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701.
Liu DaZhen Yin CaiHua Zhang YingMei Tian LinJie Li Ting Li Dan Ma DaLong Guo YingLu Wang Ying 《科学通报(英文版)》2009,54(6):1050-1057
CKLF (chemokine-like factor)-like MARVEL (MAL and related proteins for vesicle trafficking and membrane link domain) transmembrane
domain containing (CMTM) is a novel gene family. One member of this family, CMTM2, also named chemokine-like factor superfamily
2 (CKLFSF2), is expressed highly in the testis and moderately in the prostate, marrow and peripheral blood cells. However,
the function of human CMTM2 remains unknown. Here, we found that CMTM2 was upregulated in 5α-dihydrotestosterone (DHT)-treated
LNCaP cells. We investigated the relationship between CMTM2 and the androgen receptor. Our results showed that CMTM2 enhanced
DHT-mediated androgen receptor (AR) transactivation and the expression of prostate specific antigen (PSA). We also observed
that CMTM2 enhanced the AR protein level, which was reversed by silencing endogenous CMTM2 expression, which suggested that
CMTM2 might play an important role in maintaining the AR protein level. We also found that CMTM2 suppressed Akt activation.
A previous study showed that Akt could phosphorylate AR at Ser210 and Ser790 and lead to AR ubiquitylation and degradation
as well as suppression of AR activity. Taken together, suppressing Akt activation and increasing the AR protein level might
be one of the mechanisms for the CMTM2-mediated enhancement of AR transactivation.
Supported by National High Technology Research and Development Program of China (Grant Nos. 2006AA02A305 and 2002BA711A01)
and National Natural Science Foundation of China (Grant Nos. 30271203 and 30671907) 相似文献
702.
X-ray powder diffraction is an indispensable technique to study material structure, phase transition and so on. It is necessary for high quality diffraction data to get high-precision diffraction angle. This work proposed four corrected functions of X-ray powder diffraction angle. Two methods, linearization method and modified Levenberg-Marquardt iteration method, are given to solve the function parameters, and the modified Levenberg-Marquardt method has fast convergent speed and stable solution. Two methods can give closed parameters, including those of Lu, Liu, and Chu functions and polynomial. New-corrected functions were used to fit the diffraction angle error of the tetragonal rutile polycrystalline TiO2 mixed with Gd0.45Y2.55Sc2Ga3O12 as a standard sample, and the computation result indicates that these functions can characterize the diffraction error very well. In some cases, the new-corrected functions can describe the diffraction angle error better than the reported corrected functions. At the same time, the lattice parameter of Gdo.45Y2.55Sc2Ga3O12 was computed with two methods. When the corrected function parameters and lattice parameters were solved by the least square method, the interaction of the function parameters and lattice parameters would result in great error. However, when the X-ray diffraction angles were corrected by corrected functions using a standard sample, the authentic lattice parameters can be obtained by the least square fitting. 相似文献
703.
热暴露过程中7050铝合金的微观组织与性能的研究 总被引:1,自引:1,他引:0
采用透射电子显微镜和拉伸实验研究了不同热暴露条件下7050-T7651铝合金微观组织和拉伸力学性能.结果表明:未经热暴露的7050-T7651铝合金中主要析出相为Guinierprestonzone(GP区)和η′相,其中η′相与基体的取向关系为[0001]η′//[11]Al,(100)η′//(110)Al.随后7050-T7651铝合金在不同温度下分别热暴露500h,随着热暴露温度的提高,合金中析出相长大越明显,晶界附近无沉淀析出带(PFZ)宽化也越明显 热暴露温度提高,合金强度下降越多.7050-T7651铝合金经过长时间热暴露后强度下降、塑性提高的主要原因是晶内主要强化相GP区和η′相的长大粗化以及晶界附近无沉淀析出带(PFZ)宽化. 相似文献
704.
采用离子交换法将不同组份的十烷基三丁基溴化鳞交换到蒙脱土的层间得到柱撑蒙脱土.用热重分析(TGA)、X-射线衍射(XRD)和傅里叶变换红外光谱法(FTIR)等对其结构进行了表征,并测定其抗菌活性.研究发现柱撑蒙脱土中季鳞盐的热分解起始温度大于210℃,具有较好的热稳定性;季鳞盐含量越高,柱撑蒙脱土的层间距越大,抗菌活性越高. 相似文献
705.
乙烯深冷分离工艺中LNG冷能利用的可行性 总被引:1,自引:0,他引:1
充分利用液化天然气(LNG)携带的冷量,不仅可降低下游天然气供气成本,还可减少LNG汽化带来的环境污染;传统乙烯深冷分离工艺需压缩制冷系统提供不同温位的冷量分离裂解气,消耗大量压缩功耗.将LNG冷量用于30万吨/年乙烯装置的深冷分离工艺,取代部分压缩制冷负荷的集成利用研究结果表明:LNG冷量在乙烯分离工艺中的利用率达76.5%,可替代原工艺中的冷量负荷约22472 kW,节省丙烯、乙烯、甲烷冷剂三机压缩制冷的功耗约11968 kW,大大降低乙烯装置的能耗成本.但LNG冷量仅与乙烯分离工艺集成,传热过程火用效率较低,建议将LNG冷量集成利用于两种或以上冷量利用工艺中,从而减少利用过程的冷火用损失,提高LNG冷量的利用效率. 相似文献
706.
707.
708.
The Zhangcunping area is located at the north limb of the Huangling anticline in Yichang, Hubei Province. Here, the sedimentary
succession of the Ediacaran Doushantuo Formation is similar with that in the Weng’an area, Guizhou Province. A large number
of new microfossils (mainly acanthoacritarchs) from the Doushantuo Formation in this area are reported in this paper. The
fossil assemblage shows similarity as the phosphatized biota of the Doushantuo Formation at Weng’an, Guizhou Province and
the silicified biota of the Doushantuo Formation at the Yangtze Gorges, which suggests that the Zhangcunping area is a key
for correlation of the Doushantuo Formation between the Weng’an area, Guizhou Province and the Yangtze Gorges. Besides, a
new zircon SHRIMP U-Pb age (614.0±7.6 Ma) is first obtained from a horizon underneath the exposed surface in the middle of
the Doushantuo Formation in the Zhangcunping area. This age not only provides a new datum for subdivision of the Ediacaran
Doushantuo Formation, but also indicates that the age of the exposed surface in the middle of the Doushantuo Formation in
the Yangtze Platform should be posterior to 614.0±7.6 Ma. Due to the horizon of the Weng’an biota situated above the exposed
surface, the age of the Weng’an biota should be posterior to 614.0±7.6 Ma as well.
Supported jointly by the Basic Foundation of scientific research work from Ministry of Science and Technology of the People’s
Republic of China (Grant No. J0716), Science and Technology of China for fundamental work (Grant No. 2006FY120300-2), National
Natural Science Foundation of China (Grant Nos. 40772013 and 40672022) and China Geological Survey (1212010611801-3) 相似文献
709.
"Steiner trees" between cell walls of sisal 总被引:1,自引:0,他引:1
Through careful analysis on the cross-section of sisal fibers, it is found that the middle lamellae between the cell walls have clear geometric characteristics: between the cell walls of three neighboring cells, the middle lamellae form a three-way junction with 120° symmetry. If the neighboring three-way junctions are connected, a network of Steiner tree with angular symmetry and topological invariability is formed. If more and more Steiner trees are connected, a network of Steiner rings is generated. In another word, idealized cell walls and the middle lamellae are dominated by the Steiner geometry. This geometry not only depicts the geometric symmetry, the topological invariability and minimal property of the middle lamellae, but also controls the mechanics of sisal fibers. 相似文献
710.