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排序方式: 共有642条查询结果,搜索用时 15 毫秒
61.
Daniel J. O’Shannessy Stephen M. Jackson Natalie C. Twine Bryan E. Hoffman Zoltan Dezso Sergei I. Agoulnik Elizabeth B. Somers 《International journal of molecular sciences》2013,14(7):13687-13703
Folate receptor alpha (FOLR1/FRA) is reported to be overexpressed in epithelial ovarian cancers (EOC), especially the serous histotype. Further, while dysregulation of the folate-dependent 1-carbon cycle has been implicated in tumorogenesis, little is known relative to the potential mechanism of action of FOLR1 expression in these processes. We therefore investigated the expression of FOLR1, other folate receptors, and genes within the 1-carbon cycle in samples of EOC, normal ovary and fallopian tube on a custom TaqMan Low Density Array. Also included on this array were known markers of EOC such as MSLN, MUC16 and HE4. While few differences were observed in the expression profiles of genes in the 1-carbon cycle, genes previously considered to be overexpressed in EOC (e.g., FOLR1, MSLN, MUC16 and HE4) showed significantly increased expression when comparing EOC to normal ovary. However, when the comparator was changed to normal fallopian tube, these differences were abolished, supporting the hypothesis that EOC derives from fallopian fimbriae and, further, that markers previously considered to be upregulated or overexpressed in EOC are most likely not of ovarian origin, but fallopian in derivation. Our findings therefore support the hypothesis that the cell of origin of EOC is tubal epithelium. 相似文献
62.
Natalie Chun 《国际水资源开发杂志》2014,30(4):662-679
Pricing policies can serve as a low-cost and effective tool for increasing access to water and sanitation services among poor households while allowing the provider to recover costs. An empirical model is applied to contingent-valuation survey data for water services in Cebu, Philippines. Pricing policies that utilizes a low one-time connection fee and differentiates tariffs based on wealth results in a 3 to 9-fold increase in water services access by poor households over the base pricing policy. The results provide evidence that price-discrimination techniques can be important tools toward achieving greater coverage and financial solvency of important services. 相似文献
63.
Glass-Related Injuries in Oklahoma City Bombing 总被引:2,自引:0,他引:2
H. Scott Norville Natalie Harvill Edward J. Conrath Sheryll Shariat Sue Mallonee 《Canadian Metallurgical Quarterly》1999,13(2):50-56
When a terrorist bomb explodes in an urban area, it produces devastating effects, including structural and nonstructural damage to buildings, injuries, and deaths. Numerous injuries in explosions result directly and indirectly from window glass failure. Direct glass-related injuries occur when glass shards flying and falling from fractured windows cause lacerations and abrasions. Secondary glass-related injuries occur when the shock front of the blast wave passes into buildings through fenestrations vacated by fractured glazing. The Oklahoma city bombing killed 167 people and caused numerous injuries. Most of the deaths and many of the injuries occurred in the Alfred P. Murrah Federal Building, the target of the bomb. This event focused the attention of the engineering and security communities on two major issues: the prevention of progressive structural collapse and the design of blast-resistant glazing. This paper discusses glass-related injuries that occurred away from the Alfred P. Murrah Federal Building in Oklahoma City. In particular, it provides information concerning locations of glass-related injury victims in other buildings with respect to their position in proximity to outside walls with glazing. Location data indicate that more than one-quarter of the glass-related injury victims in buildings were positioned within 1.5 m (5 ft) of a wall with glazed fenestrations and nearly one-half of the glass-related injury victims were positioned within 3.0 m (10 ft) of a wall with glazed fenestrations. In addition to suffering lacerations and abrasions, a large number of victims in buildings suffered hearing damage because glazing that failed to maintain closure of fenestrations exposed them to the shock front of the blast wave. Consideration of the injury data justifies a requirement for design of blast-resistant glazing to protect building inhabitants. 相似文献
64.
65.
业务模式的缺陷、运营商的谨慎及标准的冲突阻碍了手机电视发挥其真正的潜力。由于媒体公司很快就获得了其移动性法案(或有或无电信公司的支持),因此这项技术将引领用户驱动的视频革命。 相似文献
66.
Fastenau Philip S.; Denburg Natalie L.; Domitrovic Lidia A. 《Canadian Metallurgical Quarterly》1997,28(1):32
Clinicians sometimes worry that the administration of intentional memory tests early in a clinical battery might artificially enhance performance on subsequent incidental memory tests, with possible differential effects for younger vs. older adults. Eighty-one healthy adults (ages 30–80) were blindly assigned to 1 of 2 testing conditions (incidental followed by intentional and vice versa). Contrary to the concerns of some, administration of intentional tests prior to incidental tests did not affect performance on any measures, and there was no interaction with age. Order of administration did not affect performance in older or younger adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Whereas psychological assessment remains a critical skill, it can demand considerable time and effort. In fact, it can often feel tedious and even laborious. As a partial outgrowth, short forms in psychological testing are intrinsically appealing. Unfortunately, many concerns can be raised regarding this practice. This article represents a response to A. P. Thompson, S. G. LoBello, L. Atkinson, V. Chisholm, and J. J. Ryan (see record 2004-95164-011) and is intended to strengthen the discussion on this practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Natalie Stoeckl Michelle Esparon Marina Farr Aurélie Delisle Owen Stanley 《Papers in Regional Science》2014,93(4):783-801
This empirical study explores financial links between indigenous and non‐indigenous economic systems in a remote river catchment in Northern Australia (the Mitchell). It finds evidence of a profound and asymmetric ‘disconnect’ between these economies: an exogenous increase in indigenous incomes raises the incomes of non‐indigenous people, but the reverse is not true. Evidently, those seeking to improve the incomes of indigenous people in Northern Australia cannot simply seek to (i) increase payments to indigenous people, or (ii) expand the non‐indigenous sector hoping that some benefits will ‘trickle down’. Instead, structural change is required. 相似文献
69.
Internal Magnetic Structure of Nanoparticles Dominates Time‐Dependent Relaxation Processes in a Magnetic Field
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70.
Sarah R. Cowan Wei Lin Leong Natalie Banerji Gilles Dennler Alan J. Heeger 《Advanced functional materials》2011,21(16):3083-3092
Small amounts of impurity, even one part in one thousand, in polymer bulk heterojunction solar cells can alter the electronic properties of the device, including reducing the open circuit voltage, the short circuit current and the fill factor. Steady state studies show a dramatic increase in the trap‐assisted recombination rate when [6,6]‐phenyl C84 butyric acid methyl ester (PC84BM) is introduced as a trap site in polymer bulk heterojunction solar cells made of a blend of the copolymer poly[N‐9″‐hepta‐decanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole) (PCDTBT) and the fullerene derivative [6,6]‐phenyl C61 butyric acid methyl ester (PC60BM). The trap density dependent recombination studied here can be described as a combination of bimolecular and Shockley–Read–Hall recombination; the latter is dramatically enhanced by the addition of the PC84BM traps. This study reveals the importance of impurities in limiting the efficiency of organic solar cell devices and gives insight into the mechanism of the trap‐induced recombination loss. 相似文献