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991.
992.
Nhiem NX Kim KC Kim AD Hyun JW Kang HK Van Kiem P Van Minh C Thu VK Tai BH Kim JA Kim YH 《Journal of Asian natural products research》2011,13(1):56-61
By various chromatographic methods, one new phenylpropanoid, acanthopanic acid (1), and three known compounds, 1,2-O-dicaffeoylcyclopenta-3-ol (2), (4S)-α-terpineol 8-O-β-D-glucopyranoside (3), and rutin (4), were isolated from the methanol extract of the Acanthopanax koreanum leaves. Their structures were elucidated on the basis of spectroscopic analyses, and their antioxidant activities were evaluated by the intracellular reactive oxygen species (ROS) radical scavenging 2',7'-dichlorofluorescein diacetate assay. Among them, compounds 1, 2, and 4 showed significant scavenging capacity with IC(50) values of 3.8, 2.6, and 2.9?μM, respectively, and compound 3 showed weak scavenging capacity with the inhibition rate of 37% at 40?μM. 相似文献
993.
Zhang L Chen G Wu HH Lu X Pei YH Wu X Pan B Hua HM Bai J 《Journal of Asian natural products research》2011,13(3):225-229
Two new compounds, N-[4'-hydroxy-(E)-cinnamoyl]-l-tyrosine methyl ester (1) and methyl 4-methoxy-3-(3'-hydroxy-2'-methyl)propionyloxy-benzoate (2), were isolated from EtOAc extract of the fermentation broth of the endophytic fungus Aspergillus sp. HS-05. Their structures were elucidated by NMR, IR, UV, MS, and CD methods. Compounds 1 and 2 showed no anticancer activities against HL-60 cell lines (both of IC(50)>100 μM) in vitro. 相似文献
994.
Hong H Chen HB Yang DH Shang MY Wang X Cai SQ Mikage M 《Journal of natural medicines》2011,65(3-4):623-628
In the present paper, a fast and economical HPLC method [on a Phenomenex Polar-RP column with a solution of (phosphoric acid:triethylamine:dibutylamine:water = 0.40:0.1:0.2:499.3) and methanol] is developed, and applied for the determination of norephedrine, norpseudoephedrine, ephedrine (E), pseudoephedrine (PE) and methylephedrine (ME) in 64 samples of three species from main habitats in China. Quantitation data showed that total alkaloid content in Ephedra equisetina Bge. (2.708 ± 0.642%) is higher than that in E. sinica Stapf. (1.365 ± 0.624%) and E. intermedia Schrenk et C. A. Mey. (1.537 ± 0.746%), but the range of total alkaloid content in each species is so wide that the ranges of the three species greatly overlap. The contents of E, PE and ME are different among the three species. The ratio E/total alkaloid content and ratio E/PE as well as E and ME contents can be used for identification of E. sinica, E. intermedia and E. equisetina from one another. 相似文献
995.
996.
目的:观察非小细胞肺癌行三维适形低分割高剂量放射治疗的疗效与并发症,探讨适合的分割模式和照射剂量。方法:回顾性分析682例非小细胞肺癌,采用三维适形放射治疗,90%-95%的剂量曲线覆盖PTV,单次分割剂量5Gy,1次/日或隔日,3-5次/周,DT50-70Gy/10-14次,中位照射剂量60Gy/12次,等效生物剂量88-90Gy。结果:682例患者中,完全缓解(CR)87例(12.8%),部分缓解(PR)561例(82.2%),总有效率(CR+PR)为95%,其中III级以上放射性肺炎发生率5.2%(36/682),未出现明显的放射性食管炎。结论:非小细胞肺癌采用三维适形低分割高剂量放射治疗(5Gy/次,每周3-5次,中位照射剂量60Gy/12次),是相对安全的;而且局部控制率高,有较好的近期疗效,并发症低,值得推广使用。 相似文献
997.
Wang X Han L Zhang A Wang G Jia Z Yang Y Yue X Pu P Shen C Kang C 《Oncology reports》2011,25(1):97-105
Aberrantly expressed miRNAs are linked to the regulation of oncogenes and/or tumor suppression genes within the cell signal transduction pathway network, thereby contributing to carcinogenesis. miRNA function can be antagonized, thus representing a novel anti-tumor approach for integrated cancer therapy. In this study, we designed adenovirally-expressed shRNAs that functionally co-repressed the expression of miR-221 and miR-222, which are related to glioblastoma, to overcome the low efficiency of gene therapy. In addition, we generated novel shRNAs whose 3' ends were mutated in the region complementary to the target miRNA's 5' seed region to reduce the stability of binding with the miRNA. Various inhibition levels of miRNA were achieved: classic shRNAs yielded the greatest reduction in miRNA levels, followed by mutated shRNAs and the blank control, as determined by qRT-PCR. These results were confirmed by the protein expression of p27kip1, the validated target of miR-221/222, the effect on cell cycle arrest in G1 phase, and the impact on cell apoptosis. These results suggested that we could produce shRNAs encoded by adenovirus that co-repressed multiple tumor-related miRNAs simultaneously, and that the level of repression and the effect on the function of a specific miRNA could be achieved in a semi-quantitative manner. 相似文献
998.
The mixed-lineage leukemia 3 (MLL3) gene, which encodes an important component of a histone H3 lysine 4 methyltransferase complex named the ASC-2- and Mll3-containing complex (ASCOM), has been implicated as a tumor suppressor gene due to its frequent mutations in multiple types of human tumors as well as tumor induction upon targeted inactivation of the gene in mice. The role of MLL3 in breast cancer, however, remains unknown. In this study, we sequenced all 59 exons of MLL3 (14.7 Kb coding sequence) in 38 breast cancers from Chinese women, and found three somatic mutations in two of the cases, including one frameshift mutation (c.2687 ins A) that truncates the majority of the MLL3 protein, and two synonymous mutations. In addition to 24 known single nucleotide polymorphisms (SNPs), 5 novel SNPs were also detected in the 38 women; and interestingly, all the 5 novel SNPs alter amino acid sequences of MLL3 thus could have functional consequences. We also examined the expression of MLL3 mRNA in 30 breast tumors and their matched normal breast tissues. While no associations were found between expression change and clinicopathologic parameters, 40% of the samples showed reduced expression in cancer tissues. These results suggest that mutation of MLL3 plays a role in the development of breast cancer. 相似文献
999.
目的:探讨核因子кB受体激动子配体(receptor activator of nuclear factor κB ligand,RANKL)和骨保护因子(osteoprotegerin,OPG)在慢性根尖周炎发病中的作用。方法:采用RT-PCR法,从mRNA水平检测RANKL、OPG在10例慢性根尖周肉芽肿和3例根尖周囊肿中的表达。结果:RANKL mRNA在根尖周肉芽肿病损组和根尖周囊肿组明显增高,与正常对照组相比差异均有统计学意义(P<0.05),但根尖周肉芽肿和根尖囊肿组之间差异无显著性(P>0.05)。OPG mRNA仅在两个病损组织中检测到有低水平的表达,其余各病损组织和正常的牙周膜组织中均未检测到OPG mRNA的表达。结论:RANKL和OPG在慢性根尖周炎的发病中具有重要的作用,但也提示存在其他细胞因子的协同作用。 相似文献
1000.
目的 了解深圳地区13~18岁无明显下颌偏斜青少年的颌面部软组织对称性情况,探讨形成颌面部不对称的相关因素.方法 选取100名符合纳入标准的13~18岁青少年,通过肉眼观察以及软件测量对其正面照进行评估,分析影响颌面部软组织对称性的相关因素.结果 对称组及不对称组在性别构成比上无统计学差异(P>0.05).下颌角点Go'与口角点Ch到中线距离的比值在对称组(1.036±0.015和1.049±0.075)及非对称组(1.067±0.037和1.137±0.122)之间的差异具有统计学差异(P<0.05).下颌角点Go'与口角点Ch的非对称率在对称组与非对称组之间的差异具有统计学的差异(P<0.05).结论 深圳市青少年的颌面部软组织的不对称发生率未见性别差异.Go'、Ch非对称率均值分别达到了6.1%和11.1%之后,面部的不对称能为肉眼所识别.软组织下颌角点Go'为面部不对称的主要影响因素,正畸临床医师应谨慎评价生长发育期青少年正畸患者的颜面部对称性情况. 相似文献