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191.
Proteome analysis of human lung squamous carcinoma   总被引:11,自引:0,他引:11  
Li C  Xiao Z  Chen Z  Zhang X  Li J  Wu X  Li X  Yi H  Li M  Zhu G  Liang S 《Proteomics》2006,6(2):547-558
Few lung cancer-specific molecular markers have been established in regard of "early-stage" diagnosis and prognosis. In this study the proteome analysis of human lung squamous carcinoma (hLSC) was carried out using two strategies to explore the carcinogenic mechanisms and identify its molecular markers more directly and comprehensively. Comparative proteome analysis on 20 hLSC tissues and paired normal bronchial epithelial tissues revealed 76 differential proteins, among which 68 proteins were identified by PMF. The identified proteins fell into three categories: oncoproteins, cell cycle regulators and signaling molecules. To validate the identified differential proteins, the expressions levels of three differential proteins mdm2, c-jun and EGFR were determined by immunohistochemical staining and immunoblots. The results verified proteome analysis results. Serological proteome analysis (SERPA) of ten hLSC tissues was performed to identify the tumor-associated antigens. The results revealed 36 +/- 8 differential proteins reactive with patients' autologous sera, of which 14 proteins were identified. Six of the 14 proteins, alpha enolase, pre-B cell-enhancing factor precursor, triosephosphate isomerase, phosphoglycerate mutase 1, fructose-bisphosphate aldolase A, and guanine nucleotide-binding protein beta subunit-like protein, were also up-regulated in hLSCs in the comparative proteomic study, which suggests potential application of these 6 hLSC-associated antigens in diagnosis and therapy of hLSC.  相似文献   
192.
Structural genomics efforts have produced structural information, either directly or by modeling, for thousands of proteins over the past few years. While many of these proteins have known functions, a large percentage of them have not been characterized at the functional level. The structural information has provided valuable functional insights on some of these proteins, through careful structural analyses, serendipity, and structure-guided functional screening. Some of the success stories based on structures solved at the Northeast Structural Genomics Consortium (NESG) are reported here. These include a novel methyl salicylate esterase with important role in plant innate immunity, a novel RNA methyltransferase (H. influenzae yggJ (HI0303)), a novel spermidine/spermine N-acetyltransferase (B. subtilis PaiA), a novel methyltransferase or AdoMet binding protein (A. fulgidus AF_0241), an ATP:cob(I)alamin adenosyltransferase (B. subtilis YvqK), a novel carboxysome pore (E. coli EutN), a proline racemase homolog with a disrupted active site (B. melitensis BME11586), an FMN-dependent enzyme (S. pneumoniae SP_1951), and a 12-stranded β-barrel with a novel fold (V. parahaemolyticus VPA1032).  相似文献   
193.
The relationship between human fluid intelligence and social-emotional abilities has been a topic of considerable interest. The current study investigated whether adolescents with different intellectual levels had different automatic neural processing of facial expressions. Two groups of adolescent males were enrolled: a high IQ group and an average IQ group. Age and parental socioeconomic status were matched between the two groups. Participants counted the numbers of the central cross changes while paired facial expressions were presented bilaterally in an oddball paradigm. There were two experimental conditions: a happy condition, in which neutral expressions were standard stimuli (p = 0.8) and happy expressions were deviant stimuli (p = 0.2), and a fearful condition, in which neutral expressions were standard stimuli (p = 0.8) and fearful expressions were deviant stimuli (p = 0.2). Participants were required to concentrate on the primary task of counting the central cross changes and to ignore the expressions to ensure that facial expression processing was automatic. Event-related potentials (ERPs) were obtained during the tasks. The visual mismatch negativity (vMMN) components were analyzed to index the automatic neural processing of facial expressions. For the early vMMN (50–130 ms), the high IQ group showed more negative vMMN amplitudes than the average IQ group in the happy condition. For the late vMMN (320–450 ms), the high IQ group had greater vMMN responses than the average IQ group over frontal and occipito-temporal areas in the fearful condition, and the average IQ group evoked larger vMMN amplitudes than the high IQ group over occipito-temporal areas in the happy condition. The present study elucidated the close relationships between fluid intelligence and pre-attentive change detection on social-emotional information.  相似文献   
194.
By using a new Fragment-Based Virtual Screen strategy, two series of novel FBA-II inhibitors (thiourea derivatives) were de novo discovered based on the active site of fructose-1, 6-bisphosphate aldolase from Cyanobacterial (CyFBA). In comparison, most of the N-(2-benzoylhydrazine-1-carbonothioyl) benzamide derivatives (L14~L22) exhibit higher CyFBA-II inhibitory activities compared to N-(phenylcarbamothioyl) benzamide derivatives (L1~L13). Especially, compound L14 not only shows higher CyFBA-II activity (Ki?=?0.65?μM), but also exhibits most potent in vivo activity against Synechocystis sp. PCC 6803 (EC50?=?0.09?ppm), higher (7-fold) than that of our previous inhibitor (EC50?=?0.6?ppm). The binding modes of compound L14 and CyFBA-II were further elucidated by jointly using DOX computational protocol, MM-PBSA and site-directed mutagenesis assays. The positive results suggest that strategy adopted in this study was promising to rapidly discovery the potent inhibitors with novel scaffolds. The satisfactory algicide activities suggest that the thiourea derivatives is very likely to be a promising lead for the development of novel specific algicides to solve Cyanobacterial harmful algal blooms (CHABs).  相似文献   
195.
以江苏省苏州吴中区山地种植的24个枇杷果园的‘白玉’枇杷为研究对象,采用典型相关分析法研究土壤、叶片和果实矿质元素间及其与果实品质指标的相关性,应用多元线性回归分析法筛选影响枇杷果实品质的土壤、叶片和果实的主要矿质元素和影响叶片矿质元素的主要土壤矿质养分因子,为改善枇杷果实品质的果园营养管理技术提供理论参考依据。结果表明:(1)枇杷果实品质指标在不同果园间存在较大差异。(2)枇杷果实品质主要受其叶片和果实矿质元素含量影响,其中:枇杷单果质量与叶片中N含量呈显著正相关,与果实中N含量呈显著负相关;可溶性固形物含量与叶片中N和Mg元素含量呈极显著正相关,与果实中P、Mn元素含量呈极显著正相关,与果实中Ca、Mg元素含量呈极显著负相关;可滴定酸含量与叶片中N和Zn元素含量呈显著负相关,与果实中N、Mn元素含量呈显著负相关,与果实中Ca元素含量呈显著正相关。(3)果实品质指标与土壤矿质养分含量的相关性较弱,土壤矿质养分主要通过影响叶片矿质元素含量,进而间接影响果实品质,其中土壤中P、K、Ca、Mn、Cu元素对叶片中矿质元素含量影响较大。研究认为,提高土壤中P、K、Zn含量并减少土壤Ca含量是东山山地枇杷果园土壤管理的关键技术途径;提高叶片中N含量以及果实中N、P、Mn含量和减少果实中Ca、Mg含量是改善东山山地枇杷果实品质的关键措施。  相似文献   
196.
We developed an inexpensive, fast and reliable PCR method for sex identification of giant panda (Ailuropoda melanoleuca) by using one pair of primers to co-amplify homologous fragments with size polymorphism that located at amelogenin (AMEL) exon 5. In giant panda, a 63 bp deletion in exon 5 of Y-linked allele provides a significant discrimination between AMELX and AMELY, thus the amplification products can be distinguished simply by agarose gel electrophoresis, exhibiting sex-specific banding patterns (male: 237 bp, 174 bp; female: 237 bp). Both blood and feces samples from known-sex giant pandas were successfully amplified. Cross species test also revealed that this method could be applied to other Ursidae species. These authors contributed equally to this work.  相似文献   
197.
以细胞质雄性不育花椰菜ogura-A和相应的保持系ogura-B为材料进行ISSR及DDRTPCR分析.选用30条ISSR引物,经扩增共产生306条清晰可辨的条带.每条引物可产生6-12条带,其中引物ISSR3在两系中呈现多态性扩增,在保持系中特异扩增出一条1100 bp的片段,序列分析表明该片段与油菜、拟南芥线粒体基因组的部分序列高度相似.推测其可能来源于花椰菜线粒体基因组.在DDRT-PCR分析中,选用3条锚定引物、15条随机引物进行组合,最终共获得1 122条大小在1 000-50 bp的带.经反向Northern杂交验证只有4条带特异的存在于两系中,分别命名为ogura-A205、ogura-A383、ogura-B307、ogura-B352.其中ogura-A205、ogura-A 383只在细胞质雄性不育系中表达,而ogura-B307、ogura-B352在保持系中呈现特异性表达,分析表明四个差异序列均为首次报道.其中ogura-A205、ogura-B307至今尚未发现与之相似的序列,有待于进一步研究;ogura-A383、ogura-352与报道的拟南芥、大白菜等的叶绿体基因的一些片段具较高相似性,推测ogura-A33、ogura-B352搅可能来源于花椰菜叶绿体基因组.以上结果为进一步阐明花椰菜细胞质雄性不育及育性保持的分子机制提供了新线索.  相似文献   
198.
199.
This pilot study evaluated the feasibility and effectiveness of conducting a double-blind clinical trial for the prevention of lung cancer with selenium (Se) in Yunnan Tin Corporation, the People's Republic of China, where the incidence rates of lung cancer are extraordinarily high among the miners. Forty healthy miners were randomized to either 300 μg of Se in high Se malt cakes or an identical placebo of malt cakes daily for one year. Subjects consumed their usual daily diet. The low Se concentrations in plasma (0.05±0.008 μg/mL) and hair (0.442±0.085 μg/g) reflected their low dietary Se intake in the control subjects. In Se-supplemented group, the Se status was increased by 178% for serum and 194.8% for hair. The serum GSHpx activity was increased by 155.7%, whereas the lipid peroxide level was reduced by 74.5% compared to the placebo. The results of UDS assay indicated that the lymphocyte DNA damage induced by ultraviolet irradiation and carcinogen 3,4-benzpyrene could be protected by Se supplementation. Se-supplementation did not affect the liver function test (SGPT), as well as the concentrations of hemoglobin, albumin, and cholesterol. Thus, daily intake of 300 μg Se in form of Se-malt as a chemopreventive measure is safe and effective to humans with low Se status.  相似文献   
200.
几种离子及有机物对蜡样芽胞杆菌蛋白酶活力的影响   总被引:4,自引:3,他引:4  
研究不同浓度的金属离子及有机物对蜡样芽胞杆菌蛋白酶活力的影响,结果表明①五种无机离子中Mg  相似文献   
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