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排序方式: 共有144条查询结果,搜索用时 31 毫秒
1.
Panos M. Pardalos Wanpracha Chaovalitwongse Leonidas D. Iasemidis J. Chris Sackellares Deng-Shan Shiau Paul R. Carney Oleg A. Prokopyev Vitaliy A. Yatsenko 《Mathematical Programming》2004,101(2):365-385
There is growing evidence that temporal lobe seizures are preceded by a preictal transition, characterized by a gradual dynamical change from asymptomatic interictal state to seizure. We herein report the first prospective analysis of the online automated algorithm for detecting the preictal transition in ongoing EEG signals. Such, the algorithm constitutes a seizure warning system. The algorithm estimates STLmax, a measure of the order or disorder of the signal, of EEG signals recorded from individual electrode sites. The optimization techniques were employed to select critical brain electrode sites that exhibit the preictal transition for the warning of epileptic seizures. Specifically, a quadratically constrained quadratic 0-1 programming problem is formulated to identify critical electrode sites. The automated seizure warning algorithm was tested in continuous, long-term EEG recordings obtained from 5 patients with temporal lobe epilepsy. For individual patient, we use the first half of seizures to train the parameter settings, which is evaluated by ROC (Receiver Operating Characteristic) curve analysis. With the best parameter setting, the algorithm applied to all cases predicted an average of 91.7% of seizures with an average false prediction rate of 0.196 per hour. These results indicate that it may be possible to develop automated seizure warning devices for diagnostic and therapeutic purposes.Mathematics Subject Classification (1991):20E28, 20G40, 20C20 相似文献
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A periodic one-dimensional four-state hopping model is proposed. In the model, the substeps betweenarbitrary adjacent states are unequal, and an explicit solution of the master equation is first obtained for the probabilitydistribution as a function of the time and position for any initial distribution with all the transients included. Next, thetransient behaviors in the initial period of time and the characteristic time to reach the steady state for the molecularmotor are discussed. Finally, we compare the steady state results to experiments and illustrate qualitatively the kineticbehaviors of a molecular motor under external load F. 相似文献
3.
David Kessel Kevin M. Smith R. K. Pandey F.-Y. Shiau Barbara Henderson 《Photochemistry and photobiology》1993,58(2):200-203
Abstract— Biophysical and photobiological properties of a group of bacteriochlorins were compared with efficacy of these products for photodynamic therapy of murine tumors. Predictive factors for selective photosensitization in vivo include affinity binding to lipoproteins greater than albumin, extinction coefficient at the wavelength of irradiation and tumor/skin distribution. Efficacy was correlated with circulating plasma levels of the different sensitizers but not with the photodynamic therapy response in cell culture. 相似文献
4.
The preparation of bisaryl carbodiazone compounds from the aryl substituted carbazides with Ceric Ammonium Nitrate (CAN) has been reported for the first time in excellent yields (80-91%). This method only needs simple instruments and short reaction time. A possible mechanism has been suggested. 相似文献
5.
Reconstitution of Nucleosome Demethylation and Catalytic Properties of a Jumonji Histone Demethylase
Carrie Shiau Michael J. Trnka Alen Bozicevic Idelisse Ortiz Torres Bassem Al-Sady Alma L. Burlingame Geeta J. Narlikar Danica Galonić Fujimori 《Chemistry & biology》2013,20(4):494-499
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6.
Sheng-Chieh Wang Meng-Yang Chang Jun-Ping Shiau Ammad Ahmad Farooqi Yu-Hsiang Huang Jen-Yang Tang Hsueh-Wei Chang 《Molecules (Basel, Switzerland)》2022,27(5)
The benzo-fused dioxabicyclo[3.3.1]nonane core is the central framework in several natural products. Using this core, we had developed a novel nitrated [6,6,6]tricycle-derived compound containing an n-butyloxy group, namely, SK2. The anticancer potential of SK2 was not assessed. This study aimed to determine the antiproliferative function and investigated possible mechanisms of SK2 acting on oral cancer cells. SK2 preferentially killed oral cancer cells but caused no harmful effect on non-malignant oral cells. After the SK2 exposure of oral cancer cells, cells in the sub-G1 phase accumulated. This apoptosis-like outcome of SK2 treatment was validated to be apoptosis via observing an increasing annexin V population. Mechanistically, apoptosis signalers such as pancaspase, caspases 8, caspase 9, and caspase 3 were activated by SK2 in oral cancer cells. SK2 induced oxidative-stress-associated changes. Furthermore, SK2 caused DNA damage (γH2AX and 8-hydroxy-2′-deoxyguanosine). In conclusion, a novel nitrated [6,6,6]tricycle-derived compound, SK2, exhibits a preferential antiproliferative effect on oral cancer cells, accompanied by apoptosis, oxidative stress, and DNA damage. 相似文献
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嫁接型席夫碱配合物的制备及其催化性能 总被引:1,自引:0,他引:1
应用超声波技术在温和条件下以氯丙基三甲氧基硅烷为偶联剂, 制得了嫁接过渡金属Zn, Cu, Fe和Co的N,N-双水杨醛缩二乙烯三胺席夫碱配合物[SiO2-M(NNOO)], 并与传统加热搅拌法制得的样品的物性和催化性能做了比较. 应用IR和UV-Vis谱学技术对其进行了初步表征, 结果表明, 两种方法制得的嫁接型配合物的红外光谱均呈现出胺基和席夫碱相应基团的特征吸收, 配体和配合物红外和紫外光谱之间的差别表明配合物结构的存在. 将所制得的样品在苯乙烯选择氧化制苯甲醛反应中进行了催化性能的测试, 考察了反应时间和催化剂对苯乙烯转化率和选择性的影响, 结果表明苯乙烯转化率均在90%以上, 苯甲醛选择性最高可达93.5%, 产物选择性与反应时间和催化剂中过渡金属的类型均有关系. 相似文献