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1.
Due to the fact that the flood data series of small drainage basins is relatively short, available data are often not sufficient for flood risk analysis. This presents the problem of risk analysis using very small data samples. One method that can be applied is to regard the available small samples as fuzzy information and optimize them using information diffusion technology to yield analytical results with greater reliability. In this article a risk analysis method based on information diffusion theory is applied to create a new flood risk analysis model. Application of the model is illustrated taking the Jinhuajiang and Qujiang drainage basins as examples. This is a new attempt at applying information diffusion theory in flood risk analysis. Computations based on this analytical flood risk model can yield an estimated flood damage value that is relatively accurate. This study indicates that the aforementioned model exhibits fairly stable analytical results, even when using a small set of sample data. The results also indicate that information diffusion technology is highly capable of extracting useful information and therefore improves system recognition accuracy. This method can be easily applied and the analytical results produced are easy to understand. Results are accurate enough to act as a guide in disaster situations.  相似文献   
2.
The amino-terminal domain of the large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) contains a serine/threonine-specific protein kinase that has characteristics of a growth factor receptor (Chung, T. D., Wymer, J. P., Smith, C. C., Kulka, M., and Aurelian, L. (1989) J. Virol. 63, 3389-3398; Chung, T. D., Wymer, J. P., Kulka, M. Smith, C. C., and Aurelian, L. (1990) Virology 179, 168-178). To characterize this protein kinase (PK) domain further we constructed a bacterial expression vector (pJL11) containing DNA sequences encoding ICP10 amino acid residues 1-445. Bacteria containing pJL11 were induced to express a 29-kDa protein (designated pp29la1) that represents a truncated portion of the ICP10-PK domain (includes PK catalytic motifs I-V) as demonstrated by immunoprecipitation with antibodies that recognize different antigenic domains, competition studies with extracts of ICP10-positive eukaryotic cells, and peptide mapping.pp29la1 has autophosphorylating and transphosphorylating activity for calmodulin. The enzyme is activated by Mn2+ but not by Mg2+ ions, and autophosphorylation is inhibited by histone. It differs from the authentic ICP10-PK in that phosphorylation is specific only for threonine.  相似文献   
3.
本文研究了中国广东汉族健康人群apoAI-CⅢ-AIV基因簇DNA限制性内切酶PstI、SstI和EcoRI片段长度多态性。其中等位基因P_1,P_2,S_1,S_2,R_1和R_2的频率分别为0.98,0.02,0.96,0.04,0.90和0.10。经卡方检验符合Hardy-Weinbery氏遗传平衡,与其他种族比较,本文结果显示中国广东汉族人P_2等位基因频率低于日本人、亚洲印第安人和高加索人,S_2等位基因频率低于日本人、菲律宾人、沙特阿拉伯人和亚洲印第安人,而与高加索人相近,R_2等位基因频率稍高于高加索人。不同种族间apoAI-CⅢ-AIV基因簇DNA多态频率无疑存在差异,这种差异可能是由于遗传漂变和自然选择单独或联合作用所致。对P_1、P_2,S_1、S_2和R_1、R_2构成的单倍型和连锁平衡程度进行了分析,结果显示这些单倍型处于连锁不平衡状态。  相似文献   
4.
A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometr...  相似文献   
5.
The DNA methyltransferases (DNMTs) were found in mammals to maintain DNA methylation. Among them, DNMT1 was the first identified, and it is an attractive target for tumour chemotherapy. DC_05 and DC_517 have been reported in our previous work, which is non-nucleoside DNMT1 inhibitor with low micromolar IC50 values and significant selectivity towards other S-adenosyl-L-methionine (SAM)-dependent protein methyltransferases. In this study, through a process of similarity-based analog searching, a series of DNMT1 inhibitors were designed, synthesized, and evaluated as anticancer agents. SAR studies were conducted based on enzymatic assays. And most of the compounds showed strong inhibitory activity on human DNMT1, especially WK-23 displayed a good inhibitory effect on human DNMT1 with an IC50 value of 5.0 µM. Importantly, the pharmacokinetic (PK) profile of WK-23 was obtained with quite satisfying oral bioavailability and elimination half-life. Taken together, WK-23 is worth developing as DNMT1-selective therapy for the treatment of malignant tumour.  相似文献   
6.
重庆市爬行动物物种多样性研究及保护   总被引:6,自引:4,他引:6  
罗键  高红英  周元媛 《四川动物》2004,23(3):249-256
1996~2004年对重庆市35个县(区、市)进行野外调查采集,结合有关资料记载,重庆市共有爬行动物2目12科38属58种,其中龟鳖目4种,有鳞目蜥蜴亚目12种、蛇亚目42种(含重庆市蛇类新记录3属4种)。建议加强对该市爬行动物物种多样性及其生境的保护,合理利用爬行动物资源。  相似文献   
7.
Negative control of p53 by Sir2alpha promotes cell survival under stress.   总被引:50,自引:0,他引:50  
J Luo  A Y Nikolaev  S Imai  D Chen  F Su  A Shiloh  L Guarente  W Gu 《Cell》2001,107(2):137-148
The NAD-dependent histone deacetylation of Sir2 connects cellular metabolism with gene silencing as well as aging in yeast. Here, we show that mammalian Sir2alpha physically interacts with p53 and attenuates p53-mediated functions. Nicotinamide (Vitamin B3) inhibits an NAD-dependent p53 deacetylation induced by Sir2alpha, and also enhances the p53 acetylation levels in vivo. Furthermore, Sir2alpha represses p53-dependent apoptosis in response to DNA damage and oxidative stress, whereas expression of a Sir2alpha point mutant increases the sensitivity of cells in the stress response. Thus, our findings implicate a p53 regulatory pathway mediated by mammalian Sir2alpha. These results have significant implications regarding an important role for Sir2alpha in modulating the sensitivity of cells in p53-dependent apoptotic response and the possible effect in cancer therapy.  相似文献   
8.
Li X  Luo X  Li Z  Wang G  Xiao H  Tao D  Gong J  Hu J 《Molecular biology reports》2012,39(8):8225-8230
Salvador promotes both cell cycle exit and apoptosis through the modulation of both cyclin E and Drosophila inhibitor of apoptosis protein in Drosophila. However, the cellular function of human Salvador (hSav1) is rarely reported. To screen for novel binding proteins that interact with hSav1, the cDNA of hSav1 was cloned into a bait protein plasmid, and positive clones were screened from a human fetal liver cDNA library by the yeast two-hybrid system. hSav1 mRNA was expressed in yeast and there was no self-activation and toxicity in the yeast strain AH109. Twenty proteins were found to interact with hSav1, including HS1 (haematopoietic cell specific protein1)-associated protein X-1 (HAX-1); neural precursor cell expressed, developmentally down-regulated 9, pyruvate kinase, liver and RBC, cytochrome c oxidase subunit Vb, enoyl coenzyme A hydratase short chain 1, and NADH dehydrogenase (ubiquinone) 1 beta subcomplex, demonstrating that the yeast two-hybrid system is an efficient method for investigating protein interactions. Among the identified proteins, there were many mitochondrial proteins, indicating that hSav1 may play a role in mitochondrial function. We also confirmed the interaction of HAX-1 and hSav1 in mammalian cells. This investigation provides functional clues for further exploration of potential apoptosis-related proteins in disease biotherapy.  相似文献   
9.
The function of NS4B is incompletely understood. The aim of the study is to understand the influence of NS4B on anti-viral response. After cell line stably expressing NS4B established, the influence of IFN-alpha of different concentration on VSV was studied using plaque assay; cell expression profiling caused by NS4B was studied using DNA microarray, and the IFNGR1 fluorescence intensity was analyzed. Our data showed that HCV-NS4B could suppress immuno-associated gene expression, in particular, IFN-gamma receptor signal transduction-related genes. Taken together, NS4B could play some roles in HCV resistance to IFN therapy.  相似文献   
10.
Hu ZA  Tan YL  Luo J  Li HD  Li XC  Yu ZP 《生理学报》2004,56(1):89-94
既往研究发现,神经细胞粘附分子(neural cell adhesion molecules,NCAM)对海马CA1区突触传递长时程增强(longterm potentiation,LTP)的诱导和维持极为关键。本文采用原位杂交法和Western blot法,观察了大鼠海马腑片LTP诱导和维持过程中NCAM mRNA和蛋白水平的动态变化过程。结果显示,强直刺激诱发fEPSP斜率升高10 min时,海马CA1区NCAM mRNA染色阳性神经元数量显著增加(76.6±11.5个),NCAM蛋白水平亦明显升高(7.190±0.64任意单位/50μg蛋白)。强直刺激诱发fEPSP斜率升高1 h时,NCAM mRNA染色阳性神经元数量为73.3±14.0个,NCAM蛋白量为9.031±0.71任意单位/50 μg蛋白;与强直刺激后10 min比较,NCAM mRNA表达无显著变化,而NCAM蛋白水平变化明显。NMDA受体特异阻断剂AP-5在损害LTP的同时,显著抑制NCAM mRNA和蛋白的增加。实验结果表明,在大鼠海马LTP诱导和维持过程中,NCAM mRNA增强的表达相对稳定,而NCAM蛋白水平呈现先低后高的变化。  相似文献   
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