期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
冀东黑云母片麻岩在1GPa压力下脱水熔融实验 被引量:10
1
作者 吴宗絮 邓晋福 《地质科学》 CAS CSCD 北大核心 1995年第1期12-18,共7页
报道冀东黑云母片麻岩在1GPa压力下脱水熔融实验的相关系。其固相线温度为812℃,黑云母消失的温度为837℃,角闪石消失的温度为887℃,在862℃时开始形成斜方辉石和单斜辉石。实验表明,在温度812—950℃范围内... 报道冀东黑云母片麻岩在1GPa压力下脱水熔融实验的相关系。其固相线温度为812℃,黑云母消失的温度为837℃,角闪石消失的温度为887℃,在862℃时开始形成斜方辉石和单斜辉石。实验表明,在温度812—950℃范围内形成水不饱和的花岗质岩浆,数量为20%-30%,而留下的难熔残余是斜方辉石+单斜辉石+石榴石+斜长石+石英±角闪石,后者与麻粒岩相岩石的矿物组合相符合,暗示下地壳岩石经生成花岗质熔浆的熔融事件后,留下的将是麻粒岩相岩石。 展开更多
关键词 片麻岩 黑云母 1gpa 压力 脱水 熔融实验
在线阅读 下载PDF
Three New Hydroxytetradecenals from Amomum tsao-ko with Protein Tyrosine Phosphatase 1B and Glycogen Phosphorylase Inhibitory Activity
2
作者 Xiaolu Qin Xinyu Li +6 位作者 Yi Yang Mei Huang Shengli Wu Pianchou Gongpan Lianzhang Wu Juncai He Changan Geng 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期875-883,共9页
The fruits of Amomum tsao-ko(Cao-Guo)were documented in Chinese Pharmacopoeia for the treatment of abdominal pain,vomiting,and plague.In our previous study,a series of diarylheptanes and flavonoids withα-glucosidase ... The fruits of Amomum tsao-ko(Cao-Guo)were documented in Chinese Pharmacopoeia for the treatment of abdominal pain,vomiting,and plague.In our previous study,a series of diarylheptanes and flavonoids withα-glucosidase and protein tyrosine phosphatase 1B(PTP1B)inhibitory activity have been reported from the middle-polarity part of A.tsao-ko,whereas the antidiabetic potency of the low-polarity constituents is still unclear.In this study,three new hydroxytetradecenals,(2E,4E,8Z,11Z)-6R-hydroxytetradeca-2,4,8,11-tetraenal(1),(2E,4E,8Z)-6R-hydroxytetradeca-2,4,8-trienal(2)and(2E,4E)-6R-hydroxytetradeca-2,4-dienal(3)were obtained from the volatile oils of A.tsao-ko.The structures of compounds 1–3 were determined using spectroscopic data involving 1D and 2D nuclear magnetic resonance(NMR),high-resolution mass spectra(HRMS),and specific rotation([α]D).Their hypoglycemic activity was evaluated against glycogen phosphorylase(GPa)and PTP1B.Compounds 1 and 2 displayed moderate activity against PTP1B with inhibition rates of 33.8%−50.3%at 100 and 200μM.Moreover,compound 1 exhibited an obvious inhibitory effect on GPa(IC50=31.7μM),whereas compound 2 was inactive.This study demonstrates hydroxytetradecenals as the characteristic components of A.tsao-ko with therapeutic potential in diabetes. 展开更多
关键词 Cao-Guo PTP1B and GPa inhibitors diabetes mellitus volatile oils
在线阅读 下载PDF
拟南芥G蛋白突变体gpa1-1、gpa1-2形态及生理特性分析
3
作者 史冬燕 陈善娜 +3 位作者 邓国宾 夏小环 徐玲玲 陈小兰 《西南农业学报》 CSCD 2005年第3期260-263,共4页
对拟南芥野生型Ws及其G蛋白α亚基突变体gpa1 1和gpa1 2的形态特征进行了比较,并研究了低温处理对其抗氧化酶系活力和丙二醛含量的差异。结果表明,与野生型相比,两突变体形态上发生了较大的变化,并表现出对低温反应敏感性的降低。低温12... 对拟南芥野生型Ws及其G蛋白α亚基突变体gpa1 1和gpa1 2的形态特征进行了比较,并研究了低温处理对其抗氧化酶系活力和丙二醛含量的差异。结果表明,与野生型相比,两突变体形态上发生了较大的变化,并表现出对低温反应敏感性的降低。低温12h时,野生型的SOD酶和POD酶活迅速发生变化,丙二醛含量迅速升高,而两突变体变化较平缓。 展开更多
关键词 GA Ws gpa1-1 gpa1-2 抗氧化酶系 丙二醛
在线阅读 下载PDF
1 GPa级TRIP型BF钢的组织调控和强塑性机制 被引量:3
4
作者 侯晓英 孙卫华 +5 位作者 金光宇 王业勤 郝亮 曹光明 任东 殷继丽 《材料研究学报》 EI CAS CSCD 北大核心 2020年第10期793-800,共8页
以节约化、经济化、轻量化为立足点,利用"TRIP效应"解决强塑性同步提高的矛盾,制备出一种1 GPa级TRIP型BF钢,研究了不同组织调控的微观形貌和强塑性机制。结果表明,合理的成分设计和将热轧初始组织调控为(20~30)%铁素体和(70~... 以节约化、经济化、轻量化为立足点,利用"TRIP效应"解决强塑性同步提高的矛盾,制备出一种1 GPa级TRIP型BF钢,研究了不同组织调控的微观形貌和强塑性机制。结果表明,合理的成分设计和将热轧初始组织调控为(20~30)%铁素体和(70~80)%针状贝氏体,有利于将最终成品的显微组织调控为(75~85)%BF和≥15%的第二相残γ组织,使1 GPa级TRIP型BF钢具有优良的综合性能。两相组织的合理配比及其形貌特征,对TRIP型BF钢的强塑性有显著的影响。在82%的BF组织基体中均匀分布着片层宽度为80~130 nm的第二相残γ组织,在两相协调变形机制作用下可达到优良的强塑性匹配:延伸率20.3%,强塑积达到22.0 GPa·%;当BF组织板条的宽度为0.15~0.45μm且薄膜状残γ组织的宽度为50~90 nm时,强度达到1099 MPa,发生碰撞时剩余的残γ组织(约6%)发挥"TRIP效应"从而提高防撞件的吸能和安全性。 展开更多
关键词 金属材料 1 GPa级TRIP型BF钢 组织调控 强塑性机制
原文传递
Phosphorylation-activated G protein signaling stabilizes TCP14 and JAZ3 to repress JA signaling and enhance plant immunity
5
作者 Haiyan Jia Natalie Hewitt +10 位作者 Lucía Jordá Tigran M.Abramyan Josh Tolliver Janice L.Jones Kinya Nomura Jing Yang Sheng-Yang He Alexander Tropsha Antonio Molina Henrik G.Dohlman Alan M.Jones 《Molecular Plant》 2025年第7期1171-1192,共22页
The plant hormones salicylic acid(SA)and jasmonic acid(JA)act in mutual negative-feedback regulation to balance plant growth-defense trade-off.Heterotrimeric Gα-Gβ-Gγproteins are hubs that regulate defense signalin... The plant hormones salicylic acid(SA)and jasmonic acid(JA)act in mutual negative-feedback regulation to balance plant growth-defense trade-off.Heterotrimeric Gα-Gβ-Gγproteins are hubs that regulate defense signaling.In Arabidopsis,the Gα(GPA1)and Gβ(AGB1)subunits are required for defense against biotrophic and necrotrophic pathogens;however,the upstream and downstream molecular mechanisms underlying G protein-mediated defense remain largely unclear.In this study,we found that G proteins are primarily negative regulators of JA signaling in response to pathogen attack.Both TCP14 and JAZs are transcriptional regulators in the JA pathways.We revealed that GPA1 interacts with TCP14 within nuclear foci,and AGB1 interacts with TCP14 and most of JAZ regulators,including JAZ3.Mechanistically,GPA1 slows the proteasomal degradation of the G protein-TCP14-JAZ3 complex,a process that is normally promoted by JA and the bacterial virulence effector HopBB1,thus boosting SA-based defense.In turn,GPA1 activity is regulated by JA-induced phosphorylation at a conserved residue located near the nucleotide-binding pocket and other residues within the N-terminalαhelix.The phosphomimic mutations do not affect GTP binding or hydrolysis but enhance GPA1 interaction with TCP14 and JAZ3,thereby preventing their degradation.This newly discovered phosphorylation-dependent mechanism of de-sequestering G protein partners to modulate transcriptional regulation may extend to both yeast and human cells. 展开更多
关键词 heterotrimeric G proteins GPA1 AGB1 AGGs bacterial virulence effector HopBB1 jasmonic acid JA TCP14 disease resistance PHOSPHORYLATION
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部