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Expression and function of heregulin-α and its receptors in the mouse mammary gland

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science china(Life sciences) 2010年第8期53卷 1015-1024页

作者： GENG LiJing1 & LI QingZhang2 1Institute of Food science and Engineering, Liaoning Medical university, Jinzhou 121000, china 2Key Laboratory of Dairy science of Ministry of Education, Northeast agricultural university, Harbin 150030, china 1. Institute of Food science and Engineering Liaoning Medical University Jinzhou 121000 China2. Key Laboratory of Dairy Science of Ministry of Education Northeast Agricultural University Harbin 150030 China

Heregulin-α (HRGα) is a cytokine secreted by the mammary mesenchyme, adjacent to lobuloalveolar structures. To understand the role of HRGα and its receptors in mammary glands, and the underlying mechanisms, we performed this study to determine the expression and localization of HRGα and its receptors ErbB2 and ErbB3. We also determined the role of HRGα in the development of mammary glands, β-casein expression and secretion, Rab3A protein expression and the phosphorylation of HRGα signaling molecules using confocal laser scanning microscopy, tissue culture, capillary electrophoresis, Western blotting and enzyme-linked immunosorbent assays. We found that a peak was on pregnancy day 15. Changes of ErbB2 and ErbB3 expression were positively and linearly correlated with HRGα, indicating that HRGα positively regulates ErbB2 and ErbB3 expression. During pregnancy, HRGα enhanced the phosphorylation of STAT5, p42/p44, p38, PKC and Rab3A protein expression, stimulated the proliferation and differentiation of the ductal epithelial cells of mammary glands, and increased and maintained the expression and secretion of β-casein. During lactation, HRGα enhanced the phosphorylation of STAT5 and p38, inhibited the phosphorylation of PKC and Rab3A protein expression, maintained the morphology of the mammary glands and increased the secretion of lactoprotein to reduce the expression of β-casein in mammary epithelial cells. During involution, HRGα induced the phosphorylation of STAT3 and Rab3A protein expression, and inhibited the phosphorylation of PKC to stimulate the degeneration of mammary epithelial cells. It also inhibited the secretion of β-casein, resulting in increased levels of β-casein in mammary epithelial cells.

关键词： mammary gland heregulin-α ErbB2 ErbB3 signal transduction

Anthropogenic Impacts on the Sediment Flux in the Dry-hot Valleys of Southwest china—an Example of the Longchuan River

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Journal of Mountain science 2004年第3期1卷 239-249页

作者： ZHOUYue LUXixi HUANGYing ZHUYunmei facultyofEnvironmentalscienceandEngineering KunmingUniversityofScienceandTechnologyKunming650093China DepartmentofGeography UniversityofSingapore10KentRidgeCrescent119260Singapore BureauofHydrologyandWaterResourcesofyunnanProvince Kunming650093China

The sediment flux data, measured from a dry-hot valley of the Longchuan River, a tributary of the lower Jinsha River, were analyzed with Mann-Kendall test, Seasonal Mann-Kendall test and Sen’s test. In both the upper reaches (Xiaohekou) and the lower reaches (Xiaohuangguayuan), the sediment fluxes showed a significant increase from 1970 to 2001, despite the fact that the water discharge did not change significantly during the period and numerous reservoir constructions which contribute to the trap of sediment. This can be attributed to the intensification of human activities, especially the activities related to land surface disturbances such as deforestation and afforestation, expansion of agriculture land, and road constructions. This increase is more significant in the lower reaches of the river observed at the place of Xiaohuangguayuan due to the dry-hot climate. The profound increase in sediment flux has significant implications for effective management of the sedimentation problems of the on-going Three Gorges Reservoir.

关键词： Sediment flux dry-hot valley deforestation afforestation reservoir road construction

Composite Cathode Bi_(1.14)Sr_(0.43)O_(2.14)-Ag for Intermediate-temperature Solid Oxide Fuel Cells

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Journal of Wuhan university of technology(Materials science) 2008年第3期23卷 350-353页

作者：高展张萍 faculty of Material science and Chemical Engineering China University of Geosciences

Composites consisting of strontium stabilized bismuth oxide （Bi1.14Sr0.43O2.14, SSB） and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There were no chemical reactions between the two components. The microstructure of the interfaces between composite cathodes and Ce0.8Sm0.2O1.9 （SDC） electrolytes was examined by scanning electron microscopy （SEM）. Impedance spectroscopy measurements show that the performance of cathode fired at 700 ℃ is the best. When the content of Ag2O is 70 wt%, polarization resistance values for the SSB-Ag cathodes are as low as 0.2 Ωcm^2 at 700℃ and 0.29 Ωcm^2 at 650℃. These results are much smaller than some of other reported composite cathodes on doped ceria electrolyte and indicate that SSB-Ag composite is a potential cathode material for intermediate temperature SOFCs.

关键词： solid oxide fuel cells (SOFCs) composite cathode strontium stabilized bismuth oxide (SSB) samaria doped ceria (SDC)

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 College of Resources and Environmental science, Nanjing agricultural university, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China College of Resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Hydrothermal Synthesis,Crystal Structure and Properties of Inorganic-Organic Hybrid Materials Based on Diphosphopentamolybdate

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Journal of Wuhan university of technology(Materials science) 2008年第3期23卷 407-410页

作者：靳素荣 School of science Wuhan University of Technology

The compound of diphosphopentamolybdate { [Cu（en）（Hen）]2[P2Mo5O23] }·3H2O [en=ethylenediamine] had been obtained from the hydrothermal method and characterized by single crystal X-ray diffraction, elemental analysis, FT-IR, and thermogravimetric analysis The structure consist of [P2Mo5O23]^6- clusters anions, complex [Cu（en）（Hen）]^3＋ cations and crystallization water molecules, which are held together to a two-dimensional framework The most interesting feature of the compound is that two nitrogen atoms are both coordinated with Cu（ Ⅱ ） in one ethylenediamine molecule, for the other ethylenediamine molecule, only one nitrogen atom is towards Cu（ Ⅱ） and the other nitrogen atom is protonated and formed Hen^＋.

关键词： polyoxometalate hydrothermal synthesis crystal structure coordination groups

Search for B_c (ns) via the B_c (ns) → B_c (ms) π^+ π^- transition at LHCb and Z^0 factory

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science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2019-2024页

作者： KE HongWei 1 & LI XueQian 2 1 School of science,Tianjin university,Tianjin 300072,china 2 School of Physics,Nankai university,Tianjin 300071,china 1. School of science Tianjin University Tianjin 300072 China2. School of Physics Nankai University Tianjin 300071 China

It is interesting to study the characteristics of the whole family of B c which contains two different heavy *** and the proposed Z 0 factory provide an opportunity because a large database of the B c family will be achieved.B c and its excited states can be identified via their decay *** suggested by experimentalists,B-c (ns) → B c +γ is not easy to be clearly measured,instead,the trajectories of π + and π- occurring in the decay of B c (ns) → B c (ms) + π + π( n > m ) can be unambiguously identified,thus the measurement seems easier and more reliable;therefore this mode is more favorable at the early running stage of LHCb and the proposed Z 0 *** this work,we calculate the rate of B c (ns) → B c (ms) + π + π-in terms of the QCD multipole-expansion and the numerical results indicate that the experimental measurements with the luminosity of LHC and Z 0 factory are feasible.

关键词： meson hadronic decay QCD multipole-expansion

A membrane-tethered transcription factor ANAC089 negatively regulates floral initiation in Arabidopsis thaliana

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science china(Life sciences) 2010年第11期53卷 1299-1306页

作者： LI JianQin1,2, ZHANG Juan1, WANG XueChen1 & CHEN Jia1 1 State Key Laboratory of Plant Physiology and Biochemistry,College of Biological sciences, china agricultural university, Beijing 100193, china 2 College of Life science and technology, Guangxi university, Nanning 530005, china 1. State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100193 China2. College of Life Science and Technology Guangxi University Nanning 530005 China

The plant-specific NAC (NAM, ATAF1/2,and CUC2) transcription factors have a regulatory function in developmental processes and stress responses. Notably a group of NAC members named NTLs (NTM1-Like) are membrane-tethered, ensuring plants rapidly respond to developmental changes and environmental stimuli. Our results indicated that ANAC089 was a membrane-tethered transcription factor and its truncated form was responsible for the physiological function in flowering time control.

关键词： Arabidopsis thaliana ANAC089 floral initiation membrane-tethered transcription factor

EFFECT OF NITROGEN ON MATRIX STRUCTURE OF GRAY CAST IRON

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Acta Metallurgica Sinica(English Letters) 1993年第6期6卷 370-372页

作者： ZHAI Qijie HU Hanqi university of science and technology Beijing,china associate professor,faculty of Foundry,university of science and technology Beijing,Beijing 100083,china

Effect of nitrogen on matrix structure of 3 different varieties of gray cast iron,i.e., sub-eutectic Fe-C-Si,near-eutectic Fe-C-Si and Fe-C-Si-Mn,has been investigated. The eutectie colony structure of gray cast iron may be refined,the pearlite content increased and the micro-hardness of pearlite and ferrite raised with an addition of *** influ- ence of nitrogen on the transformation temperature of the equilibrium and non-equilibrium phases,as well as,the solution of nitrogen in ferrite and cementite seem to be the major rea- sons to strengthening the matrix structure of gray cast iron.

关键词： nitrogen gray cast iron matrix structure microhardness solid solution

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衰老或肿瘤：癌基因诱导的双向性

生物化学与生物物理进展 2009年第12期36卷 1530-1535页

作者：司晓宇罗瑛昆明理工大学生命科学与技术学院、衰老与肿瘤分子遗传学实验室昆明650224

在大部分的肿瘤中都发现有癌基因的活化,癌基因的活化被认为是导致肿瘤发生的重要原因.然而,在野生型细胞内,癌基因的活化可以诱导细胞衰老,称为癌基因诱导的细胞衰老(oncogene-induced senescence,OIS),从而抑制进一步的肿瘤发生.因而... 详细信息

在大部分的肿瘤中都发现有癌基因的活化,癌基因的活化被认为是导致肿瘤发生的重要原因.然而,在野生型细胞内,癌基因的活化可以诱导细胞衰老,称为癌基因诱导的细胞衰老(oncogene-induced senescence,OIS),从而抑制进一步的肿瘤发生.因而,癌基因的活化具有诱导衰老或肿瘤的双向性.DNA损伤调控反应(DNA damage checkpoint response,DDR)是细胞应对DNA损伤时感应损伤,从而延迟或阻滞细胞周期进程的一种分子信号传递通路,是诱导细胞衰老的重要机制.癌基因的活化可以引发DNA损伤信号的产生,从而激活DDR,诱导细胞衰老.在DDR异常时,癌基因的激活可引发DNA的过度复制与细胞的过度增殖,并导致基因组不稳定性的积累,最终导致肿瘤发生.DDR的完整性决定了癌基因诱导的双向性.DDR在癌基因诱导中的重要作用,提示了保持和恢复DDR的完整性可以作为肿瘤预防和治疗的新方向.

关键词：癌基因细胞衰老癌基因诱导的衰老 DNA损伤调控反应 DNA过度复制