• 제목/요약/키워드: Ping

검색결과 1,340건 처리시간 0.025초

Effects of Celecoxib on Cycle Kinetics of Gastric Cancer Cells and Protein Expression of Cytochrome C and Caspase-9

  • Wang, Yu-Jie;Niu, Xiao-Ping;Yang, Li;Han, Zhen;Ma, Ying-Jie
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2343-2347
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    • 2013
  • Objective: This investigation aimed to determine effects of celecoxib on the cell cycle kinetics of the gastric cancer cell line MGC803 and the mechanisms involved by assessing expression of cytochrome C and caspase-9 at the protein level. Methods: Cell proliferation of MGC803 was determined by MTT assay after treatment with celecoxib. Apoptosis was assessed using fluorescence staining and cell cycle kinetics by flow cytometry. Western blotting was used to detect the expression of caspase-9 protein and of cytochrome C protein in cell cytosol and mitochondria. Results: Celecoxib was able to restrain proliferation and induce apoptosis in a dose- and time-dependent manner, inducing G0/G1 cell cycle arrest, release of cytochrome C into the cytosol, and cleavage of pro-caspase-9 into its active form. Conclusion: Celecoxib can induce apoptosis in MGC803 cells through a mechanism involving cell cycle arrest, mitochondrial cytochrome C release and caspase activation.

Inhibitory Effect of Benzyl Isothiocyanate on Proliferation in vitro of Human Glioma Cells

  • Zhu, Yu;Zhuang, Jun-Xue;Wang, Qin;Zhang, Hai-Yan;Yang, Ping
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2607-2610
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    • 2013
  • Malignant glioma, also known as brain cancer, is the most common intracranial tumor, having an extremely high mortality and recurrence rate. The survival rate of the affected patients is very low and treatment is difficult. Hence, growth inhibition of glioma has become a hot topic in the study of brain cancer treatment. Among the various isothiocyanate compounds, it has been confirmed that benzyl isothiocyanate (BITC) can inhibit the growth of a variety of tumors, including leukemia, glioma and lung cancer, both inside and outside the body. This study explored inhibitory effects of BITC on human glioma U87MG cells, as well as potential mechanisms. It was found that BITC could inhibit proliferation, induce apoptosis and arrest cell cycling of U87MG cells. In addition, it inhibited the expression of SOD and GSH, and caused oxidative stress to tumor cells. Therefore, it is believed that BITC can inhibit the growth of U87MG cells outside the body. Its mechanism may be related to the fact that BITC can cause oxidative stress to tumor cells.

Detection of LSB Matching Revisited Using Pixel Difference Feature

  • Li, Wenxiang;Zhang, Tao;Zhu, Zhenhao;Zhang, Yan;Ping, Xin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권10호
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    • pp.2514-2526
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    • 2013
  • This paper presents a detection method for least significant bit matching revisited (LSBMR) steganography. Previous research shows that the adjacent pixels of natural images are highly correlated and the value 0 appears most frequently in pixel difference. Considering that the message embedding process of LSBMR steganography has a weighted-smoothing effect on the distribution of pixel difference, the frequency of the occurrence of value 0 in pixel difference changes most significantly whereas other values approximately remain unchanged during message embedding. By analyzing the effect of LSBMR steganography on pixel difference distribution, an equation is deduced to estimate the frequency of difference value 0 using the frequencies of difference values 1 and 2. The sum of the ratio of the estimated value to the actual value as well as the ratio of the frequency of difference value 1 to difference value 0 is used as the steganalytic detector. Experimental results show that the proposed method can effectively detect LSBMR steganography and can outperform previous proposed methods.

A Study of the Efficiency of Futures Research Institutes of China

  • WU, Guo-Hua;YAO, Tian-Yin;ZHANG, Bao-Ping
    • The Journal of Asian Finance, Economics and Business
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    • 제7권12호
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    • pp.555-564
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    • 2020
  • The purpose of this study is to analyze the efficiency of research institutes of futures companies, and to promote the development of futures market and real economy. This study employs DEA-solver software to conduct super-efficiency data envelopment analysis (SE-DEA), and also selects 40 representative futures research institutes in China as decision-making units (DMUs). For data of input and output indicators, we collect from the China Futures Association, Futures Daily, Hexun.com and Webstock.com respectively, and the time duration is the 103 trading days between from October 2019 to February 2020. Then the indicator for the strategy accuracy rate is calculated separately by analyzing the strategies published by each DMUs in public media. In conclusions, most institutes have excessive investment in human resources, and also have insufficient strategy accuracy rate and insufficient published research reports. The findings of this study suggest that Chinese futures companies need to improve the efficiency of research institutes, and better meet the demand of the financial market. In fact, the analysis of the efficiency of the futures company research institute has not been found in the literature worldwide, Application of DEA model in efficiency analysis of securities and futures research institutions and establishment of indicators are the innovations of this paper.

Study on the Solid Phase Extraction of Hg(II)-SBDTR Chelate with C18 Disks and Its Application to the Determination of Mercury in Tobacco and Tobacco Additive

  • Yang, Guan-Gyu;Xia, Zhen-Yuang;Wu, Yu-Ping;Sun, Han-Dong;Yin, Jia-Yuan
    • Bulletin of the Korean Chemical Society
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    • 제25권4호
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    • pp.549-552
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    • 2004
  • A sensitive, selective and rapid method has been developed for the determination of mercury based on the rapid reaction of mercury(II) with p-sulfobenzylidenethiorhodanine (SBDTR) and the solid phase extraction of the colored chelate with $C_{18}$ disks. In the presence of pH 3.5 sodium acetate-acetic acid buffer solution and Emulsifier-OP medium, SBDTR reacts with mercury(II) to form a red chelate of a molar ratio 1 : 2 (mercury to SBDTR). This chelate was prconcentrated by solid phase extraction with $C_{18}$ disks. An enrichment factor of 50 was achieved. The molar absorptivity of the chelate is $1.28{\times}10^5 L{\cdot}mol^{-1}{\cdot}cm^{-1}$ at 545 nm in measured solution. Beer's law is obeyed in the range of 0.01-3 ${\mu}$g/mL. The relative standard deviation for eleven replicates sample of 0.01 ${\mu}$g/mL is 1.65%. This method was applied to the determination of mercury in tobacco and tobacco additive with good results.

Unusual Non-magnetic Metallic State in Narrow Silicon Carbon Nanoribbons by Electron or Hole Doping

  • Lou, Ping;Lee, Jin-Yong
    • Bulletin of the Korean Chemical Society
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    • 제33권3호
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    • pp.763-769
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    • 2012
  • We investigated the width (N) dependence on the magnetization of N-ZSiC NR with electron and hole doping on the basis of systematic DFT calculations. The critical values of the upper and down critical concentration to give the maximum and zero magnetic moment at edge Si/C atoms by electron/hole doping ($x_{up,e}$, $x_{down,e}$, $x_{up,h}$, and $x_{down,h}$) depend on the width of N-ZSiC NR. Moreover, due to $x_{up,e}\;{\neq}\;x_{up,h}$ and $x_{down,e}\;{\neq}\;x_{down,h}$, the electron and hole doping effect are asymmetry, i.e, the critical electron doping value ($x_{down,e}$) is smaller than the critical hole doping value ($x_{down,h}$) and is almost independent of the width of NZSiC NR though the other critical values of the electron and hole doping that influence the magnetization of N-ZSiC NR depend on the width. It was also found that at $x_{down,e}$ or $x_{down,h}$ doping, the N-ZSiC NR turns into unusual non-magnetic metallic state. The magnetic behavior was discussed based on the band structures and projected density of states (PDOS) under the effect of electron/hole doping.

Cyanide- and Phenoxo-Bridged Heterobimetallic Fe(III)-Mn(III) Coordination Polymer: Synthesis, Crystal Structures and Magnetic Properties

  • Zhang, Daopeng;Kong, Lingqian;Li, Yueyun;Wang, Ping;Chen, Xia
    • Bulletin of the Korean Chemical Society
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    • 제35권9호
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    • pp.2684-2688
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    • 2014
  • Two two-dimensional cyanide- and phenoxo-bridged heterometallic M(II)-Mn(III) (M = Ni, Pd) coordination polymers $\{[Mn(saltmen)]_4[Ni(CN)_4]\}(ClO_4)_2{\cdot}CH_3OH{\cdot}H_2O$ (1) and $\{[Mn(saltmen)]_4[Pd(CN)_4]\}(ClO_4)_2{\cdot}CH_3CN{\cdot}H_2O$ (2) ($saltmen^{2-}$ = N,N'-(1,1,2,2-tetramethylethylene)bis(salicylideneaminato)dianion) have been obtained by using $K_2[M(CN)_4]$ as building blocks and a salen-tpye Schiff-base manganese(III) compound as assembling segment. Single X-ray analysis reveals their isostrutural cyanide-bridged $MMn_4$ pentanuclear cationic structure. The four Schiff base manganese units of the pentanuclear entity are self-complementary through the phenoxo oxygen atoms from the neighboring complex, therefore forming cyanide- and phenoxo-bridged 2D sheet-like structure. Investigation over magnetic susceptibilities reveals the overall ferromagnetic coupling between the adjacent Mn(III) ions bridged by the phenoxo oxygen atoms with J = 2.13 and $2.21cm^{-1}$ for complexes 1 and 2, respectively.

Theoretical Study on the Reaction Mechanism of Azacyclopropenylidene with Epoxypropane: An Insertion Process

  • Tan, Xiaojun;Wang, Weihua;Li, Ping
    • Bulletin of the Korean Chemical Society
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    • 제35권9호
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    • pp.2717-2722
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    • 2014
  • The reaction mechanism between azacyclopropenylidene and epoxypropane has been systematically investigated employing the second-order M${\o}$ller-Plesset perturbation theory (MP2) method to better understand the reactivity of azacyclopropenylidene with four-membered ring compound epoxypropane. Geometry optimization, vibrational analysis, and energy property for the involved stationary points on the potential energy surface have been calculated. It was found that for the first step of this reaction, azacyclopropenylidene can insert into epoxypropane at its C-O or C-C bond to form spiro intermediate IM. It is easier for the azacyclopropenylidene to insert into the C-O bond than the C-C bond. Through the ring-opened step at the C-C bond of azacyclopropenylidene fragment, IM can transfer to product P1, which is named as pathway (1). On the other hand, through the H-transferred step and subsequent ring-opened step at the C-N bond of azacyclopropenylidene fragment, IM can convert to product P2, which is named as pathway (2). From the thermodynamics viewpoint, the P2 characterized by an allene is the dominating product. From the kinetic viewpoint, the pathway (1) of formation to P1 is primary.

Hepatic Angiomyolipoma: Contrast Patterns with SonoVue-enhanced Real-time Gray-scale Ultrasonography

  • Wei, Rui-Xue;Wang, Wen-Ping;Ding, Hong;Huang, Bei-Jian;Li, Chao-Lun;Fan, Pei-Li;Hou, Jun;He, Nian-An
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권2호
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    • pp.493-497
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    • 2012
  • This study was conducted to retrospectively evaluate the pattern of contrast enhancement with SonoVue on gray-scale ultrasonography of hepatic angiomyolipoma (HAML). Imaging features of 33 pathologically proven HAML lesions in 33 patients who underwent baseline ultrasound and contrast-enhanced ultrasonography (CEUS) were assessed retrospectively. All lesions were enhanced in the arterial phase and showed whole-tumor filling in. Thirty-two of 33 (97%) lesions showed early positive enhancement in the arterial phase. Twenty-three of these exhibited isoechoic or hyperechoic features in the portal phase. HAML demonstrate characteristic manifestations with SonoVue-enhanced real-time gray-scale ultrasonography.

Glutathione-S-Transferase T1 Polymorphism is Associated with Esophageal Cancer Risk in Chinese Han Population

  • Weng, Yuan;Fei, Bojian;He, Ping;Cai, Ming
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권9호
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    • pp.4403-4407
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    • 2012
  • Background: Glutathione-S-Transferase T1 (GSTT1) gene has been shown to be involved in the development of esophageal cancer. However, the results have been inconsistent. In this study, the authors performed a meta-analysis to clarify the association between GSTT1 polymorphism and esophageal cancer risk among Chinese Han population. Methods: Published literature from PubMed, the China National Knowledge Infrastructure and Wanfang Data were searched. Pooled odds ratio (OR) and 95% confidence interval (95%CI) was calculated using a fixed- or random-effects model. Results: Eleven studies with a total of 2779 individuals were included in the meta-analysis. The results showed that GSTT1 null genotype was significantly associated with esophageal cancer risk in Chinese (OR = 1.31, 95%CI 1.12 to 1.53, p = 0.001). Further sensitivity analyses confirmed the significant association. The cumulative meta-analysis showed a trend of an obvious association between GSTT1 null genotype and esophageal cancer risk as information accumulated by year. Conclusions: This meta-analysis suggests a significant association of GSTT1 null genotype with esophageal cancer risk in the Chinese Han population.