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71.
Zhang Kun Zhang Yunhai Pan Dengke Ma Yufang Wei Hengxi Zhang Jian Li Xuyang Wang Shaohu Li Yan Dai Yunping Li Ning 《自然科学进展(英文版)》2007,17(10):1172-1176
Seasonal influence on the developmental ability of porcine embryos was studied by comparisons of the number of cumulus-oocytes-complexes (COCs) per ovary pair and meiotic maturation ability of oocytes in different seasons; and by the observations on developmental competence of the parthenogenetic oocytes and cloned embryos collected from different seasons. We found that the number of COCs per ovary pairs was significantly higher in spring compared to the other seasons (P<0.05). However, no significant difference was found in the rate of oocytes progressing to MⅡ in four seasons (P<0.05). In addition, the rate of blastocyst formation of parthenogenetic embryos in summer was obviously declined compared to the other seasons (P<0.05), and an increased blastocyst rate of cloned porcine embryos was found in spring compared to autumn and winter (P<0.05). The results suggest that there should be a seasonal influence on the developmental competence of porcine embryos. 相似文献
72.
MIAO YuChen GUO JingGong LIU ErTao LI Kun DAI Jie WANG PengCheng CHEN Jia SONG ChunPeng 《科学通报(英文版)》2007,52(1):127-130
Gene expression of glutathione peroxidase 3 (ATGPX3) in response to osmotic stress was analyzed in Arabidopsis using ATGPX3 promoter-glucuronidase (GUS) transgenic plants. High levels of GUS ex- pression were detected under osmotic stress in ATGPX3 promoter-GUS transgenic plants. Compared with the wild type, the growth and development of ATGPX3 mutants (atgpx3-1) were more sensitive to mannitol. In addition, the expression of RD29A, ABI1, ABI2 and RbohD in atgpx3-1 was induced by ABA stress. These results suggest that ATGPX3 might be involved in the signal transduction of osmotic stress. 相似文献
73.
Inhibition of PKB/Akt activity involved in apigenininduced apoptosis in human gastric carcinoma cells 总被引:1,自引:0,他引:1
YUAN LinHong XIA Wei ZHAO XiuJuan ZHANG XiaoHua ZHANG Ling WU Kun 《科学通报(英文版)》2007,52(16):2226-2232
Apigenin is a flavonoid widely distributed in fruits and vegetables. It possesses growth inhibitory properties against numerous cancer cell lines. However,the molecular mechanism(s) by which api-genin elicits its effects have not been fully elucidated. Here we studied whether apigenin inhibits growth and induces apoptosis in human gastric carcinoma cells. We showed that the flavonoid inhibited growth of the cells and caused apoptosis,as evidenced by DNA Ladder,cleavage of pro-caspase-3 in a time-dependent manner. Induction of apoptosis was dependent on inhibition of the PKB/Akt activity. We found that while apigenin had no effect on the expression of Akt and Bad,it inhibited specific phosphorylation of the two proteins that are associated with pro-survival mechanisms. We propose that this important flavonoid induces apoptosis in gastric cancer cells by inhibiting Akt activity. Since Akt is often activated in cancers,our findings may have clinical implications. 相似文献
74.
Lingling L Xiaofang Wang Yuancheng Zhu Xinwen Liu Kun Yuan Yongcheng Wang 《科学通报(英文版)》2014,59(3):286-296
The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coupling of triplet state of the minimal energy crossing point(CP)with their singlet states and of the zerofield splitting(ZFS)parameters of the triplet states,including the full one-and two-electron terms of the BreitPauli Hamiltonian.There are two key crossing points along this two-state reaction pathway.The first crossing point—CP2 exists near~1B.The reacting system will change its spin multiplicity from the triplet state to the singlet state near this crossing region.Although the spin-orbit coupling interaction and ZFS D-tensor of the CP2 region are very strong,the reaction system will occur the reverse intersystem crossing from T_1 to S_0.Therefore,its spin-flip efficiency may be lower.The second crossing point,CP3will again change its spin multiplicity from the singlet state to the triplet state in the Co-Cr bond activation pathway,leading to a decrease in the barrier height of~1TS(CF)from19.5 to 9.5 kcal/mol(1cal=4.182 J),and the efficiency of intersystem crossing from S_0 to T_1 is high because the larger spin-orbit coupling(SOC)matrix elements will result in the overpopulations of the three sublevels of T_1(3.30×10~(-1),3.32×10~(-1),and 3.38×10~(-1),respectively). 相似文献
75.
The uniformity of two pairs of color spaces based on CIE 1997 color appearance model (CIECAM97s) is analyzed according to color-discrimination ellipses that are constructed using color-difference evaluation data. A new uniform color space named Jucs a ucs b ucs is deduced by re-scaling the coordinates of lightness, redness-greenness and vellowness-blueness in two initial color spaces using linear regression method. The uniformity of the new color space is obviously improved compared with the initial color spaces. 相似文献
76.
WANG Na WEN XinYu WANG Jie LI AiLing LI WeiHua LI Tao Li Yan ZHANG XueMin WANG HongXia YANG SongCheng ZHOU Tao GONG WeiLi TIAN YaPing & HE Kun National Center of Biomedical Analysis Beijing Chinese People’s Liberation Army General Hospital Beijing 《科学通报(英文版)》2009,54(3):421-429
Early detection of breast cancer is paramount to successful clinical therapy. Yet, early-stage breast cancer lacks specific
symptoms or biomarkers. With the emerging of the mass spectrometric (MS)–based signatures as biomarkers, we investigated breast
cancer-related serum profile pattern through class prediction and independent validation, and used Fourier transfer MS to
identify breast cancer signature. We now show a distinctive serum peptide pattern that discriminates breast cancer from healthy
controls with 93.2% sensitivity and 95.4% specificity. m/z 5901.70 and 4465.74 of ion fragment of FPA and alpha1-antichymotrypsin are found in the signatures that predominantly discriminate
breast cancer from healthy individuals. These novel findings identify an MS-based serum peptide pattern of breast cancer that
may have direct clinical utility in future.
Contributed equally to this work
Supported by National Natural Science Foundation of China (Grant No. 30321003) and National Key Basic Research and Development
Program of China (Grant No. 2004CB518800) 相似文献
77.
提出了一种基于脉冲耦合神经网络(PCNN)的Live wire分割新方法,Live wire方法是把图像当作一个连通图,在边上定义一个代价函数,然后通过搜索最短路径来找物体的边界,把用户指定的物体边界上的两点之间的最短路径当作物体的边界。最短路径是Live wire方法的重要步骤,本文在介绍脉冲耦合神经网络的基本工作原理和特性的基础上,将改进的脉冲耦合神经网络算法引入到Live wire边缘检测的算法中,用于最短路径算法的研究。并在改进算法中应用路径封锁和在线训练来提高算法的准确性和应用性。 相似文献
78.
HE Kun ZHAO Yong 《武汉大学学报:自然科学英文版》2007,12(2):260-266
A new heuristic approach that resembles the evolution of interpersonal relationships in human society is put forward for the problem of scheduling multitasks represented by a directed acyclic graph. The algorithm includes dynamic-group, detachgraph and front-sink components. The priority rules used are new. Relationship number, potentiality, weight and merge degree are defined for cluster's priority, and task potentiality for tasks' priority. Experiments show the algorithm could get good result in short time. The algorithm produces another optimal solution for the classic MJD benchmark. Its average performance is better than five latter-day representative algorithms, especially six benchmarks of the nines. 相似文献
79.
Kun Huang Bang fen Zhu Institute of Semiconductors Chinese Academy of Sciences P. O. Box Beijing China 《清华大学学报》1998,(1)
PolarOpticalVibrationModesinSemiconductorSuperlaticesKunHuang,Bang-fenZhuInstituteofSemiconductors,ChineseAcademyofSciencesP.... 相似文献
80.
Unusual high-density and saline aqueous inclusions in ultrahigh pressure metamorphic rocks from Sulu terrane in eastern China 总被引:1,自引:2,他引:1
SHEN Kun ZHANG Zeming A. M. van den Kerkhof XIAO Yilin XU Zhiqin & J. Hoefs . Institute of Geological Sciences of Shandong Jinan China . Institute of Geology CAGS Beijing China . Geoscience Center University Gttingen Gttingen Germany Correspondence should be addressed to Zhang Zeming 《科学通报(英文版)》2003,48(18):2018-2023
Fluid inclusions are the samples of metamorphic fluids trapped during the formation and/or later fractur-ing-resealing processes of metamorphic minerals. The composition and properties of fluid incluisons can reflect the physico-chemical conditions of the fluids during plate subduction and exhuamtion[1]. Ultrahigh pressure (UHP) metamorphic rocks commonly experienced considerable decompression in the course of exhumation process. This has caused departure of the retrograde P-T path of the ro… 相似文献