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251.
本文对中国首例输入性D8基因型麻疹病毒基因特征进行分析。用ELISA法检测血清麻疹病毒IgM抗体;用Vero/Slam细胞对采集的咽拭子标本进行病毒分离,分离到的麻疹毒株用RT-PCR方法扩增其核蛋白基因3′端的部分序列,并对扩增产物进行核苷酸序列测定和分析,以3′端456个核苷酸为目的片段进行基因亲缘性关系分析。结果表明,上海市2012年共报告1 105疑似麻疹病例,其中实验室确诊590例,临床符合病例2例,排除513例,报告发病率为2.52/10万;共采集到984份疑似麻疹病例咽拭子标本,分离到247株麻疹病毒,病毒分离阳性率为25.3%;除Shanghai12-239为D8基因型外,其他均为H1a基因亚型。Shanghai12-239与世界卫生组织(World Health Organization,WHO)参考株(Manchester.UNK30.94(D8)AF280803)核苷酸序列同源性为97.8%,氨基酸序列同源性为98.6%。与WHO其他基因型参考株核苷酸序列同源性为89.6%~94.5%,氨基酸序列同源性为88.7%~95.3%。 相似文献
252.
目的探讨内质网应激在高脂饮食引起的ApoE基因敲除小鼠附睾损伤中的作用及褪黑素(MT)的干预机制。方法将12只ApoE基因敲除的C57BL/6J雄性小鼠随机分为高脂饮食组及MT处理组。高脂饮食组为ApoE基因敲除小鼠,给予高脂饮食;MT处理组给予高脂饲养外,并MT灌胃。以6只野生型C57BL/6J雄性小鼠作为对照组,给予普通饮食。饲养12w后,取附睾组织制片,HE染色观察附睾的病理学形态,免疫组化检测GRP78和CHOP的表达。结果HE染色显示,高脂饮食组小鼠,附睾上皮细胞形态结构不清,细胞萎缩。对照组和褪黑素处理组小鼠附睾上皮细胞形态结构完整,细胞排列整齐。免疫组化显示高脂饮食组小鼠附睾中GRP78、CHOP表达增强(P〈0.01)。MT处理组和高脂饮食组相比,附睾中GRP78、CHOP表达下调(P〈0.01)。结论内质网应激参与高脂饮食导致的附睾损伤;MT可能通过抑制附睾内质网应激,减轻高脂饮食对小鼠附睾的损伤。 相似文献
253.
Kazunori Sasaki Tomoyuki Oki Yumi Kai Yoichi Nishiba 《Bioscience, biotechnology, and biochemistry》2013,77(8):1308-1314
The purpose of this study was to investigate the effect of repeated harvesting on the content of caffeic acid (CA) and seven species of caffeoylquinic acids (CQAs) in sweet potato leaves using a newly developed high-performance liquid chromatography method. Six cultivars and two breeding lines were used in this study. Leaves were collected at monthly intervals from 1st harvest (May) to 4th harvest (August) in 2011 and 2012. ANOVA analysis revealed that the contents of CQAs were significantly different among all cultivars and breeding lines, but no significant differences were found for CA. No annual variation was confirmed in CA and CQAs. Repeated harvest of sweet potato leaves affected the content of only 4-CQA and 5-CQA. Post-hoc comparisons using Tukey’s method indicated that the contents of 4-CQA and 5-CQA in sweet potato leaves harvested at first time were significantly higher compared to those at the other harvest times. 相似文献
254.
通过比较4种小鼠粪便细菌总DNA提取方法对基于PCR-DGGE检测的肠道菌群多样性分析的影响,旨在建立适于PCR—DGGE的小鼠肠道微生物宏基因组提取的稳定、经济、快捷的方法。采用SDS裂解法、某国产市售粪便DNA提取试剂盒、改进的化学裂解法、改进的溶菌酶法4种方法提取小鼠粪便细菌总DNA,通过琼脂糖凝胶电泳、紫外分光光度法、细菌16S rRNAV3区PCR扩增结合DGGE对提取结果进行比较分析。SDS裂解法和国产市售试剂盒2种方法提取粪便细菌总DNA均未得到理想结果,另2种方法均能够检测到粪便中20种左右的细菌。改进的化学裂解法和改进的溶菌酶提取法的建立为基于PCR—DGGE进行肠道菌群结构的定量及定性分析提供了可靠的前提基础和实验保障。 相似文献
255.
Ling Xie Cui Liu Li Wang Harsha P. Gunawardena Yanbao Yu Ruyun Du Debra J. Taxman Penggao Dai Zhen Yan Jing Yu Stephen P. Holly Leslie V. Parise Yisong Y. Wan Jenny P. Ting Xian Chen 《Cell reports》2013,3(3):678-688
Highlights? PP2Ac is constitutively activated and targets MyD88 in LPS-tolerized macrophages ? Constitutively active PP2Ac shifts a proinflammatory MyD88 to its prosurvival mode ? Constitutively active PP2Ac reprograms gene-specific chromatin modification landscape ? Constitutively active PP2Ac broadly defines ET at both signaling and epigenetic levels 相似文献
256.
257.
Hujun PAN Basundhara CHETTRI Daode YANG Ke JIANG Kai WANG Liang ZHANG Gernot VOGEL 《亚洲两栖爬行动物研究(英文版)》2013,(2)
A new species of the genus Protobothrops Hoge Romano-Hoge, 1983, was described from Jilong County, southern Tibet, China, and Chungthang, northern Sikkim, India. It differs from congeners by the following characters: 1) relatively large body size(total length up to 1510 mm); 2) dorsal scale rows 25–25–19; 3) except for the smooth outermost row, dorsal scales are weakly keeled; 4) relatively high number of ventral(198–216) and subcaudal(65–76 pairs) scales; 5) 7–8 supralabials; 6) 11 to 13 infralabials; 7) dorsal head uniform dark brown, laterally a reddish-brown obscure postocular streak; 8) dorsum of trunk and tail olive, with distinct black edged red brown transverse bands across the body and tail; and 9) eye from bright brown and reddish brown to mildly brown. The new species was also observed from the Haa Valley in western Bhutan. 相似文献
258.
Background
Infantile hemangioma (IH) is a benign vascular neoplasm that arises from the abnormal proliferation of endothelial cells and enhanced angiogenesis. Recently, propranolol has been found to be effective in the management of IH, suggesting that β-adrenergic receptors (β-ARs) may play an important role in the pathogenesis of IH.Results
In the present study, we investigated the β-adrenergic signaling that is associated with hemangioma-derived endothelial cell (HemEC) proliferation. The results showed that both β1- and β2-ARs were expressed in HemECs. Stimulation of the β-ARs by isoprenaline induced cell proliferation and elevation of second messenger cAMP levels. The proliferation-promoting action of isoprenaline was abolished by a β1-selective antagonist and was more effectively abolished by a β2-selective antagonist; the mechanism for the action of the antagonists was a G0/G1 phase cell cycle arrest which was associated with decreased cyclin D1, CDK-4, CDK-6 and phospho-Rb expression. Pre-treatment of the cells with VEGFR-2 or ERK inhibitors also prevented the isoprenaline-mediated proliferation of cells. In agreement with the involvement of β-ARs and VEGFR-2 in the HemEC response, β-AR antagonists and the VEGFR-2 inhibitor significantly attenuated isoprenaline-induced ERK phosphorylation. Moreover, treating the cells with isoprenaline markedly increased VEGF-A expression and VEGFR-2 activity in a β2-AR-dependent manner.Conclusions
We have demonstrated that the activation of the β-ARs in the ERK pathway may be important mechanisms in promoting HemEC growth. Furthermore, stimulation of the β-AR may transactivate VEGFR-2 signaling and further increase HemEC proliferation. 相似文献259.
Shu Zhang Kai Jiang Chun Sun Haojie Lu Yinkun Liu 《Acta biochimica et biophysica Sinica》2013,(12):1021-1029
The site-specific characterization of N-glycans in glycopro- teins with the potential of clinical application is important. In our previous report, the overall N-glycans of sera haptoglobin (Hp) β chain were found to be different in liver diseases. Hp β chain contains four potential sites of N-glycosylation. In this study, we investigated the potential change of N-glycans on Hp β chain in a site-specific fashion. Sera Hp β chain in healthy individuals as well as patients with hepatitis B virus (HBV), liver cirrhosis (LC) and hepatocellular carcinoma (HCC) were purified, digested and subjected to liquid chromatography-electro- spray ionization-higher energy collision dissociation mass spectrometry, which allowed identification and structure determination of the glycopeptide, as well as the relative quantification of glycans present on each glycopeptide. The quantitative results revealed that the sialylation of NLFLN207HSEN211 ATAK and the fucosylated structure at all glycopeptides increased significantly in LC and HCC patients compared with those in HBV patients and healthy individuals. A set of different N-glycan patterns of Hp β chain in various liver diseases has been determined. Thus, the sialylated and fucosylated glycoforms of Hp β chain might be related to early hepatocarcinogenesis and also might be useful as novel differential markers for LC and HCC patients. 相似文献
260.
Lutz?HamannEmail author Alexander?Koch Saubashya?Sur Nadja?Hoefer Christiane?Glaeser Susanne?Schulz Michael?Gross Andre?Franke Ute?N?thlings Kai?Zacharowski Ralf?R?Schumann 《Immunity & ageing : I & A》2013,10(1):43