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131.
Six selected plants, belonging to 3 families from Nanjing of China, were extracted with the solvent 95% (v/v) ethanol to yield 11 extracts. The extracts were evaluated for their effects on the growth of eight clinical bacteria, two fungi and one yeast using a modified agar diffusion method. The results showed that the majority of the extracts investigated showed greater activities against the Gram-positive bacteria than against the Gram-negative bacteria, the fungi and the yeast. The strongest antimicrobial activity was exhibited by the stem extracts of Mahonia fortunei against multiresistant Staphylococcus aureus strains, followed by the stem extracts of Mahonia bealei, while Bacillus thuringiensis was the most sensitive to all extracts.  相似文献   
132.
何浩  胡亮  何彩霞  崔嵘  夏凤强  李成 《生物磁学》2011,(17):3334-3338
目的:研究连续性血液净化联合乌司他丁对重症脓毒症患者炎症反应的影响及其临床疗效。方法:70例重症脓毒症患者随机分为对照组(n=22例)、CBP组(n=23例)和CBP+乌司他丁组(n=25例),其中对照组采用经典治疗方案,CBP组在此基础上加用连续性血液净化,CBP+乌司他丁组在CBP组基础上加用乌司他丁治疗。观察比较患者病情发展,分别于治疗前后进行血液生化指标、凝血功能检测和动脉血气分析,ELISA法检测血清CRP水平。结果:①与对照组和CBP组相比,CBP+鸟司他丁纽患者病死率、ICU住院时间、MODS发生率均明显下降(P〈0.05)。②经过治疗,CBP+乌司他丁组患者APACHEⅡ评分降至15.46±3.96,与对照组(18.06±4.25)和CBP组(17.14±5.55)比较差异有统计学意义(P〈0.05)。③治疗后,患者BUN、HR降低程度依次为CBP+乌司他丁组〉CBP组〉对照组,组问比较差异有显著性(P〈0.05),而治疗前后PH值、HCO3-、MAP比较差并不明显(P〉0.05)。④CBP+乌司他丁纽血清CRP含量下降,WBC数量减少,其变化程度明显大于CBP组和对照组(P〈0.05)。⑤对照组、CBP组和CBP+乌司他丁组患者PT、TT和APTT时间延长,血小板数量下降,其中CBP+鸟司他丁组PT、APTT时间短于CBP组和对照组(P〈0.05)。结论:连续性血液净化联合乌司他丁可有效抑制脓毒症患者炎症反应,缓解病情,改善患者预后。  相似文献   
133.
Wong KY  So CC  Loong F  Chung LP  Lam WW  Liang R  Li GK  Jin DY  Chim CS 《PloS one》2011,6(4):e19027
miR-124-1 is a tumour suppressor microRNA (miR). Epigenetic deregulation of miRs is implicated in carcinogenesis. Promoter DNA methylation and histone modification of miR-124-1 was studied in 5 normal marrow controls, 4 lymphoma, 8 multiple myeloma (MM) cell lines, 230 diagnostic primary samples of acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL), chronic myeloid leukaemia (CML), chronic lymphocytic leukaemia (CLL), MM, and non-Hodgkin's lymphoma (NHL), and 53 MM samples at stable disease or relapse. Promoter of miR-124-1 was unmethylated in normal controls but homozygously methylated in 4 of 4 lymphoma and 4 of 8 myeloma cell lines. Treatment of 5-Aza-2'-deoxycytidine led to miR-124-1 demethylation and re-expression of mature miR-124, which also associated with emergence of euchromatic trimethyl H3K4 and consequent downregulation of CDK6 in myeloma cells harboring homozygous miR-124-1 methylation. In primary samples at diagnosis, miR-124-1 methylation was absent in CML but detected in 2% each of MM at diagnosis and relapse/progression, 5% ALL, 15% AML, 14% CLL and 58.1% of NHL (p<0.001). Amongst lymphoid malignancies, miR-124-1 was preferentially methylated in NHL than MM, CLL or ALL. In primary lymphoma samples, miR-124-1 was preferentially hypermethylated in B- or NK/T-cell lymphomas and associated with reduced miR-124 expression. In conclusion, miR-124-1 was hypermethylated in a tumour-specific manner, with a heterochromatic histone configuration. Hypomethylation led to partial restoration of euchromatic histone code and miR re-expression. Infrequent miR-124-1 methylation detected in diagnostic and relapse MM samples showed an unimportant role in MM pathogenesis, despite frequent methylation found in cell lines. Amongst haematological cancers, miR-124-1 was more frequently hypermethylated in NHL, and hence warrants further study.  相似文献   
134.
Huo X  Qi X  Tang F  Zu R  Li L  Wu B  Qin Y  Ji H  Fu J  Wang S  Tian H  Hu Z  Yang H  Zhou M  Wang H  Zhu F 《PloS one》2011,6(3):e17995

Background

We investigated the seropositive rates and persistence of antibody against pandemic (H1N1) 2009 virus (pH1N1) in pregnant women and voluntary blood donors after the second wave of the pandemic in Nanjing, China.

Methodology/Principal Findings

Serum samples of unvaccinated pregnant women (n = 720) and voluntary blood donors (n = 320) were collected after the second wave of 2009 pandemic in Nanjing. All samples were tested against pH1N1 strain (A/California/7/2009) with hemagglutination inhibition assay. A significant decline in seropositive rates, from above 50% to about 20%, was observed in pregnant women and voluntary blood donors fifteen weeks after the second wave of the pandemic. A quarter of the samples were tested against a seasonal H1N1 strain (A/Brisbane/59/2007). The antibody titers against pH1N1 strain were found to correlate positively with those against seasonal H1N1 strain. The correlation was modest but statistically significant.

Conclusions and Significance

The high seropositive rates in both pregnant women and voluntary blood donors suggested that the pH1N1 virus had widely spread in these two populations. Immunity derived from natural infection seemed not to be persistent well.  相似文献   
135.
We have determined the type of stop codon specificity of Blepharisma japonicum translation termination factor eRF1 in an in vitro reconstituted eukaryotic translation system and in in vivo assay (the dual reporter system). We have shown that B. japonicum eRF1 retained specificity towards all three stop codons although efficiency of peptydyl-tRNA hydrolysis in the presence of UGA is reduced in an in vitro assay. We suggest that since the heterotrich B. japonicum represents the earliest diverged lineage on phylogenetic tree of ciliates, B. japonicum has the universal genetic code as ancestor group for all ciliates.  相似文献   
136.
137.
EB病毒潜伏膜蛋白1在鼻咽癌细胞中通过ERK介导Ets-1表达   总被引:2,自引:0,他引:2  
为了探讨EB病毒编码的潜伏膜蛋白1(LMP1)对核转录因子Ets-1表达和活化的影响,并证实细胞外信号调节激酶1/2(ERK1/2)参与了该过程,选用可调控表达LMP1的鼻咽癌细胞系L7,应用蛋白质印迹法检测Ets-1、p-ERK蛋白质表达,免疫共沉淀-蛋白质印迹法检测Ets-1磷酸化状态,使用ERK1/2特异性小分子阻断物PD98059作用后,蛋白质印迹法检测p-ERK、Ets-1表达及磷酸化变化.结果显示:在L7细胞中诱导性LMP1可促进p-ERK、Ets-1蛋白质表达及其苏氨酸残基磷酸化,在一定范围呈时间和剂量效应;通过PD98059对诱导性LMP1作用的干预发现,p-ERK大部分表达被阻断,而Ets-1表达及其苏氨酸磷酸化也被部分阻断,以上结果提示ERK部分介导了LMP1诱导Ets-1表达和活化.  相似文献   
138.
Tissue microarray study for classification of breast tumors   总被引:7,自引:0,他引:7  
Clinical and pathological heterogeneity of breast cancer hinders selection of appropriate treatment for individual cases. Molecular profiling at gene or protein levels may elucidate the biological variance of tumors and provide a new classification system that correlates better with biological, clinical and prognostic parameters. We studied the immunohistochemical profile of a panel of seven important biomarkers using tumor tissue arrays. The tumor samples were then classified with a monothetic (binary variables) clustering algorithm. Two distinct groups of tumors are characterized by the estrogen receptor (ER) status and tumor grade (p = 0.0026). Four biomarkers, c-erbB2, Cox-2, p53 and VEGF, were significantly overexpressed in tumors with the ER-negative (ER-) phenotype. Eight subsets of tumors were further identified according to the expression status of VEGF, c-erbB2 and p53. The malignant potential of the ER-/VEGF+ subgroup was associated with the strong correlations of Cox-2 and c-erbB2 with VEGF. Our results indicate that this molecular classification system, based on the statistical analysis of immunohistochemical profiling, is a useful approach for tumor grouping. Some of these subgroups have a relative genetic homogeneity that may allow further study of specific genetically-controlled metabolic pathways. This approach may hold great promise in rationalizing the application of different therapeutic strategies for different subgroups of breast tumors.  相似文献   
139.
凝血酶和ADP刺激血小板肌动蛋白的聚合,腺苷、5′-氯-5′-脱氧腺苷及2′-脱氧腺苷抑制凝血酶和(或)ADP诱导的肌动蛋白聚合;腺苷和5′-氯-5′-脱氧腺苷对磷脂酰肌醇的磷酸化有抑制作用,且呈剂量效应关系;腺苷对凝血酶刺激的血小板中肌醇二磷酸的生成有抑制作用。本实验提示腺苷及其类似物对肌动蛋白聚合的抑制作用可能与它们对肌醇磷脂转换的抑制有关。  相似文献   
140.
Fusaric acid (FA) is a nonhost-selective toxin mainly produced by Fusarium oxysporum, the causal agent of plant wilt diseases. We demonstrate that FA can induce programmed cell death (PCD) in tobacco suspension cells and the FA-induced PCD is modulated by nitric oxide (NO) signalling. Cells undergoing cell death induced by FA treatment exhibited typical characteristics of PCD including cytoplasmic shrinkage, chromatin condensation, DNA fragmentation, membrane plasmolysis, and formation of small cytoplasmic vacuoles. In addition, caspase-3-like activity was activated upon the FA treatment. The process of FA-induced PCD was accompanied by a rapid accumulation of NO in a FA dose-dependent manner. Pre-treatment of cells with NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) or NO synthase inhibitor N G-monomethyl-arginine monoacetate (L-NMMA) significantly reduced the rate of FA-induced cell death. Furthermore, the caspase-3-like activity and the expression of PAL and Hsr203J genes were alleviated by application of cPTIO or L-NMMA to FA-treated tobacco cells. This indicates that NO is an important factor involved in the FA-induced PCD. Our results also show that pre-treatment of tobacco cells with a caspase-3-specific inhibitor, Ac-DEVD-CHO, can reduce the rate of FA-induced cell death. These results demonstrate that the FA-induced cell death is a PCD and is modulated by NO signalling through caspase-3-like activation.  相似文献   
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