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41.
CHEN Jie DONG Xin-shu GUO Xing-gang The Affiliated Tumor Hospital Harbin Medical University Harbin P. R. China 《高等学校化学研究》2008,24(6)
To explore the functional mechanism of Resveratrol against colon cancer cells Is174t and the growth of colon cancer tissue of tumor-bearing mice,MTT method was used to observe the functions of resveratrol for inhibition against cells ls174t in vitro.Transmission electron microscope was used to observe the cell apoptosis.FCM assay was performed to measure the change of the cell apoptosis rate and of cell cycle,RT-PCR method was used to detect the expressions of bc1-2 and bax mRNA.Western blot method was used to detect the expressions of bc1-2 and bax protein.Cells isi74t were transplanted subcutaneously to nude mice to observe the effect of resveratrol on the growth of subcutaneously transplanted tumor.RT-PCR method was used to detect the expressions of bc1-2 and bax mRNA in the tumor tissue.Western blot method was used to detect the expressions of bc1-2 and bax protein in the tumor tissue.Resveratrol has an effect of inhibiting proliferation of cells ls174t in vitro(P<0.01).It is able to induce the apoptosis of cells Is174t,causing the decrease in the expression of bc1-2 and the increase in the expression of bax.Resveratrol could inhibit the growth of subcutaneously transplanted tumor of nude mice(P<0.05),causing the decrease in the expression of bc1-2 and the increase in the expression of bax.Resveratrol can inhibit the growth of cells 174t and the growth of subcutaneously transplanted tumor.The mechanism is possibly related to the induction of the cell apoptosis and the regulation of bc1-2/bax expression. 相似文献
42.
采用蒙特卡罗方法,对EACVD中氢原子的发射过程进行了模拟。给出了由氢原子谱线测定电子平均能量的方法,结果对EACVD生长金刚石薄膜过程中实时监测电子平均能量,进而可以有效地控制工艺条件,生长出高质量的金刚石薄膜具有重要意义。 相似文献
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44.
通过对40例疤痕组织和正常皮肤组织的ETIR光谱比较分析发现,由于个体差异,其光谱均可分为三种不同类型。此外,疤痕组织中的胶原、蛋白质、核酸和脂类等生物大分子的吸收峰强度均在不同程度上高于正常皮肤组织,但两者的A_(1083)/A_(1548)并无明显差异。提示疤痕组织中的细胞仍属正常生长,治疗中不应损伤。 相似文献
45.
利用G98及GAMESS从头计算程序的RHF/6-31方法,对β-榄香烯的全部振动基频作了计算,并与实测红外光谱做了对比,归属了它们的振动模式,讨论了它们的特征基频,并对理论计算的振动频率进行了标度校正。 相似文献
46.
WU GuoXiong State Key Laboratory of Ocean Engineering College of Naval Architecture Ocean Civil Engineering Shanghai Jiao Tong University Shanghai China 《中国科学:物理学 力学 天文学(英文版)》2011,(1)
The sloshing of inviscid liquid of stratified density in a rectangular tank is analyzed.As the flow is no longer irrotional,the governing equation is found to be quite different from the Laplace equation used for the liquid of constant density.In particular it contains terms of mixed temporal and spatial derivatives.The problem is solved based on the variable separation method and Laplace transform for the constant Vaisala-Brunt frequency.It is found that the stratification of density may have small effects... 相似文献
47.
ZHAO JinYu LI JiaHuang ZHANG Zheng ZHANG ShuYi QU Min FANG JianWen HUA ZiChun 《中国科学:物理学 力学 天文学(英文版)》2013,(7):1301-1309
The enthalpy and conformational volume changes in the photolyses of carboxy-hemoglobin (HbCO) of human, bovine, pig, horse and rabbit are investigated by photoacoustic calorimetry. Considering the time scales of the exciting laser pulse and the receiving ultrasound transducers (PVDF films and PZT ceramics), as well as the reaction lifetimes in the photolysis processes of HbCO, the measured results are related to the geminate recombination and tertiary relaxation in photolyses of HbCO. Moreover, the quantum yields of the five mammals are also measured by laser pump-probe technique. The results show that the dynamic parameters, such as enthalpy and conformational volume changes, differ between the processes of the geminate recombination and tertiary relaxation. Also, the dynamic parameters differ among the five mammals although some of them may be consistent with each other. 相似文献
48.
A novel reaction of trimethylsilylated arylacetylenes with sulfonyl chlorides was performed in the presence of silver nitrate or triflate.Conjugated vinyl sulfones as dramatic products were obtained in moderate yields and with Z-selectivity.A free radical mechanism has been proposed to account for the formation of the products. 相似文献
49.
FAN QiuBo College of Mathematics Physics Xuzhou Institute of Technology Xuzhou China 《中国科学:物理学 力学 天文学(英文版)》2011,(3)
We demonstrate that an arbitrary Bell state can be achieved in a two qubit anisotropic Heisenberg XY chain via Lyapunov control. During the whole process, we only need to apply an external field along a given direction to a single qubit. This control strategy is effective for all initial states in the four-dimensional Hilbert space where the target state is asymptotically stable. The effects of imperfections on the fidelity for the target state such as Gaussian leakage of local control and localized dephasi... 相似文献
50.
XU ShangJin WU ZhengFei & DENG YunPing College of Mathematics Information Science Guangxi University Nanning 《中国科学A辑(英文版)》2009,(2)
A graph is said to be s-arc-regular if its full automorphism group acts regularly on the set of its s-arcs. In this paper, we investigate connected cubic s-arc-regular Cayley graphs of finite nonabelian simple groups. Two suffcient and necessary conditions for such graphs to be 1- or 2-arc-regular are given and based on the conditions, several infinite families of 1-or 2-arc-regular cubic Cayley graphs of alternating groups are constructed. 相似文献