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81.
82.
Antiviral flavonoids from the root bark of Morus alba L 总被引:7,自引:0,他引:7
A prenylated flavonoid, moralbanone, along with seven known compounds kuwanon S, mulberroside C, cyclomorusin, eudraflavone B hydroperoxide, oxydihydromorusin, leachianone G and alpha-acetyl-amyrin were isolated from the root bark of Morus alba L. Leachianone G showed potent antiviral activity (IC(50) = 1.6 microg/ml), whereas mulberroside C showed weak activity (IC(50) = 75.4 microg/ml) against herpes simplex type 1 virus (HSV-1). Their structures were elucidated by spectroscopic methods. 相似文献
83.
社会竞争失败病因学的抑郁症树鼩模型 总被引:2,自引:0,他引:2
抑郁症是一种常见精神疾病,主要表现为持续两周以上的情绪低落。世界卫生组织预测在2030年抑郁症的疾病负担将高居所有疾病、伤残总负担的榜首。抑郁症面临三大难题:1)发病机理不完全清楚,因而缺乏有效的预测预防途径和生物学诊断;2)现有单胺类抗抑郁症药物起效慢,也可能导致患者自杀风险增加;3)缺乏副作用小的非单胺类快速起效抗抑郁症药物。针对这三大难题,长期以来,应用抑郁症啮齿类模型的众多研究并未取得实质性进展,至少部分因素归咎于啮齿类与人类大脑功能的极大种属差异。树鼩是灵长类近亲,具有更接近于人类的大脑功能。本文针对抑郁症发病机理假说、临床表象和抗抑郁症药物疗效等内容,综述了社会竞争失败病因学的抑郁症树鼩模型可能会具有更好的疾病同源性、表象一致性和药物预见性。这一被长期忽视的抑郁症树鼩模型尽管还需要进一步完善,但对其进一步深入研究可能为解决抑郁症的三大难题提供了一条新途径。 相似文献
84.
85.
Santosuosso M Zhang X McCormick S Wang J Hitt M Xing Z 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(12):7986-7994
The mechanisms underlying better immune protection by mucosal vaccination have remained poorly understood. In our current study we have investigated the mechanisms by which respiratory virus-mediated mucosal vaccination provides remarkably better immune protection against pulmonary tuberculosis than parenteral vaccination. A recombinant adenovirus-based tuberculosis (TB) vaccine expressing Mycobacterium tuberculosis Ag85A (AdAg85A) was administered either intranasally (i.n.) or i.m. to mice, and Ag-specific CD4 and CD8 T cell responses, including frequency, IFN-gamma production, and CTL, were examined in the spleen, lung interstitium, and airway lumen. Although i.m. immunization with AdAg85A led to activation of T cells, particularly CD8 T cells, in the spleen and, to a lesser extent, in the lung interstitium, it failed to elicit any T cell response in the airway lumen. In contrast, although i.n. immunization failed to effectively activate T cells in the spleen, it uniquely elicited higher numbers of Ag-specific CD4 and CD8 T cells in the airway lumen that were capable of IFN-gamma production and cytolytic activities, as assessed by an intratracheal in vivo CTL assay. These airway luminal T cells of i.n. immunized mice or splenic T cells of i.m. immunized mice, upon transfer locally to the lungs of naive SCID mice, conferred immune protection against M. tuberculosis challenge. Our study has demonstrated that the airway luminal T cell population plays an important role in immune protection against pulmonary TB, thus providing mechanistic insights into the superior immune protection conferred by respiratory mucosal TB vaccination. 相似文献
86.
Lipidomic changes during different growth stages of Nitzschia closterium f. minutissima 总被引:3,自引:0,他引:3
Xiaoling Su Jilin Xu Xiaojun Yan Peng Zhao Juanjuan Chen Chengxu Zhou Fang Zhao Shuang Li 《Metabolomics : Official journal of the Metabolomic Society》2013,9(2):300-310
Ultra Performance Liquid Chromatography-Electrospray ionization-Quadrupole-Time of Flight Mass Spectrometry (UPLC-ESI-Q-TOF–MS) is a powerful lipidomic tool. In this study, we developed a UPLC/Q-TOF–MS based method to investigate the lipid metabolomic changes in different growth phases of Nitzschia closterium f. minutissima. The data classification and biomarker selection were carried out by using multivariate statistical analysis, including principal components analysis (PCA), projection to latent structures with discriminant analysis (PLS-DA), and orthogonal projection to latent structures with discriminant analysis (OPLS-DA). We discovered that the intercellular lipid metabolites were significantly different among exponential, early stationary and late stationary phases. Thirty-one lipid molecules were selected and identified as putative biomarkers, including free fatty acid, Harderoporphyrin, phosphatidylglycerol, 1,2-diacyglycerl-3-O-4′-(N,N-trimethy)-homoserine, triacylglycerol, cholesterol, sulfoquinovosyldiacylglycerol, lyso-sulfoquinovosyldiacylglycerol, monogalactosyldiacylglycerol, digalactosyldiacylglycerol and lyso-digalactosyldiacylglycerol. These lipids have been shown previously to function in energy storage, membrane stability and photosynthesis efficiency during the growth of diatoms. Further analysis on the putative biomarkers demonstrated that nitrate starvation played critical role in the transition from exponential phase to stationary phase in N. closterium. This study is the first one to explore the lipidomic changes of microalgae in different growth phases, which promotes better understanding of their physiology and ecology. 相似文献
87.
88.
为了降低bFGF(basic fibroblast growth factor)的生产成本,结合植物生物反应器的优点,就bFGF在转基因苜蓿中的表达进行了探索.将bFGF插入植物表达载体pBⅡ21中,获得了含有bFGF基因的植物表达pBIcbFGF,再将pBIcbFGF利用冻融法转到农杆菌中.利用农杆菌介导法将基因转化保定苜蓿,转基因苜蓿在TM-1培养基+20 mg/L卡那霉素(Kan)+200 mg/L特美汀(Tim)中诱导分化,在生根培养基中生根,获得再生植株.再生植株通过PCR检测、RT-PCR及Western blot证实外源基因已经在苜蓿中成功表达.获得含有目的蛋白的阳性植株.为苜蓿作为植物生物反应器生产bFGF奠定了理论及技术基础. 相似文献
89.
Isolation of a novel 38 residue-hypothalamic polypeptide which stimulates adenylate cyclase in pituitary cells 总被引:45,自引:0,他引:45
A Miyata A Arimura R R Dahl N Minamino A Uehara L Jiang M D Culler D H Coy 《Biochemical and biophysical research communications》1989,164(1):567-574
A novel neuropeptide which stimulates adenylate cyclase in rat anterior pituitary cell cultures was isolated from ovine hypothalamic tissues. Its amino acid sequence was revealed as: His-Ser-Asp-Gly-Ile-Phe-Thr-Asp-Ser-Tyr-Ser-Arg-Tyr-Arg-Lys-Gln- Met-Ala- Val-Lys-Lys-Tyr-Leu-Ala-Ala-Val-Leu-Gly-Lys-Arg-Tyr-Lys-Gln-Arg-Val-Lys-Asn-Lys - NH2. The N-terminal sequence shows 68% homology with vasoactive intestinal polypeptide (VIP) but its adenylate cyclase stimulating activity was at least 1000 times greater than that of VIP. It increased release of growth hormone (GH), prolactin (PRL), corticotropin (ACTH) and luteinizing hormone (LH) from superfused rat pituitary cells at as small a dose as 10(-10)M (GH, PRL, ACTH) or 10(-9)M (LH). Whether these hypophysiotropic effects are the primary actions of the peptide or what physiological action in the pituitary is linked with the stimulation of adenylate cyclase by this peptide remains to be determined. 相似文献
90.