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991.
An Affymetrix mouse genome array and differential in-gel electrophoresis (DIGE) techniques were used to investigate the pharmacological mechanisms of a mixture of herbs, designated CTCM, a compound of traditional Chinese medicine, for the treatment of increased permeability in mouse intestinal microvascular endothelial cells (MIMECs) induced by the Shiga-like toxin type II variant (SLT-IIv). MIMECs were challenged with 10 μg/ml SLT-IIv for 12 h and then treated with CTCM at a concentration of 200 μg/ml for 12 h. Total RNA and proteins from each treatment group were extracted from cultured MIMECs for analysis by the Affymetrix GeneChip® Mouse Genome 430 2.0 microarray and DIGE. The results obtained demonstrated that there were one genes downregulated and one genes upregulated, one protein downregulated and four proteins upregulated in the SLT-IIv group compared to the control group. In the CTCM group, four genes were upregulated, three genes were downregulated, a single protein was downregulated and a single protein was upregulated when compared to the control group. When the CTCM-treated group was compared to the SLT-IIv group, expression of one gene was found to be increased, and all other genes were decreased, with five proteins downregulated. Analysis of the data suggested that CTCM specifically and effectively reduced microvascular endothelial cell permeability to SLT-IIv in the treatment of pig edema disease. In the CTCM-treated group, hspa9 expression was increased in both gene chip and DIGE analysis, so it may be a key protein in reducing cell permeability and utilized in medical treatments.  相似文献   
992.
Surrobodies2 are a unique type of binding protein based on the pre-B-cell receptor (pre-BCR). The pre-BCR is transiently expressed during development of the antibody repertoire. Unlike heterotetrameric canonical antibodies that are composed of identical pairs of heavy and light chains, the pre-BCR is a heterohexameric complex composed of identical pairs of heavy chains that are each paired with a two-subunit surrogate light chain (SLC). The SLC contains nonimmunoglobulin-like peptide extensions on each of the two SLC components. This arrangement provides unique opportunities for protein engineering by functional derivatization of these nonimmunoglobulin-like tails. Here we report recombinant fusions to these tails with either a fully active cytokine or with single-chain variable fragment (scFv) domains to generate Surrobodies with unique functions or Surrobodies that are bispecific with respect to targeted binding.  相似文献   
993.
To study the impact of nitrogen deposition on 1-year-old Chinese fir (Cunninghamia lanceolata) seedlings in pots, the dissolved NH4NO3 was sprayed on the seedlings every 3 days for 1 year. The simulated elevated N depositions were equivalent to N0(0), N1(6 gN/(m2 a)), N2(12 gN/(m2 a)), N3(24 gN/(m2 a)) and N4(48 gN/(m2 a)). The results indicated that medium N treatments (N2, N3) enhanced growth significantly. The height, stem base diameter and per-seedling biomass of Chinese fir seedlings increased with N loads and decreased in the high N treatments. Compared to N0, the height and per-seedling biomass were highest in N2 treatment and increased by 10.77% and 12.35%, respectively. The stem base diameter was highest in N3 treatment and increased by 8.81% compared to N0. The net photosynthetic rate (Pn) in treatments N1, N2, N3, N4 increased by 1.20%, 9.28%, 24.23% and 4.30%, and the highest photosynthetic rate by 67.09%, 125.32%, 148.10% and 51.90%, respectively. The N1–N3 treatments, especially N2, stimulated light compensation point (LCP) of the seedlings significantly, but N4 exhibited inhibitive effect. Compared with LCP, light saturation point (LSP) showed weaker response to N loads, positive to N2, but negative to all other N treatments. Low-to-medium N treatments (N1, N2) enhanced Chl (a + b) by 2.19% and 37.15%, while medium-to-high N treatments (N3, N4) reduced Chl (a + b) by 7.95% and 15.56%, respectively. Water use efficiency (WUE) and stomatal conductance (C) decreased slightly with N loads.  相似文献   
994.
通过建立的选择性膜型前列腺素E2合酶-1(mPGES-1)表达抑制剂的体外细胞筛选模型,对50味中药共236个样品进行筛选。初筛中,筛选中药不同极性提取物对mPGES-1表达的抑制作用,抑制率50%的样品进入复筛;复筛中,检测初筛活性样品对环氧化酶(COX)-1和COX-2表达的抑制作用,抑制率均20%的样品认为是阳性物。结果表明,吲哚美辛对3种酶的抑制活性与文献报道相近;筛选发现泽泻组分1、蒲黄组分2对mPGES-1的表达有可重复的选择性抑制作用,对泽泻组分1、蒲黄组分2进行进一步研究,有望确定其抗炎的有效部位或化合物。  相似文献   
995.
中国第四纪晚期孢粉记录整理   总被引:2,自引:0,他引:2       下载免费PDF全文
倪健  陈瑜  董丹 《植物生态学报》2010,34(8):1000-1005
孢粉数据库是重建过去植被格局以及研究古气候变化和大气圈-生物圈-人类活动相互关系的基础,而孢粉取样信息的记录和整理是建立孢粉数据库的重要前提。该文在收集我国1960–2008年发表的孢粉研究文献的基础上,整理分析了第四纪晚期,尤其是2万年以来(全新世为主)全国孢粉采样点的信息,包括采样地点名称、详细采样位置、省份、采样点经纬度和海拔高度、样品类型、取样深度、孢粉样品数量、14C测年数量及年代记录、覆盖的时间段和参考文献。总结发现,我国目前共有2324个表土/湖泊表层花粉采样点和987个第四纪晚期的地层沉积剖面和钻孔,其中高质量的地层孢粉采样点714个。虽然我国以及部分国际上从事第四纪研究的科学家尽了最大努力开展中国疆域的孢粉学研究,但由于人力、物力以及地形条件的限制,在我国仍然存在部分孢粉采样的"地理空隙",比如北方和西北荒漠地区、青藏高原无人区、中南部山区和东部人类活动频繁区域。然而,该数据信息库的不断完善,将为中国第四纪孢粉数据库的建立奠定良好基础。  相似文献   
996.
Recent evidence suggests that scavenger receptor, class B, type I (SR-BI) plays a physiological role in VLDL metabolism. SR-BI was reported to mediate β-VLDL uptake; however, cellular details of this process are not well characterized. In the present study we show that SR-BI delivers cholesterol derived from β-VLDL to LDL receptor negative SR-BI over-expressing Chinese Hamster Ovarian cells (ldlA7-SRBI). Cell association of β-VLDL was ∼ 3 times higher after SR-BI over-expression, which was competed by β-VLDL, but only to a lesser extent by HDL and LDL. Almost all of the associated β-VLDL was located intracellularly, and therefore could not be released by a 50-fold excess of unlabeled β-VLDL. β-VLDL was degraded at a rate of 6 ng β-VLDL/mg cell protein and hour. In contrast to ldlA7 cells, β-VLDL association was competed by LDL in cells with a functional LDL receptor like CHO and HepG2 cells, indicating a strong impact of the LDL receptor in β-VLDL uptake. β-VLDL degradation was similar to ldlA7-SRBI cells. When β-VLDL uptake was followed using fluorescence microscopy, β-VLDL showed a different uptake pattern in SR-BI over-expressing cells, ldlA7-SRBI, compared to LDL receptor containing cells, CHO and HepG2.  相似文献   
997.
Syndrome of Chinese medicine is an understanding of the regularity of disease occurrence and development and its performance of symptoms. Syndrome is the key to recognize diseases and the foundation to treat them. However, because of the complexity of the concept and the limitation of present investigations, the research of syndrome is hard to go further. Proteomics has been received extensive attention in the area of medical diagnosis and drug development. In the holistic and systemic context, proteomics have a convergence with traditional Chinese medicine (TCM) syndrome, which could overcome the one-sidedness and singleness of TCM and avoid the complication and tedious processes. Chinese medicine has a wealth of experience and proteomics has a substantial research potential, the integration of the two aspects will bring a great enhancement of our knowledge of disease.  相似文献   
998.
A rapid, sensitive, and specific method by high‐performance liquid chromatography (HPLC) coupled to diode‐array detection (DAD) and tandem mass spectrometry (MS) techniques was developed for the identification of absorbed constituents and their metabolites in rats after the oral administration of a Chai‐Huang decoction (CHD), which consists of Bupleurum chinense and Scutellaria baicalensis in the proportion 1 : 1 (w/w). By comparing their retention times and MS data with those of authentic compounds and published data, a total of 14 compounds were identified in the CHD samples. In addition, eleven and seven compounds were characterized in the urine and serum samples of the rats, respectively. The results indicated that the main absorbed constituents were chrysin‐6‐C‐arabinosyl‐8‐C‐glucoside, chrysin‐6‐C‐glucosyl‐8‐C‐arabinoside, baicalin, wogonin‐5‐O‐glucoside, oroxylin A‐7‐O‐glucuronide, wogonoside, saikosaponin A, saikosaponin C, saikosaponin D, baicalein, and wogonin. These compounds might be responsible for the curative effects of the CHD. The findings demonstrated that the proposed method could be used to rapidly and simultaneously analyze and screen the multiple absorbed bioactive constituents in a formula of traditional Chinese medicines (TCM). This is very important not only for the pharmaceutical discovery process and the quality control of crude drugs but also to explain the mechanisms of action of TCM.  相似文献   
999.
双向发酵——毒性中药炮制减毒的新途径   总被引:4,自引:0,他引:4  
涂霞  潘扬 《菌物研究》2010,8(1):52-56
就现代双向发酵工艺替代传统杂菌发酵工艺,运用于毒性成分分别为生物碱、内酯物质、苷类化合物、毒蛋白、马兜铃酸、蒽醌、鞣质和重金属8类毒性中药炮制减毒的可行性、可靠性进行综合论述。  相似文献   
1000.
不同含水量大葱种子贮藏过程中的糖代谢研究   总被引:3,自引:1,他引:2  
将大葱种子干燥到1.8%~10.5%的不同含水量后,在50℃、35℃、20℃和-18℃条件下密闭贮存16个月。通过对半乳糖、葡萄糖、果糖、蔗糖和密三糖含量研究的结果表明,随着贮存温度的升高,种子中半乳糖的含量不断升高,随着含水量的降低,种子中半乳糖的含量逐渐降低,且随着贮存温度的下降,种子中半乳糖含量随种子含水量下降而降低的趋势减缓。然而葡萄糖、果糖、蔗糖和密三糖的结果与半乳糖的变化趋势相反,随着贮存温度的升高,4种糖的含量逐渐下降,在同一贮藏温度条件下,随含水量的降低这4种糖的含量却逐渐升高,但在贮存温度较低时(20℃和~18℃),这种变化趋势不明显。  相似文献   
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