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991.
992.
Ming‐Jang Chiu Ching‐Wei Lin Chih‐Chuan Chen Ta‐Fu Chen Ya‐Fang Chen Hon‐Man Liu Chih‐Pang Chu Horng‐Huei Liou Mau‐Sun Hua 《Epilepsia》2010,51(6):1036-1042
Purpose: Temporal lobe epilepsy (TLE) is the most common focal epilepsy and frequently causes memory problems. It is often associated with hippocampal sclerosis (HS) and is useful in exploring memory functions. We aimed to examine the effect of restricted hippocampal lesions on gist memory function in patients with TLE. Methods: Forty‐five patients with TLE and HS (16 left, 15 right, and 14 bilateral lesions) and 22 control subjects were recruited. Patients with magnetic resonance imaging (MRI) or electroencephalography (EEG) evidence of extratemporal lesions were excluded. All participants performed a gist‐based recognition task following the Deese‐Roediger‐McDermott paradigm and were tested for verbal IQ and memory functions. We conducted hippocampal volumetry on MRI of all the participants. Results: Patients showed multidomain memory impairments. Gist memory was impaired in patients with bilateral HS and probably in patients with right HS. Hippocampal volumetry supported such findings that total volume of hippocampi and volume of right hippocampus correlated positively with gist memory function. Discussion: HS has a dose effect and a probable right dominance effect on gist memory; good item memory supports gist memory performance; and a disproportionate deficit was noted in tasks with high relational demand but not in tasks with simple association. We should develop memory skills for patients with TLE by enhancing performance of gist memory related to simple association task. 相似文献
993.
994.
Chiu‐Chun Lin Mei‐Chi Chang Hsiao‐Hua Chang Tong‐Mei Wang Wan‐Yu Tseng Tseng‐Fang Tai Hung‐Wei Yeh Ting‐Ting Yang Liang‐Jiunn Hahn Jiiang‐Huei Jeng 《Environmental and molecular mutagenesis》2009,50(5):367-374
Epidemiological studies have shown a strong association between environmental exposure to betel quid (BQ) and oral cancer. Areca nut (AN), an ingredient of BQ, contains genotoxic and mutagenic compounds. In this study, we found that AN extract (ANE) inhibited the growth of Chinese hamster ovary cells (CHO‐K1) in a dose‐ and time‐dependent manner. Intracellular reactive oxygen species (ROS) levels and micronuclei (MN) frequency were significantly increased following ANE treatment in CHO‐K1 cells. Addition of catalase markedly inhibited ANE‐induced MN formation, indicating that ANE‐induced genotoxicity was correlated with intracellular H2O2. Incubation of CHO‐K1 cells with ANE (400–800 μg/ml) for 24 hr caused G2/M arrest, and prolonged exposure to ANE (800 μg/ml) significantly induced cell death. Surprisingly, ANE itself caused cytokinesis failure and subsequent increase in binucleated cell formation. Coexposure to catalase (2,000 U/ml) and ANE (800 μg/ml) reduced the generation of binucleated cells, indicating that ANE‐induced cytokinesis failure was associated with oxidative stress. Following prolonged exposure to ANE, an accumulation of hyperploid/aneuploid cells concomitant with bi‐, micro‐ or multinucleated cells was found. In summary, our results demonstrate that ANE exposure to CHO‐K1 cells caused increased MN frequency, G2/M arrest, cytokinesis failure, and an accumulation of hyperploid/aneuploid cells. These events are associated with an increase in intracellular H2O2 level and actin filament disorganization. Environ. Mol. Mutagen., 2009. © 2009 Wiley‐Liss, Inc. 相似文献
995.
996.
新型乙酰胆碱酯酶抑制剂5H-噻唑并[3,2-a]嘧啶类化合物的设计、合成与生物活性研究 总被引:1,自引:0,他引:1
目的 寻找作为乙酰胆碱酯酶抑制剂的具有新化学结构类型的化合物。方法 采用分子对接的虚拟筛选方法寻找新型乙酰胆碱酯酶抑制剂,设计了10个5H-噻唑并[3,2-a]嘧啶类化合物。以芳醛、硫脲等为起始原料,通过Biginelli反应生成二氢嘧啶类化合物,再与氯代苯乙酮作用经Hantzsch环合反应制得目标化合物,其结构经红外光谱、质谱、核磁共振氢谱和碳谱确证。采用Ellman方法进行体外抑制乙酰胆碱酯酶活性测试。 结果 合成了10个5H-噻唑并[3,2-a]嘧啶类化合物,体外抑制乙酰胆碱酯酶活性测试结果显示,所有目标化合物均具有乙酰胆碱酯酶抑制活性,其中3个目标化合物在10 μmol.L-1时抑制活性均超过50%。结论5H-噻唑并[3,2-a]嘧啶类化合物是潜在的乙酰胆碱酯酶抑制剂。将计算机辅助药物分子设计、有机合成和生物活性测试相结合是发现和设计新型乙酰胆碱酯酶抑制剂的有效途径。 相似文献
997.
998.
Ming-Ni Lee Ruo-Chia Tseng Han-Shui Hsu Jia-Yang Chen Ching Tzao William L Ho Yi-Ching Wang 《Clinical cancer research》2007,13(3):832-838
PURPOSE: Lung cancer cells frequently exhibit marked chromosome instability. We postulated that alterations of the double-strand break repair genes (BRCA1, BRCA2, and XRCC5) might be involved in lung cancer. PATIENTS AND METHODS: We examined the loss of protein and mRNA expression and the 5'CpG hypermethylation and allelic imbalance of the BRCA1, BRCA2, and XRCC5 genes in 98 non-small cell lung cancer (NSCLC) samples. Anchorage-dependent growth after reexpression of these genes was examined in a lung cancer cell line that originally lacked BRCA1 and BRCA2 expression. RESULTS: The data indicated that low protein expression of BRCA1 and BRCA2 was frequent in lung adenocarcinomas (42-44%), whereas low XRCC5 protein expression was more prevalent among squamous cell carcinoma (32%). In addition, low BRCA1 expression was significantly associated with low RB expression, especially in lung adenocarcinoma. Concurrent alterations in XRCC5 and p53 were the most frequent profiles in smoking patients. Importantly, low mRNA and protein expressions of BRCA1, BRCA2, and XRCC5 were significantly associated with their promoter hypermethylation. 5-Aza-2'-deoxycytidine treatment of NSCLC cells showed demethylation and reexpression of the BRCA1 and BRCA2 genes and reduced anchorage-independent growth. CONCLUSIONS: Our retrospective study provides compelling evidence that low mRNA and protein expression in the BRCA1/BRCA2 and XRCC5 genes occur in lung adenocarcinoma and squamous cell carcinoma, respectively, and that promoter hypermethylation is the predominant mechanism in deregulation of these genes. Alteration of the double-strand break repair pathway, perhaps by interacting with p53 and RB deregulation, is important in the pathogenesis of a subset of NSCLC. 相似文献
999.
1000.
目的:采用高效液相色谱法测定脑络通胶囊中维生素B6的含量。方法:以十八烷基硅烷键合硅胶为填充剂,以0.5%磷酸二氢钾.甲醇.三乙胺(85:14.5:0.5)为流动相,流速1.0mL·min^-1,检测波长290nm。结果:进样量在0.646—2.582μg范围内与峰面积呈良好的线性关系,相关系数0.9999,回收率100.16%。结论:本方法操作简便,精密度好,结果准确可靠,可以作为该药品的质量检测标准。 相似文献