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排序方式: 共有248条查询结果,搜索用时 31 毫秒
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Grimm EL Brideau C Chauret N Chan CC Delorme D Ducharme Y Ethier D Falgueyret JP Friesen RW Guay J Hamel P Riendeau D Soucy-Breau C Tagari P Girard Y 《Bioorganic & medicinal chemistry letters》2006,16(9):2528-2531
Leukotriene biosynthesis inhibitors have potential as therapeutic agents for asthma and inflammatory diseases. A novel series of substituted coumarin derivatives has been synthesized and the structure-activity relationship was evaluated with respect to their ability to inhibit the formation of leukotrienes via the human 5-lipoxygenase enzyme. 相似文献
203.
Roy C Li T Krasik P Gilbert MJ Pelletier C Gagnon D Robert E Ducharme J Storer R Lavallée JF 《Bioorganic & medicinal chemistry letters》2002,12(21):3141-3143
Several novel racemic aminotetralin derivatives have been prepared using a stereoselective aziridine ring opening reactions and were evaluated for their micro-opioid receptor binding affinity. Selectivity index towards other opioid receptors and antinociceptive activity in mice have been evaluated for the most potent derivatives. 相似文献
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Depending on geographical location, plants are exposed to variable amounts of UVB radiation and herbivore attack. Because the role(s) of UVB in the priming and/or accumulation of plant defence metabolites against herbivores are not well understood, we used field‐grown Nicotiana attenuata plants to explore the effects of UVB on herbivore performance. Consistent with previous reports, UVB‐exposed plants accumulated higher levels of ultraviolet (UV)‐absorbing compounds (rutin, chlorogenic acid, crypto‐chlorogenic acid and dicaffeoylspermidine). Furthermore, UVB increased the accumulation of jasmonic acid, jasmonoyl‐L‐isoleucine and abscisic acid, all phytohormones which regulate plant defence against biotic and abiotic stress. In herbivore bioassays, N. attenuata plants experimentally protected from UVB were more infested by mirids in three consecutive field seasons. Among defence metabolites measured, 17‐hydroxygeranyllinalool diterpene glycosides (HGL‐DTGs) showed strongly altered accumulation patterns. While constitutive HGL‐DTGs levels were higher under UVB, N. attenuata plants exposed to mirid bugs (Tupiocoris notatus) had still more HGL‐DTGs under UVB, and mirids preferred to feed on HGL‐DTGs‐silenced plants when other UVB protecting factors were eliminated by UVB filters. We conclude that UVB exposure not only stimulates UV protective screens but also affects plant defence mechanisms, such as HGL‐DTGs accumulation, and modulates ecological interactions of N. attenuata with its herbivores in nature. 相似文献
207.
Lindsay A. Wilson Malia SQ. Murphy Robin Ducharme Kathryn Denize Nafisa M. Jadavji Beth Potter 《Expert review of proteomics》2013,10(9):727-731
ABSTRACTIntroduction: Preterm birth is a major global health concern, contributing to 35% of all neonatal deaths in 2016. Given the importance of accurately ascertaining estimates of preterm birth and in light of current limitations in postnatal gestational age (GA) estimation, novel methods of estimating GA postnatally in the absence of prenatal ultrasound are needed. Previous work has demonstrated the potential for metabolomics to estimate GA by analyzing data captured through routine newborn screening.Areas covered: Circulating analytes found in newborn blood samples vary by GA. Leveraging newborn screening and demographic data, our group developed an algorithm capable of estimating GA postnatally to within approximately 1 week of ultrasound-validated GA. Since then, we have built on the model by including additional analytes and validating the model’s performance through internal and external validation studies, and through implementation of the model internationally.Expert opinion: Currently, using metabolomics to estimate GA postnatally holds considerable promise but is limited by issues of cost-effectiveness and resource access in low-income settings. Future work will focus on enhancing the precision of this approach while prioritizing point-of-care testing that is both accessible and acceptable to individuals in low-resource settings. 相似文献
208.
Steven Hawken Jeffrey C. Kwong Shelley L. Deeks Natasha S. Crowcroft Robin Ducharme Douglas G. Manuel Kumanan Wilson 《PloS one》2013,8(12)
Objective
We investigated the association between a child''s birth order and emergency room (ER) visits and hospital admissions following 2-,4-,6- and 12-month pediatric vaccinations.Methods
We included all children born in Ontario between April 1st, 2006 and March 31st, 2009 who received a qualifying vaccination. We identified vaccinations, ER visits and admissions using health administrative data housed at the Institute for Clinical Evaluative Sciences. We used the self-controlled case series design to compare the relative incidence (RI) of events among 1st-born and later-born children using relative incidence ratios (RIR).Results
For the 2-month vaccination, the RIR for 1st-borns versus later-born children was 1.37 (95% CI: 1.19–1.57), which translates to 112 additional events/100,000 vaccinated. For the 4-month vaccination, the RIR for 1st-borns vs. later-borns was 1.70 (95% CI: 1.45–1.99), representing 157 additional events/100,000 vaccinated. At 6 months, the RIR for 1st vs. later-borns was 1.27 (95% CI: 1.09–1.48), or 77 excess events/100,000 vaccinated. At the 12-month vaccination, the RIR was 1.11 (95% CI: 1.02–1.21), or 249 excess events/100,000 vaccinated.Conclusions
Birth order is associated with increased incidence of ER visits and hospitalizations following vaccination in infancy. 1st-born children had significantly higher relative incidence of events compared to later-born children. 相似文献209.
目的:研究硫化砷(As4S4)作用于人类急性T细胞白血病细胞株Jurkat细胞后对其增殖的影响及机制。方法:用不同浓度硫化砷(0,2.5,5,10,20txM)作用于Jurkat细胞不同时间(24,48,72小时),通过四甲基偶氮唑蓝(MTT)法观察对其增殖的抑制作用。倒置显微镜下观察不同浓度硫化砷(0,5,10,20txM)作用Jurkat细胞24小时后细胞数目和形态变化。利用Westemblot方法检测硫化砷(0,5,10uM)作用Jurkat细胞24小时后胞内CleavedNotchl蛋白和C.myc蛋白变化情况。结果:@MTT结果提示硫化砷在一定浓度范围内对Jurkat细胞有明显的抑制作用(P〈0.05),并呈浓度和时间依赖性。②显微镜下观察到硫化砷处理Jurkat细胞24小时后,细胞数目随药物浓度增加而减少,而其细胞碎片随着药物浓度增加而增加。@Westernblot结果显示硫化砷处理24小时后,胞内CleavedNotchl蛋白、C-myc蛋白下调,并随浓度增加下降的更为明显。结论:硫化砷对Jurkat细胞生长具有抑制作用.其机制可能通过影响Notch信号通路起作用。 相似文献
210.
Dakota L. Jones Jeffrey A. Meridew Patrick A. Link Merrick T. Ducharme Katherine L. Lydon Kyoung M. Choi Nunzia Caporarello Qi Tan Ana Maria Diaz Espinosa Yuning Xiong Jeong-Heon Lee Zhenqing Ye Huihuang Yan Tamas Ordog Giovanni Ligresti Xaralabos Varelas Daniel J. Tschumperlin 《The Journal of cell biology》2021,220(5)