Additionally, proteins on the surface of the placental EVs, including integrins, were involved in the EV uptake process. Furthermore, inhibiting the uptake of preeclamptic EVs with YIGSR, reduced the endothelial cell activation. The interaction between the placental EVs and the recipient cells is mediated by integrins, and the cellular uptake is mediated by a combination of both phagocytosis and endocytosis. 相似文献
82.
83.
Lesonsky Elaine M.; Kaplan Marvin L.; Kaplan Netta R. 《Canadian Metallurgical Quarterly》1986,23(1):41
Developed a coding system to operationalize the Gestalt therapy formulation of experiential organization and used the scale to test the assumption that each member of an interacting couple is influenced by concurrent organization of experience processes of the other. 20 couples (at least 1 member was an undergraduate student) who had lived together for at least 6 mo were rated. Findings support the reliability of the procedure, but data do not reflect adequate levels of usage along the full range of the scale. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Borman Walter C.; Hanson Mary Ann; Oppler Scott H.; Pulakos Elaine D.; White Leonard A. 《Canadian Metallurgical Quarterly》1993,78(3):443
Explores the role of early supervisory experience and cognitive ability in 1st-line supervisor performance. Similar to the F. L. Schmidt et al (see record 1986-31441-001) study of nonsupervisors, this research tested structural models hypothesizing relationships among supervisory experience, cognitive ability, supervisory knowledge and proficiency, and performance ratings, using a sample of 570 2nd-tour soldiers. The Schmidt et al model with an additional ability?→?experience path provided the best fit. The significant ability?→?experience path was interpreted as indicating that demonstrated ability contributes to soldiers being given the opportunity to obtain supervisory experience. Experience had a greater impact on supervisor proficiency than on supervisor knowledge. Ability had a greater impact on supervisor knowledge than on proficiency. Discussion focuses on the personal characteristics that might be involved in being assigned supervisory responsibilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Elaine M. Huang Elizabeth D. Mynatt Jay P. Trimble 《Personal and Ubiquitous Computing》2007,11(7):537-547
Large interactive displays for supporting workgroup collaboration comprise a growing area of ubiquitous computing research
and many such systems have been designed and deployed in laboratory studies and research settings. Such displays face difficulties
in real-world deployments, as they are often supplemental technologies as opposed to primary tools for work activities. In
this work, we investigate the integration and uptake of the NASA MERBoards, shared interactive displays that were deployed
to support science tasks in the Mars Exploration Rover (MER) missions. We examine the hurdles to adoption imposed specifically
by the real-world circumstances of the deployment that were external to the design of the system, and explain how these concerns
apply to the general deployment of shared ubicomp technologies in the real world. 相似文献
86.
Elaine Y. Chan Author Vitae Author Vitae Michael K. Ng Author Vitae Joshua Z. Huang Author Vitae 《Pattern recognition》2004,37(5):943-952
One of the main problems in cluster analysis is the weighting of attributes so as to discover structures that may be present. By using weighted dissimilarity measures for objects, a new approach is developed, which allows the use of the k-means-type paradigm to efficiently cluster large data sets. The optimization algorithm is presented and the effectiveness of the algorithm is demonstrated with both synthetic and real data sets. 相似文献
87.
88.
FULL-RCMA: a high utilization EPON 总被引:3,自引:0,他引:3
Chuan Heng Foh Andrew L. Elaine Wong Zukerman M. 《Selected Areas in Communications, IEEE Journal on》2004,22(8):1514-1524
This paper proposes an alternate solution for Ethernet passive optical networks. Our solution uses a novel protocol named full utilization local loop request contention multiple-access protocol to efficiently provide communications in passive optical networks. We study the physical layer implementation, as well as medium access control (MAC) layer protocol performance to illustrate the feasibility and benefit of our solution. The performance studies show that the MAC protocol is capable of offering 95% channel utilization under heavy load conditions. The performance results also indicate that delivery of multimedia traffic with a high quality-of-service can be achieved with our solution. 相似文献
89.
Rasmussen Carmen; Ho Elaine; Nicoladis Elena; Leung Joyce; Bisanz Jeffrey 《Canadian Metallurgical Quarterly》2006,60(1):60
Chinese-speaking children have been shown to have an advantage over English-speaking children in a variety of mathematical areas, including counting. One possible explanation for the advantage in counting is that the Chinese number-naming system is relatively transparent, compared to English, in that number names typically are directly indicative of base-10 structure (e.g., 12 is named "ten-two" rather than "twelve"). To determine whether the transparency of the Chinese number-naming system influences counting in bilingual children, we tested 25 Chinese-English bilingual children between the ages of 3 and 5 years, both in English and in Chinese. Children were asked to count as high as they could (abstract counting) and also to count objects in small, medium, and large arrays (object counting). No evidence was found for transparency or for transfer from one language to the other. Instead, relative proficiency in the two languages influenced counting skill. These results are discussed in terms of linguistic and cultural variables that might account for cross-linguistic differences in counting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Vaughan Elaine; Anderson Craig; Agran Phyllis; Winn Diane 《Canadian Metallurgical Quarterly》2004,23(3):289
Interview data from 100 lower income Hispanic and 50 White mothers from a nutritional service clinic extended prior research on cultural differences in the risk for unintentional pediatric injuries. Group differences were expected in reported injury incidence and in the prevalence and impact of contributing factors. As predicted, White mothers reported more injuries for a young child, and among Hispanic mothers, English language preference and use were associated with more reported injuries. Hierarchical regression analysis revealed that risky behaviors, mother's judgment about child compliance, and stressful life events were better predictors of injuries than housing quality, but among Hispanics, the impact of certain factors (e.g.. child temperament) was qualified by mother's acculturation level. Stress and child temperament explained injury differences between more- and less-acculturated Hispanic families but only partially accounted for differences between White mothers and less-acculturated Hispanics. Pediatric injury risk and protective factors seemed to operate in concert with cultural processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献