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61.
Making use of Microsoft Visual Studio. NET platform, hierarchical network planning is realized in working procedure time-optimization of the construction by TBM. and hierarchical network graph of the construction by TBM is drawn based on browser. Then the theory of system realization is discussed, six components of system that can be reused are explained emphatically. The realization of hierarchical network panning in Internet provides available guarantee for controlling rate of progress in large-scale or middle-sized projects.  相似文献   
62.
Calcineurin (CN) is thought to play a role in the synaptic plastivity and long-term potentiation (LTP) in the hippocampus. Based on two LTP models in vivo, a specific inhibitor cyclosporin A (CsA) of CN was observed, which affected LTP in the hippocampal dentate gyrus of the rats. The results indicated that CsA blocked LTP induced by high frequency stimulation (HFS) partly, but it had no effect on the decrease of the onset and peak latency of population spikes (PS) except that it reduced the increase of the amplitude after HFS. On the other hand, CsA blocked LTP induced by ginsenosides (GSS) completely. It suppressed the GSS-enhanced amplitude of PS reversibly and blocked the decrease of the peak latency of PS induced by the GSS. These results suggest that the postsynaptic CN plays a role in the induction of LTP in the hippocampus of the rats.  相似文献   
63.
MDC1 is coupled to activated CHK2 in mammalian DNA damage response pathways   总被引:19,自引:0,他引:19  
Lou Z  Minter-Dykhouse K  Wu X  Chen J 《Nature》2003,421(6926):957-961
Forkhead-homology-associated (FHA) domains function as protein-protein modules that recognize phosphorylated serine/threonine motifs. Interactions between FHA domains and phosphorylated proteins are thought to have essential roles in the transduction of DNA damage signals; however, it is unclear how FHA-domain-containing proteins participate in mammalian DNA damage responses. Here we report that a FHA-domain-containing protein-mediator of DNA damage checkpoint protein 1 (MDC1; previously known as KIAA0170)--is involved in DNA damage responses. MDC1 localizes to sites of DNA breaks and associates with CHK2 after DNA damage. This association is mediated by the MDC1 FHA domain and the phosphorylated Thr 68 of CHK2. Furthermore, MDC1 is phosphorylated in an ATM/CHK2-dependent manner after DNA damage, suggesting that MDC1 may function in the ATM-CHK2 pathway. Consistent with this hypothesis, suppression of MDC1 expression results in defective S-phase checkpoint and reduced apoptosis in response to DNA damage, which can be restored by the expression of wild-type MDC1 but not MDC1 with a deleted FHA domain. Suppression of MDC1 expression results in decreased p53 stabilization in response to DNA damage. These results suggest that MDC1 is recruited through its FHA domain to the activated CHK2, and has a critical role in CHK2-mediated DNA damage responses.  相似文献   
64.
0 IntroductionTheneedforintegrationofdifferentdatabasemanagementsystems (DBMSs) ,makingdifferencesbetweenthesesystemsinvisibleandprovidinguserswithauniformaccesstoallthedatabaseshasgrownrapidlyduringthelastdecade .However,databaseautonomyandheterogeneity…  相似文献   
65.
The effects and the relationship between sali-cylic acid(SA)and nitric oxide(NO) on Vicia faba L.stomatal movement were studied.The results here showed that exogenous SA and NO induced stomatal closure,100μmol/L SA induced a rapid and striking NO increase in the cytosol of guard cells.This phenomenon was largely prevented by 2000μmol/L 2-phenyl-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide(PTIO),a specific NO scavenger,and 25μmol/L N^G-nitro-L-Arg-methyl eater (L-NAME),an inhibitor of NO synthase(NOS) in mammalian cells that also inhibits plant NOS.In addition,SA-induced stomatal closure was largely prevented by PTIO and L-NAME.These results provide evidence that guard cells generate NO in response to SA via NOS-like activity,and that such NO production is required for full stomatal closure in response to SA.H-(1,2,4)-oxadiazole-[4,3-α]quinoxalin-l-one(ODQ),an inhibitor of guanylate cyclase,and nicotinamide,an antagonist of cADPR production,inhibited the effects of SA-and NO-induced stomatal closure.It suggests that both cGMP and cADPR might mediate the signal transduction of SA and NO-induced stomatal closure.  相似文献   
66.
在铸铁平板像素检测法中,针对图像的不均匀特点,建立了铸铁平板图像的数学模型,并在此基础上提出了以二维插值为基础的铸铁平板图像均匀化方法.结果表明,该方法的均匀化效果良好,均匀化后的平板图像可直接用Otsu方法对其讲行分割.分割效果满足应用要求.  相似文献   
67.
作者根据近年对超限运输桥梁及大中型桥梁的加固实践经验,介绍了公路旧桥各组成部分的加固方法和施工措施。  相似文献   
68.
娄胜霞 《河南科学》2010,28(5):617-622
概括分析了生态足迹和区域发展规划的概念、理论及发展背景,并对其理论的国内外演变历程加以详细论述,尤其是对生态足迹模型理论做了深入的探析.在此基础上,通过分析生态观对经济发展产生的作用、生态观为区域规划带来的影响以及区域规划为生态经济的发展带来的条件,来完成生态观对区域发展规划的方法论研究,以期为制定区域经济及区域可持续发展政策提供理论支持.  相似文献   
69.
探讨戴芬在妇科镇痛领域的应用   总被引:1,自引:0,他引:1  
目的 探讨妇科门诊手术无吕腔操作的方法。方法 204例患者随机分为3组,分别经戴芬(双氯芬酸钠)口服、利多卡因宫颈注射及精神无痛法镇痛,观察术中疼痛程度和不良反应。结果 无痛结果,戴芬>利多卡因>精神无痛法;不良反应,戴芬<利多卡因<精神无痛法。结论 戴芬用于妇科门诊手术痛领域效果好。  相似文献   
70.
Affine ellipses/ellipsoids based bounding volumes are widely used in various graphics applications,such as ray tracing and collision detection.They provide a much tighter fit than the regular ellipses/ellipsoids.The most important operation involved is to compute the closest/farthest point,on a given ellipse/ellipsoid,with respect to a user specified point.In this paper,we first formulate such a problem for the ellipse case into solving a quartic equation and then for the ellipsoid case by solving a system of quartic equations.The method proposed in this paper is elegant and highly efficient.  相似文献   
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